Caffeic acid phenethyl ester suppresses metastasis of breast cancer cells by inactivating FGFR1 via MD2.

BACKGROUND: Tumor metastasis is the main cause of death for breast cancer patients. Caffeic acid phenethyl ester (CAPE) has strong anti-tumor effects with very low toxicity and may be a potential candidate drug. However, the anti-metastatic effect and molecular mechanism of CAPE on breast cancer need more research. METHODS: MCF-7 and MDA-MB-231 breast cancer cells were used here. Wound healing and Transwell assay were used for migration and invasion detection. Western blot and RT-qPCR were carried out for the epithelial-to-myofibroblast transformation (EMT) process investigation. Western blot and immunofluorescence were performed for fibroblast growth factor receptor1 (FGFR1) phosphorylation and nuclear transfer detection. Co-immunoprecipitation was used for the FGFR1/myeloid differentiation protein2 (MD2) complex investigation. RESULTS: Our results suggested that CAPE blocks the migration, invasion, and EMT process of breast cancer cells. Mechanistically, CAPE inhibits FGFR1 phosphorylation and nuclear transfer while overexpression of FGFR1 reduces the anti-metastasis effect of CAPE. Further, we found that FGFR1 is bound to MD2, and silencing MD2 inhibits FGFR1 phosphorylation and nuclear transfer as well as cell migration and invasion. CONCLUSION: This study illustrated that CAPE restrained FGFR1 activation and nuclear transfer through MD2/FGFR1 complex inhibition and showed good inhibitory effects on the metastasis of breast cancer cells.

Identification and validation of the microRNAs and hub genes for pancreatic ductal adenocarcinoma by an integrated bioinformatic analysis.

Background: In the progression of pancreatic ductal adenocarcinoma (PDAC), aberrant micro RNAs (miRNAs) expression plays a crucial role. This study sought to identify and validate the key miRNAs and potential target genes involved in PDAC. A bioinformatic analysis was conducted to determine their potential use as biomarkers and therapeutic targets. Methods: Gene profiling data sets (GSE41372 and GSE32688) were retrieved from the Gene Expression Omnibus database. Differentially expressed miRNAs (DEMs) with a P value <0.05, and |fold change| >2 was identified. The prognostic value of the DEMs was accessed using the online server Kaplan-Meier plotter. Further, gene ontology terms and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed using DAVID 6.7. The protein-protein interaction analyses were conducted with STRING, and miRNA-hub gene networks were constructed using Cytoscape software. The PDAC cells were transfected with miRNA inhibitors or mimics. Cell Counting Kit-8 assays and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were used to examine cell proliferation and apoptosis, respectively. Wound-healing assays were performed to evaluate cell migration. Results: Three DEMs (hsa-miR-21-5p, hsa-miR-135b-5p, and hsa-miR-222-3p) were identified. High expression levels of hsa-miR-21-5p, hsa-miR-135b-5p, or hsa-miR-222-3p predicted poor overall survival in PDAC patients. The pathway analysis revealed that the predicted target genes of the DEMs were closely related to several signaling pathways (including 'pathways in cancer', 'miRNAs in cancer', 'platinum drug resistance', 'lipid and atherosclerosis', and 'MAPK signaling pathway'). The MYC proto-oncogene (MYC), phosphate and tensin homolog gene (PTEN), poly(ADP-ribose) polymerase 1 (PARP1), von Hippel-Lindau (VHL), and fork head box p3 (FOXP3) were identified as potential target genes. The inhibition of hsa-miR-21-5p, hsa-miR-135b-5p, or hsa-miR-222-3p expression decreased cell proliferation. The overexpression of hsa-miR-21-5p, hsa-miR-135b-5p, or hsa-miR-222-3p facilitated PDAC cell migration. Conclusions: This study constructed the miRNA-hub gene network, which provides novel insights into the PDAC progression. Although further research is required, our results offer clues for new potential prognostic markers and therapeutic targets of PDAC.

ASPM promotes migration and invasion of anaplastic thyroid carcinoma by stabilizing KIF11.

Abnormal spindle-like microcephaly-associated (ASPM) protein is crucial to the mitotic spindle function during cell replication and tumor progression in multiple tumor types. However, the effect of ASPM in anaplastic thyroid carcinoma (ATC) has not yet been understood. The present study is to elucidate the function of ASPM in the migration and invasion of ATC. ASPM expression is incrementally upregulated in ATC tissues and cell lines. Knockout (KO) of ASPM pronouncedly attenuates the migration and invasion of ATC cells. ASPM KO significantly reduces the transcript levels of Vimentin, N-cadherin, and Snail and increases E-cadherin and Occludin, thereby inhibiting epithelial-to-mesenchymal transition (EMT). Mechanistically, ASPM regulates the movement of ATC cells by inhibiting the ubiquitin degradation of KIF11 and thus stabilizing it via direct binding to it. Moreover, xenograft tumors in nude mice proved that KO of ASPM could ameliorate tumorigenesis and tumor growth accompanied by a decreased protein expression of KIF11 and an inhibition of EMT. In conclusion, ASPM is a potentially useful therapeutic target for ATC. Our results also reveal a novel mechanism by which ASPM inhibits the ubiquitin process in KIF11.

Cost-effectiveness of PARP inhibitors in malignancies: A systematic review.

OBJECTIVES: Poly (ADP-ribose) polymerase inhibitor (PARPi) have become a mainstay for the treatment of BRCA-mutant malignancies. PARPis are likely to be more effective but also bring an increase in costs. Thus, we aimed at evaluating the cost effectiveness of PARPis in the treatment of malignancies. METHODS: Studies of cost effectiveness of PARPis were searched from PubMed, Web of Science, and Cochrane Library. Key information was extracted from the identified studies and reviewed. Quality of the included studies was evaluated using Quality of Health Economic Studies (QHES) instrument. Modeling techniques, measurement of parameters and uncertainty analysis were analyzed across studies. Interventions and cost-effectiveness results were reported stratified by patient population. RESULTS: Among the 25 studies identified, we included 17 on ovarian cancer, 2 on breast cancer, 3 on pancreatic cancer, and 3 on prostate cancer that involved olaparib, niraparib, rucaparib, and talazoparib. All studies had a QHES score of above 75. In the maintenance therapy of ovarian cancer, additional administration of olaparib was cost-effective for newly diagnosed patients after first-line platinum-based chemotherapy but was not cost-effective for platinum-sensitive recurrent patients in majority studies. However, the economic value of other PARPis in ovarian cancer as well as all PARPis in other tumors remained controversial. Cost-effectiveness of PARPi was primarily impacted by the costs of PARPi, survival time, health utility and discount rate. Moreover, genetic testing improved the cost-effectiveness of PARPi treatment. CONCLUSIONS: PARPi is potentially cost-effective for patients with ovarian, pancreatic, or prostate cancer. Genetic testing can improve the cost-effectiveness of PARPi.

A Novel Risk Model Based on Autophagy-Related LncRNAs Predicts Prognosis and Indicates Immune Infiltration Landscape of Patients With Cutaneous Melanoma.

Cutaneous melanoma (CM) is a malignant tumor with a high incidence rate and poor prognosis. Autophagy plays an essential role in the development of CM; however, the role of autophagy-related long noncoding RNAs (lncRNAs) in this process remains unknown. Human autophagy-related genes were extracted from the Human Autophagy Gene Database and screened for autophagy-related lncRNAs using Pearson correlation. Multivariate Cox regression analysis was implemented to identify ten autophagy-related lncRNAs associated with prognosis, and a risk model was constructed. The Kaplan-Meier survival curve showed that the survival probability of the high-risk group was lower than that of the low-risk group. A novel predictive model was constructed to investigate the independent prognostic value of the risk model. The nomogram results showed that the risk score was an independent prognostic signature that distinguished it from other clinical characteristics. The immune infiltration landscape of the low-risk and high-risk groups was further investigated. The low-risk groups displayed higher immune, stromal, and ESTIMATE scores and lower tumor purity. The CIBERSORT and single sample gene set enrichment analysis (ssGSEA) algorithms indicated a notable gap in immune cells between the low- and high-risk groups. Ten autophagy-related lncRNAs were significantly correlated with immune cells. Finally, Gene Set Enrichment Analysis (GSEA) and Gene Set Variation Analysis (GSVA) results demonstrated that autophagy-related lncRNA-mediated and immune-related signaling pathways are crucial factors in regulating CM. Altogether, these data suggest that constructing a risk model based on ten autophagy-related lncRNAs can accurately predict prognosis and indicate the tumor microenvironment of patients with CM. Thus, our study provides a new perspective for the future clinical treatment of CM.

Luteolin attenuated cisplatin-induced cardiac dysfunction and oxidative stress via modulation of Keap1/Nrf2 signaling pathway.

Cardiovascular complications are a well-documented limitation of cancer chemotherapy. Cisplatin-induced cardiotoxicity threatens the health and life of patients, and limits the application of cisplatin. Oxidative stress is the main mechanism underlying cisplatin-induced cardiac toxicity. Luteolin (Lut) has been reported to possess cardioprotective properties by activating nuclear factor-E2-related factor 2 (Nrf2) -mediated antioxidant response. However, the effect of Lut on cisplatin-induced cardiac damage remains unclear. In this study, we revealed that Lut exerted a protective effect against cisplatin-induced cardiac dysfunction and injury in vivo. In HL-1 cells, Lut was observed to dramatically reduce cisplatin-induced apoptosis and oxidative stress by modulating the Kelch-like epichlorohydrin-associated protein 1 (Keap1)/Nrf2 pathway. Altogether, these findings suggested that Lut showed promise in attenuating cisplatin-induced cardiac injury and might be considered a protective drug candidate for chemotherapy-associated cardiovascular complications.

MD2 blockage prevents the migration and invasion of hepatocellular carcinoma cells via inhibition of the EGFR signaling pathway.

BACKGROUND: The toll-like receptor (TLR) is an emerging signaling pathway in tumor invasion and metastasis. The activation of TLRs requires specific accessory proteins, such as the small secreted glycoprotein myeloid differentiation protein 2 (MD2), which contributes to ligand responsiveness. However, the role of MD2 in tumorigenesis and metastasis has rarely been reported. This study aimed to investigate the effects and underlying mechanisms of MD2 on the proliferation, migration, and invasion of hepatocellular carcinoma (HCC). METHODS: Cell counting kit 8 (CCK8), cell colony formation, wound healing, and transwell assays were conducted to determine cell viability, proliferation, migration, and invasion, respectively. Quantitative real-time PCR (qRT-PCR) was performed to assess the expression of MD2 in HCC cell lines and human normal liver cell lines as well as the silencing efficiency of MD2 blockage. Western blot and qRT-PCR assays were performed to detect the protein and mRNA expression levels of epithelial mesenchymal transformation (EMT) markers and epidermal growth factor receptor (EGFR) signaling molecules. RESULTS: MD2 was highly expressed in HCC tissues and cell lines. High expression of MD2 was associated with poor prognosis of HCC patients. In addition, MD2 silencing slightly inhibited the proliferation of HepG2 and HCCLM3, and significantly suppressed cell migration and invasion. Furthermore, MD2 blockage could distinctly prevent the EMT process by increasing the protein and mRNA levels of E-cadherin and Occludin, and decreasing the levels of Vimentin, N-cadherin, and Snail. Finally, the phosphorylation level of EGFR as well as its downstream molecular Src, Akt, I-κBα, and p65 were downregulated in HCC cells with MD2 silencing. CONCLUSIONS: Our findings suggest that high expression of MD2 may affect the EMT, migration, and invasion via modulation of the EGFR pathway in HCC cells.

HN1 promotes tumor growth and metastasis of anaplastic thyroid carcinoma by interacting with STMN1.

Anaplastic thyroid carcinoma (ATC) is one of the most aggressive malignancies frequently associated with extrathyroidal extension and metastasis through pathways that remain unclear. Analysis of the cancer genome atlas (TCGA) database and an independent cohort showed that the expression of hematological and neurological expressed 1 (HN1) was higher in thyroid cancers than in normal tissues, and negatively correlated with progression-free survival. RT-PCR and immunohistochemistry revealed higher HN1 expression in ATC compared to healthy tissues and papillary thyroid carcinoma (PTC). HN1 knockdown attenuated migration and invasion of ATC cells, whereas HN1 overexpression increased migration and invasion of PTC cells. HN1 reduced the acetylation of α-tubulin and promoted progression through epithelial-mesenchymal transition of ATC cells and mouse xenografts. HN1 knockdown significantly attenuated TGF-ß-induced mesenchymal phenotype, and inhibited tumor formation and growth of ATC xenografts in nude mice. Loss of STMN1 decreased the malignant potential of HN1, whereas HN1 knockdown in combination with STMN1 overexpression restored the aggressive properties of ATC cells. HN1 increased STMN1 mRNA expression, and prevented STMN1 ubiquitination and subsequent degradation. These results demonstrate that HN1 interacts with STMN1 and drives ATC aggressiveness.

Cost-effectiveness of pembrolizumab for treatment of platinum-resistant recurrent or metastatic head and neck squamous cell carcinoma in China: an economic analysis based on a randomised, open-label, phase III trial.

BACKGROUND: Pembrolizumab was recently demonstrated to have survival benefit in patients with recurrent or metastatic head and neck squamous cell carcinoma (r/mHNSCC). However, the cost-effectiveness of pembrolizumab versus chemotherapy in China remains uncertain. OBJECTIVE: This analysis aimed to describe the cost-effectiveness of pembrolizumab versus standard-of-care (SOC) therapy in r/mHNSCC in China. DESIGN: A Markov model consisting of three health states (stable, progressive and dead) was developed to compare the cost and effectiveness of pembrolizumab with SOC in platinum-resistant r/mHNSCC. Model inputs for transition probabilities and toxicity were collected from the KEYNOTE-040 trial, while health utilities were estimated from a literature review. Cost data were acquired for the payer's perspective in China. Costs and outcomes were discounted at an annual rate of 3.0%. Sensitivity analyses were conducted to test the uncertainties surrounding model parameters. OUTCOME MEASURES: The primary outcome was incremental cost-effectiveness ratios (ICERs), which were calculated as the cost per quality-adjusted life years (QALYs). RESULTS: The total mean cost of pembrolizumab and SOC was US$45 861 and US$41 950, respectively. As for effectiveness, pembrolizumab yielded 0.31 QALYs compared with 0.25 QALYs for SOC therapy. The ICER for pembrolizumab versus SOC was US$65 186/QALY, which was higher than the willingness-to-pay threshold (WTP) of US$28 130/QALY in China. The univariate sensitivity analysis indicated that utility values for progressive state, probability from stable to progressive in the SOC group, as well as cost of pembrolizumab were the three most influential variables on ICER. The probabilistic sensitivity analysis demonstrated that standard therapy was more likely to be cost-effective compared with pembrolizumab at a WTP value of US$28 130/QALY. Results were robust across both univariate analysis and probabilistic sensitivity analysis. CONCLUSIONS: Pembrolizumab is not likely to be a cost-effective strategy compared with SOC therapy in patients with platinum-resistant r/mHNSCC in China. TRIAL REGISTRATION NUMBER: NCT02252042; Post-results.

Correction to: Analysis of dynamic molecular networks for pancreatic ductal adenocarcinoma progression.

[This corrects the article DOI: 10.1186/s12935-018-0718-5.].

MD2 activation by direct AGE interaction drives inflammatory diabetic cardiomyopathy.

Hyperglycemia activates toll-like receptor 4 (TLR4) to induce inflammation in diabetic cardiomyopathy (DCM). However, the mechanisms of TLR4 activation remain unclear. Here we examine the role of myeloid differentiation 2 (MD2), a co-receptor of TLR4, in high glucose (HG)- and diabetes-induced inflammatory cardiomyopathy. We show increased MD2 in heart tissues of diabetic mice and serum of human diabetic subjects. MD2 deficiency in mice inhibits TLR4 pathway activation, which correlates with reduced myocardial remodeling and improved cardiac function. Mechanistically, we show that HG induces extracellular advanced glycation end products (AGEs), which bind directly to MD2, leading to formation of AGEs-MD2-TLR4 complex and initiation of pro-inflammatory pathways. We further detect elevated AGE-MD2 complexes in heart tissues and serum of diabetic mice and human subjects with DCM. In summary, we uncover a new mechanism of HG-induced inflammatory responses and myocardial injury, in which AGE products directly bind MD2 to drive inflammatory DCM.

Kaempferol attenuated cisplatin-induced cardiac injury via inhibiting STING/NF-κB-mediated inflammation.

Cardiovascular complications have been well documented as the downside to conventional cancer chemotherapy. As a notable side effect of cisplatin, cardiotoxicity represents a major obstacle to the successful treatment of cancer. It has been reported that kaempferol (KPF) possesses cardioprotective and anti-inflammatory qualities. However, the effect of KPF on cardiac damage caused by conventional cancer chemotherapy remains unclear. In this study, we clarified the protective effect of KPF on cisplatin-induced heart injury, and conducted in-depth research on the molecular mechanism underlying this effect. The results showed that KPF protected against cardiac dysfunction and injury induced by cisplatin in vivo. In H9c2 cells, KPF dramatically reduced cispaltin-induced apoptosis and inflammatory response by modulating STING/NF-κB pathway. In conclusion, these results showed that KPF had great potential in attenuating cisplatin-induced cardiac injury. Besides, greater emphasis should be placed in the future on natural active compounds containing KPF with anti-inflammatory effects for the treatment of these diseases.

Integrated Bioinformatics Analysis of Master Regulators in Anaplastic Thyroid Carcinoma.

Anaplastic thyroid carcinoma (ATC) is one of the most aggressive and rapidly lethal tumors. However, limited advances have been made to prolong the survival and to reduce the mortality over the last decades. Therefore, identifying the master regulators underlying ATC progression is desperately needed. In our present study, three datasets including GSE33630, GSE29265, and GSE65144 were retrieved from Gene Expression Omnibus with a total of 32 ATC samples and 78 normal thyroid tissues. A total of 1804 consistently changed differentially expressed genes (DEGs) were identified from three datasets. KEGG pathways enrichment suggested that upregulated DEGs were mainly enriched in ECM-receptor interaction, cell cycle, PI3K-Akt signaling pathway, focal adhesion, and p53 signaling pathway. Furthermore, key gene modules in PPI network were identified by Cytoscape plugin MCODE and they were mainly associated with DNA replication, cell cycle process, collagen fibril organization, and regulation of leukocyte migration. Additionally, TOP2A, CDK1, CCNB1, VEGFA, BIRC5, MAPK1, CCNA2, MAD2L1, CDC20, and BUB1 were identified as hub genes of the PPI network. Interestingly, module analysis showed that 8 out of 10 hub genes participated in Module 1 network and more than 70% genes of Module 2 consisted of collagen family members. Notably, transcription factors (TFs) regulatory network analysis indicated that E2F7, FOXM1, and NFYB were master regulators of Module 1, while CREB3L1 was the master regulator of Module 2. Experimental validation showed that CREB3L1, E2F7, and FOXM1 were significantly upregulated in ATC tissue and cell line when compared with normal thyroid group. In conclusion, the TFs regulatory network provided a more detail molecular mechanism underlying ATC occurrence and progression. TFs including E2F7, FOXM1, CREB3L1, and NFYB were likely to be master regulators of ATC progression, suggesting their potential role as molecular therapeutic targets in ATC treatment.

Blockade of myeloid differentiation 2 attenuates diabetic nephropathy by reducing activation of the renin-angiotensin system in mouse kidneys.

BACKGROUND AND PURPOSE: Both innate immunity and the renin-angiotensin system (RAS) play important roles in the pathogenesis of diabetic nephropathy (DN). Myeloid differentiation factor 2 (MD2) is a co-receptor of toll-like receptor 4 (TLR4) in innate immunity. While TLR4 is involved in the development of DN, the role of MD2 in DN has not been characterized. It also remains unclear whether the MD2/TLR4 signalling pathway is associated with RAS activation in diabetes. EXPERIMENTAL APPROACH: MD2 was blocked using siRNA or the low MW inhibitor, L6H9, in renal proximal tubular cells (NRK-52E cells) exposed to high concentrations of glucose (HG). In vivo, C57BL/6 and MD2-/- mice were injected with streptozotocin to induce Type 1 diabetes and nephropathy. KEY RESULTS: Inhibition of MD2 by genetic knockdown or the inhibitor L6H9 suppressed HG-induced expression of ACE and angiotensin receptors and production of angiotensin II in NRK-52E cells, along with decreased fibrosis markers (TGF-ß and collagen IV). Inhibition of the MD2/TLR4-MAPKs pathway did not affect HG-induced renin overproduction. In vivo, using the streptozotocin-induced diabetic mice, MD2 was overexpressed in diabetic kidney. MD2 gene knockout or L6H9 attenuated renal fibrosis and dysfunction by suppressing local RAS activation and inflammation. CONCLUSIONS AND IMPLICATIONS: Hyperglycaemia activated the MD2/TLR4-MAPKs signalling cascade to induce renal RAS activation, leading to renal fibrosis and dysfunction. Pharmacological inhibition of MD2 may be considered as a therapeutic approach to mitigate DN and the low MW inhibitor L6H9 could be a candidate for such therapy.

[Identification of key pathways and drug repurposing for anaplastic thyroid carcinoma by integrated bioinformatics analysis].

OBJECTIVE: To identify hub genes and key pathways associated with anaplastic thyroid carcinoma (ATC), and to explore possible intervention strategy. METHODS: The differentially expressed genes (DEGs) in ATC were identified by Gene Expression Omnibus (GEO) combined with using R language; the pathway enrichment of DEGs were performed by using Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO). The protein-protein interaction (PPI) network of DEGs was constructed by STRING database and visualized by Cytoscape. Furthermore, the hub genes and key nodes were calculated by MCODE. Finally, the drug repurposing was performed by L1000CDS2. RESULTS: A total of 2087 DEGs were identified. The DEGs were clustered based on functions and pathways with significant enrichment analysis, among which PI3K-Akt signaling pathway, p53 signaling pathway, inflammatory response, extracellular matrix organization were significantly upregulated. The PPI network was constructed and the most significant three modules and nine genes were filtered. Twenty-two potential compounds were repurposed for ATC treatment. CONCLUSIONS: Using integrated bioinformatics analysis, we have identified hub genes and key pathways in ATC, and provide novel strategy for the treatment of ATC.

Author Correction: Saturated palmitic acid induces myocardial inflammatory injuries through direct binding to TLR4 accessory protein MD2.

This corrects the article DOI: 10.1038/ncomms13997.

Effect of hypoglycemic agents on survival outcomes of lung cancer patients with diabetes mellitus: A meta-analysis.

BACKGROUND: To assess the association between hypoglycemic agents and prognosis of lung cancer patients with diabetes. METHODS: A comprehensive literature search was performed in PubMed, Web of Science, Embase, and Cochrane Library until May 2017. The search yielded 2593 unique citations, of which 18 articles met inclusion criteria. The hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated by a fixed-effects or random-effects model. RESULTS: The pooled HRs favoring metformin users were 0.77 for overall survival (OS) (n = 15, 95% CI: 0.68-0.86) and 0.50 for disease-free survival (n = 5, 95% CI: 0.39-0.64). One study assessed the relationship between metformin and cancer-specific survival (CSS), reporting no significant results. No significant association between insulin and OS (n = 2, HR: 0.95, 95% CI: 0.79-1.13) or CSS (n = 2, HR: 1.03, 95% CI: 0.76-1.41) was noted. One study evaluated association of sulfonylureas with lung cancer survival and reported no clinical benefit (HR: 1.10, 95% CI: 0.87-1.40). One study reported no association of thiazolidinediones with lung cancer survival (HR: 1.04, 95% CI: 0.65-1.66). CONCLUSIONS: This meta-analysis demonstrated that metformin exposure might improve survival outcomes in lung cancer patients with diabetes.

Effects of metformin on survival outcomes of pancreatic cancer patients with diabetes: A meta-analysis.

Pancreatic cancer risk is reduced by metformin treatment in patients with diabetes. However, the effect of metformin on pancreatic cancer overall survival is unclear. The aim of the present study was to determine the association between metformin and clinical outcomes of pancreatic cancer patients with diabetes. An electronic and manual search was conducted using PubMed, Web of Science, Medline-Ovid and Cochrane Library databases between the beginning and March 31, 2017. A total of 8 studies consisting of 4,293 patients with pancreatic cancer with diabetes were included, comprising 2,033 patients who had received metformin and 2,260 patients who had not. The meta-analysis showed that metformin was associated with a relative survival benefit in pancreatic cancer patients [hazard ratio (HR), 0.81; 95% confidence interval (CI), 0.70-0.93]. These associations were also observed in subgroups of Asian countries 0.64 (95% CI, 0.52-0.80) and Western countries 0.88 (95% CI, 0.82-0.95), as well as diabetes (no indication of diabetes type). Excluding the studies considered as be prone to immortal time bias resulted in HRs (95% CIs) of 0.86 (0.69-1.07). The results of this study support the notion that the use of metformin may improve the overall survival of patients with pancreatic cancer with concurrent diabetes. However, the proposed beneficial effect of metformin on pancreatic cancer survival may be based on immortal time bias. Further carefully designed studies with high quality are warranted to confirm this efficacy.

Analysis of dynamic molecular networks for pancreatic ductal adenocarcinoma progression.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest solid tumors. The rapid progression of PDAC results in an advanced stage of patients when diagnosed. However, the dynamic molecular mechanism underlying PDAC progression remains far from clear. METHODS: The microarray GSE62165 containing PDAC staging samples was obtained from Gene Expression Omnibus and the differentially expressed genes (DEGs) between normal tissue and PDAC of different stages were profiled using R software, respectively. The software program Short Time-series Expression Miner was applied to cluster, compare, and visualize gene expression differences between PDAC stages. Then, function annotation and pathway enrichment of DEGs were conducted by Database for Annotation Visualization and Integrated Discovery. Further, the Cytoscape plugin DyNetViewer was applied to construct the dynamic protein-protein interaction networks and to analyze different topological variation of nodes and clusters over time. The phosphosite markers of stage-specific protein kinases were predicted by PhosphoSitePlus database. Moreover, survival analysis of candidate genes and pathways was performed by Kaplan-Meier plotter. Finally, candidate genes were validated by immunohistochemistry in PDAC tissues. RESULTS: Compared with normal tissues, the total DEGs number for each PDAC stage were 994 (stage I), 967 (stage IIa), 965 (stage IIb), 1027 (stage III), 925 (stage IV), respectively. The stage-course gene expression analysis showed that 30 distinct expressional models were clustered. Kyoto Encyclopedia of Genes and Genomes analysis indicated that the up-regulated DEGs were commonly enriched in five fundamental pathways throughout five stages, including pathways in cancer, small cell lung cancer, ECM-receptor interaction, amoebiasis, focal adhesion. Except for amoebiasis, these pathways were associated with poor PDAC overall survival. Meanwhile, LAMA3, LAMB3, LAMC2, COL4A1 and FN1 were commonly shared by these five pathways and were unfavorable factors for prognosis. Furthermore, by constructing the stage-course dynamic protein interaction network, 45 functional molecular modules and 19 nodes were identified as featured regulators for all PDAC stages, among which the collagen family and integrins were considered as two main regulators for facilitating aggressive progression. Additionally, the clinical relevance analysis suggested that the stage IV featured nodes MLF1IP and ITGB4 were significantly correlated with shorter overall survival. Moreover, 15 stage-specific protein kinases were identified from the dynamic network and CHEK1 was particularly activated at stage IV. Experimental validation showed that MLF1IP, LAMA3 and LAMB3 were progressively increased from tumor initiation to progression. CONCLUSIONS: Our study provided a view for a better understanding of the dynamic landscape of molecular interaction networks during PDAC progression and offered potential targets for therapeutic intervention.

Inhibition of myeloid differentiation factor-2 attenuates obesity-induced cardiomyopathy and fibrosis.

Obesity causes cardiovascular diseases, including cardiac hypertrophy and remodeling, via chronic tissue inflammation. Myeloid differentiation factor-2 (MD2), a binding protein of lipopolysaccharide, is functionally essential for the activation of proinflammatory pathways in endotoxin-induced acute inflammatory diseases. Here we tested the hypothesis that MD2 plays a central role in obesity-induced cardiomyopathy. Wildtype or MD2 knockout mice were fed with a high fat diet (HFD) or normal diet (Control) for total 16weeks, and MD2 inhibitor L6H21 (20mg/kg) or vehicle (1% CMC-Na) were administered from the beginning of the 9th week. HFD induced significant weight gain and cardiac hypertrophy, with increased cardiac fibrosis and inflammation. L6H21 administration or MD2 knockout attenuated HFD-induced obesity, inflammation and cardiac remodeling. In vitro exposure of H9C2 cells to high lipids induced cell hypertrophy with activated JNK/ERK and NF-κB pathways, which was abolished by pretreatment of MD2 inhibitor L6H21. Our results demonstrate that MD2 is essential to obesity-related cardiac hypertrophy through activating JNK/ERK and NF-κB-dependent cardiac inflammatory pathways. Targeting MD2 would be a therapeutic approach to prevent obesity-induced cardiac injury and remodeling.