61 results on '"Yue Zou"'
Search Results
2. Population pharmacokinetics of sirolimus in Chinese adult liver transplant recipients: a retrospective study
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Yang Zhang, Xuanling Zhang, Yue Zou, Yiqi Sun, and Xingang Li
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Pharmacology ,Adult ,Sirolimus ,China ,Health, Toxicology and Mutagenesis ,Humans ,General Medicine ,Toxicology ,Biochemistry ,Models, Biological ,Immunosuppressive Agents ,Liver Transplantation ,Retrospective Studies - Abstract
Considering the significant interindividual variability and a narrow therapeutic index, we aimed to determine the population pharmacokinetics (PPK) of sirolimus and identify the factors in Chinese adult liver transplant recipients.Data were retrospectively extracted from adult liver transplant recipients receiving sirolimus in our hospital. The trough blood concentration data, obtained from traditional therapeutic drug monitoring-based dose adjustments, were used to develop a population pharmacokinetic model by non-linear mixed-effects modelling (NONMEM). The effect of demographic features, biological characteristics and concomitant medications was measured. The final model was verified by visual prediction check (VPC), bootstrap, and simulation.One hundred and sixteen blood concentrations from 63 patients were analysed. The PPK of sirolimus could be described by a one-compartment model with first-order absorption. Covariate analysis indicated that voriconazole co-therapy significantly decreased the oral clearance (CL) of sirolimus. The results of VPC and Bootstrap demonstrated that the final pharmacokinetic model adequately predicted observed concentrations. The simulation results showed that the dosage regimen of sirolimus should be reduced to 0.25 ∼ 0.45 mg/day for adult liver transplant recipients co-administered with voriconazole. The present study developed and validated a sirolimus PPK model for Chinese adult liver transplant recipients, and voriconazole co-therapy was found to be a significant covariate in the model. These results provide important information for clinicians to optimise the treatment regimens of sirolimus in Chinese adult liver transplant recipients.
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- 2022
3. Changes in esophagus interstitial cells of Cajal in response to acute stress
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Zhen-peng Huang, Hu Qiu, Ke Wang, Jia-wei He, Hang Chen, Ling-wang Kong, and Yue Zou
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Proto-Oncogene Proteins c-kit ,Esophagus ,Epinephrine ,Hydrocortisone ,Dopamine ,Gastroenterology ,Interleukin-9 ,Animals ,Humans ,Rabbits ,Interstitial Cells of Cajal - Abstract
Thoracic trauma is common, and traffic accident-related traumatic injury can cause acute stress leading to esophageal motility disorders. Interstitial cells of Cajal (ICCs) are regarded as gastrointestinal pacemaker cells.This study explored the mechanism underlying changes in lower esophagus ICCs under acute stress conditions.Fifty adult rabbits, randomly divided into one healthy control and four study groups, were subjected to right chest puncture using a Hopkinson bar. Thereafter, one group was immediately subjected to lower esophagectomy, whereas the other three groups were maintained for 24, 48 and 72 h after puncture and subjected to lower esophagectomy. Immunohistochemistry was used to detect ICC distribution, morphology and density, and TUNEL assays were used to determine ICC apoptosis. Enzyme-linked immunosorbent assays (ELISAs) were used to measure cortisol, epinephrine, dopamine, IL-9, cholecystokinin (CCK) and vasoactive intestinal peptide (VIP). Western blotting and RT-PCR were performed to detect changes in SCF/c-kit and nNOS pathways.After puncture, lung tissue was hemorrhaged, alveoli in puncture areas were destroyed, esophageal pH was decreased, and serum cortisol, epinephrine and dopamine levels increased. ICC numbers increased and apoptotic ICCs decreased in all stress groups after puncture (allAcute stress promotes increases in lower esophageal ICCs that might affect esophagus ICC functions and esophageal motility.
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- 2022
4. Radiation-activated secretory proteins of
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Yi, Ban, Geoffrey J, Markowitz, Yue, Zou, Divya, Ramchandani, Jeffrey, Kraynak, Jianting, Sheng, Sharrell B, Lee, Stephen T C, Wong, Nasser K, Altorki, Dingcheng, Gao, and Vivek, Mittal
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Mice ,Lung Neoplasms ,Carcinoma, Non-Small-Cell Lung ,Animals ,Humans ,Uteroglobin ,Immune Checkpoint Inhibitors - Abstract
Radiation therapy (RT) in combination with immune checkpoint inhibitor (ICI) represents a promising regimen for non-small cell lung cancer (NSCLC), however, the underlying mechanisms are poorly characterized. We identified a specific dose of RT that conferred tumor regression and improved survival in NSCLC models when combined with ICI. The immune-modulating functions of RT was ascribed to activated lung-resident Scgb1a1+ club cells. Importantly, mice with club cell-specific knockout of synaptosome-associated protein 23 failed to benefit from the combination treatment, indicating a pivotal role of club cell secretome. We identified 8 club cells secretory proteins, which inhibited immunosuppressive myeloid cells, reduced pro-tumor inflammation, and enhanced anti-tumor immunity. Notably, CC10, a member of club cell secretome was increased in plasma of NSCLC patients responding to the combination therapy. By revealing an immune-regulatory role of club cells, our studies have the potential to guide future clinical trials of ICI in NSCLC.
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- 2021
5. IFNγ-induced PD-L1 expression in ovarian cancer cells is regulated by JAK1, STAT1 and IRF1 signaling
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Sveta, Padmanabhan, Bijaya, Gaire, Yue, Zou, Mohammad M, Uddin, and Ivana, Vancurova
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Gene Expression Regulation, Neoplastic ,Ovarian Neoplasms ,Interferon-gamma ,STAT1 Transcription Factor ,Cell Line, Tumor ,Humans ,Female ,Janus Kinase 1 ,Cell Biology ,Carcinoma, Ovarian Epithelial ,B7-H1 Antigen ,Interferon Regulatory Factor-1 - Abstract
Expression of the immune checkpoint programmed death ligand-1 (PD-L1) is increased in ovarian cancer (OC) and correlates with poor prognosis. Interferon-γ (IFNγ) induces PD-L1 expression in OC cells, resulting in their increased proliferation and tumor growth, but the mechanisms that regulate the PD-L1 expression in OC remain unclear. Here, we show that the IFNγ-induced PD-L1 expression in OC cells is associated with increased levels of STAT1, Tyr-701 pSTAT1 and Ser-727 pSTAT1. Suppression of JAK1 and STAT1 significantly decreases the IFNγ-induced PD-L1 expression in OC cells, and STAT1 overexpression increases the IFNγ-induced PD-L1 expression. In addition, IFNγ induces expression of the transcription factor interferon regulatory factor 1 (IRF1) and IRF1 suppression attenuates the IFNγ-induced gene and protein levels of PD-L1. Chromatin immunoprecipitation results show that IFNγ induces PD-L1 promoter acetylation and recruitment of STAT1, Ser-727 pSTAT1 and IRF1 in OC cells. Together, these findings demonstrate that the IFNγ-induced PD-L1 expression in OC cells is regulated by JAK1, STAT1, and IRF1 signaling, and suggest that targeting the JAK1/ STAT1/IRF1 pathway may provide a leverage to regulate the PD-L1 levels in ovarian cancer.
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- 2022
6. PI3K/AKT/mTOR signaling participates in insulin‐mediated regulation of pathological myopia‐related factors in retinal pigment epithelial cells
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Qiyun Hua, Jin Yang, Li-Bo Xiao, Yun-Qin Li, Junliang Jiang, and Yue Zou
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medicine.medical_treatment ,RPE cells ,Retinal Pigment Epithelium ,Cell morphology ,Phosphatidylinositol 3-Kinases ,medicine ,Insulin ,PI3K/AKT/mTOR ,Humans ,Secretion ,Viability assay ,Protein kinase B ,Pathological myopia ,PI3K/AKT/mTOR pathway ,Retina ,biology ,business.industry ,TOR Serine-Threonine Kinases ,Epithelial Cells ,General Medicine ,RE1-994 ,Cell biology ,Ophthalmology ,Insulin receptor ,medicine.anatomical_structure ,Myopia, Degenerative ,biology.protein ,business ,Proto-Oncogene Proteins c-akt ,Retinal Pigments ,Research Article ,Signal Transduction - Abstract
Background Insulin positively correlates with the length of the eye axis and is increased in the vitreous and serum of patients with pathological myopia (PM). How insulin influences the physiological process of retinal pigment epithelial (RPE) cells in PM remains unclear. This study aimed to explore the effect of insulin on the ultrastructure and function of RPE cells and the role of PI3K/AKT/mTOR signaling involved in the development of PM. Methods The ARPE-19 cells were treated with different concentrations of insulin to analyze the cell morphology, cell viability, the protein level of insulin receptor β, and the mRNA and protein levels of and PM-related factors (TIMP-2, MMP-2, bFGF, and IGF-1). The ultrastructure of APRE-19 cells was also observed after insulin treatment. Besides, the PI3K/AKT/mTOR signaling was studied with or without the PI3K inhibitor LY294002 in ARPE-19 cells. Results Insulin enhanced the cell viability of ARPE-19 cells and caused the endoplasmic reticulum to expand and vesiculate, suggesting increased secretion of growth factors and degeneration in ARPE-19 cells. Furthermore, the insulin receptor β was stimulated with insulin treatment, subsequently, the phosphorylation of AKT and mTOR was positively activated, which was adversely suppressed in the presence of LY294002. The secretion of TIMP-2 and bFGF was significantly decreased, and the secretion of MMP-2 and IGF-1 was highly elevated with insulin treatment depending on the concentration in ARPE-19 cells. Furthermore, the effect of insulin on PM-related proteins was restored with the addition of LY294002. Conclusions Our results indicated that insulin regulated the secretion of PM-related factors via the PI3K/AKT/mTOR signaling pathway in retinal pigment epithelial cells, and thus probably promoted the development of PM through transducing regulation signals from retina to choroid and sclera.
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- 2021
7. ATR prevents Ca2+ overload‐induced necrotic cell death through phosphorylation‐mediated inactivation of PARP1 without DNA damage signaling
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Xiaochun Yu, Yue Zou, Yetunde Makinwa, Hui Wang-Heaton, Phillip R. Musich, Brian M. Cartwright, Nikolozi Shkriabai, Mamuka Kvaratskhelia, Zhengke Li, Benjamin Hilton, Qian Chen, and Shengheng Guan
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0301 basic medicine ,Programmed cell death ,DNA damage ,Poly (ADP-Ribose) Polymerase-1 ,Apoptosis ,Ataxia Telangiectasia Mutated Proteins ,Mitochondrion ,Biochemistry ,PARP1 ,necrosis ,03 medical and health sciences ,chemistry.chemical_compound ,Neuroblastoma ,0302 clinical medicine ,Genetics ,Tumor Cells, Cultured ,Humans ,Kinase activity ,Phosphorylation ,Molecular Biology ,Research Articles ,Kinase ,Chemistry ,Ca2+ overload ,PARP1 phosphorylation ,Cell biology ,Oxidative Stress ,030104 developmental biology ,ATR ,Ionomycin ,Calcium ,Reactive Oxygen Species ,030217 neurology & neurosurgery ,Biotechnology ,Research Article ,DNA Damage ,Signal Transduction - Abstract
Hyperactivation of PARP1 is known to be a major cause of necrotic cell death by depleting NAD+/ATP pools during Ca2+ overload which is associated with many ischemic diseases. However, little is known about how PARP1 hyperactivity is regulated during calcium overload. In this study we show that ATR kinase, well known for its role in DNA damage responses, suppresses ionomycin, glutamate, or quinolinic acid‐induced necrotic death of cells including SH‐SY5Y neuronal cells. We found that the inhibition of necrosis requires the kinase activity of ATR. Specifically, ATR binds to and phosphorylates PARP1 at Ser179 after the ionophore treatments. This site‐specific phosphorylation inactivates PARP1, inhibiting ionophore‐induced necrosis. Strikingly, all of this occurs in the absence of detectable DNA damage and signaling up to 8 hours after ionophore treatment. Furthermore, little AIF was released from mitochondria/cytoplasm for nuclear import, supporting the necrotic type of cell death in the early period of the treatments. Our results reveal a novel ATR‐mediated anti‐necrotic mechanism in the cellular stress response to calcium influx without DNA damage signaling.
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- 2021
8. Novel Biocompatible Polysaccharide-Based Eutectogels with Tunable Rheological, Thermal, and Mechanical Properties: The Role of Water
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Si Qin, Meijie Ren, Yue Zou, Chaoxi Zeng, and Huiping Xia
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Materials science ,Biocompatibility ,Cell Survival ,Pharmaceutical Science ,Biocompatible Materials ,02 engineering and technology ,01 natural sciences ,Article ,Phase Transition ,Analytical Chemistry ,Choline ,lcsh:QD241-441 ,chemistry.chemical_compound ,Differential scanning calorimetry ,lcsh:Organic chemistry ,Drug Discovery ,medicine ,Humans ,Thermal stability ,Physical and Theoretical Chemistry ,Solubility ,Xylitol ,Mechanical Phenomena ,Biological Products ,Shear thinning ,010405 organic chemistry ,Organic Chemistry ,xanthan gum ,Polysaccharides, Bacterial ,Temperature ,Hydrogels ,Hydrogen Bonding ,Hep G2 Cells ,021001 nanoscience & nanotechnology ,natural deep eutectic solvents ,0104 chemical sciences ,Deep eutectic solvent ,Solvent ,chemistry ,Chemical engineering ,Chemistry (miscellaneous) ,Molecular Medicine ,eutectogel ,hydrogel ,0210 nano-technology ,Rheology ,Xanthan gum ,medicine.drug - Abstract
The natural deep eutectic solvent (NADES) is an excellent solvent for insoluble natural products and medicines. Eutectogels formed by gelation of NADESs are interesting materials that deserve attention. In this study, xanthan gum was used as a gelator to gel choline chloride-xylitol with different water contents in virtue of the excellent solubility of choline chloride-xylitol (1:1) to quercetin. We observed that water was critical to the formation of eutectogels. An MTT assay indicated that our eutectogel had excellent biocompatibility as its corresponding hydrogel. According to rheological tests, xanthan gum-based eutectogels had better viscoelastic properties, higher thermal stability, and more defined shear thinning behavior than its corresponding hydrogel. Texture profile analysis showed that eutectogels with less water content had higher hardness and adhesiveness. Meanwhile, Differential scanning calorimeter (DSC) results suggested that the various rheological and texture properties of eutectogels could be attributed to changes in the water state, which was influenced by the hydrogen bonding network of NADES. This biocompatible eutectogel with tunable properties was expected to find applications in novel drug delivery vehicles, which are widely used in the fields of medicine and food.
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- 2020
9. Anticoagulation regimens during pregnancy in patients with mechanical heart valves: a protocol for a systematic review and network meta-analysis
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Zhiying Su, Shiwei He, Jumei Liu, Li Zhao, Huiming Ye, Yue Zou, Juan Li, and Hua Yang
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medicine.medical_specialty ,Network Meta-Analysis ,Subgroup analysis ,Meta-Analysis as Topic ,Pregnancy ,Obstetrics and Gynaecology ,Protocol ,Medicine ,Humans ,mechanical heart valves ,Intensive care medicine ,Randomized Controlled Trials as Topic ,business.industry ,anticoagulation regimens ,Clinical study design ,Pregnancy Complications, Hematologic ,Anticoagulants ,Bayes Theorem ,General Medicine ,Publication bias ,Heart Valves ,Clinical trial ,Regimen ,Systematic review ,Research Design ,Meta-analysis ,Observational study ,Female ,business ,Systematic Reviews as Topic - Abstract
IntroductionPregnancy in patients with mechanical heart valves (MHVs) is associated with high maternal complications and fetal complications.Anticoagulation treatments serve to decrease their venous clotting risk. Although some anticoagulation regimens have been used for patients during pregnancy with MHVs, no one is definitively superior among different regimens in recent studies. For a better understanding of the clinical treatment which anticoagulation regimen is more effective and safer during the pregnancy in patients with MHVs, a Bayesian network meta-analysis is necessary.Methods and analysisThis protocol has been reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols. Related studies until April 2019 will be searched in the following databases: PubMed, Embase,SinoMed and the using the OVID interface to search for evidence-based medicine reviews. A clinical trial registry (www.ClinicalTrials.gov) was also searched for unpublished trials. Both experimental studies (randomised clinical trials) and observational studies (cohort studies, case–control studies and case series studies) will be included in this study. Quality assessment will be conducted using Cochrane Collaboration’s tool or Newcastle-Ottawa Scale based on their study designs. The primary outcomes of interest will be the frequencies of serious maternal and fetal events. The additional outcomes of interest will be adverse maternal events, mode of delivery and adverse fetal events. Pairwise and network meta-analysis will be conducted using R (V.3.4.4, R Foundation for Statistical Computing, Vienna, Austria) and Stata (V.14, StataCorp). The ranking probabilities will be estimated at each possible rank for each anticoagulation regimen using the surface under the cumulative ranking curve. Statistical inconsistency assessment, subgroup analysis, sensitivity analysis and publication bias assessment will be performed.Ethics and disseminationEither ethics approval or patient consent is not necessary, because this study will be based on literature. The results of this study will be published in a peer-reviewed journal.PROSPERO registration numberCRD42019130659
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- 2020
10. Flow Cytometry Analysis of Surface PD-L1 Expression Induced by IFNγ and Romidepsin in Ovarian Cancer Cells
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Sveta, Padmanabhan, Yue, Zou, and Ivana, Vancurova
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Data Analysis ,Gene Expression Regulation, Neoplastic ,Ovarian Neoplasms ,Interferon-gamma ,Cell Line, Tumor ,Depsipeptides ,Cell Membrane ,Humans ,Female ,Cell Separation ,Flow Cytometry ,B7-H1 Antigen - Abstract
Expression of programmed death ligand-1 (PD-L1, CD274) on cancer cells is regulated by interferon-γ (IFNγ) signaling as well as by epigenetic mechanisms. By binding to PD-1 on cytotoxic T cells, PD-L1 inhibits T cell-mediated antitumor responses, resulting in immune escape. This chapter describes analysis of the surface PD-L1 expression in ovarian cancer (OC) cells using flow cytometry (FC). Our data demonstrate that the surface PD-L1 expression in OC cells is induced by IFNγ as well as by the class I histone deacetylase (HDAC) inhibition by romidepsin, suggesting that class I HDAC inhibition might provide a useful strategy to modulate the PD-L1 levels on OC cells.
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- 2020
11. Analysis of PD-L1 Transcriptional Regulation in Ovarian Cancer Cells by Chromatin Immunoprecipitation
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Yue, Zou, Sveta, Padmanabhan, and Ivana, Vancurova
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Ovarian Neoplasms ,Chromatin Immunoprecipitation ,Binding Sites ,Transcription, Genetic ,Cell Culture Techniques ,NF-kappa B ,Real-Time Polymerase Chain Reaction ,B7-H1 Antigen ,DNA-Binding Proteins ,Gene Expression Regulation, Neoplastic ,Interferon-gamma ,Cell Line, Tumor ,Humans ,Female ,Promoter Regions, Genetic ,Protein Binding - Abstract
The immune checkpoint molecule, programmed death ligand 1 (PD-L1; B7-H1, CD274), induces T cell apoptosis and tolerance, thus inhibiting the antitumor immunity. PD-L1 expression is increased in many types of cancer, including ovarian cancer (OC), and correlates with poor prognosis. However, the mechanisms that regulate the PD-L1 expression in cancer cells are incompletely understood. The transcriptional regulation of PD-L1 expression is orchestrated by several transcription factors, including NFκB. The human PD-L1 promoter contains five NFκB-binding sites. Interferon-γ (IFNγ) stimulation of OC cells induces p65, and particularly K314/315 acetylated p65 recruitment to all five NFκB-binding sites in PD-L1 promoter, resulting in increased PD-L1 expression. In this chapter, we describe a protocol that uses chromatin immunoprecipitation (ChIP) to analyze the transcriptional regulation of PD-L1 by measuring recruitment of NFκB p65 and K314/315 acetylated p65 to PD-L1 promoter in human OC cells.
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- 2020
12. Analysis of IFNγ-Induced Migration of Ovarian Cancer Cells
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Bijaya, Gaire, Mohammad M, Uddin, Yue, Zou, and Ivana, Vancurova
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Data Analysis ,Ovarian Neoplasms ,Interferon-gamma ,Wound Healing ,Cell Movement ,Cell Line, Tumor ,Humans ,Female ,Cells, Cultured ,Software ,Cell Proliferation ,Molecular Imaging - Abstract
IFNγ is a pleiotropic cytokine that has both antitumor functions and pro-tumorigenic effects. Recent studies have shown that IFNγ induces expression of the immune checkpoint PD-L1 in ovarian cancer (OC) cells, resulting in their increased proliferation and tumor growth. Here, we tested the hypothesis that IFNγ induces migration of OC cells. Using the scratch wound healing assay, our results demonstrate that IFNγ promotes OC cell migration, thus adding to the complexities of IFNγ pro-tumorigenic mechanisms. This chapter describes analysis of the IFNγ-induced migration of OC cells by the wound healing assay followed by quantification of the obtained images using ImageJ software.
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- 2020
13. Immunoblotting Analysis of Intracellular PD-L1 Levels in Interferon-γ-Treated Ovarian Cancer Cells Stably Transfected with Bcl3 shRNA
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Sveta, Padmanabhan, Yue, Zou, and Ivana, Vancurova
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Ovarian Neoplasms ,Interferon-gamma ,B-Cell Lymphoma 3 Protein ,Cell Line, Tumor ,Immunoblotting ,Gene Expression ,Humans ,Female ,RNA, Small Interfering ,Transfection ,Proto-Oncogene Mas ,B7-H1 Antigen - Abstract
Expression of the immune checkpoint programmed death ligand 1 (PD-L1, CD274) is increased in many types of cancer, including ovarian cancer (OC), but the mechanisms that regulate the PD-L1 expression are not fully understood. In addition to binding to PD-1 on T cells, thus inhibiting T cell-mediated antitumor responses, PD-L1 has also tumor-intrinsic effects that include increased cancer cell survival and proliferation, and that might be in part mediated by the intracellular PD-L1. In this chapter, we describe a protocol for the analysis of the intracellular PD-L1 protein levels in OC cells by immunoblotting. Our results show that interferon-γ (IFNγ) induces the intracellular levels of PD-L1 and the proto-oncogene Bcl3 in OC cells. However, the PD-L1 expression is significantly decreased in OC cells stably transfected with Bcl3 shRNA, demonstrating that the IFNγ-induced PD-L1 expression in OC cells is mediated by Bcl3. These data identify the IFNγ-Bcl3-PD-L1 axis as a novel therapeutic target in OC, and suggest that targeting Bcl3 may provide a novel strategy to regulate the PD-L1 expression, and especially the tumor-intrinsic PD-L1 effects mediated by the intracellular PD-L1 in OC cells.
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- 2020
14. ATM Deficiency Accelerates DNA Damage, Telomere Erosion, and Premature T Cell Aging in HIV-Infected Individuals on Antiretroviral Therapy
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Zheng D. Morrison, Mohamed El Gazzar, Yue Zou, Zhi Q. Yao, Lam Nhat Nguyen, Dechao Cao, Ling Wang, Xindi Dang, Xiao Y. Wu, Juan Zhao, Stella C. Ogbu, Bal Krishna Chand Thakuri, Shunbin Ning, Madison Schank, Zhengke Li, Lam Ngoc Thao Nguyen, Sushant Khanal, and Jonathan P. Moorman
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lcsh:Immunologic diseases. Allergy ,0301 basic medicine ,Senescence ,DNA damage ,DNA repair ,T cell ,T-Lymphocytes ,Immunology ,HIV Infections ,Ataxia Telangiectasia Mutated Proteins ,Biology ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,DNA damage repair ,Immunology and Allergy ,Checkpoint Kinase 2 ,Cellular Senescence ,Original Research ,apoptosis ,HIV ,G2-M DNA damage checkpoint ,Telomere ,3. Good health ,030104 developmental biology ,medicine.anatomical_structure ,MRN complex ,Anti-Retroviral Agents ,T cell homeostasis ,ATM ,Cancer research ,lcsh:RC581-607 ,immune aging ,030215 immunology ,DNA Damage - Abstract
HIV infection leads to a phenomenon of inflammaging, in which chronic inflammation induces an immune aged phenotype, even in individuals on combined antiretroviral therapy (cART) with undetectable viremia. In this study, we investigated T cell homeostasis and telomeric DNA damage and repair machineries in cART-controlled HIV patients at risk for inflammaging. We found a significant depletion of CD4 T cells, which was inversely correlated with the cell apoptosis in virus-suppressed HIV subjects compared to age-matched healthy subjects (HS). In addition, HIV CD4 T cells were prone to DNA damage that extended to chromosome ends—telomeres, leading to accelerated telomere erosion—a hallmark of cell senescence. Mechanistically, the DNA double-strand break (DSB) sensors MRE11, RAD50, and NBS1 (MRN complex) remained intact, but both expression and activity of the DNA damage checkpoint kinase ataxia-telangiectasia mutated (ATM) and its downstream checkpoint kinase 2 (CHK2) were significantly suppressed in HIV CD4 T cells. Consistently, ATM/CHK2 activation, DNA repair, and cellular functions were also impaired in healthy CD4 T cells following ATM knockdown or exposure to the ATM inhibitor KU60019 in vitro, recapitulating the biological effects observed in HIV-derived CD4 T cells in vivo. Importantly, ectopic expression of ATM was essential and sufficient to reduce the DNA damage, apoptosis, and cellular dysfunction in HIV-derived CD4 T cells. These results demonstrate that failure of DSB repair due to ATM deficiency leads to increased DNA damage and renders CD4 T cells prone to senescence and apoptotic death, contributing to CD4 T cell depletion or dysfunction in cART-controlled, latent HIV infection.
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- 2019
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15. IFNγ induces JAK1/STAT1/p65 NFκB-dependent interleukin-8 expression in ovarian cancer cells, resulting in their increased migration
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Bijaya Gaire, Daniel DeLeon, Sveta Padmanabhan, Mohammad M. Uddin, Yue Zou, and Ivana Vancurova
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Ovarian Neoplasms ,Chemokine ,biology ,Chemistry ,medicine.medical_treatment ,Interleukin-8 ,Cell Biology ,medicine.disease ,Biochemistry ,Article ,Interferon-gamma ,STAT1 Transcription Factor ,Immune system ,Cytokine ,biology.protein ,Cancer research ,medicine ,Humans ,Phosphorylation ,Female ,Interleukin 8 ,STAT1 ,Antibody ,Ovarian cancer - Abstract
Interferon-γ (IFNγ) is a pleiotropic cytokine that has a crucial role in immune response and tumor immunity. Because of its anti-tumor effects, IFNγ has been used in cancer treatment. However, IFNγ also has tumor-promoting functions that are less well understood. Here, we show that IFNγ induces expression of the pro-inflammatory and pro-angiogenic chemokine interleukin-8 (IL-8, CXCL8) in ovarian cancer (OC) cells. The IFNγ-induced IL-8 expression is dependent on JAK1, STAT1, and p65 NFκB, and is associated with an increased occupancy of K314/315 acetylated p65 NFκB and Ser-727 phosphorylated STAT1 at the IL-8 promoter. Neutralization of IL-8 using anti-IL-8 antibody reduces IFNγ-induced migration of OC cells, and their invasion ability in 3D spheroids. Together, these findings identify IL-8 as a novel target induced by IFNγ/JAK1/STAT1/p65 NFκB signaling, and indicate that the IFNγ-induced IL-8 contributes to IFNγ pro-tumorigenic effects in ovarian cancer cells.
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- 2021
16. Disruption of Telomere Integrity and DNA Repair Machineries by KML001 Induces T Cell Senescence, Apoptosis, and Cellular Dysfunctions
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Yue Zou, Zhi Q. Yao, Madison Schank, Zheng D. Morrison, Xindi Dang, Mohamed El Gazzar, Bal K Chand Thakuri, Dechao Cao, Lam N Nguyan, Sushant Khanal, Shunbin Ning, Xiao Y. Wu, Jonathan P. Moorman, Juan Zhao, Ling Wang, and Lam Nhat Nguyen
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0301 basic medicine ,Premature aging ,Senescence ,Adult ,CD4-Positive T-Lymphocytes ,Male ,lcsh:Immunologic diseases. Allergy ,Telomerase ,DNA Repair ,DNA damage ,DNA repair ,Arsenites ,T cell ,Immunology ,T cells ,HIV Infections ,Biology ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Immunology and Allergy ,Humans ,DNA damage repair ,Cells, Cultured ,Cellular Senescence ,Original Research ,Aged ,Cell Proliferation ,KML001 ,aging ,apoptosis ,HIV ,Middle Aged ,Telomere ,telomeres ,Hepatitis C ,Sodium Compounds ,Coculture Techniques ,Cell biology ,030104 developmental biology ,medicine.anatomical_structure ,HCV ,Cytokines ,Female ,lcsh:RC581-607 ,Telomeric-Repeat Binding Factor ,030215 immunology ,DNA Damage - Abstract
T cells in chronic viral infections are featured by premature aging with accelerated telomere erosion, but the mechanisms underlying telomere attrition remain unclear. Here, we employed human CD4 T cells treated with KML001 (a telomere-targeting drug) as a model to investigate the role of telomere integrity in remodeling T cell senescence. We demonstrated that KML001 could inhibit cell proliferation, cytokine production, and promote apoptosis via disrupting telomere integrity and DNA repair machineries. Specifically, KML001-treated T cells increased dysfunctional telomere-induced foci (TIF), DNA damage marker γH2AX, and topoisomerase cleavage complex (TOPcc) accumulation, leading to telomere attrition. Mechanistically, KML001 compromised telomere integrity by inhibiting telomeric repeat binding factor 2 (TRF2), telomerase, topoisomerase I and II alpha (Top1/2a), and ataxia telangiectasia mutated (ATM) kinase activities. Importantly, these KML001-induced telomeric DNA damage and T cell senescent phenotype and machineries recapitulated our findings in patients with clinical HCV or HIV infection in that their T cells were also senescent with short telomeres and thus more vulnerable to KML001-induced apoptosis. These results shed new insights on the T cell aging network that is critical and essential in protecting chromosomal telomeres from unwanted DNA damage and securing T cell survival during cell crisis upon genomic insult.
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- 2019
17. Poor Sleep Quality Is Associated with a Higher Risk of Pulmonary tuberculosis in Patients with a Type 2 Diabetes Mellitus Course for More than 5 Years
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Qian Liu, Chunjiang Dong, Caiting Yu, Shanliang Zhao, Limei Sun, Yue Zou, Yufeng Liu, Xiaoli Gao, Xiuping Du, Hong Tian, Boyang Wei, Tingyan Kou, Zhenlei Zhao, Guilan Zhang, Wenshan Lv, and Qiuzhen Wang
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Microbiology (medical) ,Adult ,Male ,medicine.medical_specialty ,China ,Overweight ,Logistic regression ,Risk Factors ,Internal medicine ,Medicine ,Humans ,Risk factor ,Tuberculosis, Pulmonary ,Aged ,business.industry ,Confounding ,Type 2 Diabetes Mellitus ,General Medicine ,Odds ratio ,Middle Aged ,medicine.disease ,Obesity ,Infectious Diseases ,Diabetes Mellitus, Type 2 ,Case-Control Studies ,Multivariate Analysis ,Female ,medicine.symptom ,business ,Sleep ,Body mass index - Abstract
A case-control study was conducted in Shandong from January to December 2017 to explore the relationship between sleep quality and the risk of active pulmonary tuberculosis (PTB). Seventy-nine patients with type 2 diabetes mellitus coincident with newly diagnosed pulmonary tuberculosis (DM-PTB) and 169 age, sex, and DM course frequency-matched controls (DM alone) were enrolled. Univariate and multivariable unconditional logistic regression analyses were conducted. We further conducted subgroup analyses to explore the relationship between sleep quality and PTB risk, including DM course (≤5 and >5 years), age, sex, and the presence of overweight or obesity (body mass index (BMI) > 24 kg/m2). Multivariate logistic regression demonstrated that poor sleep quality had a borderline negative association with the odds of PTB (P = 0.065). Subgroup multivariate analyses showed that poor sleep quality increased the risk of PTB to more than 3 times among patients with a DM course > 5 years (odds ratio 3.31, 95% confidence interval: 1.08-10.13; P = 0.036) after adjusting for potential confounding factors including residential area, educational level, BMI, history of contact with tuberculosis patients, smoking, alcohol consumption, physical exercise, immune status, and frequency of blood glucose monitoring. In conclusion, poor sleep quality is an independent risk factor of PTB among DM patients with a course of > 5 years, which indicates significant epidemiological implications for PTB control.
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- 2019
18. A ratiometric fluorescent nanoprobe based on naphthalimide derivative-functionalized carbon dots for imaging lysosomal formaldehyde in HeLa cells
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Jian-Hua Wang, Yong-Liang Yu, Jia Ye, Shuai Chen, and Guang-Yue Zou
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Chlorpromazine ,Nanoprobe ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,HeLa ,Limit of Detection ,Formaldehyde ,Microscopy ,Quantum Dots ,Humans ,General Materials Science ,Fluorescent Dyes ,Detection limit ,Aqueous solution ,Microscopy, Confocal ,biology ,Chemistry ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Fluorescence ,Carbon ,Endocytosis ,0104 chemical sciences ,Naphthalimides ,Spectrometry, Fluorescence ,Biophysics ,Amine gas treating ,0210 nano-technology ,Lysosomes ,Macromolecule ,HeLa Cells - Abstract
Endogenous formaldehyde (FA) exists in many living cells and in inhomogeneous distribution in organelles. In particular, lysosomes play significant roles in FA generation and the biofunction of living cells. Herein, we developed a new ratiometric fluorescent nanoprobe, based on naphthalimide derivative (ND)-functionalized carbon dots (CDs), for monitoring endogenous FA in lysosomes. The fluorescence intensity (F535) of green-emitting ND at 535 nm serves as the response signal and the fluorescence intensity (F414) of blue-emitting CDs at 414 nm acts as the reference signal. The fluorescence intensity ratio (F535/F414) of the CD-ND probe is linearly correlated with FA concentration within the range of 1-40 μM in aqueous solution, and the detection limit (3σ/slope) is estimated to be 0.34 μM. As for practical application, this nanoprobe is utilized for the ratiometric fluorescence imaging of FA in live cells. Remarkably, this nanoprobe can specifically target and stain the lysosomes and detect exogenous and endogenous FA in HeLa cells. The new FA probe shows a superior lysosomal targeting ability with a Pearson's coefficient of 0.93, which is attributed to the macromolecular size and basic amine group functionalized surface of CD-ND.
- Published
- 2019
19. A novel thyroid hormone receptor isoform, TRβ2-46, promotes SKP2 expression and retinoblastoma cell proliferation
- Author
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Donglai Qi, David Cobrinik, Hardeep Singh, Yue Zou, Zhengke Li, and Binghui Shen
- Subjects
0301 basic medicine ,Gene isoform ,Cell ,medicine.disease_cause ,Biochemistry ,03 medical and health sciences ,Mice ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Protein Isoforms ,Molecular Biology ,S-Phase Kinase-Associated Proteins ,Cell Proliferation ,Gene knockdown ,Thyroid hormone receptor ,030102 biochemistry & molecular biology ,Chemistry ,Cell growth ,Retinoblastoma ,Protein Stability ,Thyroid Hormone Receptors beta ,Cell Biology ,Cell cycle ,medicine.disease ,Cell biology ,Neoplasm Proteins ,030104 developmental biology ,medicine.anatomical_structure ,Accelerated Communications ,Gene Knockdown Techniques ,Carcinogenesis - Abstract
Retinoblastoma is a childhood retinal tumor that develops from cone photoreceptor precursors in response to inactivating RB1 mutations and loss of functional RB protein. The cone precursor's response to RB loss involves cell type-specific signaling circuitry that helps to drive tumorigenesis. One component of the cone precursor circuitry, the thyroid hormone receptor β2 (TRβ2), enables the aberrant proliferation of diverse RB-deficient cells in part by opposing the down-regulation of S-phase kinase-associated protein 2 (SKP2) by the more widely expressed and tumor-suppressive TRβ1. However, it is unclear how TRβ2 opposes TRβ1 to enable SKP2 expression and cell proliferation. Here, we show that in human retinoblastoma cells TRβ2 mRNA encodes two TRβ2 protein isoforms: a predominantly cytoplasmic 54-kDa protein (TRβ2-54) corresponding to the well-characterized full-length murine Trβ2 and an N-terminally truncated and exclusively cytoplasmic 46-kDa protein (TRβ2-46) that starts at Met-79. Whereas TRβ2 knockdown decreased SKP2 expression and impaired retinoblastoma cell cycle progression, re-expression of TRβ2-46 but not TRβ2-54 stabilized SKP2 and restored proliferation to an extent similar to that of ectopic SKP2 restoration. We conclude that TRβ2-46 is an oncogenic thyroid hormone receptor isoform that promotes SKP2 expression and SKP2-dependent retinoblastoma cell proliferation.
- Published
- 2019
20. Epidemiological characteristics of hepatic echinococcosis, concurrent cerebral echinococcosis, and pulmonary echinococcosis in Ganzi County, Sichuan Province, China
- Author
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Yan-Yi Liu, De-Cai Chen, Shi-Yue Zou, Lin-Yong Zhou, Li Ma, and Zhi-Gang Xiu
- Subjects
Male ,Cross-sectional study ,0302 clinical medicine ,Risk Factors ,pulmonary echinococcosis ,Hygiene ,Epidemiology ,Prevalence ,hepatic echinococcosis ,030212 general & internal medicine ,Central Nervous System Cysts ,Echinococcus granulosus ,media_common ,education.field_of_study ,biology ,Neglected Diseases ,General Medicine ,Middle Aged ,Echinococcosis ,030220 oncology & carcinogenesis ,Female ,Research Article ,Adult ,China ,Echinococcosis, Hepatic ,medicine.medical_specialty ,Echinococcosis, Pulmonary ,media_common.quotation_subject ,Population ,Observational Study ,Neurocysticercosis ,Echinococcus multilocularis ,cerebral echinococcosis ,03 medical and health sciences ,Dogs ,Environmental health ,medicine ,Animals ,Humans ,education ,business.industry ,Public health ,medicine.disease ,biology.organism_classification ,Health Literacy ,Cross-Sectional Studies ,Tomography, X-Ray Computed ,business - Abstract
Human echinococcosis has become a major public health problem in most parts of the world. The objective of this article was to study the demographics of patients with hepatic echinococcosis in Ganzi County to elucidate the main risk factors, as well as to report the concurrent prevalence of cerebral echinococcosis and pulmonary echinococcosis. We recruited 195 patients with hepatic echinococcosis from the Datongma area of Ganzi County from January 2018 to November 2018. The patients’ demographics, living environments, supported medical resources, knowledge of echinococcosis prevention and control, and hygienic practices were investigated and analyzed. The prevalence of cerebral echinococcosis and pulmonary echinococcosis were also investigated. The data were analyzed to identify risk factors for human echinococcosis. Our analysis showed that the herding Tibetan population within the 20 to 60 age group, and females, in particular, were at the highest risk of human echinococcosis infection. Having stray dogs around habitations and intimate activities with dogs and livestock were also behavioral risk factors. People with poor health literacy and low educational qualifications had possible risks of infection. In terms of hygiene, not using tap water as the drinking water source and lack of medical staff were significantly correlated with echinococcosis prevalence. Four patients were diagnosed with cerebral echinococcosis. Among them, 1 patient had both cerebral echinococcosis and pulmonary echinococcosis. Possible high-risk factors for echinococcosis were being female, herding population, in the 20 to 60 age group, having stray dogs around habitations, having activities with dogs and livestock, having poor health literacy, having low educational qualifications, and not using tap water as a drinking water source. The detection rate for brain echinococcosis in patients with hepatic echinococcosis was high (2.05%). Effective preventive strategies should be implemented in epidemic areas. Head CT scans should be applied for early detection of cerebral echinococcosis to carry out the treatment.
- Published
- 2020
21. The proto-oncogene Bcl3 induces immune checkpoint PD-L1 expression, mediating proliferation of ovarian cancer cells
- Author
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Yan Zhu, Ales Vancura, Yue Zou, Sveta Padmanabhan, Pengli Bu, Mohammad M. Uddin, and Ivana Vancurova
- Subjects
0301 basic medicine ,Transcription, Genetic ,Apoptosis ,Biochemistry ,Proto-Oncogene Mas ,B7-H1 Antigen ,03 medical and health sciences ,Interferon-gamma ,0302 clinical medicine ,Interferon ,B-Cell Lymphoma 3 Protein ,PD-L1 ,Cell Line, Tumor ,Proto-Oncogene Proteins ,medicine ,Transcriptional regulation ,Humans ,Gene Regulation ,Neutralizing antibody ,Promoter Regions, Genetic ,Molecular Biology ,Cell Proliferation ,biology ,Oncogene ,Chemistry ,Ovary ,Transcription Factor RelA ,Epithelial Cells ,Cell Biology ,Cell Cycle Checkpoints ,medicine.disease ,Antibodies, Neutralizing ,Immune checkpoint ,Gene Expression Regulation, Neoplastic ,030104 developmental biology ,030220 oncology & carcinogenesis ,Cancer cell ,biology.protein ,Cancer research ,Female ,Tumor Escape ,Ovarian cancer ,E1A-Associated p300 Protein ,medicine.drug ,Signal Transduction ,Transcription Factors - Abstract
The proto-oncogene Bcl3 induces survival and proliferation in cancer cells; however, its function and regulation in ovarian cancer (OC) remain unknown. Here, we show that Bcl3 expression is increased in human OC tissues. Surprisingly, however, we found that in addition to promoting survival, proliferation, and migration of OC cells, Bcl3 promotes both constitutive and interferon-γ (IFN)-induced expression of the immune checkpoint molecule PD-L1. The Bcl3 expression in OC cells is further increased by IFN, resulting in increased PD-L1 transcription. The mechanism consists of an IFN-induced, Bcl3- and p300-dependent PD-L1 promoter occupancy by Lys-314/315 acetylated p65 NF-κB. Blocking PD-L1 by neutralizing antibody reduces proliferation of OC cells overexpressing Bcl3, suggesting that the pro-proliferative effect of Bcl3 in OC cells is partly mediated by PD-L1. Together, this work identifies PD-L1 as a novel target of Bcl3, and links Bcl3 to IFNγ signaling and PD-L1-mediated immune escape.
- Published
- 2018
22. Severe hypovitaminosis D in active tuberculosis patients and its predictors
- Author
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Baoli Du, Guofeng Jiang, Mei Dou, Limei Sun, Tingyan Kou, Yue Zou, Lei Han, Qiuzhen Wang, Yan Ma, Yufeng Liu, Evert G. Schouten, Hong Tian, Jiaqi Song, Tongxia Li, and Frans J. Kok
- Subjects
Adult ,Male ,medicine.medical_specialty ,China ,Tuberculosis ,Adolescent ,Fish consumption ,030209 endocrinology & metabolism ,Disease ,Comorbidity ,Severe vitamin D deficiency ,Critical Care and Intensive Care Medicine ,Logistic regression ,Severity of Illness Index ,vitamin D deficiency ,03 medical and health sciences ,Young Adult ,Outdoor activity ,0302 clinical medicine ,Risk Factors ,Diabetes mellitus ,Internal medicine ,medicine ,Vitamin D and neurology ,Prevalence ,Humans ,030212 general & internal medicine ,Life Style ,Aged ,Human Nutrition & Health ,Aged, 80 and over ,Nutrition and Dietetics ,business.industry ,Diabetes ,Humane Voeding & Gezondheid ,Serum 25(OH)D ,Middle Aged ,medicine.disease ,Vitamin D Deficiency ,Diet ,Cross-Sectional Studies ,Immunology ,Female ,business ,Body mass index - Abstract
Background & aims: Tuberculosis (TB) patients have a significant vitamin D deficiency (VDD) endemic, which may be closely related to the onset and progress of the disease. The comorbidity of diabetes (DM) and TB has posed an increasing challenge in recent years. However, the influence of DM on TB and the possible mechanism are still uncertain. We carried out this study to identify the nutritional status of vitamin D (VD) in TB patients in a northern city in China (latitude 36° N) and investigate the possible predictors of severe vitamin D deficiency (SVDD). Methods: A cross-sectional study including 461 active TB patients (192 with and 269 without DM) were randomly selected from Qingdao Chest Hospital from June 2015 to August 2016. We measured serum 25 hydroxyvitamin D [25(OH)D], and investigated the association between sociodemographic, dietary intake, DM, body mass index (BMI), severity of initial TB signs and symptoms (TB score) and VD status. Multivariate logistic regression analysis was used to define the possible predictors of SVDD. Results: The median serum 25(OH)D concentration was 8.50 ng/mL. Of the 461 TB patients included, 383 (83.1%) had VDD [25(OH)D < 20 ng/mL], and 217 (47.1%) had SVDD [25(OH)D < 8 ng/mL]. The variables associated with serum 25(OH)D concentrations were DM, outdoor activity level, TB score and BMI (p < 0.05). Patients with severe TB score had nearly 5 fold higher risk of having SVDD compared with those in mild subgroup [OR (95% CI) = 4.919 (2.644-9.150), p < 0.001]. Low outdoor activity level also increased the odds of SVDD, while DM and high fish consumption showed protect effects. Conclusions: Severe hypovitaminosis D is prevalent in active TB patients, and the main predictors of SVDD were severe TB score, low outdoor activity, inadequate fish consumption. Lowered serum 25(OH)D may be associated with increased risk of TB in DM.
- Published
- 2018
23. Reprint of: XPA is primarily cytoplasmic but is transported into the nucleus upon UV damage in a cell cycle dependent manner
- Author
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Phillip R. Musich, Zhengke Li, Steven M. Shell, and Yue Zou
- Subjects
Cell Nucleus ,endocrine system ,Cytoplasm ,Cell Cycle ,Humans ,Cell Biology ,Molecular Biology ,Biochemistry ,Article ,Cell Line ,Xeroderma Pigmentosum Group A Protein - Abstract
Nucleotide excision repair (NER) in mammalian cells requires the xeroderma pigmentosum group A protein (XPA) as a core factor. Remarkably, XPA and other NER proteins have been detected by chromatin immunoprecipitation at some active promoters, and NER deficiency is reported to influence the activated transcription of selected genes. However, the global influence of XPA on transcription in human cells has not been determined. We analyzed the human transcriptome by RNA sequencing (RNA-Seq). We first confirmed that XPA is confined to the cell nucleus even in the absence of external DNA damage, in contrast to previous reports that XPA is normally resident in the cytoplasm and is imported following DNA damage. We then analyzed four genetically matched human cell line pairs deficient or proficient in XPA. Of the ∼14,000 genes transcribed in each cell line, 325 genes (2%) had a significant XPA-dependent directional change in gene expression that was common to all four pairs (with a false discovery rate of 0.05). These genes were enriched in pathways for the maintenance of mitochondria. Only 27 common genes were different by more than 1.5-fold. The most significant hits were AKR1C1 and AKR1C2, involved in steroid hormone metabolism. AKR1C2 protein was lower in all of the immortalized XPA-deficient cells. Retinoic acid treatment led to modest XPA-dependent activation of some genes with transcription-related functions. We conclude that XPA status does not globally influence human gene transcription. However, XPA significantly influences expression of a small subset of genes important for mitochondrial functions and steroid hormone metabolism. The results may help explain defects in neurological function and sterility in individuals with xeroderma pigmentosum.
- Published
- 2017
24. XPA is primarily cytoplasmic but is transported into the nucleus upon UV damage in a cell cycle dependent manner
- Author
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Zhengke Li, Steven M. Shell, Phillip R. Musich, and Yue Zou
- Subjects
0301 basic medicine ,Cell Nucleus ,Cytoplasm ,Dependent manner ,DNA Repair ,Ultraviolet Rays ,Cell Cycle ,Cell Biology ,Cell cycle ,Biology ,Biochemistry ,Cell biology ,Xeroderma Pigmentosum Group A Protein ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Cell cycle genetics ,medicine ,Humans ,Molecular Biology ,Nucleus ,DNA Damage - Published
- 2017
25. Neurotoxin-Induced DNA Damage is Persistent in SH-SY5Y Cells and LC Neurons
- Author
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Meng-Yang Zhu, Yue Zou, Kui Cui, Yan Wang, and Phillip R. Musich
- Subjects
Adrenergic Neurons ,Benzylamines ,SH-SY5Y ,DNA Repair ,Raphe ,DNA repair ,DNA damage ,General Neuroscience ,Fibroblasts ,Biology ,Toxicology ,Article ,Cell biology ,Biochemistry ,Cell culture ,Cell Line, Tumor ,Humans ,Raphe Nuclei ,Neurotoxin ,Locus coeruleus ,Camptothecin ,Locus Coeruleus ,Raphe nuclei ,Cells, Cultured ,DNA Damage - Abstract
Degeneration of the noradrenergic neurons has been reported in the brain of patients suffering from neurodegenerative diseases. However, their pathological characteristics during the neurodegenerative course and underlying mechanisms remain to be elucidated. In the present study, we used the neurotoxin camptothecin (CPT) to induce the DNA damage response in neuroblastoma SH-SY5Y cells, normal fibroblast cells, and primarily cultured locus coeruleus (LC) and raphe neurons to examine cellular responses and repair capabilities after neurotoxin exposure. To our knowledge, the present study is the first to show that noradrenergic SH-SY5Y cells are more sensitive to CPT-induced DNA damage and deficient in DNA repair, as compared to fibroblast cells. Furthermore, similar to SH-SY5Y cells, primarily cultured LC neurons are more sensitive to CPT-induced DNA damage and show a deficiency in repairing this damage. Moreover, while N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4) exposure also results in DNA damage in cultured LC neurons, neither CPT nor DSP4 induce DNA damage in neuronal cultures from the raphe nuclei. Taken together, noradrenergic SH-SY5Y cells and LC neurons are sensitive to CPT-induced DNA damage and exhibit a repair deficiency, providing a mechanistic explanation for the pathological characteristics of LC degeneration when facing endogenous and environmental DNA-damaging insults in vivo.
- Published
- 2015
26. Progerin sequestration of PCNA promotes replication fork collapse and mislocalization of XPA in laminopathy-related progeroid syndromes
- Author
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Brian M. Cartwright, Hui Tang, Ji Liu, Antonio E. Rusiñol, Benjamin Hilton, Phillip R. Musich, Youjie Wang, Rowdy Jones, Yiyong Liu, Yue Zou, and Maya Breitman
- Subjects
0301 basic medicine ,Genome instability ,endocrine system ,DNA Repair ,DNA damage ,DNA repair ,Apoptosis ,Biochemistry ,Progeroid syndromes ,Histones ,03 medical and health sciences ,0302 clinical medicine ,Progeria ,Proliferating Cell Nuclear Antigen ,Genetics ,medicine ,Humans ,DNA Breaks, Double-Stranded ,RNA, Small Interfering ,Molecular Biology ,Cells, Cultured ,biology ,integumentary system ,Point mutation ,Research ,Fibroblasts ,Progerin ,medicine.disease ,Lamin Type A ,Proliferating cell nuclear antigen ,Cell biology ,Xeroderma Pigmentosum Group A Protein ,Protein Subunits ,Protein Transport ,030104 developmental biology ,Gene Expression Regulation ,030220 oncology & carcinogenesis ,Mutation ,biology.protein ,Biotechnology - Abstract
Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disorder that is caused by a point mutation in the LMNA gene, resulting in production of a truncated farnesylated-prelamin A protein (progerin). We previously reported that XPA mislocalized to the progerin-induced DNA double-strand break (DSB) sites, blocking DSB repair, which led to DSB accumulation, DNA damage responses, and early replication arrest in HGPS. In this study, the XPA mislocalization to DSBs occurred at stalled or collapsed replication forks, concurrent with a significant loss of PCNA at the forks, whereas PCNA efficiently bound to progerin. This PCNA sequestration likely exposed ds-ssDNA junctions at replication forks for XPA binding. Depletion of XPA or progerin each significantly restored PCNA at replication forks. Our results suggest that although PCNA is much more competitive than XPA in binding replication forks, PCNA sequestration by progerin may shift the equilibrium to favor XPA binding. Furthermore, we demonstrated that progerin-induced apoptosis could be rescued by XPA, suggesting that XPA-replication fork binding may prevent apoptosis in HGPS cells. Our results propose a mechanism for progerin-induced genome instability and accelerated replicative senescence in HGPS.-Hilton, B. A., Liu, J., Cartwright, B. M., Liu, Y., Breitman, M., Wang, Y., Jones, R., Tang, H., Rusinol, A., Musich, P. R., Zou, Y. Progerin sequestration of PCNA promotes replication fork collapse and mislocalization of XPA in laminopathy-related progeroid syndromes.
- Published
- 2017
27. Xeroderma Pigmentosa Group A (XPA), Nucleotide Excision Repair and Regulation by ATR in Response to Ultraviolet Irradiation
- Author
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Phillip R. Musich, Zhengke Li, and Yue Zou
- Subjects
0301 basic medicine ,congenital, hereditary, and neonatal diseases and abnormalities ,endocrine system ,Programmed cell death ,DNA Repair ,Ultraviolet Rays ,DNA damage ,Apoptosis ,Ataxia Telangiectasia Mutated Proteins ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,Animals ,Humans ,Genetic Predisposition to Disease ,Gene ,Cell Nucleus ,Xeroderma Pigmentosum ,Kinase ,Cell cycle ,medicine.disease ,Xeroderma Pigmentosum Group A Protein ,Cell biology ,Phenotype ,030104 developmental biology ,chemistry ,030220 oncology & carcinogenesis ,Ataxia-telangiectasia ,Sunlight ,DNA ,DNA Damage ,Signal Transduction ,Nucleotide excision repair - Abstract
The sensitivity of Xeroderma pigmentosa (XP) patients to sunlight has spurred the discovery and genetic and biochemical analysis of the eight XP gene products (XPA-XPG plus XPV) responsible for this condition. These studies also have served to elucidate the nucleotide excision repair (NER) process, especially the critical role played by the XPA protein. More recent studies have shown that NER also involves numerous other proteins normally employed in DNA metabolism and cell cycle regulation. Central among these is ataxia telangiectasia and Rad3-related (ATR), a protein kinase involved in intracellular signaling in response to DNA damage, especially replicative and transcription stresses. This review summarizes recent findings on the interplay between ATR as a DNA damage signaling kinase and as a novel ligand for intrinsic cell death proteins to delay damage-induced apoptosis, and on ATR’s regulation of XPA and the NER process for repair of UV-induced DNA adducts. ATR’s regulatory role in the cytosolic-to-nuclear translocation of XPA will be discussed. In addition, recent findings elucidating a non-NER role for XPA in DNA metabolism and genome stabilization at ds-ssDNA junctions, as exemplified in prematurely aging progeroid cells, also will be reviewed.
- Published
- 2017
28. Histone Deacetylase (HDAC) Inhibition Induces IκB Kinase (IKK)-dependent Interleukin-8/CXCL8 Expression in Ovarian Cancer Cells
- Author
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Ales Vancura, Bipradeb Singha, Yue Zou, Ivana Vancurova, Mohammad M. Uddin, Pengli Bu, and Himavanth R. Gatla
- Subjects
0301 basic medicine ,musculoskeletal diseases ,endocrine system diseases ,Mice, Nude ,Antineoplastic Agents ,Apoptosis ,IκB kinase ,Biology ,Hydroxamic Acids ,Biochemistry ,03 medical and health sciences ,Histone H3 ,0302 clinical medicine ,medicine ,Animals ,Humans ,Interleukin 8 ,Viability assay ,Promoter Regions, Genetic ,Molecular Biology ,Vorinostat ,Ovarian Neoplasms ,Interleukin-8 ,Ovary ,Acetylation ,Molecular Bases of Disease ,Cell Biology ,medicine.disease ,Molecular biology ,I-kappa B Kinase ,Up-Regulation ,Histone Deacetylase Inhibitors ,030104 developmental biology ,030220 oncology & carcinogenesis ,Cancer research ,Female ,Histone deacetylase ,Ovarian cancer ,medicine.drug - Abstract
Overexpression of the pro-angiogenic chemokine IL-8 (CXCL8) is associated with a poor prognosis in several solid tumors, including epithelial ovarian cancer (EOC). Even though histone deacetylase (HDAC) inhibition has shown remarkable antitumor activity in hematological malignancies, it has been less effective in solid tumors, including EOC. Here we report results that may explain the decreased efficiency of HDAC inhibition in EOC, based on our data demonstrating that HDAC inhibition specifically induces expression of IL-8/CXCL8 in SKOV3, CAOV3, and OVCAR3 cells. Suppression or neutralization of vorinostat-induced IL-8/CXCL8 potentiates the vorinostat inhibitory effect on cell viability and proliferation. The IL-8/CXCL8 expression induced by vorinostat in EOC cells is dependent on IκB kinase (IKK) activity and associated with a gene-specific recruitment of IKKβ and IKK-dependent recruitment of p65 NFκB to the IL-8/CXCL8 promoter. In addition, HDAC inhibition induces acetylation of p65 and histone H3 and their IL-8/CXCL8 promoter occupancy. In vivo results demonstrate that combining vorinostat and the IKK inhibitor Bay 117085 significantly reduces tumor growth in nude mice compared with control untreated mice or either drug alone. Mice in the combination group had the lowest IL-8/CXCL8 tumor levels and the lowest tumor expression of the murine neutrophil [7/4] antigen, indicating reduced neutrophil infiltration. Together, our results demonstrate that HDAC inhibition specifically induces IL-8/CXCL8 expression in EOC cells and that the mechanism involves IKK, suggesting that using IKK inhibitors may increase the effectiveness of HDAC inhibitors when treating ovarian cancer and other solid tumors characterized by increased IL-8/CXCL8 expression.
- Published
- 2016
29. Effects of DSP4 on the Noradrenergic Phenotypes and Its Potential Molecular Mechanisms in SH-SY5Y Cells
- Author
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Moises A. Serrano, Jia Zhang, Meng-Yang Zhu, Yue Zou, Phillip R. Musich, and Yan Wang
- Subjects
Benzylamines ,medicine.medical_specialty ,Cell cycle checkpoint ,SH-SY5Y ,DNA damage ,Down-Regulation ,Dopamine beta-Hydroxylase ,Toxicology ,Article ,Norepinephrine ,Adrenergic Agents ,Cell Line, Tumor ,Internal medicine ,medicine ,Humans ,Norepinephrine Plasma Membrane Transport Proteins ,biology ,General Neuroscience ,DNA replication ,Cell Cycle Checkpoints ,Cell cycle ,Cell biology ,Endocrinology ,Norepinephrine transporter ,biology.protein ,DNA Damage ,Signal Transduction ,medicine.drug - Abstract
Dopamine β-hydroxylase (DBH) and norepinephrine (NE) transporter (NET) are the noradrenergic phenotypes for their functional importance to noradrenergic neurons. It is known that in vivo N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4) treatment induces degeneration of noradrenergic terminals by interacting with NET and depleting intracellular NE. However, DSP4’s precise mechanism of action remains unclear. In this study various biochemical approaches were employed to test the hypothesis that DSP4 down-regulates the expression of DBH and NET, and to determine molecular mechanisms that may be involved. The results showed that treatment of SH-SY5Y neuroblastoma cells with DSP4 significantly decreased mRNA and protein levels of DBH and NET. DSP4-induced reduction of DBH mRNA and proteins, as well as NET proteins showed a time- and concentration-dependent manner. Flow cytometric analysis demonstrated that DSP4-treated cells were arrested predominantly in the S-phase, which was reversible. The arrest was confirmed by several DNA damage response markers (phosphorylation of H2AX and p53), suggesting that DSP4 causes replication stress which triggers cell cycle arrest via the S-phase checkpoints. Moreover, the comet assay verified that DSP4 induced single-strand DNA breaks. In summary, the present study demonstrated that DSP4 down-regulates the noradrenergic phenotypes, which may be mediated by its actions on DNA replication, leading to replication stress and cell cycle arrest. These action mechanisms of DSP4 may account for its degenerative consequence after systematic administration for animal models.
- Published
- 2013
30. ATR Plays a Direct Antiapoptotic Role at Mitochondria, which Is Regulated by Prolyl Isomerase Pin1
- Author
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Xiao Zhen Zhou, Brian M. Cartwright, Kun Ping Lu, Hui Wang, Moises A. Serrano, Phillip R. Musich, Benjamin Hilton, Yue Zou, and Zhengke Li
- Subjects
Protein Conformation ,DNA damage ,Cell ,Apoptosis ,Ataxia Telangiectasia Mutated Proteins ,Mitochondrion ,Article ,03 medical and health sciences ,0302 clinical medicine ,Bcl-2-associated X protein ,stomatognathic system ,Cell Line, Tumor ,medicine ,Prolyl isomerase ,Humans ,Kinase activity ,Protein kinase A ,Molecular Biology ,030304 developmental biology ,bcl-2-Associated X Protein ,Peptidylprolyl isomerase ,0303 health sciences ,Binding Sites ,biology ,Kinase ,Cytochromes c ,Cell Biology ,Peptidylprolyl Isomerase ,HCT116 Cells ,Cell biology ,Mitochondria ,NIMA-Interacting Peptidylprolyl Isomerase ,medicine.anatomical_structure ,HEK293 Cells ,Gene Expression Regulation ,Biochemistry ,030220 oncology & carcinogenesis ,biology.protein ,PIN1 ,biological phenomena, cell phenomena, and immunity ,DNA Damage ,BH3 Interacting Domain Death Agonist Protein - Abstract
ATR, a PI3K-like protein kinase, plays a key role in regulating DNA damage responses. Its nuclear checkpoint kinase function is well documented, but little is known about its function outside the nucleus. Here we report that ATR has an antiapoptotic activity at mitochondria in response to UV damage, and this activity is independent of its hallmark checkpoint/kinase activity and partner ATRIP. ATR contains a BH3-like domain that allows ATR-tBid interaction at mitochondria, suppressing cytochrome c release and apoptosis. This mitochondrial activity of ATR is downregulated by Pin1 that isomerizes ATR from cis-isomer to trans-isomer at the phosphorylated Ser428-Pro429 motif. However, UV inactivates Pin1 via DAPK1, stabilizing the pro-survival cis-isomeric ATR. In contrast, nuclear ATR remains in the trans-isoform disregarding UV. This cytoplasmic response of ATR may provide a mechanism for the observed antiapoptotic role of ATR in suppressing carcinogenesis and its inhibition in sensitizing anticancer agents for killing of cancer cells.
- Published
- 2016
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31. DNA-PK, ATM and ATR collaboratively regulate p53–RPA interaction to facilitate homologous recombination DNA repair
- Author
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Steve M. Patrick, Mohan Dangeti, Phillip R. Musich, Moises A. Serrano, Brian M. Cartwright, Yue Zou, Marina Roginskaya, and Zhengke Li
- Subjects
Cancer Research ,DNA damage ,Protein subunit ,Cell Cycle Proteins ,Ataxia Telangiectasia Mutated Proteins ,DNA-Activated Protein Kinase ,Protein Serine-Threonine Kinases ,Biology ,Transfection ,complex mixtures ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Cell Line, Tumor ,Replication Protein A ,Genetics ,Humans ,Phosphorylation ,Molecular Biology ,Replication protein A ,030304 developmental biology ,0303 health sciences ,Tumor Suppressor Proteins ,Recombinational DNA Repair ,Genes, p53 ,Molecular biology ,DNA-Binding Proteins ,Non-homologous end joining ,enzymes and coenzymes (carbohydrates) ,chemistry ,030220 oncology & carcinogenesis ,Tumor Suppressor Protein p53 ,biological phenomena, cell phenomena, and immunity ,Homologous recombination ,Ataxia telangiectasia and Rad3 related ,DNA ,DNA Damage - Abstract
Homologous recombination (HR) and nonhomologous end joining (NHEJ) are two distinct DNA double-stranded break (DSB) repair pathways. Here, we report that DNA-dependent protein kinase (DNA-PK), the core component of NHEJ, partnering with DNA-damage checkpoint kinases ataxia telangiectasia mutated (ATM) and ATM- and Rad3-related (ATR), regulates HR repair of DSBs. The regulation was accomplished through modulation of the p53 and replication protein A (RPA) interaction. We show that upon DNA damage, p53 and RPA were freed from a p53-RPA complex by simultaneous phosphorylations of RPA at the N-terminus of RPA32 subunit by DNA-PK and of p53 at Ser37 and Ser46 in a Chk1/Chk2-independent manner by ATR and ATM, respectively. Neither the phosphorylation of RPA nor of p53 alone could dissociate p53 and RPA. Furthermore, disruption of the release significantly compromised HR repair of DSBs. Our results reveal a mechanism for the crosstalk between HR repair and NHEJ through the co-regulation of p53-RPA interaction by DNA-PK, ATM and ATR.
- Published
- 2012
32. DNA-damage accumulation and replicative arrest in Hutchinson–Gilford progeria syndrome
- Author
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Yue Zou and Phillip R. Musich
- Subjects
Premature aging ,Aging ,congenital, hereditary, and neonatal diseases and abnormalities ,Progeria ,Xeroderma pigmentosum ,integumentary system ,DNA damage ,nutritional and metabolic diseases ,Biology ,medicine.disease ,Progerin ,Biochemistry ,Lamins ,Article ,LMNA ,Cancer research ,medicine ,Animals ,Humans ,Cell aging ,Cellular Senescence ,Lamin ,DNA Damage ,Signal Transduction - Abstract
A common feature of progeria syndromes is a premature aging phenotype and an enhanced accumulation of DNA damage arising from a compromised repair system. HGPS (Hutchinson–Gilford progeria syndrome) is a severe form of progeria in which patients accumulate progerin, a mutant lamin A protein derived from a splicing variant of the lamin A/C gene (LMNA). Progerin causes chromatin perturbations which result in the formation of DSBs (double-strand breaks) and abnormal DDR (DNA-damage response). In the present article, we review recent findings which resolve some mechanistic details of how progerin may disrupt DDR pathways in HGPS cells. We propose that progerin accumulation results in disruption of functions of some replication and repair factors, causing the mislocalization of XPA (xeroderma pigmentosum group A) protein to the replication forks, replication fork stalling and, subsequently, DNA DSBs. The binding of XPA to the stalled forks excludes normal binding by repair proteins, leading to DSB accumulation, which activates ATM (ataxia telangiectasia mutated) and ATR (ATM- and Rad3-related) checkpoints, and arresting cell-cycle progression.
- Published
- 2011
33. Proteasome inhibition induces IKK-dependent interleukin-8 expression in triple negative breast cancer cells: Opportunity for combination therapy
- Author
-
Mohammad M. Uddin, Ivana Vancurova, Yue Zou, Himavanth R. Gatla, and Tamanna Sharma
- Subjects
lcsh:Medicine ,Artificial Gene Amplification and Extension ,Triple Negative Breast Neoplasms ,IκB kinase ,Biochemistry ,Polymerase Chain Reaction ,Receptors, Interleukin-8B ,Receptors, Interleukin-8A ,Bortezomib ,chemistry.chemical_compound ,0302 clinical medicine ,Breast Tumors ,Medicine and Health Sciences ,Cytotoxic T cell ,Small interfering RNAs ,CXC chemokine receptors ,lcsh:Science ,Triple-negative breast cancer ,Multidisciplinary ,Cell Death ,Transcriptional Control ,I-kappa B Kinase ,3. Good health ,Nucleic acids ,Gene Expression Regulation, Neoplastic ,Oncology ,030220 oncology & carcinogenesis ,Drug Therapy, Combination ,Oligopeptides ,Proteasome Inhibitors ,Research Article ,medicine.drug ,Cell Nucleus Shape ,Proteasome Endopeptidase Complex ,Antineoplastic Agents ,Transfection ,Research and Analysis Methods ,03 medical and health sciences ,Cell Line, Tumor ,Breast Cancer ,Genetics ,medicine ,Humans ,Interleukin 8 ,Non-coding RNA ,Molecular Biology Techniques ,Molecular Biology ,Interleukin-8 ,lcsh:R ,Transcription Factor RelA ,Biology and Life Sciences ,Proteins ,Protein Complexes ,Proteasomes ,Cancers and Neoplasms ,Reverse Transcriptase-Polymerase Chain Reaction ,Carfilzomib ,Gene regulation ,chemistry ,Proteasome ,Cancer research ,RNA ,lcsh:Q ,Gene expression ,030215 immunology - Abstract
Triple negative breast cancer (TNBC) cells express increased levels of the pro-inflammatory and pro-angiogenic chemokine interleukin-8 (IL-8, CXCL8), which promotes their proliferation and migration. Because TNBC patients are unresponsive to current targeted therapies, new therapeutic strategies are urgently needed. While proteasome inhibition by bortezomib (BZ) or carfilzomib (CZ) has been effective in treating hematological malignancies, it has been less effective in solid tumors, including TNBC, but the mechanisms are incompletely understood. Here we report that proteasome inhibition significantly increases expression of IL-8, and its receptors CXCR1 and CXCR2, in TNBC cells. Suppression or neutralization of the BZ-induced IL-8 potentiates the BZ cytotoxic and anti-proliferative effect in TNBC cells. The IL-8 expression induced by proteasome inhibition in TNBC cells is mediated by IκB kinase (IKK), increased nuclear accumulation of p65 NFκB, and by IKK-dependent p65 recruitment to IL-8 promoter. Importantly, inhibition of IKK activity significantly decreases proliferation, migration, and invasion of BZ-treated TNBC cells. These data provide the first evidence demonstrating that proteasome inhibition increases the IL-8 signaling in TNBC cells, and suggesting that IKK inhibitors may increase effectiveness of proteasome inhibitors in treating TNBC.
- Published
- 2018
34. Binding of the human nucleotide excision repair proteins XPA and XPC/HR23B to the 5 R -thymine glycol lesion and structure of the cis -(5 R ,6 S ) thymine glycol epimer in the 5′-GTgG-3′ sequence: destabilization of two base pairs at the lesion site
- Author
-
Ashis K. Basu, Marina Roginskaya, Yue Zou, Michael P. Stone, Kyle L. Brown, and Alvin Altamirano
- Subjects
Models, Molecular ,Base pair ,Guanine ,Stereochemistry ,Genome Integrity, Repair and Replication ,Biology ,010402 general chemistry ,01 natural sciences ,Adduct ,03 medical and health sciences ,chemistry.chemical_compound ,Genetics ,Humans ,Base Pairing ,Nuclear Magnetic Resonance, Biomolecular ,030304 developmental biology ,0303 health sciences ,Binding Sites ,Endodeoxyribonucleases ,Base Sequence ,Escherichia coli Proteins ,Stereoisomerism ,DNA ,Base excision repair ,Xeroderma Pigmentosum Group A Protein ,0104 chemical sciences ,Thymine ,DNA-Binding Proteins ,DNA Repair Enzymes ,chemistry ,Biochemistry ,Epimer ,Protons ,DNA Damage ,Nucleotide excision repair - Abstract
The 5R thymine glycol (5R-Tg) DNA lesion exists as a mixture of cis-(5R,6S) and trans-(5R,6R) epimers; these modulate base excision repair. We examine the 7:3 cis-(5R,6S):trans-(5R,6R) mixture of epimers paired opposite adenine in the 5'-GTgG-3' sequence with regard to nucleotide excision repair. Human XPA recognizes the lesion comparably to the C8-dG acetylaminoflourene (AAF) adduct, whereas XPC/HR23B recognition of Tg is superior. 5R-Tg is processed by the Escherichia coli UvrA and UvrABC proteins less efficiently than the C8-dG AAF adduct. For the cis-(5R, 6S) epimer Tg and A are inserted into the helix, remaining in the Watson-Crick alignment. The Tg N3H imine and A N(6) amine protons undergo increased solvent exchange. Stacking between Tg and the 3'-neighbor G*C base pair is disrupted. The solvent accessible surface and T(2) relaxation of Tg increases. Molecular dynamics calculations predict that the axial conformation of the Tg CH(3) group is favored; propeller twisting of the Tg*A pair and hydrogen bonding between Tg OH6 and the N7 atom of the 3'-neighbor guanine alleviate steric clash with the 5'-neighbor base pair. Tg also destabilizes the 5'-neighbor G*C base pair. This may facilitate flipping both base pairs from the helix, enabling XPC/HR23B recognition prior to recruitment of XPA.
- Published
- 2009
35. Checkpoint Kinase ATR Promotes Nucleotide Excision Repair of UV-induced DNA Damage via Physical Interaction with Xeroderma Pigmentosum Group A
- Author
-
Yue Zou, Mamuka Kvaratskhelia, Nikolozi Shkriabai, Zhengke Li, Moises A. Serrano, Chris A. Brosey, Steven M. Shell, Phillip R. Musich, and Walter J. Chazin
- Subjects
endocrine system ,Cell cycle checkpoint ,Xeroderma pigmentosum ,DNA Repair ,Cell Survival ,Ultraviolet Rays ,DNA damage ,DNA repair ,Amino Acid Motifs ,Active Transport, Cell Nucleus ,Cell Cycle Proteins ,Pyrimidine dimer ,Ataxia Telangiectasia Mutated Proteins ,Protein Serine-Threonine Kinases ,Biology ,Biochemistry ,Mass Spectrometry ,Cell Line ,chemistry.chemical_compound ,medicine ,Animals ,Humans ,Point Mutation ,Phosphorylation ,Molecular Biology ,Cell Nucleus ,Point mutation ,Cell Biology ,medicine.disease ,Xeroderma Pigmentosum Group A Protein ,Cell biology ,chemistry ,DNA: Replication, Repair, Recombination, and Chromosome Dynamics ,Cancer research ,DNA ,DNA Damage ,Protein Binding ,Nucleotide excision repair - Abstract
In response to DNA damage, eukaryotic cells activate a series of DNA damage-dependent pathways that serve to arrest cell cycle progression and remove DNA damage. Coordination of cell cycle arrest and damage repair is critical for maintenance of genomic stability. However, this process is still poorly understood. Nucleotide excision repair (NER) and the ATR-dependent cell cycle checkpoint are the major pathways responsible for repair of UV-induced DNA damage. Here we show that ATR physically interacts with the NER factor Xeroderma pigmentosum group A (XPA). Using a mass spectrometry-based protein footprinting method, we found that ATR interacts with a helix-turn-helix motif in the minimal DNA-binding domain of XPA where an ATR phosphorylation site (serine 196) is located. XPA-deficient cells complemented with XPA containing a point mutation of S196A displayed a reduced repair efficiency of cyclobutane pyrimidine dimers as compared with cells complemented with wild-type XPA, although no effect was observed for repair of (6-4) photoproducts. This suggests that the ATR-dependent phosphorylation of XPA may promote NER repair of persistent DNA damage. In addition, a K188A point mutation of XPA that disrupts the ATR-XPA interaction inhibits the nuclear import of XPA after UV irradiation and, thus, significantly reduced DNA repair efficiency. By contrast, the S196A mutation has no effect on XPA nuclear translocation. Taken together, our results suggest that the ATR-XPA interaction mediated by the helix-turn-helix motif of XPA plays an important role in DNA-damage responses to promote cell survival and genomic stability after UV irradiation.
- Published
- 2009
36. Genomic instability and DNA damage responses in progeria arising from defective maturation of prelamin A
- Author
-
Phillip R. Musich and Yue Zou
- Subjects
Genome instability ,congenital, hereditary, and neonatal diseases and abnormalities ,Aging ,Xeroderma pigmentosum ,DNA Repair ,DNA repair ,DNA damage ,XPA ,Review ,Biology ,Genomic Instability ,03 medical and health sciences ,Progeria ,0302 clinical medicine ,medicine ,Animals ,Humans ,Protein Precursors ,030304 developmental biology ,0303 health sciences ,integumentary system ,premature aging ,Nuclear Proteins ,nutritional and metabolic diseases ,DNA double strand breaks ,Cell Biology ,Lamin Type A ,medicine.disease ,Progerin ,Molecular biology ,Hutchinson-Gilford progeria syndrome ,030220 oncology & carcinogenesis ,Lamin A ,DNA damage responses ,Lamin ,Nucleotide excision repair - Abstract
Progeria syndromes have in common a premature aging phenotype and increased genome instability. The susceptibility to DNA damage arises from a compromised repair system, either in the repair proteins themselves or in the DNA damage response pathways. The most severe progerias stem from mutations affecting lamin A production, a filamentous protein of the nuclear lamina. Hutchinson-Gilford progeria syndrome (HGPS) patients are heterozygous for a LMNA gene mutation while Restrictive Dermopathy (RD) individuals have a homozygous deficiency in the processing protease Zmpste24. These mutations generate the mutant lamin A proteins progerin and FC-lamina A, respectively, which cause nuclear deformations and chromatin perturbations. Genome instability is observed even though genome maintenance and repair genes appear normal. The unresolved question is what features of the DNA damage response pathways are deficient in HGPS and RD cells. Here we review and discuss recent findings which resolve some mechanistic details of how the accumulation of progerin/FC-lamin A proteins may disrupt DNA damage response pathways in HGPS and RD cells. As the mutant lamin proteins accumulate they sequester replication and repair factors, leading to stalled replication forks which collapse into DNA double-strand beaks (DSBs). In a reaction unique to HGPS and RD cells these accessible DSB termini bind Xeroderma pigmentosum group A (XPA) protein which excludes normal binding by DNA DSB repair proteins. The bound XPA also signals activation of ATM and ATR, arresting cell cycle progression, leading to arrested growth. In addition, the effective sequestration of XPA at these DSB damage sites makes HGPS and RD cells more sensitive to ultraviolet light and other mutagens normally repaired by the nucleotide excision repair pathway of which XPA is a necessary and specific component.
- Published
- 2009
37. Specific and Efficient Binding of Xeroderma Pigmentosum Complementation Group A to Double-Strand/Single-Strand DNA Junctions with 3‘- and/or 5‘-ssDNA Branches
- Author
-
Thomas M. Harris, Constance M. Harris, Yiyong Liu, Laureen C. Colis, Yue Zou, Steven M. Shell, Ashis K. Basu, Zhengguan Yang, Phillip R. Musich, and Marina Roginskaya
- Subjects
endocrine system ,Xeroderma pigmentosum ,DNA Repair ,DNA repair ,DNA damage ,Molecular Sequence Data ,DNA, Single-Stranded ,Plasma protein binding ,Spodoptera ,Biology ,Biochemistry ,DNA-binding protein ,Article ,Cell Line ,DNA Adducts ,chemistry.chemical_compound ,medicine ,Animals ,Humans ,Replication protein A ,Base Sequence ,medicine.disease ,Molecular biology ,humanities ,Xeroderma Pigmentosum Group A Protein ,DNA-Binding Proteins ,enzymes and coenzymes (carbohydrates) ,chemistry ,Nucleic Acid Conformation ,Baculoviridae ,DNA ,DNA Damage ,Protein Binding ,Nucleotide excision repair - Abstract
Human XPA is an important DNA damage recognition protein in nucleotide excision repair (NER). We previously observed that XPA binds to the DNA lesion as a homodimer [Liu, Y., Liu, Y., Yang, Z., Utzat, C., Wang, G., Basu, A. K., and Zou, Y. (2005) Biochemistry 44, 7361-7368]. Herein we report that XPA recognized undamaged DNA double-strand/single-strand (ds-ssDNA) junctions containing ssDNA branches with binding affinity (Kd = 49.1 +/- 5.1 nM) much higher than its ability to bind to DNA damage. The recognized DNA junction structures include the Y-shape junction (with both 3'- and 5'-ssDNA branches), 3'-overhang junction (with a 3'-ssDNA branch), and 5'-overhang junction (with a 5'-ssDNA branch). Using gel filtration chromatography and gel mobility shift assays, we showed that the highly efficient binding appeared to be carried out by the XPA monomer and that the binding was largely independent of RPA. Furthermore, XPA efficiently bound to six-nucleotide mismatched DNA bubble substrates with or without DNA adducts including C8 guanine adducts of AF, AAF, and AP and the T[6,4]T photoproducts. Using a set of defined DNA substrates with varying degrees of DNA bending, we also found that the XPC-HR23B complex recognized DNA bending, whereas neither XPA nor the XPA-RPA complex could bind to bent DNA. We propose that, besides DNA damage recognition, XPA may also play a novel role in stabilizing, via its high affinity to ds-ssDNA junctions, the DNA strand opening surrounding the lesion for stable formation of preincision NER intermediates. Our results provide a plausible mechanistic interpretation for the indispensable requirement of XPA for both global genome and transcription-coupled repairs. Since ds-ssDNA junctions are common intermediates in many DNA metabolic pathways, the additional potential role of XPA in cellular processes is discussed.
- Published
- 2006
38. DNA damage responses in progeroid syndromes arise from defective maturation of prelamin A
- Author
-
Youjie Wang, Michael S. Sinensky, Antonio E. Rusiñol, Yue Zou, and Yiyong Liu
- Subjects
DNA Replication ,congenital, hereditary, and neonatal diseases and abnormalities ,DNA damage ,Cell Cycle Proteins ,Ataxia Telangiectasia Mutated Proteins ,Protein Serine-Threonine Kinases ,Biology ,Article ,Progeroid syndromes ,Progeria ,medicine ,Farnesyltranstransferase ,Humans ,DNA Breaks, Double-Stranded ,Enzyme Inhibitors ,Protein Precursors ,Cell Nucleus ,integumentary system ,Tumor Suppressor Proteins ,DNA replication ,Nuclear Proteins ,nutritional and metabolic diseases ,Cell Biology ,Fibroblasts ,Lamin Type A ,Progerin ,medicine.disease ,Molecular biology ,Cell biology ,DNA-Binding Proteins ,Skin Abnormalities ,Restrictive dermopathy ,Lamin - Abstract
The genetic diseases Hutchinson-Gilford progeria syndrome (HGPS) and restrictive dermopathy (RD) arise from accumulation of farnesylated prelamin A because of defects in the lamin A maturation pathway. Both of these diseases exhibit symptoms that can be viewed as accelerated aging. The mechanism by which accumulation of farnesylated prelamin A leads to these accelerated aging phenotypes is not understood. Here we present evidence that in HGPS and RD fibroblasts, DNA damage checkpoints are persistently activated because of the compromise in genomic integrity. Inactivation of checkpoint kinases Ataxia-telangiectasia-mutated (ATM) and ATR (ATM- and Rad3-related) in these patient cells can partially overcome their early replication arrest. Treatment of patient cells with a protein farnesyltransferase inhibitor (FTI) did not result in reduction of DNA double-strand breaks and damage checkpoint signaling, although the treatment significantly reversed the aberrant shape of their nuclei. This suggests that DNA damage accumulation and aberrant nuclear morphology are independent phenotypes arising from prelamin A accumulation in these progeroid syndromes. Since DNA damage accumulation is an important contributor to the symptoms of HGPS, our results call into question the possibility of treatment of HGPS with FTIs alone.
- Published
- 2006
39. ATR-dependent checkpoint modulates XPA nuclear import in response to UV irradiation
- Author
-
Yiyong Liu, Xiaoming Wu, Steven M. Shell, and Yue Zou
- Subjects
DNA Replication ,congenital, hereditary, and neonatal diseases and abnormalities ,Cancer Research ,Lung Neoplasms ,Cell cycle checkpoint ,Xeroderma pigmentosum ,DNA Repair ,Ultraviolet Rays ,DNA repair ,DNA damage ,Active Transport, Cell Nucleus ,Fluorescent Antibody Technique ,Cell Cycle Proteins ,Ataxia Telangiectasia Mutated Proteins ,Adenocarcinoma ,Protein Serine-Threonine Kinases ,Biology ,Transfection ,Article ,Ataxia Telangiectasia ,Genetics ,medicine ,Humans ,RNA, Small Interfering ,Molecular Biology ,Cell Nucleus ,Tumor Suppressor Proteins ,Fibroblasts ,Cell cycle ,medicine.disease ,Xeroderma Pigmentosum Group A Protein ,Cell biology ,DNA-Binding Proteins ,Cell nucleus ,medicine.anatomical_structure ,Cancer research ,DNA Damage ,Nucleotide excision repair - Abstract
In response to DNA damage, mammalian cells activate various DNA repair pathways to remove DNA lesions and, meanwhile, halt cell cycle progressions to allow sufficient time for repair. The nucleotide excision repair (NER) and the ATR-dependent cell cycle checkpoint activation are two major cellular responses to DNA damage induced by UV irradiation. However, how these two processes are coordinated in the response is poorly understood. Here we showed that the essential NER factor XPA (xeroderma pigmentosum group A) underwent nuclear accumulation upon UV irradiation, and strikingly, such an event occurred in an ATR (Ataxia-Telangiectasia mutated and RAD3-related)-dependent manner. Either treatment of cells with ATR kinase inhibitors or transfection of cells with small interfering RNA targeting ATR compromised the UV-induced XPA nuclear translocation. Consistently, the ATR-deficient cells displayed no substantial XPA nuclear translocation while the translocation remained intact in ATM (Ataxia-Telangiectasia mutated)-deficient cells in response to UV irradiation. Moreover, we found that ATR is required for the UV-induced nuclear focus formation of XPA. Taken together, our results suggested that the ATR checkpoint pathway may modulate NER activity through the regulation of XPA redistribution in human cells upon UV irradiation.
- Published
- 2006
40. A new structural insight into XPA-DNA interactions
- Author
-
Benjamin Hilton, Steven M. Shell, Nick Shkriabai, Mamuka Kvaratskhelia, Phillip R. Musich, and Yue Zou
- Subjects
Models, Molecular ,lcsh:Life ,lcsh:QR1-502 ,NHS-biotin, N-hydroxysuccinimidobiotin ,Biochemistry ,lcsh:Microbiology ,chemistry.chemical_compound ,ds/ssDNA, double-strand/single-strand DNA ,DNA junction ,0303 health sciences ,Protein footprinting ,030302 biochemistry & molecular biology ,Xeroderma Pigmentosum Group A Protein ,DNA-Binding Proteins ,GGR, global genome repair ,Protein Binding ,endocrine system ,Xeroderma pigmentosum ,HMG-box ,DNA damage ,XPA ,Molecular Sequence Data ,Biophysics ,HGPS, Hutchinson–Gilford progeria syndrome ,Biology ,DNA-binding protein ,S2 ,TCR, transcription-coupled repair ,03 medical and health sciences ,RPA, replication protein A ,NER, nucleotide excision repair ,medicine ,Humans ,Binding site ,DNA-binding domain ,Molecular Biology ,030304 developmental biology ,Original Paper ,Binding Sites ,Base Sequence ,Lysine ,Cell Biology ,DNA ,Q-TOF, quadrupole time-of-flight ,medicine.disease ,nucleotide excision repair ,XPA, Xeroderma pigmentosum group A ,Protein Structure, Tertiary ,lcsh:QH501-531 ,chemistry ,XPA–DNA binding ,DBD, DNA-binding domain ,DTT, dithiothreitol ,Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ,MALDI-TOF, matrix-assisted laser desorption time-of-flight ,Proteolysis ,Nucleic Acid Conformation ,Nucleotide excision repair - Abstract
XPA (xeroderma pigmentosum group A) protein is an essential factor for NER (nucleotide excision repair) which is believed to be involved in DNA damage recognition/verification, NER factor recruiting and stabilization of repair intermediates. Past studies on the structure of XPA have focused primarily on XPA interaction with damaged DNA. However, how XPA interacts with other DNA structures remains unknown though recent evidence suggest that these structures could be important for its roles in both NER and non-NER activities. Previously, we reported that XPA recognizes undamaged DNA ds/ssDNA (double-strand/single-strandDNA) junctions with a binding affinity much higher than its ability to bind bulky DNA damage. To understand how this interaction occurs biochemically we implemented a structural determination of the interaction using a MS-based protein footprinting method and limited proteolysis. By monitoring surface accessibility of XPA lysines to NHS-biotin modification in the free protein and the DNA junction-bound complex we show that XPA physically interacts with the DNA junctions via two lysines, K168 and K179, located in the previously known XPA(98–219) DBD (DNA-binding domain). Importantly, we also uncovered new lysine residues, outside of the known DBD, involved in the binding. We found that residues K221, K222, K224 and K236 in the C-terminal domain are involved in DNA binding. Limited proteolysis analysis of XPA–DNA interactions further confirmed this observation. Structural modelling with these data suggests a clamp-like DBD for the XPA binding to ds/ssDNA junctions. Our results provide a novel structure-function view of XPA–DNA junction interactions.
- Published
- 2014
41. Interaction and colocalization of Rad9/Rad1/Hus1 checkpoint complex with replication protein A in human cells
- Author
-
Xiaoming Wu, Yue Zou, and Steven M. Shell
- Subjects
DNA Replication ,Exonucleases ,Cancer Research ,DNA damage ,Cell Cycle Proteins ,Biology ,complex mixtures ,Article ,chemistry.chemical_compound ,Replication Protein A ,Genetics ,Humans ,RNA, Small Interfering ,Molecular Biology ,Replication protein A ,fungi ,Colocalization ,RNA ,G2-M DNA damage checkpoint ,Cell cycle ,Molecular biology ,Cell biology ,Chromatin ,DNA-Binding Proteins ,Genes, cdc ,enzymes and coenzymes (carbohydrates) ,Gene Expression Regulation ,chemistry ,Schizosaccharomyces pombe Proteins ,biological phenomena, cell phenomena, and immunity ,DNA ,DNA Damage ,HeLa Cells - Abstract
Replication protein A (RPA) is a eukaryotic single-stranded DNA-binding protein consisting of three subunits of 70-kDa, 32-kDa, and 14-kDa (RPA70, RPA32, RPA14, respectively). It is a protein essential for most cellular DNA metabolic pathways. Checkpoint proteins Rad9, Rad1 and Hus1 form a clamp-like complex which plays a central role in the DNA damage-induced checkpoint response. In this report, we presented the evidence that Rad9-Rad1-Hus1 complex directly interacted with RPA in human cells, and this interaction was mediated by the binding of Rad9 protein to both RPA70 and RPA32 subunits. In addition, the cellular interaction of Rad9-Rad1-Hus1 with RPA or hyperphosphorylated RPA was stimulated by UV irradiation or camptothecin treatment in a dose dependent manner. Such treatments also resulted in the co-localization of the nuclear foci formed with the two complexes. Consistently, knockdown of the RPA expression in cells by the small interference RNA (siRNA) blocked the DNA damage-dependent chromatin association of Rad9-Rad1-Hus1, and also inhibited the Rad9-Rad1-Hus1 complex formation. Taken together, our results suggest that Rad9-Rad1-Hus1 and RPA complexes collaboratively function in DNA damage responses, and that the RPA may serve as a regulator for the activity of Rad9-Rad1-Hus1 complex in the cellular checkpoint network.
- Published
- 2005
42. Interactions of human replication protein A with single-stranded DNA adducts
- Author
-
Yiyong Liu, Christopher Utzat, Nicholas E. Geacintov, Yu Liu, Yue Zou, Ashis K. Basu, and Zhengguan Yang
- Subjects
HMG-box ,DNA damage ,DNA repair ,Oligonucleotides ,DNA, Single-Stranded ,Electrophoretic Mobility Shift Assay ,complex mixtures ,Biochemistry ,DNA-binding protein ,DNA Adducts ,chemistry.chemical_compound ,Replication Protein A ,Humans ,Molecular Biology ,Replication protein A ,Molecular Structure ,Oligonucleotide ,Cell Biology ,DNA-Binding Proteins ,enzymes and coenzymes (carbohydrates) ,Spectrometry, Fluorescence ,chemistry ,DNA ,DNA Damage ,Protein Binding ,Research Article ,Nucleotide excision repair - Abstract
Human RPA (replication protein A), a single-stranded DNA-binding protein, is required for many cellular pathways including DNA repair, recombination and replication. However, the role of RPA in nucleotide excision repair remains elusive. In the present study, we have systematically examined the binding of RPA to a battery of well-defined ssDNA (single-stranded DNA) substrates using fluorescence spectroscopy. These substrates contain adducts of (6-4) photoproducts, N-acetyl-2-aminofluorene-, 1-aminopyrene-, BPDE (benzo[a]pyrene diol epoxide)- and fluorescein that are different in many aspects such as molecular structure and size, DNA disruption mode (e.g. base stacking or non-stacking), as well as chemical properties. Our results showed that RPA has a lower binding affinity for damaged ssDNA than for non-damaged ssDNA and that the affinity of RPA for damaged ssDNA depends on the type of adduct. Interestingly, the bulkier lesions have a greater effect. With a fluorescent base-stacking bulky adduct, (+)-cis-anti-BPDE-dG, we demonstrated that, on binding of RPA, the fluorescence of BPDE-ssDNA was significantly enhanced by up to 8–9-fold. This indicated that the stacking between the BPDE adduct and its neighbouring ssDNA bases had been disrupted and there was a lack of substantial direct contacts between the protein residues and the lesion itself. For RPA interaction with short damaged ssDNA, we propose that, on RPA binding, the modified base of ssDNA is looped out from the surface of the protein, permitting proper contacts of RPA with the remaining unmodified bases.
- Published
- 2005
43. Mass Spectrometric Identification of Lysines Involved in the Interaction of Human Replication Protein A with Single-Stranded DNA
- Author
-
Mamuka Kvaratskhelia, Yue Zou, Steven M. Shell, and Sonja Hess
- Subjects
HMG-box ,DNA damage ,Molecular Sequence Data ,DNA, Single-Stranded ,complex mixtures ,Biochemistry ,DNA-binding protein ,Article ,Mass Spectrometry ,Single-stranded binding protein ,chemistry.chemical_compound ,Replication Protein A ,Humans ,Amino Acid Sequence ,Replication protein A ,Sequence Homology, Amino Acid ,biology ,Protein footprinting ,Lysine ,Binding protein ,DNA-Binding Proteins ,enzymes and coenzymes (carbohydrates) ,chemistry ,biology.protein ,Electrophoresis, Polyacrylamide Gel ,DNA ,Protein Binding - Abstract
Human replication protein A (hRPA), a heterotrimeric single-stranded DNA (ssDNA) binding protein, is required for many cellular pathways including DNA damage repair, recombination, and replication as well as the ATR-mediated DNA damage response. While extensive effort has been devoted to understanding the structural relationships between RPA and ssDNA, information is currently limited to the RPA domains, the trimerization core, and a partial cocrystal structure. In this work, we employed a mass spectrometric protein footprinting method of single amino acid resolution to investigate the interactions of the entire heterotrimeric hRPA with ssDNA. In particular, we monitored surface accessibility of RPA lysines with NHS-biotin modification in the contexts of the free protein and the nucleoprotein complex. Our results not only indicated excellent agreement with the available crystal structure data for RPA70 DBD-AB-ssDNA complex but also revealed new protein contacts in the nucleoprotein complex. In addition to two residues, K263 and K343 of p70, previously identified by cocrystallography as direct DNA contacts, we observed protection of five additional lysines (K183, K259, K489, K577, and K588 of p70) upon ssDNA binding to RPA. Three residues, K489, K577, and K588, are located in ssDNA binding domain C and are likely to establish the direct contacts with cognate DNA. In contrast, no ssDNA-contacting lysines were identified in DBD-D. In addition, two lysines, K183 and K259, are positioned outside the putative ssDNA binding cleft. We propose that the protection of these lysines could result from the RPA interdomain structural reorganization induced by ssDNA binding.
- Published
- 2004
44. Dimerization of Human XPA and Formation of XPA2−RPA Protein Complex
- Author
-
Leslie Y. Mao, Yue Zou, Yang Liu, Zheng guan Yang, and Jian-Ting Zhang
- Subjects
DNA Replication ,endocrine system ,DNA Repair ,Macromolecular Substances ,DNA repair ,DNA damage ,Dimer ,Plasma protein binding ,Spodoptera ,Biochemistry ,Article ,chemistry.chemical_compound ,Replication Protein A ,Escherichia coli ,Animals ,Humans ,Replication protein A ,Fluorocarbons ,Molecular mass ,Chemistry ,DNA replication ,Recombinant Proteins ,Xeroderma Pigmentosum Group A Protein ,DNA-Binding Proteins ,Molecular Weight ,Spectrometry, Fluorescence ,Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ,Chromatography, Gel ,Electrophoresis, Polyacrylamide Gel ,Caprylates ,Dimerization ,Protein Processing, Post-Translational ,Protein Binding ,Nucleotide excision repair - Abstract
XPA plays an important role in the DNA damage recognition during human nucleotide excision repair. Here we report that the XPA is a homodimer either in the free state or as a complex with human RPA in solution under normal conditions. The human XPA protein purified from baculovirus-infected sf21 insect cells has a molecular mass of 36 317 Da, as determined by mass spectroscopy. However, the apparent molecular mass of XPA determined by the native gel filtration chromatography was about 71 kDa, suggesting that XPA is a dimer. This observation was supported by a native PFO-PAGE and fluorescence spectroscopy analysis. XPA formed a dimer (XPA2) in a broad range of XPA and NaCl concentrations, and the dimerization was not due to the disulfide bond formation. Furthermore, a titration analysis of the binding of XPA to the human RPA indicated that it was the XPA2 that formed the complex with RPA. Finally, the difference between the mass spectrometric and the calculated masses of XPA implies that the protein contains posttranslational modifications. Taken together, our data suggest that the dimerization of XPA may play an important role in the DNA damage recognition of nucleotide excision repair.
- Published
- 2002
45. Administering aspirin, rivaroxaban and low-molecular-weight heparin to prevent deep venous thrombosis after total knee arthroplasty
- Author
-
Shaoqi Tian, Kang Sun, Yue Zou, and Yuanhe Wang
- Subjects
Male ,medicine.medical_specialty ,medicine.drug_class ,medicine.medical_treatment ,Deep vein ,Morpholines ,Low molecular weight heparin ,Thiophenes ,Rivaroxaban ,medicine ,Humans ,Prospective Studies ,Arthroplasty, Replacement, Knee ,Aged ,Aged, 80 and over ,Venous Thrombosis ,Aspirin ,business.industry ,Hematology ,General Medicine ,Heparin ,Heparin, Low-Molecular-Weight ,Middle Aged ,medicine.disease ,Thrombosis ,Arthroplasty ,Surgery ,Venous thrombosis ,medicine.anatomical_structure ,Anesthesia ,Female ,business ,medicine.drug - Abstract
This study aimed to compare the efficacy and safety of aspirin, rivaroxaban and low-molecular-weight heparin (LMWH) for post total knee arthroplasty (TKA) deep vein thrombosis (DVT) prophylaxis. Between July 2011 and July 2013, a prospective randomized controlled trial was performed on 324 patients with osteoarthritis who underwent primary unilateral TKA. Twelve hours after the surgery, Group A was given oral rivaroxaban at a dose of 10 mg/day. Group B was given subcutaneous LMWH at a dose of 4000 AxaIU (0.4 ml)/day and Group C was given oral aspirin at a dose of 100 mg/day. All three groups were treated for 14 days, and all of the patients were followed for 4 weeks. The incidence of DVT, dominant/hidden blood loss, the incidence of wound complications and the incidence of subcutaneous ecchymosis in the affected extremities were compared between the three groups. The incidence of DVT was lower in Group A compared with the other two groups [3 (2.94%) vs. 14 (12.50%), P = 0.029; 3 (2.94%) vs. 18 (16.36%), P = 0.017]. However, hidden blood loss [1.71 (1.19-2.97) vs. 1.18 (0.77-2.31), P = 0.009; 1.71 (1.19-2.97) vs. 1.30 (0.61-2.43), P = 0.004] and wound complications [5 (4.90) vs. 3 (2.67), P = 0.027; 5 (4.90) vs. 2 (1.82), P = 0.014] were more common in Group A than in the other groups. There were no significant differences between Group B and Group C in the incidence of DVT [14 (12.50%) vs. 18 (16.36%), P = 0.831], hidden blood loss [1.18 (0.77-2.31) vs. 1.30 (0.61-2.43), P = 0.327] or wound complications [3 (2.67) vs. 2 (1.82), P = 0.209]. No significant differences in the incidence of limb swelling were found between the three groups [38 (37.25%) vs. 28 (25.00%) vs. 24 (21.82%), P = 0.247]. Group A had a higher incidence of subcutaneous ecchymosis in the affected extremities than Group C [74 (72.55%) vs. 54 (49.09%), P = 0.039], but there were no significant differences between Groups A and B [74 (72.55%) vs. 62 (55.36%), P = 0.193] or between Groups B and C [62 (55.36%) vs. 54 (49.09%), P = 0.427]. Rivaroxaban has a positive anticoagulation effect but leads to increases in both postoperative blood loss and wound complications in patients. Hence, clinicians using rivaroxaban for anticoagulant therapy should closely monitor the changes in the hemoglobin level and wound healing and promptly supplement blood volume and provide other symptomatic and supportive treatments. No significant difference in post-TKA DVT prophylaxis was found between aspirin and LMWH, and the former can be used as part of a multimodal anticoagulation therapy.
- Published
- 2014
46. Emergency scenario of fentanyl induced faciocervical rigidity and complete upper airway obstruction during anesthesia induction
- Author
-
Xiaowen, Liu, Yue, Zou, Jing, Zhao, and Yuguang, Huang
- Subjects
Airway Obstruction ,Analgesics, Opioid ,Fentanyl ,Male ,Humans ,Anesthesia, General ,Aged ,Muscle Rigidity - Published
- 2014
47. Butadiene-induced Intrastrand DNA Cross-links: A Possible Role in Deletion Mutagenesis
- Author
-
Constance M. Harris, Bennett Van Houten, J. Russ Carmical, Agnieszka Kowalczyk, R. Stephen Lloyd, Yue Zou, Lubomir V. Nechev, and Thomas M. Harris
- Subjects
DNA, Complementary ,Guanine ,Molecular Sequence Data ,Oligonucleotides ,Biochemistry ,DNA Adducts ,chemistry.chemical_compound ,Bacterial Proteins ,Butadienes ,Escherichia coli ,Humans ,Molecular Biology ,Chromatography, High Pressure Liquid ,Polymerase ,Adenosine Triphosphatases ,Base Sequence ,biology ,Escherichia coli Proteins ,DNA replication ,Nucleic Acid Hybridization ,Stereoisomerism ,DNA ,Cell Biology ,Transfection ,Molecular biology ,Deletion Mutagenesis ,DNA-Binding Proteins ,Cross-Linking Reagents ,Genes, ras ,chemistry ,Mutagenesis ,Duplex (building) ,biology.protein ,Epoxy Compounds ,Gene Deletion ,Mutagens ,Nucleotide excision repair - Abstract
To initiate studies designed to identify the mutagenic spectrum associated with butadiene diepoxide-induced N(2)-N(2) guanine intrastrand cross-links, site specifically adducted oligodeoxynucleotides were synthesized in which the adducted bases were centrally located within the context of the human ras 12 codon. The two stereospecifically modified DNAs and the corresponding unmodified DNA were ligated into a single-stranded M13mp7L2 vector and transfected into Escherichia coli. Both stereoisomeric forms (R, R and S,S) of the DNA cross-links resulted in very severely decreased plaque-forming ability, along with an increased mutagenic frequency for both single base substitutions and deletions compared with unadducted DNAs, with the S,S stereoisomer being the most mutagenic. Consistent with decreased plaque formation, in vitro replication of DNA templates containing the cross-links by the three major E. coli polymerases revealed replication blockage by both stereoisomeric forms of the cross-links. The same DNAs that were used for replication studies were also assembled into duplex DNAs and tested as substrates for the initiation of nucleotide excision repair by the E. coli UvrABC complex. UvrABC incised linear substrates containing these intrastrand cross-links with low efficiency, suggesting that these lesions may be inefficiently repaired by the nucleotide excision repair system.
- Published
- 2000
48. PKA-mediated phosphorylation of ATR promotes recruitment of XPA to UV-induced DNA damage
- Author
-
Stuart G, Jarrett, Erin M Wolf, Horrell, Perry A, Christian, Jillian C, Vanover, Mary C, Boulanger, Yue, Zou, and John A, D'Orazio
- Subjects
DNA Repair ,Pigmentation ,Ultraviolet Rays ,Ataxia Telangiectasia Mutated Proteins ,Cyclic AMP-Dependent Protein Kinases ,Article ,Xeroderma Pigmentosum Group A Protein ,DNA-Binding Proteins ,Mice, Inbred C57BL ,Mice ,HEK293 Cells ,Mutagenesis ,Cell Line, Tumor ,MCF-7 Cells ,Animals ,Humans ,RNA Interference ,Phosphorylation ,RNA, Small Interfering ,Protein Processing, Post-Translational ,Receptor, Melanocortin, Type 1 ,DNA Damage ,Signal Transduction - Abstract
The melanocortin 1 receptor (MC1R), which signals through cAMP, is a melanocytic transmembrane receptor involved in pigmentation, adaptive tanning, and melanoma resistance. We report MC1R-mediated or pharmacologically-induced cAMP signaling promotes nucleotide excision repair (NER) in a cAMP-dependent protein kinase A (PKA)-dependent manner. PKA directly phosphorylates ataxia telangiectasia and Rad3-related protein (ATR) at Ser435, which actively recruits the key NER protein xeroderma pigmentosum complementation group A (XPA) to sites of nuclear UV photodamage, accelerating clearance of UV-induced photolesions and reducing mutagenesis. Loss of Ser435 within ATR prevents PKA-mediated ATR phosphorylation, disrupts ATR-XPA binding, delays recruitment of XPA to UV-damaged DNA, and elevates UV-induced mutagenesis. This study mechanistically links cAMP-PKA signaling to NER and illustrates potential benefits of cAMP pharmacological rescue to reduce UV mutagenesis in MC1R-defective, melanoma-susceptible individuals.
- Published
- 2013
49. UV-induced nuclear import of XPA is mediated by importin-α4 in an ATR-dependent manner
- Author
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Yue Zou, Phillip R. Musich, Zhengke Li, Brian M. Cartwright, and Hui Wang
- Subjects
alpha Karyopherins ,Small interfering RNA ,endocrine system ,Xeroderma pigmentosum ,animal structures ,Ultraviolet Rays ,DNA damage ,Immunoprecipitation ,Nuclear Localization Signals ,Biophysics ,Active Transport, Cell Nucleus ,DNA repair ,lcsh:Medicine ,Ataxia Telangiectasia Mutated Proteins ,Importin ,Biology ,Biochemistry ,Models, Biological ,environment and public health ,Cell Line ,03 medical and health sciences ,Molecular cell biology ,0302 clinical medicine ,GTP-Binding Proteins ,medicine ,Humans ,lcsh:Science ,Cellular Stress Responses ,030304 developmental biology ,Cell Nucleus ,0303 health sciences ,Multidisciplinary ,Physics ,lcsh:R ,DNA ,medicine.disease ,Molecular biology ,Recombinant Proteins ,Xeroderma Pigmentosum Group A Protein ,Nucleic acids ,Gene Knockdown Techniques ,030220 oncology & carcinogenesis ,lcsh:Q ,Nuclear transport ,Nuclear localization sequence ,Research Article ,Protein Binding ,Nucleotide excision repair - Abstract
Xeroderma pigmentosum Group A (XPA) is a crucial factor in mammalian nucleotide excision repair (NER) and nuclear import of XPA from the cytoplasm for NER is regulated in cellular DNA damage responses in S-phase. In this study, experiments were carried out to determine the transport mechanisms that are responsible for the UV (ultraviolet)-induced nuclear import of XPA. We found that, in addition to the nuclear localization signal (NLS) of XPA, importin-α4 or/and importin-α7 are required for the XPA nuclear import. Further investigation indicated that, importin-α4 and importin-α7 directly interacted with XPA in cells. Interestingly, the binding of importin-α4 to XPA was dependent on UV-irradiation, while the binding of importin-α7 was not, suggesting a role for importin-α7 in nuclear translocation of XPA in the absence of DNA damage, perhaps with specificity to certain non-S-phases of the cell-cycle. Consistent with the previous report of a dependence of UV-induced XPA nuclear import on ataxia telangiectasia and Rad3-related protein (ATR) in S-phase, knockdown of ATR reduced the amount of XPA interacting with importin-α4. In contrast, the GTPase XPA binding protein 1 (XAB1), previously proposed to be required for XPA nuclear import, showed no effect on the nuclear import of XPA in our siRNA knockdown analysis. In conclusion, our results suggest that upon DNA damage transport adaptor importin-α4 imports XPA into the nucleus in an ATR-dependent manner, while XAB1 has no role in this process. In addition, these findings reveal a potential new therapeutic target for the sensitization of cancer cells to chemotherapy.
- Published
- 2013
50. [Interference of hexavalent chromium on VDAC1 mRNA expression or ATP level and their potential association]
- Author
-
Yuan, Yang, Yue, Zou, Peng, Li, Lei, Luo, Lu, Dai, and Caigao, Zhong
- Subjects
Chromium ,Adenosine Triphosphate ,Voltage-Dependent Anion Channel 1 ,Hepatocytes ,Humans ,RNA, Messenger - Abstract
To explore the interference of hexavalent chromium-Cr(VI) on voltage-dependent anion channel (VDAC1) mRNA expression and intracellular adenosine triphosphate (ATP) level in cells and their potential association.Cultured L-02 hepatocytes were treated with 2, 4, 8, 16 and 32 micromol/L of Cr(VI) for 12, 24 and 36 hours (h). The expression of VDAC1 mRNA was measured by reverse transcription quantitative polymerase chain reaction (RT-qPCR), whereas the levels of intracellular ATP was determined by an ATP-specific bioluminescence assay.(1) The expression of VDAC1 mRNA in cells of treated groups was less than that of control group at 12h, and then showed slight increase at 24h, and increased significantly after 36 h of treatment. (2) After being treated by Cr(VI) for 12 h, ATP level in cells increased, especially in higher dose groups, and the ATP level then decreased significantly at 24h except in the lowest dosage (2 micromol/L) group, and increased again at 36h in 2 micromol/L and 4 micromol/L groups, but the ATP level in 8, 16 and 32 micromol/L groups remained less than that in the control group. (3) Correlation analysis showed a moderate negative relationship between VDAC1 mRNA expression and intracellular ATP level during Cr (VI) treatment (r = -0.604, P0.05).The interference of Cr(VI) on ATP level was associated with abnormal expression of VDAC1 mRNA, over-expression of VDAC1 mRNA may be one of molecular mechanisms for the decrease of ATP level induced by heavy metal-Cr(VI).
- Published
- 2012
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