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Despite certain overlapping clinical presentations, the two human neurodegenerative diseases pantothenate kinase-associated neurodegeneration (PKAN) and Parkinson disease (PD) have distinct genetic etiologies. During our work using Drosophila to study PKAN and PINK1-related PD, we found some common mitochondrial abnormalities in these two disease models, suggesting a potential link in pathogenesis between them. When we delve into their underlying mechanisms, mitochondrial quality control (MQC) stands at the crossroads. While overwhelming evidence suggests that mitochondrial dysfunction plays a role in the pathogenesis of many human neurodegenerative diseases, mitochondrial function is particularly important for PKAN and PD (some inherited PD cases) foretold by the nature of their causative genes. PKAN is caused by mutations in PANK2 (pantothenate kinase 2), the only PANK localized to mitochondria among the four human PANK isoforms. PANKs catalyze the initial step of de novo coenzyme A (CoA) synthesis. PKAN patients and disease models display disturbed mitochondrial functions, but its exact mechanism has not been clearly determined. Usually, damaged mitochondria are surveyed and eliminated by the MQC pathway. Two genes that have been found critical for PD, PINK1 (PTEN induced kinase 1) and PRKN (parkin RBR E3 ubiquitin protein ligase), are positioned at the center of MQC. If the MQC is normal, malfunctional mitochondria will usually be efficiently repaired. Thus, the accumulation of mitochondrial dysfunction in PKAN implies that its MQC mechanism is impaired. The question is, how? In a recent published work, we attempted to answer this question.

Stimulator of IFN genes type I (STING-Type I) IFN signaling in myeloid cells plays a critical role in effective antitumor immune responses, but STING agonists as monotherapy have shown limited efficacy in clinical trials. The mechanisms that downregulate STING signaling are not fully understood. Here, we report that protein phosphatase 2A (PP2A), with its specific B regulatory subunit Striatin 4 (STRN4), negatively regulated STING-Type I IFN in macrophages. Mice with macrophage PP2A deficiency exhibited reduced tumor progression. The tumor microenvironment showed decreased immunosuppressive and increased IFN-activated macrophages and CD8+ T cells. Mechanistically, we demonstrated that Hippo kinase MST1/2 was required for STING activation. STING agonists induced dissociation of PP2A from MST1/2 in normal macrophages, but not in tumor conditioned macrophages. Furthermore, our data showed that STRN4 mediated PP2A binding to and dephosphorylation of Hippo kinase MST1/2, resulting in stabilization of YAP/TAZ to antagonize STING activation. In human patients with glioblastoma (GBM), YAP/TAZ was highly expressed in tumor-associated macrophages but not in nontumor macrophages. We also demonstrated that PP2A/STRN4 deficiency in macrophages reduced YAP/TAZ expression and sensitized tumor-conditioned macrophages to STING stimulation. In summary, we demonstrated that PP2A/STRN4-YAP/TAZ has, in our opinion, been an unappreciated mechanism that mediates immunosuppression in tumor-associated macrophages, and targeting the PP2A/STRN4-YAP/TAZ axis can sensitize tumors to immunotherapy.

As a multi-functional cellular organelle, mitochondrial metabolic reprogramming is well recognized as a hallmark of cancer. The center of mitochondrial metabolism is oxidative phosphorylation (OXPHOS), in which cells use enzymes to oxidize nutrients, thereby converting the chemical energy to the biological energy currency ATPs. OXPHOS also creates the mitochondrial membrane potential and serve as the driving force of other mitochondrial metabolic pathways and experiences significant reshape in the different stages of tumor progression. In this minireview, we reviewed the major mitochondrial pathways that are connected to OXPHOS and are affected in cancer cells. In addition, we summarized the function of novel bio-active molecules targeting mitochondrial metabolic processes such as OXPHOS, mitochondrial membrane potential and mitochondrial dynamics. These molecules exhibit intriguing preclinical and clinical results and have been proven to be promising antitumor candidates in recent studies.

Purpose Recent clinical trials with agents targeting immune checkpoint pathway have emerged as an important therapeutic approach for a broad range of cancer types. Resveratrol has been shown to possess cancer preventive and therapeutic effects and has potential to be chemotherapeutic agent/adjuvant. Here, we assessed the effect of resveratrol on immune checkpoint pathways. Methods The expression patterns of Wnt components and PD-L1 were examined by Western blot, Chromatin immunoprecipitation (ChIP) was used for analysis of DNA–protein interaction, the promoter activity was determined by luciferase reporter assay, apoptosis was analyzed by flow cytometry and the ability of the resveratrol to modulate T cell function was assessed in a co-culture system. Results Although the dose-, and cell-type dependent effects of resveratrol on PD-L1 expression have been reported, we show here that resveratrol dose-dependently upregulates PD-L1 expression at the range of pharmacologic-achievable concentrations in lung cancer cells and that is essential for suppression of T-cell-mediated immune response. We also found that Wnt pathway is critical for mediating resveratrol-induced PD-L1 upregulation. Mechanistically, resveratrol activates SirT1 deacetylase to deacetylate and stabilize transcriptional factor Snail. Snail in turn inhibits transcription of Axin2, which leads in disassembly of destruction complex and enhanced binding of β-catenin/TCF to PD-L1 promoter. Conclusion We conclude that resveratrol is capable to suppress anti-tumor immunity by controlling mainly PD-L1 expression. This finding will extend the understanding of resveratrol in regulation of tumor immunity and is relevant to the debate on resveratrol supplements for lung cancer patients.

Background Metabolic reprogramming contributes significantly to tumor development and is tightly linked to drug resistance. The chemotherapeutic agent etoposide (VP-16) has been used clinically in the treatment of lung cancer but possess different sensitivity and efficacy towards SCLC and NSCLC. Here, we assessed the impact of etoposide on glycolytic metabolism in SCLC and NSCLC cell lines and investigated the role of metabolic rewiring in mediating etoposide resistance. Methods glycolytic differences of drug-treated cancer cells were determined by extracellular acidification rate (ECAR), glucose consumption, lactate production and western blot. DNA damage was evaluated by the comet assay and western blot. Chemoresistant cancer cells were analyzed by viability, apoptosis and western blot. Chromatin immunoprecipitation (ChIP) was used for analysis of DNA-protein interaction. Results Here we showed that exposure to chemotherapeutic drug etoposide induces an exacerbation of ROS production which activates HIF-1α-mediated the metabolic reprogramming toward increased glycolysis and lactate production in non-small cell lung cancer (NSCLC). We identified lactic acidosis as the key that confers multidrug resistance through upregulation of multidrug resistance-associated protein 1 (MRP1, encoded by ABCC1), a member of ATP-binding cassette (ABC) transporter family. Mechanistically, lactic acid coordinates TGF-β1/Snail and TAZ/AP-1 pathway to induce formation of Snail/TAZ/AP-1 complex at the MRP1/ABCC1 promoter. Induction of MRP1 expression inhibits genotoxic and apoptotic effects of chemotherapeutic drugs by increasing drug efflux. Furthermore, titration of lactic acid with NaHCO3 was sufficient to overcome resistance. Conclusions The chemotherapeutic drug etoposide induces the shift toward aerobic glycolysis in the NSCLC rather than SCLC cell lines. The increased lactic acid in extracellular environment plays important role in etoposide resistance through upregulation of MRP expression. These data provide first evidence for the increased lactate production, upon drug treatment, contributes to adaptive resistance in NSCLC and reveal potential vulnerabilities of lactate metabolism and/or pathway suitable for therapeutic targeting. Graphical abstract

Lipoprotein disorder is a common feature of chronic pancreatitis (CP); however, the relationship between lipoprotein disorder and pancreatic fibrotic environment is unclear. Here, we investigated the occurrence and mechanism of pancreatic stellate cell (PSC) activation by lipoprotein metabolites and the subsequent regulation of type 2 immune responses, as well as the driving force of fibrotic aggressiveness in CP. Single-cell RNA sequencing revealed the heterogeneity of PSCs and identified very-low-density lipoprotein receptor (VLDLR)

Parkinson's disease (PD) is a common neurodegenerative disorder without effective disease-modifying therapeutics. Here, we establish a chemogenetic dopamine (DA) neuron ablation model in larval zebrafish with mitochondrial dysfunction and robustness suitable for high-content screening. We use this system to conduct an in vivo DA neuron imaging-based chemical screen and identify the Renin-Angiotensin-Aldosterone System (RAAS) inhibitors as significantly neuroprotective. Knockdown of the angiotensin receptor 1 (Parkinson’s disease is caused by the slow death and deterioration of brain cells, in particular of the neurons that produce a chemical messenger known as dopamine. Certain drugs can mitigate the resulting drop in dopamine levels and help to manage symptoms, but they cause dangerous side-effects. There is no treatment that can slow down or halt the progress of the condition, which affects 0.3% of the population globally. Many factors, both genetic and environmental, contribute to the emergence of Parkinson’s disease. For example, dysfunction of the mitochondria, the internal structures that power up cells, is a known mechanism associated with the death of dopamine-producing neurons. Zebrafish are tiny fish which can be used to study Parkinson’s disease, as they are easy to manipulate in the lab and share many characteristics with humans. In particular, they can be helpful to test the effects of various potential drugs on the condition. Here, Kim et al. established a new zebrafish model in which dopamine-producing brain cells die due to their mitochondria not working properly; they then used this assay to assess the impact of 1,403 different chemicals on the integrity of these cells. A group of molecules called renin-angiotensin-aldosterone (RAAS) inhibitors was shown to protect dopamine-producing neurons and stopped them from dying as often. These are already used to treat high blood pressure as they help to dilate blood vessels. In the brain, however, RAAS worked by restoring certain mitochondrial processes. Kim et al. then investigated whether these results are relevant in other, broader contexts. They were able to show that RAAS inhibitors have the same effect in other animals, and that Parkinson’s disease often progresses more slowly in patients that already take these drugs for high blood pressure. Taken together, these findings therefore suggest that RAAS inhibitors may be useful to treat Parkinson’s disease, as well as other brain illnesses that emerge because of mitochondria not working properly. Clinical studies and new ways to improve these drugs are needed to further investigate and capitalize on these potential benefits.

BACKGROUND Circular RNAs (circRNAs) are key regulators in the progression of various cancers. Abnormal DNA methylation patterns feature prominently in the regulation of the expression of tumor-related genes. This study is aimed at investigating the molecular mechanism of circ_0040809 affecting colorectal cancer (CRC) progression by regulating DNA methyltransferase 1 (DNMT1). METHODS circ_0040809 was selected from the circRNA microarray datasets (GSE142837 and GSE138589). Quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to examine the expression of circ_0040809, miR-515-5p, and DNMT1 mRNA in paired cancerous and paracancerous tissues of 40 CRC patients, as well as in cell lines. Western blotting was conducted for detecting DNMT1 protein expression in CRC cells. Cell proliferation, migration, and apoptosis were assessed through CCK-8, Transwell, and flow cytometry assays. Bioinformatics and dual-luciferase gene assay were conducted to predict and verify, respectively, the targeted relationships between circ_0040809 and miR-515-5p, as well as between miR-515-5p and DNMT1 mRNA. RESULTS In CRC tissues and cells, circ_0040809 and DNMT1 expression are markedly increased, whereas miR-515-5p expression is decreased. Also, high circ_0040809 expression is significantly linked to shorter overall survival. Cell function compensation experiments reveal that circ_0040809 silencing inhibits CRC cell proliferation and migration and promotes apoptosis, while circ_0040809 overexpression has the opposite effects. Mechanistically, circ_0040809 competitively binds to miR-515-5p to elevate DNMT1 expression. Rescue assay reveals that overexpressed miR-515-5p partly counteracts the tumor-facilitating impact of circ_0040809. CONCLUSIONS circ_0040809 facilitates CRC cell proliferation and migration, and inhibits apoptosis, through modulating miR-515-5p/DNMT1 axis. Our study implies that targeting circ_0040809 may be a therapy strategy for CRC treatment.

Odor pollution caused by toxic chemicals with low human olfactory thresholds, such as hydrogen sulfide (H

Background Erythropoiesis and iron homeostasis are closely related; anemia due to lower-risk myelodysplastic syndromes (MDS) remains difficult to treat. In the last decade, we have been committed to improving the regulation of iron metabolism using traditional Chinese medicine (TCM). Previous studies have found that the TCM Yi Gong San (YGS) can reduce the expression of transferrin by inhibiting hepcidin overexpression caused by inflammation, promote the outward transfer of intracellular iron, and improve the symptoms of anemia. Here, our study aimed to compare the efficacy of a conventional drug with YGS with that of conventional medicine with placebo to provide a scientific basis for making clinical decisions. Methods A prospective, multicenter, double-blinded, randomized controlled clinical trial will be conducted to evaluate the therapeutic efficacy of conventional medicine combined with YGS with that of conventional medicine alone in the treatment of MDS. A total of 60 patients would be enrolled in this study, with each treatment group (conventional medicine + YGS and conventional medicine + placebo) comprising 30 patients. Oral medication would be administered twice daily for 3 months. All patients would be followed up throughout the 3-month period. The primary outcome was measured by assessing blood hemoglobin level. The secondary outcome was measured by assessing TCM symptom score, iron metabolism, hepcidin levels, and inflammatory factors. Discussion This trial would aim to demonstrate the effectiveness and feasibility of YGS in the treatment of lower-risk MDS anemia, as well as its impact on inflammatory factors and iron metabolism in patients with lower-risk MDS. Trial registration Chinese Clinical Trials Registry (http://www.chictr.org.cn/) ChiCTR1900026774. Registered on October 21, 2019.

Maintaining the fidelity of nascent peptide chain (NP) synthesis is essential for proteome integrity and cellular health. Ribosome-associated quality control (RQC) serves to resolve stalled translation, during which untemplated Ala/Thr residues are added C terminally to stalled peptide, as shown during C-terminal Ala and Thr addition (CAT-tailing) in yeast. The mechanism and biological effects of CAT-tailing–like activity in metazoans remain unclear. Here we show that CAT–tailing-like modification of poly(GR), a dipeptide repeat derived from amyotrophic lateral sclerosis with frontotemporal dementia (ALS/FTD)-associated GGGGCC (G4C2) repeat expansion in C9ORF72, contributes to disease. We find that poly(GR) can act as a mitochondria-targeting signal, causing some poly(GR) to be cotranslationally imported into mitochondria. However, poly(GR) translation on mitochondrial surface is frequently stalled, triggering RQC and CAT-tailing–like C-terminal extension (CTE). CTE promotes poly(GR) stabilization, aggregation, and toxicity. Our genetic studies in Drosophila uncovered an important role of the mitochondrial protease YME1L in clearing poly(GR), revealing mitochondria as major sites of poly(GR) metabolism. Moreover, the mitochondria-associated noncanonical Notch signaling pathway impinges on the RQC machinery to restrain poly(GR) accumulation, at least in part through the AKT/VCP axis. The conserved actions of YME1L and noncanonical Notch signaling in animal models and patient cells support their fundamental involvement in ALS/FTD.

In the setting of coronary heart diseases (CHDs) on treatment with clopidogrel, ADP-induced platelet aggregation has been demonstrated with ischemic events. However, there were very limited data for predicting ischemic events by platelet function test via dynamic platelet aggregation counting (DPAC). The present study aimed to evaluate the relationship between adenosine diphosphate (ADP)-induced whole blood platelet aggregation rates (PARs) and clinical outcomes in patients with CHDs on treatment with clopidogrel. We have retrospectively analyzed the clinical data of consecutive patients with CHDs based on the electronic medical records between May 2016 and December 2018. The primary endpoint was a composite endpoint events (CEEs) of ischemic cardiovascular events (including acute coronary syndrome, heart failure, transient ischemic attack, and cerebral infarction) and all-cause death. A total of 490 patients (mean age 66.6 years, 71% man) were received ADP-induced PARs via DPAC. On follow-up (mean 374 days), 107 subjects (21.8%) developed CEEs. Cox regression analysis indicated that the risk of CEEs was independently associated with ADP-induced whole blood PARs [HR: 1.023, 95% CI: 1.005-1.041

SUMMARY Amyotrophic lateral sclerosis (ALS) manifests pathological changes in motor neurons and various other cell types. Compared to motor neurons, the contribution of the other cell types to the ALS phenotypes is under-studied. G4C2 repeat expansion in C9ORF72 is the most common genetic cause of ALS along with frontotemporal dementia (C9-ALS/FTD), with increasing evidence supporting repeat-encoded poly(GR) in disease pathogenesis. Here, we show in Drosophila muscle that poly(GR) enters mitochondria and interacts with components of the Mitochondrial Contact Site and Cristae Organizing System (MICOS), altering MICOS dynamics and intra-subunit interactions. This impairs mitochondrial inner membrane structure, ion homeostasis, mitochondrial metabolism, and muscle integrity. Similar mitochondrial defects are observed in patient fibroblasts. Genetic manipulation of MICOS components or pharmacological restoration of ion homeostasis with nigericin effectively rescue the mitochondrial pathology and disease phenotypes in both systems. These results implicate MICOS-regulated ion homeostasis in C9-ALS pathogenesis and suggest potential new therapeutic strategies., Graphical Abstract, In Brief G4C2 repeat expansion in C9ORF72 is the most common genetic cause of ALS. Repeat-encoded poly(GR) is believed to contribute to disease, albeit with not fully defined mechanisms. Li et al. show that poly(GR) targets the MICOS complex, causing mitochondrial toxicity. Manipulating MICOS is beneficial in animal models and patient cells.

The medical imaging literature has witnessed remarkable progress in high-performing segmentation models based on convolutional neural networks. Despite the new performance highs, the recent advanced segmentation models still require large, representative, and high quality annotated datasets. However, rarely do we have a perfect training dataset, particularly in the field of medical imaging, where data and annotations are both expensive to acquire. Recently, a large body of research has studied the problem of medical image segmentation with imperfect datasets, tackling two major dataset limitations: scarce annotations where only limited annotated data is available for training, and weak annotations where the training data has only sparse annotations, noisy annotations, or image-level annotations. In this article, we provide a detailed review of the solutions above, summarizing both the technical novelties and empirical results. We further compare the benefits and requirements of the surveyed methodologies and provide our recommended solutions. We hope this survey article increases the community awareness of the techniques that are available to handle imperfect medical image segmentation datasets., Comment: Accepted for publication in the journal of Medical Image Analysis

Activity of transcriptional co‐activator with PDZ binding domain (TAZ) protein is strongly implicated in the pathogenesis of human cancer and is influenced by tumor metabolism. High levels of lactate concentration in the tumor microenvironment as a result of metabolic reprogramming are inversely correlated with patient overall survival. Herein, we investigated the role of lactate in the regulation of the activity of TAZ and showed that glycolysis‐derived lactate efficiently increased TAZ expression and activity in lung cancer cells. We showed that the reactive oxygen species (ROS) generated by lactate‐fueled oxidative phosphorylation (OXPHOS) in mitochondria activated AKT and thereby inhibited glycogen synthase kinase 3 beta/beta‐transducin repeat‐containing proteins (GSK‐3β/β‐TrCP)‐mediated ubiquitination and degradation of DNA methyltransferase 1 (DNMT1). Upregulation of DNMT1 by lactate caused hypermethylation of TAZ negative regulator of the LATS2 gene promoter, leading to TAZ activation. Moreover, TAZ binds to the promoter of DNMT1 and is necessary for DNMT1 transcription. Our study showed a molecular mechanism of DNMT1 in linking tumor metabolic reprogramming to the Hippo‐TAZ pathway and functional significance of the DNMT1‐TAZ feedback loop in the migratory and invasive potential of lung cancer cells., Glycolysis-derived lactate efficiently increased TAZ expression and activity in lung cancer cells. ROS generated by lactate-fueled OXPHOS in mitochondria activated AKT and thereby inhibited GSK-3β/β-TrCP-mediated ubiquitination and degradation of DNA methyltransferase 1 (DNMT1). Upregulation of DNMT1 caused hypermethylation of the LATS2 gene promoter. TAZ binds to the promoter of DNMT1 and is necessary for DNMT1 transcription.

A facile ratiometric fluorescence method for ascorbic acid (AA) detection was established by combining the fluorescence of MoS

SUMMARYMitochondrial dysfunction and proteostasis failure frequently coexist as hallmarks of neurodegenerative disease. How these pathologies are related is not well understood. Here we describe a phenomenon termed MISTERMINATE (mitochondrial stress-induced translational termination impairment and protein carboxyl terminal extension), which mechanistically links mitochondrial dysfunction with proteostasis failure. We show that mitochondrial dysfunction impairs translational termination of nuclear-encoded mitochondrial mRNAs including complex-I 30kD subunit (C-I30) mRNA, occurring on mitochondrial surface in Drosophila and mammalian cells. Ribosomes stalled at the normal stop codon continue to add to the C-terminus of C-I30 certain amino acids non-coded by mRNA template. C-terminally-extended C-I30 is toxic when assembled into C-I and forms aggregates in the cytosol. Enhancing co-translational quality control prevents C-I30 C-terminal extension and rescues mitochondrial and neuromuscular degeneration in a Parkinson’s disease model. These findings emphasize the importance of efficient translation termination and reveal unexpected link between mitochondrial health and proteome homeostasis mediated by MISTERMINATE.

Epithelial to mesenchymal transition (EMT) is a critical step in the growth and dissemination of malignant diseases, including breast cancer. It is known that microRNAs (miRNAs) play important roles in the regulation of tumor properties in cancers. However, whether miR-497 contributes to EMT in breast cancer cells remains unknown. Our study demonstrated that the expression of miR-497 was significantly decreased in human breast cancer cell lines and breast cancer specimens. In breast cancer cells, EMT was inhibited and promoted by the over-expression as well as depletion of miR-497, respectively. Dual-Luciferase ReporterAassay confirmed that Slug was a direct target of miR-497. The upregulation of miR-497 in breast cancer cells suppressed cell proliferation and induced apoptosis both in vitro and in vivo. Correlation analysis indicated that miR-497 was highly negatively correlated with Slug expression in breast cancer specimens. The knockdown of Slug expression in breast cancer cells significantly suppressed cell proliferation and promoted apoptosis. Our results suggested that the expression of miR-497 is significantly correlated with EMT in breast cancer cells by regulating Slug at the transcriptional as well as translational levels. Therefore, targeting miR-497 may provide a novel strategy for the treatment of breast cancer.

Highly expressed G protein-coupled receptor 81 (GPR81), a receptor for lactate, is emerging as a critical regulator of tumor growth and metastasis. However, the mechanistic basis for its highly expression in cancer cells remains elusive. Here we report that tumor-derived lactate transcriptionally regulates GPR81 expression. We demonstrated that the transcriptional response of GPR81 to lactate is mediated by Signal transducer and activator of transcription 3 (STAT3). Mechanistically, lactate upregulates transcriptional factor Snail and induces the assembly of Snail/EZH2/STAT3 complex. Within this ternary complex, STAT3 activity is strongly enhanced. Consequently, the activated STAT3 by lactate directly binds GPR81promoter and activates its expression. These findings shed light on the transcriptional mechanism by which GPR81 expression is regulated in cancer cells, and provides mechanistic insight into how aberrant signaling and continually high lactate levels due to metabolic switch may yield a feed-forward/self-enabling loop to promote tumor progression.

Metal complexes are widely used as anticancer drugs, while the severe side effects of traditional chemotherapy require new therapeutic modalities. Sonodynamic therapy (SDT) provides a significantly noninvasive ultrasound (US) treatment approach by activating sonosensitizers and initiating reactive oxygen species (ROS) to damage malignant tissues. In this work, three metal 4-methylphenylporphyrin (TTP) complexes (MnTTP, ZnTTP, and TiOTTP) are synthesized and encapsulated with human serum albumin (HSA) to form novel nanosonosensitizers. These nanosonosensitizers generate abundant singlet oxygen (1 O2 ) under US irradiation, and importantly show excellent US-activatable abilities with deep-tissue depths up to 11 cm. Compared to ZnTTP-HSA and TiOTTP-HSA, MnTTP-HSA exhibits the strongest ROS-activatable behavior due to the lowest highest occupied molecular orbital-lowest unoccupied molecular orbital gap energy by density functional theory. It is also effective for deep-tissue photoacoustic/magnetic resonance dual-modal imaging to trace the accumulation of nanoparticles in tumors. Moreover, MnTTP-HSA intriguingly achieves high SDT efficiency for simultaneously suppressing the growth of bilateral tumors away from ultrasound source in mice. This work develops a deep-tissue imaging-guided SDT strategy through well-defined metalloporphyrin nanocomplexes and paves a new way for highly efficient noninvasive SDT treatments of malignant tumors.

Despite progress in the treatment of colorectal cancer, curing metastatic colorectal cancer remains a major unmet medical need worldwide. Here, we describe a T-cell–engaging bispecific antibody (T-BsAb) to redirect polyclonal cytotoxic T cells to eradicate colorectal cancer. A33, a murine antibody specific for GPA33, was humanized to huA33 and reformatted to huA33-BsAb, based on a novel IgG(L)–scFv platform by linking the anti-CD3 huOKT3 scFv to the carboxyl end of the light chain. This T-BsAb was stably expressed in CHO cells and purified as a stable monomer by HPLC, retaining immunoreactivity by FACS through 30 days of incubation at 37°C. In vitro, it induced activation and expansion of unstimulated T cells and elicited potent T-cell–dependent cell-mediated cytotoxicity against colon and gastric cancer cells in an antigen-specific manner. In vivo, huA33-BsAb inhibited the colon and gastric cancer xenografts, in both subcutaneous and intraperitoneal tumor models. More importantly, both microsatellite instable and microsatellite stable colorectal cancer were effectively eliminated by huA33-BsAb. These preclinical results provide further support for the use of IgG(L)–scFv platform to build BsAb, and especially one targeting GPA33 for colorectal cancer. These preclinical results also support further development of huA33-BsAb as a potential immunotherapeutic. Mol Cancer Ther; 17(10); 2164–75. ©2018 AACR.

An ideal cancer therapeutic strategy is expected to possess potent ability to not only ablate primary tumors but also prevent distance metastasis and relapse. In this study, human serum albumin was hybridized with hemoglobin by intermolecular disulfide bonds to develop a hybrid protein oxygen nanocarrier with chlorine e6 encapsulated (C@HPOC) for oxygen self-sufficient photodynamic therapy (PDT). C@HPOC realized the tumor-targeted co-delivery of photosensitizer and oxygen, which remarkably relieved tumor hypoxia. C@HPOC was favorable for more efficient PDT and enhanced infiltration of CD8+ T cells in tumors. Moreover, oxygen-boosted PDT of C@HPOC induced immunogenic cell death, with the release of danger-associated molecular patterns to activate dendritic cells, T lymphocytes, and natural killer cells in vivo. Notably, C@HPOC-mediated immunogenic PDT could destroy primary tumors and effectively suppress distant tumors and lung metastasis in a metastatic triple-negative breast cancer model by evoking syste...

Toward an understanding of the protein interaction network of the human liver An extensive interaction network of human liver-expressed proteins is described, composed of 3484 interactions among 2582 proteins. Proteins associated with liver disease tend to be central and highly connected in the network., Proteome-scale protein interaction maps are available for many organisms, ranging from bacteria, yeast, worms and flies to humans. These maps provide substantial new insights into systems biology, disease research and drug discovery. However, only a small fraction of the total number of human protein–protein interactions has been identified. In this study, we map the interactions of an unbiased selection of 5026 human liver expression proteins by yeast two-hybrid technology and establish a human liver protein interaction network (HLPN) composed of 3484 interactions among 2582 proteins. The data set has a validation rate of over 72% as determined by three independent biochemical or cellular assays. The network includes metabolic enzymes and liver-specific, liver-phenotype and liver-disease proteins that are individually critical for the maintenance of liver functions. The liver enriched proteins had significantly different topological properties and increased our understanding of the functional relationships among proteins in a liver-specific manner. Our data represent the first comprehensive description of a HLPN, which could be a valuable tool for understanding the functioning of the protein interaction network of the human liver.

Background The preferential use of aerobic glycolysis by tumor cells lead to high accumulation of lactate in tumor microenvironment. Clinical evidence has linked elevated lactate concentration with cancer outcomes. However, the role and molecular mechanisms of lactate in cellular senescence and tumor progression remain elusive. Methods The function of Snail in lactate-induced EMT in lung cancer cells was explored by wound healing assay and cell invasion assay. The qRT-PCR and dual luciferase reporter assay were performed to investigate how lactate regulates Snail expression. The level of TGF-β1 in culture supernatant of cells was measured by ELISA for its correlation with extracellular levels of lactate. Ras activity assay and SA-β-gal activity assay were established to determine the effect of lactate on oncogene-induced senescence in human lung epithelial cells. ChIP assays were conducted to determine the binding of snail to p16INK4a promoter. Two TCGA data sets (TCGA-LUAD and TCGA-LUSC) were used to explore the correlations between SNAI1 and CDKN2A expression. Results In this study, we showed the invasive and migratory potential of lung cancer cells was significantly enhanced by lactate and was directly linked to snail activity. We also demonstrated that extracellular acidification itself is a direct cause of the increased snail expression and physiologically coupled to LDHA-dependent conversion of pyruvate to lactate. Mechanistically, lactate exerts its central function in induction of snail and EMT by directly remodeling ECM and releasing activated TGF-β1. We also demonstrated that Snail help premalignant cells to escape the oncogene-induced senescence by directly targeting and inhibiting p16INK4a expression. Conclusions Our study extends the understanding of EMT in tumorigenesis by uncovering the role of snail in cellular senescence. This study also reveals lactate may be a potent tumor-promoting factor and provides the basis for the development of lactate-targeted therapy.

Acute myeloid leukemia (AML), the most common acute leukemia in adults and the second most common cancer in children, is still a lethal disease in the majority of patients, but immunologic approaches have improved outcome. Bispecific antibodies (BsAbs) are novel immunotherapeutics that can redirect immune cells against AML. We now report a tetravalent (2+2) humanized BsAb in the immunoglobulin G light chain single chain fragment variable [IgG(L)-scFv] format to engage polyclonal T cells to kill CD33+ AML targets. In vitro, this BsAb demonstrated strong antigen-specific T-cell-dependent cell-mediated cytotoxicity (TDCC) with an 50% effective concentration (EC50) in the femtomolar range that translated into treatment of established human AML IV xenografts in vivo. Importantly, it could redirect intraperitoneally injected T cells to ablate established and rapidly growing extramedullary subcutaneous AML xenografts in vivo. Furthermore, internalization of CD33 upon BsAb binding was identical to that of a bivalent (1+1) heterodimer, both being substantially less than anti-CD33 IgG. In contrast to the heterodimer, the tetravalent IgG-scFv BsAb was >10-fold more efficient in TDCC of AML cells in vitro and in vivo. This BsAb did not react with and did not kill CD38-CD34+ hematopoietic stem cells from cord blood. We conclude that the novel anti-CD33 IgG(L)-scFv BsAb construct reported here is a potential candidate for clinical development.

Antibodies that bind peptide-MHC (pMHC) complex in a manner akin to T-cell receptor (TCR) have not only helped in understanding the mechanism of TCR-pMHC interactions in the context of T-cell biology, but also spurred considerable interest in recent years as potential cancer therapeutics. Traditional methods to generate such antibodies using hybridoma and B-cell sorting technologies are sometimes inadequate, possibly due to the small contribution of peptide to the overall B-cell epitope space on the surface of the pMHC complex (typical peptide MW = 1 kDa versus MHC MW = 45 kDa), and to the multiple efficiency limiting steps inherent in these methods. In this chapter, we describe a phage display approach for the rapid generation of such antibodies with high specificity and affinity.

Shigella sonnei has become predominant species causing shigellosis in Shanghai. Two hundred ninety-three S. sonnei were isolated in sentinel hospitals of Shanghai in 2011. We found an emergence of 8 strains of S. sonnei with negative phenotype for o-nitrophenyl-β-d-galactopyranoside in late August, which showed distinct pulsed-field gel electrophoresis patterns from the other 285 S. sonnei and had genes deletion in lac and mhp operons.

Harnessing the power of the human immune system to treat cancer is the essence of immunotherapy. Monoclonal antibodies engage the innate immune system to destroy targeted cells. For the last 30 years, antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity have been the main mechanisms of anti-tumor action of unconjugated antibody drugs. Efforts to exploit the potentials of other immune cells, in particular T cells, culminated in the recent approval of two T cell engaging bispecific antibody (T-BsAb) drugs, thereby stimulating new efforts to accelerate similar platforms through preclinical and clinical trials. In this review, we have compiled the worldwide effort in exploring T cell engaging bispecific antibodies. Our special emphasis is on the lessons learned, with the hope to derive insights in this fast evolving field with tremendous clinical potential.

A clustered regularly interspaced short palindromic repeat (CRISPR) typing method has recently been developed and used for typing and subtyping of Salmonella spp., but it is complicated and labor intensive because it has to analyze all spacers in two CRISPR loci. Here, we developed a more convenient and efficient method, namely, CRISPR locus spacer pair typing (CLSPT), which only needs to analyze the two newly incorporated spacers adjoining the leader array in the two CRISPR loci. We analyzed a CRISPR array of 82 strains belonging to 21 Salmonella serovars isolated from humans in different areas of China by using this new method. We also retrieved the newly incorporated spacers in each CRISPR locus of 537 Salmonella isolates which have definite serotypes in the Pasteur Institute's CRISPR Database to evaluate this method. Our findings showed that this new CLSPT method presents a high level of consistency (kappa = 0.9872, Matthew's correlation coefficient = 0.9712) with the results of traditional serotyping, and thus, it can also be used to predict serotypes of Salmonella spp. Moreover, this new method has a considerable discriminatory power (discriminatory index [DI] = 0.8145), comparable to those of multilocus sequence typing (DI = 0.8088) and conventional CRISPR typing (DI = 0.8684). Because CLSPT only costs about $5 to $10 per isolate, it is a much cheaper and more attractive method for subtyping of Salmonella isolates. In conclusion, this new method will provide considerable advantages over other molecular subtyping methods, and it may become a valuable epidemiologic tool for the surveillance of Salmonella infections.

SUMMARY Tau hyperphosphorylation is thought to underlie tauopathy. Working in a Drosophila tauopathy model expressing a human Tau mutant (hTauR406W, or Tau*), we show that zinc contributes to the development of Tau toxicity through two independent actions: by increasing Tau phosphorylation and, more significantly, by directly binding to Tau. Elimination of zinc binding through amino acid substitution of Cys residues has a minimal effect on phosphorylation levels yet essentially eliminates Tau toxicity. The toxicity of the zinc-binding-deficient mutant Tau* (Tau*C2A) and overexpression of native Drosophila Tau, also lacking the corresponding zinc-binding Cys residues, are largely impervious to zinc concentration. Importantly, restoration of zinc-binding ability to Tau* by introduction of a zinc-binding residue (His) into the original Cys positions restores zinc-responsive toxicities in proportion to zinc-binding affinities. These results indicate zinc binding is a substantial contributor to tauopathy and have implications for therapy development.

SummaryIn 2009, an outbreak of aseptic meningitis caused by coxsackievirus B5 (CVB5) occurred in China. Epidemiological investigations of this outbreak revealed that the proportion of severe cases (14/43, 33%) was higher than in other outbreaks associated with CVB5 in China. Phylogenetic analysis of the entire VP1 sequences demonstrated that the CVB5 isolates from the severe cases form a distinct lineage belonging to genogroup E with the Shandong isolates of 2009. A substitution of serine (S) to asparagine (N) at amino acid 95 in the VP1 region may be a major virulence determinant for the virus. Our findings suggest that this new lineage of CVB5 is circulating in China. Further genetic studies are needed in order to gain a better insight into the genetic variability of CVB5 isolates and the relationship with pathogenicity.

We identified 3 atypical Shigella flexneri varieties in China, including 92 strains with multidrug resistance, distinct pulse types, and a novel sequence type. Atypical varieties were prevalent mainly in developed regions, and 1 variant has become the dominant Shigella spp. serotype in China. Improved surveillance will help guide the prevention and control of shigellosis.

Persistent STAT3 activation is a critical event in tumorigenesis and metastatic progression. Recent studies have found higher levels of STAT3 in metastatic tissues than in primary tumor tissues. We speculated that such increased STAT3 activity might be attributed to a loss of function or reduction in expression of metastasis inhibitory protein during cancer progression, and we therefore examined the role of tumor metastasis-suppressor nm23-H1 in the activation of STAT3 in the A549 lung cancer cell line. We found that IL-6-dependent induction of tyrosine phosphorylation and activation of STAT3 were influenced by nm23-H1 inhibition. IL-6-induced STAT3(Tyr705) phosphorylation was significantly enhanced in A549 cells transfected with siRNA specific for nm23-H1, and the effect of nm23-H1 depletion on IL-6-induced STAT3(Tyr705) phosphorylation was reversed by ectopic expression of shRNA-resistant nm23-H1 protein. Moreover, STAT3 directly bound to the STAT3 binding site on the nm23-H1 promoter and activated its expression. Thus, we have identified a new feedback mechanism that might provide insight into an in-built metastasis-suppression function in tumor cells and which could be a logical new target for treatment of early metastatic disease.

Members of transforming growth factor-β(TGF-β) family are the main inducers of epithelial–mesenchymal transition (EMT) during embryogenesis and cancer pathogenesis. However, a significant crosstalk between TGF-β and other signals occurs during the induction of EMT. nm23-H1 was the first metastasis suppressor gene to be identified on the basis of an inverse relationship between nm23-H1 expression and metastasis stage. Despite extensive studies, the mechanism underlying its ability to suppress metastasis is far from elucidated. We demonstrated here that the nm23-H1 negatively regulated TGF-β1-dependent induction of EMT in non-aggressive lung cancer cell line. nm23-H1 knockdown significantly enhanced TGF-β1-induced suppression of epithelial marker E-cadherin and upregulation of mesenchymal markers β-catenin and fibronectin. The invasive and migratory potential of lung cancer cells upon TGF-β1 treatment was also markedly enhanced by nm23-H1 knockdown. On the other hand, the effect of nm23-H1 depletion on TGF-β1-induced EMT was reversed by ectopic re-expression of shRNA-resistant nm23-H1 protein. Furthermore, TGF-β1-induced EMT potentiated by nm23-H1 depletion was partially dependent on transcriptional factor Snail expression. Finally, we found Src kinase is involved in regulation of TGF-β1-induced EMT by nm23-H1. Our results suggest a means of restoring nm23-H1 to suppress TGF-β1-induced EMT that may exploited therapeutically for the management of metastasis diseases.

Eukaryotes employ elaborate mitochondrial quality control (MQC) to maintain the function of the power-generating organelle. Parkinson's disease-associated PINK1 and Parkin actively participate in MQC. However, the signaling events involved are largely unknown. Here we show that mechanistic target of rapamycin 2 (mTORC2) and Tricornered (Trc) kinases act downstream from PINK1 to regulate MQC. Trc is phosphorylated in mTORC2-dependent and mTORC2-independent manners and is specifically localized to mitochondria in response to PINK1, which regulates mTORC2 through mitochondrial complex-I activity. Genetically, mTORC2 and Trc act upstream of Parkin. Thus, multiplex kinase signaling is acting between PINK1 and Parkin to regulate MQC, a process highly conserved in mammals.

To identify a panel of tumor associated autoantibodies which can potentially be used as biomarkers for the early diagnosis of non-small cell lung cancer (NSCLC). Thirty-five unique and in-frame expressed phage proteins were isolated. Based on the gene expression profiling, four proteins were selected for further study. Both receiver operating characteristic curve analysis and leave-one-out method revealed that combined measurements of four antibodies produced have better predictive accuracies than any single marker alone. Leave-one-out validation also showed significant relevance with all stages of NSCLC patients. The panel of autoantibodies has a high potential for detecting early stage NSCLC.

Researches indicate that the dysregulation of microRNA (miRNA) is involved in tumorigenesis. Among such dysregulated miRNAs in cancer, miR-145 is reported to be downregulated in multiple cancers. In this study, we demonstrated the downregulation of miR-145 in triple-negative breast cancer (TNBC) tissues and TNBC cell lines by quantitative reverse-transcription polymerase chain reaction (RT-PCR) analysis. Furthermore, we found that the tumor necrosis factor-alpha (TNF-α)-induced apoptosis was expanded by the transfection of miR-145 in MDA-MB-231 which belongs to the TNBC cell lines. We then indicated that the mechanism by which miR-145 promotes the TNF-α-induced apoptosis is dependent on the formation of RIP1-FADD-caspase-8 complex. The cellular inhibitor of apoptosis (cIAP1), which is the inhibitor of apoptosis protein, was found to be a target of miR-145 in MDA-MB-231 cells. As a result of cIAP1 overexpression, the promotion of miR-145 on TNF-α-induced apoptosis was inhibited in MDA-MB-231 cells. Therefore, our results indicate that miR-145 acts as a tumor suppressor in TNBC, suggesting that the miR-145-cIAP1 axis might be a potential therapeutic target for TNBC.

Translation of mRNAs is tightly regulated and constantly surveyed for errors. Aberrant translation can trigger co-translational protein and RNA quality control processes, impairments of which cause neurodegeneration by still poorly understood mechanism(s). Here we show that quality control of translation of mitochondrial outer membrane (MOM)-localized mRNA intersects with the turnover of damaged mitochondria, both orchestrated by the mitochondrial kinase PINK1. Mitochondrial damage causes stalled translation of complex-I 30 kDa subunit (C-I30) mRNA on MOM, triggering the recruitment of co-translational quality control factors Pelo, ABCE1, and NOT4 to the ribosome/mRNA-ribonucleoprotein complex. Damage-induced ubiquitination of ABCE1 by NOT4 generates poly-ubiquitin signals that attract autophagy receptors to MOM to initiate mitophagy. In the Drosophila PINK1 model, these factors act synergistically to restore mitophagy and neuromuscular tissue integrity. Thus ribosome-associated co-translational quality control generates an early signal to trigger mitophagy. Our results have broad therapeutic implications for the understanding and treatment of neurodegenerative diseases.

HDM2 is a p53-specific E3 ubiquitin ligase. Its overexpression leads to excessive inactivation of tumor protein p53, diminishing its tumor suppressor function. HDM2 also affects the cell cycle, apoptosis and tumorigenesis through interacting with other molecules, including several ribosomal proteins. To identify novel HDM2 regulators, we performed a yeast two-hybrid screening using HDM2 as bait. Among the candidates, ribosomal protein L26 (RPL26) was characterized as a novel HDM2-interactor. The interaction between HDM2 and RPL26 was further validated by in vivo and in vitro assays. RPL26 modulates the HDM2–p53 interaction by forming a ternary complex among RPL26, HDM2 and p53, which stabilize p53 through inhibiting the ubiquitin ligase activity of HDM2. The ribosomal stress caused by a low dose of Act D enhances RPL26–HDM2 interaction and activates p53. Overexpression of RPL26 results in activating of p53, inhibits cell proliferation and induces a p53-dependent cell cycle arrest. These results provide a novel regulatory mechanism of RPL26 to activate p53 by inhibiting HDM2.

PurposeThis study aims to explore the association of CpG island methylator phenotype (CIMP) involving tumor suppressor genes on short arm of chromosome 3 (3p) with increased risk of non-small cell lung cancer (NSCLC).Methods and MaterialsIn this study, four NSCLC cell lines were cultured, and peripheral blood mononuclear cell (PBMC) specimens from 80 patients with NSCLC and 80 matched controls were collected for 3p-involved CIMP (3pCIMP) analysis. 3pCIMP was referred to as having at least three synchronously methylated genes of 3p per sample. Methylation-specific polymerase chain reaction was performed to examine the methylation status of each gene. DNA demethylation of NSCLC cell lines was achieved through the treatment with 5-aza-deoxycytidine. Logistic regression was used to assess odds ratios and 95% confidence intervals, which were adjusted for gender, age, and smoking status.ResultsDemethylation experiment showed that 3pCIMP status could play an important role in NSCLC cell proliferation. A total of 97.5% of PBMC specimens from NSCLC patients presented promoter methylation of any one of six genes (hOGG1, RAR-B, SEMA3B, RASSF1A, BLU, or FHIT) on 3p. Interestingly, 3pCIMP+ was found in 43.8% of NSCLC PBMC specimens and only in 6.3% of normal PBMC samples. The data suggest that 3pCIMP status is significantly associated with NSCLC and normal PBMC samples (p < 0.001). More importantly, the results show that 3pCIMP positive carriers have a 12.8-fold increased risk of NSCLC (adjusted odds ratio, 12.8; 95% confidence interval, 4.38–37.4, p < 0.001) in Chinese population.ConclusionsThis is the first evidence of an association between PBMC 3pCIMP and risk for NSCLC.

Age-related macular degeneration (AMD), the leading cause of severe vision loss in the elderly, is a complex disease that results from genetic modifications that increase susceptibility to environmental exposures. Smoking, a major source of oxidative stress, increases the incidence and severity of AMD, and antioxidants slow progression, suggesting that oxidative stress plays a major role. Polymorphisms in the complement factor H (CFH) gene that reduce activity of CFH increase the risk of AMD. In this study we demonstrate an interaction between these two risk factors, because oxidative stress reduces the ability of an inflammatory cytokine, interferon-gamma, to increase CFH expression in retinal pigmented epithelial cells. The interferon-gamma-induced increase in CFH is mediated by transcriptional activation by STAT1, and its suppression by oxidative stress is mediated by acetylation of FOXO3, which enhances FOXO3 binding to the CFH promoter, reduces its binding to STAT1, inhibits STAT1 interaction with the CFH promoter, and reduces expression of CFH. Expression of SIRT1, a mammalian homolog of NAD-dependent protein deacetylase sir2, attenuated FOXO3 recruitment to the CFH regulatory region and reversed the H(2)O(2)-induced repression of CFH gene expression. These data suggest an important interaction between environmental exposure and genetic susceptibility in the pathogenesis of AMD and, by elucidating molecular signaling involved in the interaction, provide potential targets for therapeutic intervention.

Angiogenesis is a key factor in the growth and dissemination of malignant diseases, including breast cancer, with significant implications for its clinical management. It is known that microRNAs (miRNAs) play important roles in regulating tumor properties in cancers. However, whether miR-497 contributes to breast cancer angiogenesis remains unknown. Our study demonstrated that miR-497 was significantly downregulated in breast cancer tissue samples and cell lines. Conditioned medium obtained from breast cancer cell line MCF-7, treated with miR-497 mimics, suppressed the proliferation and tube formation of human umbilical vein endothelial cells in vitro, in comparison with the untransfected cells or cells transfected with the control vector alone. Furthermore, western blot assay confirmed that the overexpression of miR-497 reduced VEGF and HIF-1α protein levels. In addition, stable transfection of miR-497 inhibited tumorigenicity and angiogenesis in vivo. Moreover, HIF-1α was also increased in the breast cancer cells under a hypoxic condition, while the ectopic expression of miR-497 partially restored its level. Taken together, our findings indicate that miR-497 is a potential target for the biological therapy of breast cancer. Moreover, miR-497 inhibited the growth of tumors and reduced angiogenesis in a nude mouse xenograft tumor model, which was probably caused by the downregulation of pro-angiogenic molecules, such as VEGF and HIF-1α.

From December 2012 to February 2013, two outbreaks of acute respiratory disease caused by HAdV-7 were reported in China. We investigated possible transmission links between these two seemingly unrelated outbreaks by integration of epidemiological and whole-genome sequencing (WGS) data. WGS analyses showed that the HAdV-7 isolates from the two outbreaks were genetically indistinguishable; however, a 12 bp deletion in the virus-associated RNA gene distinguished the outbreak isolates from other HAdV-7 isolates. Outbreak HAdV-7 isolates demonstrated increased viral replication compared to non-outbreak associated HAdV-7 isolate. Epidemiological data supported that the first outbreak was caused by introduction of the novel HAdV-7 virus by an infected recruit upon arrival at the training base. Nosocomial transmission by close contacts was the most likely source leading to onset of the second HAdV-7 outbreak, establishing the apparent transmission link between the outbreaks. Our findings imply that in-hospital contact investigations should be encouraged to reduce or interrupt further spread of infectious agents when treating outbreak cases and WGS can provide useful information guiding infection-control interventions.

The CpG island aberrant promoter methylation in the tumor suppressor gene region plays an important role in the process of tumorigenesis. Relevant evidence shows that the promoter methylation of RAS association domain family 1A (RASSF1A) gene, a tumor suppressor gene, has a close relationship with non-small cell lung cancer (NSCLC) development; therefore, RASSF1A may be a potential NSCLC biomarker. This paper discussed and summarized the relationship between RASSF1A gene promoter methylation frequency and NSCLC through meta-analysis.By searching Medline, EMBASE, CNKI, and Wanfang database, we selected and collected the published articles regarding RASSF1A gene promoter methylation and NSCLC risk according to the marked inclusion and exclusion criteria. Through meta-analysis, combined odds ratio (OR) and 95% confidence interval (CI) data were used to analyze the RASSF1A gene promoter methylation and NSCLC relationship.A total of 23 articles were utilized in this study. Results indicated that the RASSF1A gene promoter methylation rate was 41.50% (95%CI: 34%-49%) in NSCLC tissue and was 5.58% (95%CI: 2%-9%) for the control group. Compared with normal lung tissue, RASSF1A methylation frequency in tumor tissue was significantly higher than that of the control group (OR=8.72, 95%CI: 4.88-15.58, P0.05). Subgroup analysis showed that the RASSF1A gene promoter methylation rate of tumor tissue was higher than that of plasma group (OR=10.99, 95%CI: 2.48-48.68) and normal control tissue group (OR=8.74, 95%CI: 4.39-17.41).The rate of RASSF1A promoter gene methylation in NSCLC patient tissue samples was higher than that of normal lung samples, whereas the rate of RASSF1A promoter gene methylation in the tissue has more significant effect on lung cancer occurrence. This finding indicates that RASSF1A gene promoter methylation could be used as an NSCLC biomarker and was involved in NSCLC carcinogenic effects.背景与目的 肿瘤发生、发展过程中，抑癌基因启动子区域CpG岛异常甲基化起着重要的作用。已有研究显示RAS相关区域家族1A（Ras association domain family 1A, RASSF1A）基因，作为一个抑癌基因其启动子区域甲基化与非小细胞肺癌（non-small cell lung cancer, NSCLC）的发生发展密切相关。在NSCLC患者癌组织中RASSF1A基因启动子往往表现为异常高甲基化。本研究采用meta分析的方法探讨RASSF1A基因启动子甲基化与NSCLC发生之间的关系。方法 通过检索Medline、EMBASE、CNKI和万方数据库，按照已拟定的纳入与剔除标准筛选收集公开发表的关于RASSF1A基因启动子甲基化与NSCLC相关性的研究。以比值比（odds ratio, OR）和95%置信区间（confidence interval, CI）为效应指标，分析RASSF1A基因启动子甲基化与NSCLC的关系。结果 共有23篇文献纳入本研究，RASSF1A基因启动子甲基化率在NSCLC患者肺部组织和对照组中分别为41.50%（95%CI: 34%-49%）和5.58%（95%CI: 2%-9%），meta分析显示肿瘤组织中的甲基化率高于对照组（OR=8.72, 95%CI:4.88-15.58, P0.05）；亚组分析显示:肿瘤组织中的甲基化频率高于血浆（OR=10.99, 95%CI:2.48-48.68）和正常对照组织（OR=8.74, 95%CI: 4.39-17.41）。结论 NSCLC患者肺癌组织中RASSF1A基因启动子甲基化率高于对照组，组织中RASSF1A基因启动子甲基化率对肺癌的发生更具影响，RASSSF1A甲基化可能与肺癌的发生存在相关并可作为肺癌诊断的潜在标志物。.背景与目的 肿瘤发生、发展过程中，抑癌基因启动子区域CpG岛异常甲基化起着重要的作用。已有研究显示RAS相关区域家族1A（Ras association domain family 1A, RASSF1A）基因，作为一个抑癌基因其启动子区域甲基化与非小细胞肺癌（non-small cell lung cancer, NSCLC）的发生发展密切相关。在NSCLC患者癌组织中RASSF1A基因启动子往往表现为异常高甲基化。本研究采用meta分析的方法探讨RASSF1A基因启动子甲基化与NSCLC发生之间的关系。方法 通过检索Medline、EMBASE、CNKI和万方数据库，按照已拟定的纳入与剔除标准筛选收集公开发表的关于RASSF1A基因启动子甲基化与NSCLC相关性的研究。以比值比（odds ratio, OR）和95%置信区间（confidence interval, CI）为效应指标，分析RASSF1A基因启动子甲基化与NSCLC的关系。结果 共有23篇文献纳入本研究，RASSF1A基因启动子甲基化率在NSCLC患者肺部组织和对照组中分别为41.50%（95%CI: 34%-49%）和5.58%（95%CI: 2%-9%），meta分析显示肿瘤组织中的甲基化率高于对照组（OR=8.72, 95%CI:4.88-15.58, P0.05）；亚组分析显示:肿瘤组织中的甲基化频率高于血浆（OR=10.99, 95%CI:2.48-48.68）和正常对照组织（OR=8.74, 95%CI: 4.39-17.41）。结论 NSCLC患者肺癌组织中RASSF1A基因启动子甲基化率高于对照组，组织中RASSF1A基因启动子甲基化率对肺癌的发生更具影响，RASSSF1A甲基化可能与肺癌的发生存在相关并可作为肺癌诊断的潜在标志物。.

Shigella flexneri is an important etiological agent of bacillary dysentery in developing countries. The Hfq protein is thought to play a major regulatory role in various cellular processes in this organism. However, the roles of Hfq in stress tolerance and virulence in S. flexneri in response to environmental stress have not been fully studied. In this study, hfq was highly expressed when S. flexneri was exposed to low pH. Growth retardation was observed in the hfq deletion mutant at pH values ranging from 5.0 to 7.0 and the survival rate of the mutant strain was reduced by 60% in acidic conditions (pH 3.0) compared with the wild-type strain. Additionally, competitive invasion assays in HeLa cells and lung invasion assays showed that the virulence of the hfq deletion mutant was significantly decreased. An evaluation of the mechanism revealed that, along with the expression of the Type III secretion system genes, acid resistance genes were also increased with acid stress. Interestingly, a statistically strong linear correlation was observed between the expression of hfq and Type III secretion system genes, as well as between hfq and acid resistance genes, under various pH conditions. In this study, we provide evidence that Hfq regulates genes related to acid resistance for survival under acid stress and controls virulence through the positive regulation of Type III secretion systems. Importantly, we propose that hfq is a key factor in maximal adaptation to host acid stress during infection, regulating acid stress tolerance and virulence in response to acid stress in S. flexneri.

A 23-year-old male died of severe pneumonia and respiratory failure in a tertiary hospital in Beijing, and 4 out of 55 close contacts developed fever. Molecular analysis confirmed human adenovirus type 7 (HAdV7) as the causative agent. We highlight the importance of early diagnosis and treatment and proper transmission control of HAdV7.

Shigella flexneri serotype 1b is among the most prominent serotypes in developing countries, followed by serotype 2a. However, only limited data is available on the global phenotypic and genotypic characteristics of S. flexneri 1b. In the present study, 40 S. flexneri 1b isolates from different regions of China were confirmed by serotyping and biochemical characterization. Antimicrobial susceptibility testing showed that 85% of these isolates were multidrug-resistant strains and antibiotic susceptibility profiles varied between geographical locations. Strains from Yunnan were far more resistant than those from Xinjiang, while only one strain from Shanghai was resistant to ceftazidime and aztreonam. Fifteen cephalosporin resistant isolates were identified in this study. ESBL genes (bla SHV, bla TEM, bla OXA, and bla CTX-M) and ampC genes (bla MOX, bla FOX, bla MIR(ACT-1), bla DHA, bla CIT and bla ACC) were subsequently detected among the 15 isolates. The results showed that these strains were positive only for bla TEM, bla OXA, bla CTX-M, intI1, and intI2. Furthermore, pulsed-field gel electrophoresis (PFGE) analysis showed that the 40 isolates formed different profiles, and the PFGE patterns of Xinjiang isolates were distinct from Yunnan and Shanghai isolates by one obvious, large, missing band. In summary, similarities in resistance patterns were observed in strains with the same PFGE pattern. Overall, the results supported the need for more prudent selection and use of antibiotics in China. We suggest that antibiotic susceptibility testing should be performed at the start of an outbreak, and antibiotic use should be restricted to severe Shigella cases, based on resistance pattern variations observed in different regions. The data obtained in the current study might help to develop a strategy for the treatment of infections caused by S. flexneri 1b in China.

SummaryMitochondria play essential roles in many aspects of biology, and their dysfunction has been linked to diverse diseases. Central to mitochondrial function is oxidative phosphorylation (OXPHOS), accomplished by respiratory chain complexes (RCCs) encoded by nuclear and mitochondrial genomes. How RCC biogenesis is regulated in metazoans is poorly understood. Here we show that Parkinson’s disease (PD)-associated genes PINK1 and Parkin direct localized translation of certain nuclear-encoded RCC (nRCC) mRNAs. Translationally repressed nRCC mRNAs are localized in a PINK1/Tom20-dependent manner to mitochondrial outer membrane, where they are derepressed and activated by PINK1/Parkin through displacement of translation repressors, including Pumilio and Glorund/hnRNP-F, a Parkin substrate, and enhanced binding of activators such as eIF4G. Inhibiting the translation repressors rescued nRCC mRNA translation and neuromuscular-degeneration phenotypes of PINK1 mutant, whereas inhibiting eIF4G had opposite effects. Our results reveal previously unknown functions of PINK1/Parkin in RNA metabolism and suggest new approaches to mitochondrial restoration and disease intervention.

The largest isoform of the Shc adapter protein, p66Shc, has been implicated in oxidative damage-induced apoptosis in vital organs, because mice deficient in p66Shc have a 30% increase in life span and are resistant to the lethal effects of systemically administered paraquat, a source of severe oxidative damage. In this study, we utilized siRNA directed against the CH2 domain of Shc, to reduce p66Shc, but not p52Shc nor p46Shc in retinal pigmented epithelial (RPE) cells. RPE cells deficient in p66Shc had reduced susceptibility to oxidative stress-induced apoptosis. Compared to control cells, those with reduced p66Shc had increased basal and oxidative stress-induced NF-κB transcriptional activity, increased levels of antioxidant enzymes, and less generation of reactive oxygen species when challenged with H2O2. The increase in oxidative stress-induced NF-κB activity was mediated by activation of ERK. Compared to eyes injected with GFP siRNA, those injected with p66Shc siRNA showed less loss of retinal function as assessed by electroretinograms from paraquat-induced oxidative stress. These data suggest that p66Shc and molecular signals involved in its regulation provide therapeutic targets for retinal degenerations in which oxidative-damage plays a major role, including age-related macular degeneration and cone cell death in retinitis pigmentosa. J. Cell. Physiol. 209: 996–1005, 2006. © 2006 Wiley-Liss, Inc.