Search

Background: Chronic obstructive pulmonary disease (COPD) contributes to the incidence and prognosis of lung cancer. The presence of COPD significantly increases the risk of lung squamous cell carcinoma (LSCC). COPD may promote an immunosuppressive microenvironment in LSCC by regulating the expression of immune‐inhibitory factors in T cells, although the mechanisms remain unclear. In this study, we aimed to decipher the tumour microenvironment signature for LSCC with COPD at a single‐cell level. Methods: We performed single‐cell RNA sequencing on tumour tissues from LSCC with or without COPD, then investigated the features of the immune and tumour cells. We employed multiple techniques, including multispectral imaging, flow cytometry, tissue microarray analysis, survival analysis, co‐culture systems and in vitro and in vivo treatment experiments, to validate the findings obtained from single‐cell analyses. Results: LSCC with COPD showed increased proportions of tumour‐associated macrophages (TAMs) and higher levels of CD8+ T cell exhaustion molecules, which contributed to an immunosuppressive microenvironment. Further analysis revealed a critical cluster of CD74+ tumour cells that expressed both epithelial and immune cell signatures, exhibited a stronger capacity for tumorigenesis and predicted worse overall survival. Notably, migration inhibitory factor (MIF) secreted by TAMs from LSCC with COPD may promote the activation of CD74. MIF‐CD74 may interact with CD8+ T cells and impair their anti‐tumour activity by regulating the PI3K‐STAT3‐programmed cell death‐1 ligand 1 signalling pathway, facilitating tumour proliferation and immune evasion. Conclusions: Our comprehensive picture of the tumour ecosystem in LSCC with COPD provides deeper insights into relevant immune evasion mechanisms and potential targets for immunotherapy. Highlight: Our results demonstrated higher proportions of tumour‐associated macrophages (TAMs) and higher levels of exhaustion molecules in CD8+ T cells in the microenvironment of LSCC with COPD.CD74+tumour cells were associated with poor disease prognosis.Migration inhibitory factor (MIF)‐CD74 may interact with CD8+ T cells and impair their anti‐tumour activity by regulating the PI3K‐STAT3‐PD‐L1 signalling pathway, facilitating immune evasion. [ABSTRACT FROM AUTHOR]

Background: Detection of lung cancer at earlier stage can greatly improve patient survival. We aim to develop, validate, and implement a cost-effective ctDNA-methylation-based plasma test to aid lung cancer early detection. Methods: Case-control studies were designed to select the most relevant markers to lung cancer. Patients with lung cancer or benign lung disease and healthy individuals were recruited from different clinical centers. A multi-locus qPCR assay, LunaCAM, was developed for lung cancer alertness by ctDNA methylation. Two LunaCAM models were built for screening (-S) or diagnostic aid (-D) to favor sensitivity or specificity, respectively. The performance of the models was validated for different intended uses in clinics. Results: Profiling DNA methylation on 429 plasma samples including 209 lung cancer, 123 benign diseases and 97 healthy participants identified the top markers that detected lung cancer from benign diseases and healthy with an AUC of 0.85 and 0.95, respectively. The most effective methylation markers were verified individually in 40 tissues and 169 plasma samples to develop LunaCAM assay. Two models corresponding to different intended uses were trained with 513 plasma samples, and validated with an independent collection of 172 plasma samples. In validation, LunaCAM-S model achieved an AUC of 0.90 (95% CI: 0.88–0.94) between lung cancer and healthy individuals, whereas LunaCAM-D model stratified lung cancer from benign pulmonary diseases with an AUC of 0.81 (95% CI: 0.78–0.86). When implemented sequentially in the validation set, LunaCAM-S enables to identify 58 patients of lung cancer (90.6% sensitivity), followed by LunaCAM-D to remove 20 patients with no evidence of cancer (83.3% specificity). LunaCAM-D significantly outperformed the blood test of carcinoembryonic antigen (CEA), and the combined model can further improve the predictive power for lung cancer to an overall AUC of 0.86. Conclusions: We developed two different models by ctDNA methylation assay to sensitively detect early-stage lung cancer or specifically classify lung benign diseases. Implemented at different clinical settings, LunaCAM models has a potential to provide a facile and inexpensive avenue for early screening and diagnostic aids for lung cancer. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate oropharyngeal microbiota alterations during the progression of coronavirus disease 2019 (COVID-19) by analyzing these alterations during the infection and clearance processes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The diagnosis of COVID-19 was confirmed by using positive SARS-CoV-2 quantitative reverse transcription polymerase chain reaction (RT-qPCR). The alterations in abundance, diversity, and potential function of the oropharyngeal microbiome were identified using metatranscriptomic sequencing analyses of oropharyngeal swab specimens from 47 patients with COVID-19 (within a week after diagnosis and within two months after recovery from COVID-19) and 40 healthy individuals. As a result, in the infection process of SARS-CoV-2, compared to the healthy individuals, the relative abundances of Prevotella, Aspergillus, and Epstein–Barr virus were elevated; the alpha diversity was decreased; the beta diversity was disordered; the relative abundance of Gram-negative bacteria was increased; and the relative abundance of Gram-positive bacteria was decreased. After the clearance of SARS-CoV-2, compared to the healthy individuals and patients with COVID-19, the above disordered alterations persisted in the patients who had recovered from COVID-19 and did not return to the normal level observed in the healthy individuals. Additionally, the expressions of several antibiotic resistance genes (especially multi-drug resistance, glycopeptide, and tetracycline) in the patients with COVID-19 were higher than those in the healthy individuals. After SARS-CoV-2 was cleared, the expressions of these genes in the patients who had recovered from COVID-19 were lower than those in the patients with COVID-19, and they were different from those in the healthy individuals. In conclusion, our findings provide evidence that potential secondary infections with oropharyngeal bacteria, fungi, and viruses in patients who have recovered from COVID-19 should not be ignored; this evidence also highlights the clinical significance of the oropharyngeal microbiome in the early prevention of potential secondary infections of COVID-19 and suggests that it is imperative to choose appropriate antibiotics for subsequent bacterial secondary infection in patients with COVID-19. [ABSTRACT FROM AUTHOR]

Background. Various studies have produced contradictory results on the prognostic role of the CpG island methylator phenotype (CIMP) among colorectal cancer (CRC) patients. Although a meta-analysis published in 2014 reported a worse prognosis of CIMP among CIMP-high (CIMP-H) CRC patients, the sample sizes of the major included studies were small. In this study, we included the most recent studies with large sample sizes and performed an updated meta-analysis on the relationship between CIMP and CRC prognosis. Methods. A search of MEDLINE, Web of Science, and Cochrane for studies related to CIMP and CRC published until July 2021 was conducted based on the PICO (participant, intervention, control, outcome) framework. Data extraction and literature analyses were performed according to PRISMA standards. Results. In the present update, 36 eligible studies (20 recently published) reported survival data in 15315 CRC patients, 18.3% of whom were characterized as CIMP-H. Pooled analysis suggested that CIMP-H was associated with poorer overall survival (OS) (hazard ratio HR = 1.37 , 95% CI: 1.26–1.48) and disease-free survival/progression-free survival/recurrence-free survival (DFS/PFS/RFS) (HR = 1.51 , 95% CI: 1.19–1.91) among CRC patients. Subgroup analysis based on tumor stage and DNA mismatch repair (MMR) status showed that only patients with stages III-IV and proficient MMR (pMMR) tumors showed a significant association between CIMP-H and shorter OS, with HRs of 1.52 and 1.37, respectively. Three studies were pooled to explore the predictive value of CIMP on CRC patient DFS after receiving postoperative chemotherapy, and no significant correlation was found. Conclusion. CIMP-H is associated with a significantly poor prognosis in CRC patients, especially those with stage III-IV and pMMR tumors. However, the predictive value of CIMP needs to be confirmed by more prospective randomized studies. [ABSTRACT FROM AUTHOR]

A previously unknown beta coronavirus, SARS‐CoV‐2, was discovered from a cluster of patients with pneumonia of unknown cause in Wuhan since the end of 2019. Ever since the start of COVID‐19, government administrations, academic institutions, and technology enterprises are under unprecedented cooperation in controlling this outbreak from pathogen identification, epidemic situation assessment, to outbreak containment. Timely identification, isolation, and whole‐genome sequencing of SARS‐CoV‐2 have laid the foundation for effective control of this novel infection. With the increasing case numbers worldwide, more real‐time information is emerging, changing our understandings to SARS‐CoV‐2 outbreak, and nonetheless refining the outbreak control responses. The efficient management of COVID‐19 requires global collaboration and an efficient share of information. [ABSTRACT FROM AUTHOR]

DNA mismatch repair (MMR) status was considered to be a potential prognostic factor for colorectal cancer (CRC) but with conflicting reports, and varied in terms of TNM stages. Its relationship with prognosis in stage II‐III CRC had not yet been systematically established. Therefore, we retrieved eligible studies published through May 2019, and screened out 51 studies that reported survival data (overall survival [OS] and/or disease‐free survival [DFS]) in 28 331 CRC patients at stage II‐III, totally 16.4% of whom were characterized as deficient MMR (dMMR). Significant associations of dMMR status were observed with longer OS (Hazard Ratio [HR] = 0.74, 95% CI: 0.68‐0.82; P <.001), as well as DFS (HR = 0.67, 95% CI: 0.59‐0.75, P <.001). However, dMMR patients received no statistically significant benefit from fluoropyrimidine‐based treatment for either OS (HR = 0.84, 95%CI: 0.60‐1.17; P =.31) or DFS (HR = 0.83, 95%CI: 0.60‐1.15; P =.27), compared with that in proficient MMR (pMMR) patients for both OS (HR = 0.55, 95% CI: 0.43‐0.71; P <.001) and DFS (HR = 0.60, 95% CI: 0.50‐0.73; P <.001). Our analysis indicate that dMMR CRC patients at stage II‐III had higher OS and DFS than pMMR ones, and fluoropyrimidine‐based chemotherapy could improve survival in pMMR patients rather than dMMR ones. [ABSTRACT FROM AUTHOR]

Previous studies indicate that ion channels are mediators of bioelectricity promoting wound closure/regeneration in nonmammalian, lower vertebrate systems. The role of ion channels however in regeneration of wounds in mammalian systems that do not regenerate as adults is not yet defined. Using a mammalian model system that allows us to determine differentially expressed genes when skin regenerates and when skin does not regenerate after wound induction, we identified two potassium channels, kcnh2 and kcnj8, to be (1) differentially expressed between the two states and (2) highly expressed after wound induction at the nonregenerative state. We also found that kcnh2 small molecule inhibitor enhanced wound healing while kcnj8 small molecule inhibitor did not. In contrast, kcnj8 activator accelerated wound healing and even augmented the effect of kcnh2 inhibition. These results provide evidence for the first time that potassium channels may mediate skin wound healing and regeneration interactively. [ABSTRACT FROM AUTHOR]

BRAFV600E/K is a frequent mutationally active tumor-specific kinase in melanomas that is currently targeted for therapy by the specific inhibitor PLX4032. Our studies with melanoma tumor cells that are BRAFV600E/K and BRAFWT showed that, paradoxically, while PLX4032 inhibited ERK1/2 in the highly sensitive BRAFV600E/K, it activated the pathway in the resistant BRAFWT cells, via RAF1 activation, regardless of the status of mutations in NRAS or PTEN. The persistently active ERK1/2 triggered downstream effectors in BRAFWT melanoma cells and induced changes in the expression of a wide-spectrum of genes associated with cell cycle control. Furthermore, PLX4032 increased the rate of proliferation of growth factor-dependent NRAS Q61L mutant primary melanoma cells, reduced cell adherence and increased mobility of cells from advanced lesions. The results suggest that the drug can confer an advantage to BRAFWT primary and metastatic tumor cells in vivo and provide markers for monitoring clinical responses. [ABSTRACT FROM AUTHOR]

Abstract: A key step in cancer development is clonal expansion. The increased number of mutant cells allows a clinical phenotype and increases the probability that one of the cells will be mutated in an additional gene. For skin cancer, observations on p53-mutant keratinocyte clones in epidermal sheets of UVB-irradiated mice reveal that mutant stem cells are normally restrained within their stem cell compartment. Chronic UVB exposure drives clonal expansion by a non-mutational mechanism, and this mechanism allows mutant stem cells to escape from their own stem cell compartment and colonize adjacent compartments. In the absence of escape, cells proliferate without occupying additional territory. The non-mutational clonal expansion mechanism appears to be UVB-induced apoptosis, which deletes DNA-damaged cells in unmutated stem cell compartments but will preferentially spare death-resistant p53-mutant cells. An additional source of apoptotic selection pressure may come from UV-irradiated melanin. [Copyright &y& Elsevier]

The E2f1 transcription factor, which regulates genes required for S-phase entry[SUP1-4], also induces apoptosis by transcriptional and post-translational mechanisms[SUP5-8]. As E2f1 is inducible by DNA damage[SUP9,10] we investigated its importancein vivo in ultraviolet (UV)-induced apoptosis, a protective mechanism that prevents the epidermis from accumulating UV-induced mutations[SUP11,12]. Contrary to expectation,E2f1[SUP-/-] mice demonstrated enhanced keratinocyte apoptosis after UVB exposure, whereas apoptosis was suppressed by epidermis-specific overexpression of human E2F1. Apoptosis induced by γ-radiation was also repressed by E2f1.E2f1[SUP-/-];Trp53[SUP-/-]double knockout mice exhibited the elevated UVB-induced apoptosis ofE2f1[SUP-/-] alone, rather than the profound apoptosis defect seen inTrp53[SUP-/-] mice, indicating that Trp53 (p53) lies functionally upstream of E2f1. Transfecting E2F1 intoE2f1[SUP-/-];Trp53[SUP-/-] primary fibroblasts suppressed UVB-induced apoptosis and this suppression was relieved byTrp53. The double knockout also reverted the abnormal sex ratio and early-onset tumours ofTrp53[SUP-/-] mice. These results imply that E2f1 functions as a suppressor of an apoptosis pathway that is initiated by DNA photoproducts and perhaps genetic abnormalities; p53 relieves this suppression. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate oropharyngeal microbiota alterations during the progression of coronavirus disease 2019 (COVID-19) by analyzing these alterations during the infection and clearance processes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The diagnosis of COVID-19 was confirmed by using positive SARS-CoV-2 quantitative reverse transcription polymerase chain reaction (RT-qPCR). The alterations in abundance, diversity, and potential function of the oropharyngeal microbiome were identified using metatranscriptomic sequencing analyses of oropharyngeal swab specimens from 47 patients with COVID-19 (within a week after diagnosis and within two months after recovery from COVID-19) and 40 healthy individuals. As a result, in the infection process of SARS-CoV-2, compared to the healthy individuals, the relative abundances of Prevotella , Aspergillus , and Epstein-Barr virus were elevated; the alpha diversity was decreased; the beta diversity was disordered; the relative abundance of Gram-negative bacteria was increased; and the relative abundance of Gram-positive bacteria was decreased. After the clearance of SARS-CoV-2, compared to the healthy individuals and patients with COVID-19, the above disordered alterations persisted in the patients who had recovered from COVID-19 and did not return to the normal level observed in the healthy individuals. Additionally, the expressions of several antibiotic resistance genes (especially multi-drug resistance, glycopeptide, and tetracycline) in the patients with COVID-19 were higher than those in the healthy individuals. After SARS-CoV-2 was cleared, the expressions of these genes in the patients who had recovered from COVID-19 were lower than those in the patients with COVID-19, and they were different from those in the healthy individuals. In conclusion, our findings provide evidence that potential secondary infections with oropharyngeal bacteria, fungi, and viruses in patients who have recovered from COVID-19 should not be ignored; this evidence also highlights the clinical significance of the oropharyngeal microbiome in the early prevention of potential secondary infections of COVID-19 and suggests that it is imperative to choose appropriate antibiotics for subsequent bacterial secondary infection in patients with COVID-19.

Understanding immune cell phenotypes in the tumor microenvironment (TME) is essential for explaining and predicting progression of non-small cell lung cancer (NSCLC) and its response to immunotherapy. Here we describe the single-cell transcriptomics of CD45 + immune cells from tumors, normal tissues and blood of NSCLC patients. We identified three clusters of immune cells exerting immunosuppressive effects: CD8 + T cells with exhausted phenotype, tumor-associated macrophages (TAMs) with a pro-inflammatory M2 phenotype, and regulatory B cells (B regs) with tumor-promoting characteristics. We identified genes that may be mediating T cell phenotypes, including the transcription factors ONECUT2 and ETV4 in exhausted CD8 + T cells, TIGIT and CTL4 high expression in regulatory T cells. Our results highlight the heterogeneity of CD45 + immune cells in the TME and provide testable hypotheses about the cell types and genes that define the TME., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhao, Zhang, Tu, Chen, Peng, Ni, Zhu, Cheng, Li, Xiao, Yu, Lu, Chen, Li, Tang, Wang, Luo, Zhang, Che, Li, Wang and Xie.)

BRAF and MEK inhibitors significantly prolong progression-free survival in patients with BRAF mutant melanoma. However, most patients quickly develop drug resistance. The mechanism of drug resistance is complicated and remains to be further explored. Here, we found that inhibition of the MAPK pathway activates the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway, whereas JAK2 inhibitors that inhibit the JAK2/STAT3 pathway activate the MAPK pathway, suggesting a crosstalk between these two pathways in BRAF mutant melanoma cells. Reactivation of the MAPK pathway occurs in most drug-resistant patients with BRAF mutations. Therefore, dual inhibition of the MAPK and JAK2/STAT3 pathways is critical for the treatment of BRAF mutant melanoma. However, we found that the combination of BRAF, MEK inhibitors, and JAK2 or STAT3 inhibitors could not simultaneously inhibit the MAPK and JAK2/STAT3 pathways in BRAF mutant melanoma cells. Subsequently, we found that a combination of all three MAPK pathway inhibitors-BRAF, MEK, and ERK inhibitors-with JAK2 or STAT3 inhibitors can dually inhibit the MAPK and JAK2/STAT3 pathways, showing a significant inhibition of the growth of BRAF mutant melanoma cells compared with either treatment alone. Therefore, dual inhibition of MAPK and JAK2/STAT3 pathways may be a novel strategy for the treatment of BRAF mutant tumors., (© 2020 The Author(s).)

Background: Ion channels are a large family of transmembrane proteins, accessible by soluble membrane-impermeable molecules, and thus are targets for development of therapeutic drugs. Ion channels are the second most common target for existing drugs, after G protein-coupled receptors, and are expected to make a big impact on precision medicine in many different diseases including wound repair and regeneration. Research has shown that endogenous bioelectric signaling mediated by ion channels is critical in non-mammalian limb regeneration. However, the role of ion channels in regeneration of limbs in mammalian systems is not yet defined., Methods: To explore the role of potassium channels in limb wound repair and regeneration, the hindlimbs of mouse embryos were amputated at E12.5 when the wound is expected to regenerate and E15.5 when the wound is not expected to regenerate, and gene expression of potassium channels was studied., Results: Most of the potassium channels were downregulated, except for the potassium channel kcnj8 (Kir6.1) which was upregulated in E12.5 embryos after amputation., Conclusion: This study provides a new mouse limb regeneration model and demonstrates that potassium channels are potential drug targets for limb wound healing and regeneration., (© The Author(s) [2019]. Published by Oxford University Press on behalf of West China School of Medicine & West China Hospital of Sichuan University.)

Cancer is a heterogeneous disease with unique genomic and phenotypic features that differ between individual patients and even among individual tumor regions. In recent years, large-scale genomic studies and new next-generation sequencing technologies have uncovered more scientific details about tumor heterogeneity, with significant implications for the choice of specific molecular biomarkers and clinical decision making. Genomic heterogeneity significantly contributes to the generation of a diverse cell population during tumor development and progression, representing a determining factor for variation in tumor treatment response. It has been considered a prominent contributor to therapeutic failure, and increases the likelihood of resistance to future therapies in most common cancers. The understanding of molecular heterogeneity in cancer is a fundamental component of precision oncology, enabling the identification of genomic alteration of key genes and pathways that can be targeted therapeutically. Here, we review the emerging knowledge of tumor genomics and heterogeneity, as well as potential implications for precision medicine in cancer treatment and new therapeutic discoveries. An analysis and interpretation of the TCGA database was included.

Microfluidic impedance pulse sensor has emerged as an easily handled and low-cost platform in the electrical analysis of biological cells. In the conventional method, impedance sensor demanded expensive patterning metal electrodes on the substrate, which are directly in touch with electrolytes in order to measure the microfluidic channel impedance change. In this article, a cost-effective microfluidic impedance sensor built upon a dielectric film coated printed circuit board is introduced. Impedance electrodes are protected by a dielectric film layer from electrochemical erosion between electrodes and electrolyte. Human red blood cells from adult and neonatal were utilized to demonstrate the feasibility of the proposed device in the electroanalysis of biological cells., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

An effective blood-based method for the diagnosis and prognosis of hepatocellular carcinoma (HCC) has not yet been developed. Circulating tumour DNA (ctDNA) carrying cancer-specific genetic and epigenetic aberrations may enable a noninvasive 'liquid biopsy' for diagnosis and monitoring of cancer. Here, we identified an HCC-specific methylation marker panel by comparing HCC tissue and normal blood leukocytes and showed that methylation profiles of HCC tumour DNA and matched plasma ctDNA are highly correlated. Using cfDNA samples from a large cohort of 1,098 HCC patients and 835 normal controls, we constructed a diagnostic prediction model that showed high diagnostic specificity and sensitivity (P < 0.001) and was highly correlated with tumour burden, treatment response, and stage. Additionally, we constructed a prognostic prediction model that effectively predicted prognosis and survival (P < 0.001). Together, these findings demonstrate in a large clinical cohort the utility of ctDNA methylation markers in the diagnosis, surveillance, and prognosis of HCC.

Rationale: Osteosarcoma is the most common malignant bone tumor in children and adolescents. Pulmonary metastases lead to a significantly increased risk of death. Apatinib, a new potent oral small-molecule tyrosine kinase inhibitor targeting the intracellular domain of vascular endothelial growth factor receptor 2 (VEGFR-2), shows survival benefits in treating advanced or metastatic gastric adenocarcinoma, non-squamous non-small cell lung cancer and metastatic breast cancer. However, its efficacy in metastatic osteosarcoma has not been reported yet., Patient Concerns: Herein, we presented a 50-year-old man patient who visited hospital due to local bone pain in the left leg., Diagnoses: He was initially diagnosed with osteoblastic osteosarcoma., Interventions: The patient suffered repeated resection surgeries but developed multiple lung metastases. Positive staining for CD31, CD34, and VEGFR-2 were detected in the tumor section. As he refused to receive chemotherapy due to concerns regarding the chemotherapy toxicities and sorafenib due to high cost, apatinib was given at a dose of 500 mg daily., Outcomes: Eleven months following apatinib administration, the patient achieved a partial response according to the RECIST 1.1 standard. No severe toxicity or drug-related side effect was observed during the treatment., Lessons: Therefore, apatinib could be a new option for the treatment of metastatic osteosarcoma. Clinical trials are required to further confirm the efficacy and safety of apatinib in treating pulmonary metastases from osteosarcoma.

Vasculopathy is a major complication of diabetes. Impaired mitochondrial bioenergetics and biogenesis due to oxidative stress are a critical causal factor for diabetic endothelial dysfunction. Sirt1, an NAD + -dependent enzyme, is known to play an important protective role through deacetylation of many substrates involved in oxidative phosphorylation and reactive oxygen species generation. Mesenchymal stem cell-conditioned medium (MSC-CM) has emerged as a promising cell-free therapy due to the trophic actions of mesenchymal stem cell (MSC)-secreted molecules. In the present study, we investigated the therapeutic potential of MSC-CMs in diabetic endothelial dysfunction, focusing on the Sirt1 signalling pathway and the relevance to mitochondrial function. We found that high glucose-stimulated MSC-CM attenuated several glucotoxicity-induced processes, oxidative stress and apoptosis of endothelial cells of the human umbilical vein. MSC-CM perfusion in diabetic rats ameliorated compromised aortic vasodilatation and alleviated oxidative stress in aortas. We further demonstrated that these effects were dependent on improved mitochondrial function and up-regulation of Sirt1 expression. MSC-CMs activated the phosphorylation of phosphoinositide 3-kinase (PI3K) and protein kinase B (Akt), leading to direct interaction between Akt and Sirt1, and subsequently enhanced Sirt1 expression. In addition, both MSC-CM and Sirt1 activation could increase the expression of peroxisome proliferator-activated receptor γ co-activator-1α (PGC-1α), as well as increase the mRNA expression of its downstream, mitochondrial, biogenesis-related genes. This indirect regulation was mediated by activation of AMP-activated protein kinase (AMPK). Overall our findings indicated that MSC-CM had protective effects on endothelial cells, with respect to glucotoxicity, by ameliorating mitochondrial dysfunction via the PI3K/Akt/Sirt1 pathway, and Sirt1 potentiated mitochondrial biogenesis, through the Sirt1/AMPK/PGC-1α pathway., (© 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.)

Decitabine, an epigenetic modifier that reactivates genes otherwise suppressed by DNA promoter methylation, is effective for some, but not all cancer patients, especially those with solid tumors. It is commonly recognized that to overcome resistance and improve outcome, treatment should be guided by tumor biology, which includes genotype, epigenotype, and gene expression profile. We therefore took an integrative approach to better understand melanoma cell response to clinically relevant dose of decitabine and identify complementary targets for combined therapy. We employed eight different melanoma cell strains, determined their growth, apoptotic and DNA damage responses to increasing doses of decitabine, and chose a low, clinically relevant drug dose to perform whole-genome differential gene expression, bioinformatic analysis, and protein validation studies. The data ruled out the DNA damage response, demonstrated the involvement of p21(Cip1) in a p53-independent manner, identified the TGFbeta pathway genes CLU and TGFBI as markers of sensitivity to decitabine and revealed an effect on histone modification as part of decitabine-induced gene expression. Mutation analysis and knockdown by siRNA implicated activated beta-catenin/MITF, but not BRAF, NRAS or PTEN mutations as a source for resistance. The importance of protein stability predicted from the results was validated by the synergistic effect of Bortezomib, a proteasome inhibitor, in enhancing the growth arrest of decitabine in otherwise resistant melanoma cells. Our integrative analysis show that improved therapy can be achieved by comprehensive analysis of cancer cells, identified biomarkers for patient's selection and monitoring response, as well as targets for improved combination therapy.