Epigenetics, TET proteins, and hypoxia in epithelial-mesenchymal transition and tumorigenesis

A dynamic model of inorganic arsenic-induced carcinogenesis reveals an epigenetic mechanism for epithelial-mesenchymal plasticity

Inorganic arsenic (iAs) causes cancer by initiating dynamic transitions between epithelial and mesenchymal cell phenotypes. These transitions transform normal cells into cancerous cells, and cancerous cells into metastatic cells. Most in vitro models assume that transitions between states are binary and complete, and do not consider the possibility that intermediate, stable cellular states might exist. In this paper, we describe a new, two-hit in vitro model of iAs-induced carcinogenesis that extends to 28 weeks of iAs exposure. Through week 17, the model faithfully recapitulates known and expected phenotypic, genetic, and epigenetic characteristics of iAs-induced carcinogenesis. By 28 weeks, however, exposed cells exhibit stable, intermediate phenotypes and epigenetic properties, and key transcription factor promoters (SNAI1, ZEB1) enter an epigenetically poised or bivalent state. These data suggest that key epigenetic transitions and cellular states exist during iAs-induced epithelial-to-mesenchymal transition (EMT), and that it is important for our in vitro models to encapsulate all aspects of EMT and the mesenchymal-to-epithelial transition (MET). In so doing, and by understanding the epigenetic systems controlling these transitions, we might find new, unexpected opportunities for developing targeted, cell state-specific therapeutics.

The journey of boswellic acids from synthesis to pharmacological activities

There has been a lot of interest in using naturally occurring substances to treat a wide variety of chronic disorders in recent years. From the gum resin of Boswellia serrata and Boswellia carteri, the pentacyclic triterpene molecules known as boswellic acid (BA) are extracted. We aimed to provide a detailed overview of the origins, chemistry, synthetic derivatives, pharmacokinetic, and biological activity of numerous Boswellia species and their derivatives. The literature searched for reports of B. serrata and isolated BAs having anti-cancer, anti-microbial, anti-inflammatory, anti-arthritic, hypolipidemic, immunomodulatory, anti-diabetic, hepatoprotective, anti-asthmatic, and clastogenic activities. Our results revealed that the cytotoxic and anticancer effects of B. serrata refer to its triterpenoid component, including BAs. Three-O-acetyl-11-keto-BA was the most promising cytotoxic molecule among tested substances. Activation of caspases, upregulation of Bax expression, downregulation of nuclear factor-kappa B (NF-kB), and stimulation of poly (ADP)-ribose polymerase (PARP) cleavage are the primary mechanisms responsible for cytotoxic and antitumor effects. Evidence suggests that BAs have shown promise in combating a wide range of debilitating disease conditions, including cancer, hepatic, inflammatory, and neurological disorders.

Circulating nucleosomes as potential biomarkers for cancer diagnosis and treatment monitoring

Nucleosomes play a crucial role in regulating gene expression through their composition and post-translational modifications. When cells die, intracellular endonucleases are activated and cleave chromatin into oligo- and mono-nucleosomes, which are then released into the body fluids. Studies have shown that the levels of nucleosomes are increased in serum and plasma in various cancer types, suggesting that analysis of circulating nucleosomes can provide an initial assessment of carcinogenesis. However, it should be noted that elevated serum nucleosome levels may not accurately diagnose certain tumor types, as increased cell death may occur in different pathological conditions. Nevertheless, detection of circulating nucleosomes and their histone modifications, along with specific tumor markers, can help diagnose certain types of cancer. Furthermore, monitoring changes in circulating nucleosome levels during chemotherapy or radiotherapy in patients with malignancies can provide valuable insights into clinical outcomes and therapeutic efficacy. The utilization of circulating nucleosomes as biomarkers is an exciting and emerging area of research, with the potential for early detection of various diseases and monitoring of treatment response. Integrating nucleosome-based biomarkers with existing ones may improve the specificity and sensitivity of current assays, offering the possibility of personalized precision medical treatment for patients.

TET protein inhibitors: Potential and limitations

TET proteins (methylcytosine dioxygenases) play an important role in the regulation of gene expression. Dysregulation of their activity is associated with many serious pathogenic states such as oncological diseases. Regulation of their activity by specific inhibitors could represent a promising therapeutic strategy. Therefore, this review describes various types of TET protein inhibitors in terms of their inhibitory mechanism and possible applicability. The potential and possible limitations of this approach are thoroughly discussed in the context of TET protein functionality in living systems. Furthermore, possible therapeutic strategies based on the inhibition of TET proteins are presented and evaluated, especially in the field of oncological diseases.

DNMT3B Is an Oxygen-Sensitive De Novo Methylase in Human Mesenchymal Stem Cells

The application of physiological oxygen (physoxia) concentrations is becoming increasingly commonplace within a mammalian stem cell culture. Human mesenchymal stem cells (hMSCs) attract widespread interest for clinical application due to their unique immunomodulatory, multi-lineage potential, and regenerative capacities. Descriptions of the impact of physoxia on global DNA methylation patterns in hMSCs and the activity of enzymatic machinery responsible for its regulation remain limited. Human bone marrow-derived mesenchymal stem cells (BM-hMSCs, passage 1) isolated in reduced oxygen conditions displayed an upregulation of SOX2 in reduced oxygen conditions vs. air oxygen (21% O2, AO), while no change was noted for either OCT-4 or NANOG. DNA methylation marks 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) showed decreases in 2% O2 environment (workstation) (2% WKS). DNMT3B (DNA methyltransferase 3B) and TET1 (Ten-eleven translocation enzyme 1) displayed reduced transcription in physoxia. Consistent with transcriptional downregulation, we noted increased promoter methylation levels of DNMT3B in 2% WKS accompanied by reduced DNMT3B and TET1 protein expression. Finally, a decrease in HIF1A (Hypoxia-inducible factor 1A) gene expression in 2% WKS environment correlated with protein levels, while HIF2A was significantly higher in physoxia correlated with protein expression levels vs. AO. Together, these data have demonstrated, for the first time, that global 5mC, 5hmC, and DNMT3B are oxygen-sensitive in hMSCs. Further insights into the appropriate epigenetic regulation within hMSCs may enable increased safety and efficacy development within the therapeutic ambitions.

Amnion-Derived Teno-Inductive Secretomes: A Novel Approach to Foster Tendon Differentiation and Regeneration in an Ovine Model

Regenerative medicine has greatly progressed, but tendon regeneration mechanisms and robust in vitro tendon differentiation protocols remain to be elucidated. Recently, tendon explant co-culture (CO) has been proposed as an in vitro model to recapitulate the microenvironment driving tendon development and regeneration. Here, we explored standardized protocols for production and storage of bioactive tendon-derived secretomes with an evaluation of their teno-inductive effects on ovine amniotic epithelial cells (AECs). Teno-inductive soluble factors were released in culture-conditioned media (CM) only in response to active communication between tendon explants and stem cells (CMCO). Unsuccessful tenogenic differentiation in AECs was noted when exposed to CM collected from tendon explants (CMFT) only, whereas CMCO upregulated SCXB, COL I and TNMD transcripts, in AECs, alongside stimulation of the development of mature 3D tendon-like structures enriched in TNMD and COL I extracellular matrix proteins. Furthermore, although the tenogenic effect on AECs was partially inhibited by freezing CMCO, this effect could be recovered by application of an in vivo-like physiological oxygen (2% O2) environment during AECs tenogenesis. Therefore, CMCO can be considered as a waste tissue product with the potential to be used for the development of regenerative bio-inspired devices to innovate tissue engineering application to tendon differentiation and healing.

Comprehensive Analysis of DNA Methylation and Prediction of Response to NeoadjuvantTherapy in Locally Advanced Rectal Cancer

The treatment for locally advanced rectal carcinomas (LARC) is based on neoadjuvant chemoradiotherapy (nCRT) and surgery, which results in pathological complete response (pCR) in up to 30% of patients. Since epigenetic changes may influence response to therapy, we aimed to identify DNA methylation markers predictive of pCR in LARC patients treated with nCRT. We used high-throughput DNA methylation analysis of 32 treatment-naïve LARC biopsies and five normal rectal tissues to explore the predictive value of differentially methylated (DM) CpGs. External validation was carried out with The Cancer Genome Atlas-Rectal Adenocarcinoma (TCGA-READ 99 cases). A classifier based on three-CpGs DM (linked to OBSL1, GPR1, and INSIG1 genes) was able to discriminate pCR from incomplete responders with high sensitivity and specificity. The methylation levels of the selected CpGs confirmed the predictive value of our classifier in 77 LARCs evaluated by bisulfite pyrosequencing. Evaluation of external datasets (TCGA-READ, GSE81006, GSE75546, and GSE39958) reproduced our results. As the three CpGs were mapped near to regulatory elements, we performed an integrative analysis in regions associated with predicted cis-regulatory elements. A positive and inverse correlation between DNA methylation and gene expression was found in two CpGs. We propose a novel predictive tool based on three CpGs potentially useful for pretreatment screening of LARC patients and guide the selection of treatment modality.

The Critical Role of Hypoxic Microenvironment and Epigenetic Deregulation in Esophageal Cancer Radioresistance

Esophageal cancer (EC) is the seventh most common cancer worldwide and the sixth leading cause of death, according to Globocan 2018. Despite efforts made for therapeutic advances, EC remains highly lethal, portending a five-year overall survival of just 15-20%. Hence, the discovery of new molecular targets that might improve therapeutic efficacy is urgently needed. Due to high proliferative rates and also the limited oxygen and nutrient diffusion in tumors, the development of hypoxic regions and consequent activation of hypoxia-inducible factors (HIFs) are a common characteristic of solid tumors, including EC. Accordingly, HIF-1α, involved in cell cycle deregulation, apoptosis, angiogenesis induction and proliferation in cancer, constitutes a predictive marker of resistance to radiotherapy (RT). Deregulation of epigenetic mechanisms, including aberrant DNA methylation and histone modifications, have emerged as critical factors in cancer development and progression. Recently, interactions between epigenetic enzymes and HIF-1α transcription factors have been reported. Thus, further insight into hypoxia-induced epigenetic alterations in EC may allow the identification of novel therapeutic targets and predictive biomarkers, impacting on patient survival and quality of life.

Dynamic regulation of epigenetic demethylation by oxygen availability and cellular redox

The chromatin structure of the mammalian genome must facilitate both precisely-controlled DNA replication together with tightly-regulated gene transcription. This necessarily involves complex mechanisms and processes which remain poorly understood. It has long been recognised that the epigenetic landscape becomes established during embryonic development and acts to specify and determine cell fate. In addition, the chromatin structure is highly dynamic and allows for both cellular reprogramming and homeostatic modulation of cell function. In this respect, the functions of epigenetic "erasers", which act to remove covalently-linked epigenetic modifications from DNA and histones are critical. The enzymatic activities of the TET and JmjC protein families have been identified as demethylases which act to remove methyl groups from DNA and histones, respectively. Further, they are characterised as members of the Fe(II)- and 2-oxoglutarate-dependent dioxygenase superfamily. This provides the intriguing possibility that their enzymatic activities may be modulated by cellular metabolism, oxygen availability and redox-based mechanisms, all of which are likely to display dynamic cell- and tissue-specific patterns of flux. Here we discuss the current evidence for such [O₂]- and redox-dependent regulation of the TET and Jmjc demethylases and the potential physiological and pathophysiological functional consequences of such regulation.

Metformin sensitizes endometrial cancer cells to chemotherapy through IDH1-induced Nrf2 expression via an epigenetic mechanism

Chemoresistance is the major obstacle to cure endometrial cancer, whereas metformin has demonstrated sensitization to chemotherapy in endometrial cancer. A novel finding states that isocitrate dehydrogenase 1 (IDH1) involves in cancer chemoresistance. Recent studies have revealed that epigenetic modifications facilitate chemoresistance. However, whether IDH1 play a role in metformin-induced endometrial cancer chemosensitivity through epigenetic modification is incompletely understood. Immunohistochemistry and Elisa assays were used to evaluate the expression pattern of IDH1 in endometrial tissue and serum, respectively. Western blot was performed to determine changes in expression of key molecules in the IDH1-ɑ-KG-TET1-Nrf2 signaling pathway after various treatments. Dot blot assays were used to assess global hydroxymethylation levels after metformin administration or plasmid transfection. Antioxidant response element (ARE) activity in the IDH1 promoter region was monitored by luciferase assay. Cancer cell sensitivity to chemotherapy was detected by SRB assay. We found that activation of the IDH1 signaling pathway in endometrial cancer tissue resulting from aberrant expression of IDH1 and its downstream mediators conferred chemoresistance. We found that this effect was abated by metformin treatment. Dot blot and HMeDIP assays revealed that metformin blocked IDH1-ɑ-KG-TET1-mediated enhancement of Nrf2 hydroxymethylation levels, eliminating chemoresistance. Moreover, we observed that chemoresistance was enhanced via a regulatory loop in which Nrf2 activated IDH1-ɑ-KG-TET1-Nrf2 signaling via binding to the ARE sites in the IDH1 promoter region. Our findings highlight a critical role of IDH1-ɑ-KG-TET1-Nrf2 signaling in chemoresistance and suggest that rational combination therapy with metformin and chemotherapeutics has the potential to suppress chemoresistance.

WISP-3 inhibition of miR-452 promotes VEGF-A expression in chondrosarcoma cells and induces endothelial progenitor cells angiogenesis

Chondrosarcoma is the second most prevalent general primary tumor of bone following osteosarcoma. Chondrosarcoma development may be linked to angiogenesis, which is principally elicited by vascular endothelial growth factor-A (VEGF-A). VEGF-A level has been recognized as a prognostic marker in angiogenesis. WNT1-inducible signaling pathway protein-3 (WISP)-3/CCN6 belongs to the CCN family and is involved in regulating several cellular functions, including cell proliferation, differentiation, and migration. Nevertheless, the effect of WISP-3 on VEGF-A production and angiogenesis in human chondrosarcoma remains largely unknown. This current study shows that WISP-3 promoted VEGF-A production and induced angiogenesis of human endothelial progenitor cells. Moreover, WISP-3-enhanced VEGF-A expression and angiogenesis involved the c-Src and p38 signaling pathways, while miR-452 expression was negatively affected by WISP-3 via the c-Src and p38 pathways. Our results illustrate the clinical significance of WISP-3, VEGF-A and miR-452 in human chondrosarcoma patients. WISP-3 may illustrate a novel therapeutic target in the metastasis and angiogenesis of chondrosarcoma.

Association between oral corticosteroid use and pyogenic liver abscesses in a case-control study

BACKGROUND AND AIM

There are no epidemiological studies focusing on the association between oral corticosteroid use and pyogenic liver abscesses. The aim of the study was to assess whether oral corticosteroid use is associated with increased odds of pyogenic liver abscesses in adults in Taiwan.

METHODS

This retrospective population-based case-control study was conducted to analyze the database of the Taiwan National Health Insurance Program from 2000 to 2013. Subjects aged 20 to 84 years with their first episode of pyogenic liver abscesses were assigned as the cases (n = 881). Randomly selected subjects without pyogenic liver abscesses aged 20 to 84 years were selected as the controls (n = 3207). A multivariable logistic regression model was used to assess the odds ratio and 95% confidence interval for the correlation of oral corticosteroid use with pyogenic liver abscesses.

RESULTS

After regulating for confounders, the adjusted odds ratio of pyogenic liver abscesses was 1.40 for subjects currently using oral corticosteroids (95% confidence interval 1.14, 1.70), compared with subjects who never used them. Upon further analysis, the adjusted odds ratio of pyogenic liver abscesses was 1.03 for subjects with current use of oral corticosteroids when increasing dosage for every one mg (95% CI 1.01, 1.06).

CONCLUSION

Although the findings are not unexpected, they are important because they suggest that current use of oral corticosteroids is significantly associated with increased odds of developing pyogenic liver abscesses in adults in Taiwan, with a dose-dependent effect.

Basic fibroblast growth factor promotes VEGF-C-dependent lymphangiogenesis via inhibition of miR-381 in human chondrosarcoma cells

A chondrosarcoma is a common, primary malignant bone tumor that can grow to destroy the bone, produce fractures and develop soft tissue masses. Left untreated, chondrosarcomas metastasize through the vascular system to the lungs and ultimately lead to large metastatic deposits of the malignant cartilage taking over lung volume and function. Vascular endothelial growth factor (VEGF)-C has been implicated in tumor-induced lymphangiogenesis and elevated expression of VEGF-C has been found to correlate with cancer metastasis. bFGF (basic fibroblast growth factor), a secreted cytokine, regulates biological activity, including angiogenesis and metastasis. We have previously reported on the important role of bFGF in angiogenesis in chondrosarcomas. However, the effect of bFGF in VEGF-C regulation and lymphangiogenesis in chondrosarcomas is poorly understood. In this investigation, we demonstrate a correlation exists between bFGF and VEGF-C in tissue specimens from patients with chondrosarcomas. To examine the lymphangiogenic effect of bFGF, we used human lymphatic endothelial cells (LECs) to mimic lymphatic vessel formation. We found that bFGF-treated chondrosarcomas promoted LEC tube formation and cell migration. In addition, bFGF knockdown inhibited lymphangiogenesis in vitro and in vivo. We also found that bFGF-induced VEGF-C is mediated by the platelet-derived growth factor receptor (PDGFR) and c-Src signaling pathway. Furthermore, bFGF inhibited microRNA-381 expression via the PDGFR and c-Src cascade. Our study is the first to describe the mechanism of bFGF-promoted lymphangiogenesis by upregulating VEGF-C expression in chondrosarcomas. Thus, bFGF could serve as a therapeutic target in chondrosarcoma metastasis and lymphangiogenesis.

Endothelin-1 promotes epithelial-mesenchymal transition in human chondrosarcoma cells by repressing miR-300

Chondrosarcoma is a malignant tumor of mesenchymal origin predominantly composed of cartilage-producing cells. This type of bone cancer is extremely resistant to radiotherapy and chemotherapy. Surgical resection is the primary treatment, but is often difficult and not always practical for metastatic disease, so more effective treatments are needed. In particular, it would be helpful to identify molecular markers as targets for therapeutic intervention. Endothelin-1 (ET-1), a potent vasoconstrictor, has been shown to enhance chondrosarcoma angiogenesis and metastasis. We report that ET-1 promotes epithelial–mesenchymal transition (EMT) in human chondrosarcoma cells. EMT is a key pathological event in cancer progression, during which epithelial cells lose their junctions and apical-basal polarity and adopt an invasive phenotype. Our study verifies that ET-1 induces the EMT phenotype in chondrosarcoma cells via the AMP-activated protein kinase (AMPK) pathway. In addition, we show that ET-1 increases EMT by repressing miR-300, which plays an important role in EMT-enhanced tumor metastasis. We also show that miR-300 directly targets Twist, which in turn results in a negative regulation of EMT. We found a highly positive correlation between ET-1 and Twist expression levels as well as tumor stage in chondrosarcoma patient specimens. Therefore, ET-1 may represent a potential novel molecular therapeutic target in chondrosarcoma metastasis.

Selective inhibition of CTCF binding by iAs directs TET-mediated reprogramming of 5-hydroxymethylation patterns in iAs-transformed cells

Methylation at cytosine (5mC) is a fundamental epigenetic DNA modification recently associated with iAs-mediated carcinogenesis. In contrast, the role of 5-hydroxymethylcytosine (5hmC), the oxidation product of 5mC in iAs-mediated carcinogenesis is unknown. Here we assess the hydroxymethylome in iAs-transformed cells, showing that dynamic modulation of hydroxymethylated DNA is associated with specific transcriptional networks. Moreover, this pathologic iAs-mediated carcinogenesis is characterized by a shift toward a higher hydroxymethylation pattern genome-wide. At specific promoters, hydroxymethylation correlated with increased gene expression. Furthermore, this increase in hydroxymethylation occurs concurrently with an upregulation of ten-eleven translocation (TET) enzymes that oxidize 5-methylcytosine (5mC) in DNA. To gain an understanding into how iAs might impact TET expression, we found that iAs inhibits the binding of CTCF at the proximal, weak CTCF binding sites of the TET1 and TET2 gene promoters and enhances CTCF binding at the stronger distal binding site. Further analyses suggest that this distal site acts as an enhancer, thus high CTCF occupancy at the enhancer region of TET1 and TET2 possibly drives their high expression in iAs-transformed cells. These results have major implications in understanding the impact of differential CTCF binding, genome architecture and its consequences in iAs-mediated pathogenesis.

Case-Control Study Examining the Association between Selective Serotonin Reuptake Inhibitors Use and Hepatocellular Carcinoma

Objectives: The purpose of the study was to assess the relationship between selective serotonin reuptake inhibitors use and hepatocellular carcinoma in Taiwan.

Methods: Using the database of the Taiwan National Health Insurance Program, we conducted a case-control study to identify 4901 subjects aged 20 years and more with newly diagnosed hepatocellular carcinoma in 2000–2013 as the cases. We randomly selected 19604 subjects aged 20 years and more without hepatocellular carcinoma as the controls. Both cases and controls were matched with sex and age. Ever use of selective serotonin reuptake inhibitors was defined as a subject who had at least a prescription for selective serotonin reuptake inhibitors before index date. Never use was defined as a subject who never had a prescription for selective serotonin reuptake inhibitors before index date. The odds ratio (OR) and 95% confidence interval (CI) for hepatocellular carcinoma associated with selective serotonin reuptake inhibitors use was estimated by the multivariable logistic regression model.

Results: Among subjects with any one of the comorbid conditions associated with hepatocellular carcinoma, the adjusted OR of hepatocellular carcinoma was 0.89 (95% CI 0.75, 1.06) for subjects with ever use of selective serotonin reuptake inhibitors, comparing with never use.

Conclusion: The findings indicate that among subjects with any one of the comorbid conditions associated with hepatocellular carcinoma, no significant association can be detected between selective serotonin reuptake inhibitors use and hepatocellular carcinoma.

Dipeptidyl Peptidase-4 Inhibitors Use and Relative Risk of Ischemic Cerebrovascular Disease in Type 2 Diabetic Patients in a Case-Control Study

Background and Objectives: Limited research focuses on the risk of ischemic cerebrovascular disease associated with use of dipeptidyl peptidase-4 inhibitors (DPP-4 inhibitors) in patients with type 2 diabetes mellitus in Taiwan. This study aimed to investigate the association between DPP-4 inhibitors use and the first episode of ischemic cerebrovascular disease. Methods: We designed a case-control study using the database of the Taiwan National Health Insurance Program. There were 1999 type 2 diabetic subjects aged 20-84 years with the first episode of ischemic cerebrovascular disease from 2000 to 2013 as the cases, and 7996 sex- and age-matched, randomly selected type 2 diabetic subjects aged 20-84 years without any type of cerebrovascular diseases as the matched controls. We estimated the odds ratio (OR) and 95% confidence interval (CI) of ischemic cerebrovascular disease associated with cumulative duration of DPP-4 inhibitors use by the multivariable logistic regression model. Results: After adjustment for confounding variables, the adjusted OR of ischemic cerebrovascular disease was 0.96 (95% CI 0.95, 0.97) in subjects with ever use of DPP-4 inhibitors as increase in use duration for every 1 month, compared with never use. The sub-analysis disclosed that the adjusted ORs of ischemic cerebrovascular disease were 1.57 (95% CI 1.36, 1.80) for subjects with cumulative duration of DPP-4 inhibitors use <1 year, and 0.70 (95% CI 0.57, 0.87) for subjects with cumulative duration of DPP-4 inhibitors use ≥1 year, compared with never use. Conclusion: Our findings suggest that DPP-4 inhibitors use correlates with relative risk reduction of the first episode of ischemic cerebrovascular disease in type 2 diabetic patients in a duration-dependent response. The beneficial effect will be marked when DPP-4 inhibitors use is ≥1 year.

Tamoxifen Use Correlates with Increased Risk of the First Episode of Ischemic Cerebrovascular Disease in Older Women with Breast Cancer: A Case-Control Study in Taiwan

Background and Objectives: There are inconsistent results about the association between ischemic cerebrovascular disease and tamoxifen use in women with breast cancer. The study aimed to evaluate the association between the risk of ischemic cerebrovascular disease and tamoxifen use in older women with breast cancer in Taiwan.

Methods: We designed a retrospective, nationwide, case-control study using the database of the Taiwan National Health Insurance Program. A total of 800 female subjects with breast cancer aged ≥65 years with the first episode of ischemic cerebrovascular disease from 2000 to 2011 were identified as the cases. Additionally, 2,876 female subjects with breast cancer aged ≥65 years without any type of cerebrovascular diseases were selected as the control subjects. The cases and the control subjects were matched with age and comorbidities. Ever use of tamoxifen was defined as a subject who had at least a prescription for tamoxifen before the index date. Never use of tamoxifen was defined as a subject who never had a prescription for tamoxifen before the index date. We used the multivariable logistic regression model to calculate the odds ratio (OR) and 95% confidence interval (CI) for ischemic cerebrovascular disease associated with tamoxifen use.

Results: After adjusting for confounding variables, the adjusted OR of ischemic cerebrovascular disease was 2.5 for subjects with ever use of tamoxifen (95% CI 2.10, 2.97), compared with never use of tamoxifen. In addition, the adjusted OR of ischemic cerebrovascular disease was 1.15 (95% CI 1.10, 1.21) in subjects with ever use of tamoxifen as increase in use duration per 1 year. The adjusted OR of ischemic cerebrovascular disease was 2.54 (95% CI 2.03, 3.17) in subjects with ever use of tamoxifen as increase in dosage per 1 mg.

Conclusions: Tamoxifen use is significantly associated with 2.5-fold increased odds of ischemic cerebrovascular disease among older women with breast cancer in Taiwan. There are duration-dependent and dose-dependent effects of tamoxifen use on the risk of ischemic cerebrovascular disease.

Tamoxifen usage correlates with increased risk of Parkinson's disease in older women with breast cancer: a case-control study in Taiwan

BACKGROUND AND OBJECTIVES

Little is known about the association between tamoxifen usage and risk of Parkinson's disease in women with breast cancer. The present study aimed to evaluate the association between tamoxifen usage and Parkinson's disease in older women with breast cancer in Taiwan.

METHODS

We conducted a retrospective nationwide case-control study using the database of the Taiwan National Health Insurance Program. In total, 293 female subjects with breast cancer, aged 65 years and above, who were newly diagnosed with Parkinson's disease between 2000 and 2011 were included. Additionally, 1053 female subjects with breast cancer aged 65 years and above without Parkinson's disease were randomly selected as controls. Both cases and controls were matched for age and comorbidities. Ever use of tamoxifen was defined as subjects who had at least a prescription for tamoxifen before the index date, whereas never use of tamoxifen was defined as those who never had a prescription for tamoxifen before the index date. We used the unconditional logistic regression model to calculate the odds ratio (OR) and 95% confidence interval (CI) for the association between tamoxifen usage and risk of Parkinson's disease.

RESULTS

After adjusting for confounding variables, the adjusted OR of Parkinson's disease was 3.32 for subjects with ever use of tamoxifen (95% CI, 2.50-4.43), compared with nonusers. Further analysis showed that the adjusted ORs of Parkinson's disease were 3.21 (95% CI, 2.29-4.49), 3.95 (95% CI, 2.77-5.64), and 11.4 (95% CI, 2.63-49.7) for subjects with < 2, 2-6, and ≥ 6 years of cumulative tamoxifen usage, respectively, when compared with nonusers.

CONCLUSIONS

Tamoxifen usage was associated with a 3.32-fold increase in the likelihood of having Parkinson's disease among older women with breast cancer in Taiwan.

Predialysis chronic kidney disease correlates with increased risk of pyogenic liver abscess: a population-based cohort study

BACKGROUND/OBJECTIVE

The incidence of pyogenic liver abscess in Taiwan appears to be much higher than that in western countries. However, little is known about the incidence of pyogenic liver abscess among patients with predialysis chronic kidney disease. The objective of this study was to assess the association between predialysis chronic kidney disease and the risk of pyogenic liver abscess in Taiwan.

METHODS

This population-based, retrospective, cohort study was conducted to analyse the database of the Taiwan National Health Insurance Program. There were 81118 subjects aged 20-84 years with newly diagnosed chronic kidney disease as the predialysis chronic kidney disease group since 2000-2010, and 81118 randomly selected subjects without chronic kidney disease as the nonchronic kidney disease group. The predialysis chronic kidney disease group and the nonchronic kidney disease group were matched with sex, age and comorbidities. The incidence of pyogenic liver abscess at the end of 2013 was calculated in both groups. Subjects who currently received dialysis therapy before the endpoint were excluded from the study. The multivariable Cox proportional hazards regression model was used to assess the hazard ratio (HR) and 95% confidence interval (CI) for the risk of pyogenic liver abscess associated with predialysis chronic kidney disease and other comorbidities including alcohol-related disease, biliary stone, chronic liver disease and diabetes mellitus.

RESULTS

The overall incidence of pyogenic liver abscess was 1·65-fold higher in the predialysis chronic kidney disease group than that in the nonchronic kidney disease group (1·38 vs. 0·83 per 1000 person-years, 95% CI 1·59, 1·71). After adjustment for covariables, the adjusted HR of pyogenic liver abscess was 1·51(95% CI 1·30, 1·76) for the predialysis chronic kidney disease group, comparing with the nonchronic kidney disease group. In addition, the adjusted HR would increase to 3·31 (95% CI 2·61, 4·19) for subjects with predialysis chronic kidney disease and with any comorbidity studied.

CONCLUSION

Predialysis chronic kidney disease is associated with 1·5-fold increased risk of pyogenic liver abscess. There seem to be a synergistic effect on the risk of pyogenic liver abscess between predialysis chronic kidney disease and comorbidities.

Use of Oral Corticosteroids and Risk of Hip Fracture in the Elderly in a Case-Control Study

Aim: Little is known regarding the relationship between use of oral corticosteroids and hip fracture in the elderly in Taiwan. The aim of the study was to examine this issue.

Methods: A retrospective population-based case-control study using the database of the Taiwan National Health Insurance Program (2000–2013) was conducted. We identified 4538 individuals aged ≥ 65 years with newly diagnosed hip fracture as the cases. We randomly selected 4538 individuals without hip fracture as the control subjects. The cases and the control subjects were matched with sex, age, comorbidities, and the year of index date. Individuals who never had a prescription for oral corticosteroids were defined as never use. Individuals who ever had at least one prescription for oral corticosteroids were defined as ever use. The odds ratio (OR) and 95% confidence interval (CI) of hip fracture associated with oral corticosteroids use was estimated by a multivariable unconditional logistic regression analysis.

Results: After adjustments for potential confounding factors, the multivariable logistic regression model showed that the adjusted OR of hip fracture was 1.17 for individuals with ever use of oral corticosteroids (95%CI 1.08, 1.28), compared to those with never use of oral corticosteroids. An sub-analysis showed that for every 1-mg increase in cumulative dose of oral corticosteroids, the adjusted OR of hip fracture was 1.01 (95% CI 1.01, 1.02). The adjusted ORs were 1.31 (95% CI 1.17, 1.47) for cumulative exposure to oral corticosteroids ≥ 3 months and 1.09 (95% CI 0.98, 1.20) for cumulative exposure < 3 months.

Conclusion: We conclude that oral corticosteroids use is associated with a trivial but statistically significant increase in risk of hip fracture in Taiwan. Additionally, the results suggest that there are dose-response and duration-response effects of oral corticosteroids on the risk of hip fracture. The results confirm our understanding of oral corticosteroid-associated hip fracture in the elderly.

3,6-Dihydroxyflavone regulates microRNA-34a through DNA methylation

BACKGROUND

Breast cancer is the common cancer in China. In previous study, we determined that 3,6-dihydroxyflavone (3,6-DHF) increases miR-34a significantly in breast carcinogenesis, but the mechanism remains unclear.

METHODS

We used qRT-PCR to analyze miR-34a and ten-eleven translocation (TET)1, TET2, TET3 levels in breast cancer cells. With a cellular breast carcinogenesis model and an experimental model of carcinogenesis in rats, TET1 levels were evaluated by western blot analysis and immunofluorescence. TET1 and 5hmC (5-hydroxymethylcytosine) levels were evaluated by immunofluorescence in nude mouse xenografts of MDA-MB-231 cells. Chromatin immunoprecipitation(ChIP) assayed for TET1 on the TET1 promoter, and dot blot analysis of DNA 5hmC was performed in MDA-MB-231 cells. We evaluated the mechanism of 3,6-DHF on the expression of tumor suppressor miR-34a by transfecting them with DNA methyltransferase (DNMT)1 plasmid and TET1 siRNA in breast cancer cells. Methylation-specific PCR detected methylation of the miR-34a promoter.

RESULTS

First, we found that 3,6-DHF promotes the expression of TET1 during carcinogen-induced breast carcinogenesis in MCF10A cells and in rats. 3,6-DHF also increased TET1 and 5hmC levels in MDA-MB-231 cells. Further study indicated that TET1 siRNA and pcDNA3/Myc-DNMT1 inhibited the 3,6-DHF reactivation effect on expression of miR-34a in breast cancer cells. Methylation-specific PCR assays indicated that TET1 siRNA and pcDNA3/Myc-DNMT1 inhibit the effect of 3,6-DHF on the demethylation of the miR-34a promoter.

CONCLUSIONS

Our study showed that 3,6-DHF effectively increases TET1 expression by inhibiting DNMT1 and DNA hypermethylation, and consequently up-regulates miR-34a in breast carcinogenesis.

Population-based cohort study investigating the correlation of diabetes mellitus with pleural empyema in adults in Taiwan

We assessed the association between diabetes mellitus and the risk of pleural empyema in Taiwan.A population-based retrospective cohort study was conducted using the database of the Taiwan National Health Insurance Program. There were 28,802 subjects aged 20 to 84 years who were newly diagnosed with diabetes mellitus from 2000 to 2010 as the diabetes group and 114,916 randomly selected subjects without diabetes mellitus as the non-diabetes group. The diabetes group and the non-diabetes group were matched by sex, age, comorbidities, and the year of index date. The incidence of pleural empyema at the end of 2011 was estimated. A multivariable Cox proportional hazards regression model was used to estimate the hazard ratio (HR) and 95% confidence interval (95% CI) for pleural empyema associated with diabetes mellitus.The overall incidence of pleural empyema was 1.65-fold higher in the diabetes group than that in the non-diabetes group (1.58 vs 0.96 per 10,000 person-years, 95% CI 1.57-1.72). After adjusting for confounders, a multivariable Cox proportional hazards regression model revealed that the adjusted HR of pleural empyema was 1.71 in subjects with diabetes mellitus (95% CI 1.16-2.51), compared with those without diabetes mellitus. In further analysis, even in the absence of any comorbidity, the adjusted HR was 1.99 for subjects with diabetes mellitus alone (95% CI 1.18-3.38).Diabetic patients confer a 1.71-fold increased hazard of developing pleural empyema. Even in the absence of any comorbidity, the risk remains existent.

Association of use of selective serotonin reuptake inhibitors with risk of acute pancreatitis: a case-control study in Taiwan

BACKGROUND AND OBJECTIVES

Few studies have reported the association of the use of selective serotonin reuptake inhibitors (SSRIs) with acute pancreatitis. We conducted a population-based case-control study to explore this relationship.

METHODS

In this study, 4631 cases with first attack of acute pancreatitis and 4631 controls without acute pancreatitis were selected using a randomly sampled cohort of one million health insurance enrollees from 2000 to 2013. Both cases and controls were aged 20-84 years and were matched with sex, age, comorbidities, and index year of diagnosis of acute pancreatitis. Patients with current use of SSRIs were defined as those whose last tablet of SSRIs was noted ≤ 7 days before the date of diagnosis of acute pancreatitis; patients with late use of SSRIs were defined as those whose last tablet of SSRIs was noted ≥ 8 days before the date of diagnosis; and patients with no use of SSRIs were defined as those who were never prescribed SSRIs. The odds ratio (OR) and 95% confidence interval (CI) for acute pancreatitis associated with the use of SSRIs were assessed using multivariate unconditional logistic regression analysis.

RESULTS

After adjusting for covariables, multivariate logistic regression analysis revealed that compared with patients with no use of SSRIs, the adjusted OR of acute pancreatitis for those with current use of SSRIs was 1.7 (95% CI, 1.1-2.5), whereas that for patients with late use of SSRIs was 1.0 (95% CI, 0.9-1.2) without statistical significance.

CONCLUSIONS

Current use of SSRIs is associated with the diagnosis of acute pancreatitis. Therefore, clinicians should consider the possibility of SSRI-associated acute pancreatitis among patients currently taking SSRIs and those presenting with the diagnosis of acute pancreatitis without a definite cause.

Cell-line dependent effects of hypoxia prior to irradiation in squamous cell carcinoma lines

Purpose

To assess the impact of hypoxia exposure on cellular radiation sensitivity and survival of tumor cells with diverse intrinsic radiation sensitivity under normoxic conditions.

Materials and methods

Three squamous cell carcinoma (SCC) cell lines, with pronounced differences in radiation sensitivity, were exposed to hypoxia prior, during or post irradiation. Cells were seeded in parallel for colony formation assay (CFA) and stained for γH2AX foci or processed for western blot analysis.

Results

Hypoxia during irradiation led to increased cellular survival and reduced amount of residual γH2AX foci in all the cell lines with similar oxygen enhancement ratios (OER SKX: 2.31, FaDu: 2.44, UT-SCC5: 2.32), while post-irradiation hypoxia did not alter CFA nor residual γH2AX foci. Interestingly, prolonged exposure to hypoxia prior to irradiation resulted in differential outcome, assessed as Hypoxia modifying factor (HMF) namely radiosensitization (SKX HMF: 0.76), radioresistance (FaDu HMF: 1.54) and no effect (UT SCC-5 HMF: 1.1). Notably, radiosensitization was observed in the ATM-deficient SKX cell line while UT SCC-5 and to a lesser extent also FaDu cells showed radiation- and hypoxia-induced upregulation of ATM phosphorylation. Across all the cell lines Rad51 was downregulated whereas phosphor-DNA-PKcs was enhanced under hypoxia for FaDu and UTSCC-5 and was delayed in the SKX cell line.

Conclusion

We herein report a key role of ATM in the cellular fitness of cells exposed to prolonged moderate hypoxia prior to irradiation. While DNA damage response post-irradiation seem to be mainly driven by non-homologous end joining repair pathway in these conditions, our data suggest an important role for ATM kinase in hypoxia-driven modification of radiation response.

Novel Epigenetic Controlling of Hypoxia Pathway Related to Overexpression and Promoter Hypomethylation of TET1 and TET2 in RPE Cells

CpG methylation of DNA takes part in a specific epigenetic memory that plays crucial roles in the differentiation and abnormality of the cells. The methylation pattern aberration of genomes is affected in three ways, namely DNA methyltransferase (DNMT), ten-eleven translocation (TET), and methyl-binding domain (MBD) proteins. Of these, TET enzymes have recently been demonstrated to be master modifier enzymes in the DNA methylation process. Additionally, recent studies emphasize that not only epigenetic phenomena play a role in controlling hypoxia pathway, but the hypoxia condition also triggers hypomethylation of genomes that may help with the expression of hypoxia pathway genes. In this study, we suggested that TET1 and TET2 could play a role in the demethylation of genomes under chemical hypoxia conditions. Herein, the evaluating methylation status and mRNA expression of mentioned genes were utilized through real-time PCR and methylation-specific PCR (MSP), respectively. Our results showed that TET1 and TET2 genes were overexpressed (P < 0.05) under chemical hypoxia conditions in Retinal Pigment Epithelial (RPE) cells, whereas the promoter methylation status of them were hypomethylated in the same condition. Therefore, chemical hypoxia not only causes overexpression of TET1 and TET2 but also could gradually do promoter demethylation of same genes. This is the first study to show the relationship between epigenetics and the expression of mentioned genes related to hypoxia pathways. Furthermore, it seems that these associations in RPE cells are subjected to chemical hypoxia as a mechanism that could play a crucial role in methylation pattern changes of hypoxia-related diseases such as cancer and ischemia. J. Cell. Biochem. 118: 3193-3204, 2017. © 2017 Wiley Periodicals, Inc.

Promising therapeutic role of miR-27b in tumor

MicroRNAs are small nonprotein-encoding RNAs ranging from 18 to 25 nucleotides in size and regulate multiple biological pathways via directly targeting a variety of associated genes in cancers. MicroRNA-27b is a highly conserved MicroRNA throughout vertebrates and there are two homologs (hsa-miR-27a and hsa-miR-27b) in humans. MicroRNA-27b is an intragenic microRNA located on chromosome 9q22.1 within the C9orf3 gene, clustering with miR-23b and miR-24-1 in human. As a frequently dysregulated microRNA in human cancers, microRNA-27b could function as a tumor suppressor or an oncogenic microRNA. More and more studies indicate that microRNA-27b is involved in affecting various biological processes, such as angiogenesis, proliferation, metastasis, and drug resistance, and thus may act as a promising therapeutic target in human cancers. In this review, we discuss the role of microRNA-27b in detail and offer novel insights into molecular targeting therapy for cancers.

G9A performs important roles in the progression of breast cancer through upregulating its targets

Breast cancer (BC) is the most common type of malignancy in females worldwide, however, its underlying mechanisms remain poorly understood. The present study aimed to investigate the mechanisms behind the development and progression of BC and identify potential biomarkers for it. The chromatin immunoprecipitation-DNA sequencing (ChIP-Seq) dataset GSM1642516 and gene expression dataset GSE34925 were downloaded from the Gene Expression Omnibus database. Affy and oligo packages were used for the background correction and normalization of the gene expression dataset. Based on Limma package and the criteria of a fold change >1.41 or <0.71, and a false discovery rate adjusted P-value <0.05, differentially-expressed genes (DEGs) in euchromatic histone lysine methyltransferase 2 (G9A) -knockout (KO) breast samples compared with control samples were identified. The Database for Annotation, Visualization and Integrated Analysis was used for the functional enrichment analysis of the DEGs. Bowtie 2 and model-based analysis of ChIP-Seq version 14 (macs14) were used for the mapping of raw reads and the identification of G9A binding sites (peaks), respectively. In addition, overlapping genes between the DEGs and genes in the peaks located in −3000 to 3000 bp centered in the transcription start sites (conpeaks) were screened out and microRNAs (miRNAs) believed to regulate those overlaps were identified through the TargetScan database. A total of 217 DEGs were identified in G9A-KO samples, which were mainly involved in the biological processes and pathways associated with the inflammatory response and cancer progression. A total of 10,422 peaks, containing 1,210 conpeaks involving 1,138 genes, were identified. Among the 1,138 genes, 15 were overlapped with the DEGs, and 35 miRNAs were identified to regulate those overlaps. Insulin-induced gene 1 was regulated by 9 genes in the miRNA-gene regulation network, which may indicate its importance in the progression of BC. The present study identified potential biomarkers of BC that may be useful in the diagnosis and treatment of patients with the disease.

Increased TET1 Expression in Inflammatory Microenvironment of Hyperinsulinemia Enhances the Response of Endometrial Cancer to Estrogen by Epigenetic Modulation of GPER

Background: Insulin resistance (IR) has been well studied in the initiation and development of endometrial endometrioid carcinoma (EEC). As yet, it has been largely neglected for estrogen sensitivity in local endometrium in hyperinsulinemia-induced systemic microenvironment. The aim of this study was to investigate the role of insulin in regulating estrogen sensitivity and explore the potential mechanisms in insulin-driven inflammatory microenvironment.

Methods: We first investigated the effect of insulin on estradiol-driven endometrial cancer cells proliferation in vitro to address the roles of insulin in modulating estrogen sensitivity. Then GPER, ERα and TET1 in EEC samples with or without insulin resistance were screened by immunohistochemistry to confirm whether insulin resistance regulates estrogen receptors. Further mechanism analysis was carried out to address whether TET1 was mediated epigenetic modulation of GPER in insulin-induced microenvironment.

Results: Insulin enhanced estradiol-driven endometrial cancer cells proliferation by up-regulating G-protein-coupled estrogen receptor (GPER) expression, but not ERα or ERβ. Immunohistochemistry of EEC tissues showed that GPER expression was greatly increased in endometrial tissues from EEC subjects with insulin resistance and was positively correlated with Ten-eleven-translocation 1 (TET1) expression. Mechanistically, insulin up-regulates TET1 expression, and the latter, an important DNA hydroxymethylase, could up-regulate GPER expression through epigenetic modulation.

Conclusion: This study identified TET1 as the upstream regulator of GPER expression and provides a possible mechanism that insulin-induced positive regulation of estrogen sensitivity in endometrial cancer cells. Increasing expression of GPER through TET1-mediated epigenetic modulation may emerge as the main regulator to enhance the response of endometrial cancer to estrogen in insulin-driven inflammatory microenvironment.

Association of TET1 expression with colorectal cancer progression

OBJECTIVE

The ten-eleven translocation (TET) proteins, as methylcytosine dioxygenases, catalyze 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC). The altered expression of TET1 disrupts the balance between DNA methylation and demethylation. This alteration has been reported to be associated with carcinogenesis in various malignancies. The aim of the present study was to investigate changes in expression and the role of TET1 in colorectal cancer (CRC).

MATERIAL AND METHODS

A total of 109 CRC patients who underwent radical surgical colon resection were enrolled. The QuantiGene Plex Assay was used to detect the expression of TET1 in CRC tissues and matching adjacent normal tissues. We analyzed the associations between TET1 expression levels and various clinicopathologic features of CRC. TET1 overexpression and depletion cells were constructed to investigate its biological role in CRC.

RESULTS

Compared to normal tissues, the expression level of TET1 in CRC was significantly lower. The ratio of TET1 in CRC tissues to that in adjacent normal tissues (C/N-TET1) was an independent overall survival predictive factor. Moreover, in vitro studies showed that TET1 could inhibit cell growth and promote cell metastasis and invasion.

CONCLUSIONS

These findings indicated that TET1 played a multifaceted role in the pathogenesis of CRC, and thereby resulting in multiple effects on tumor progression.

TET1 promotes cisplatin-resistance via demethylating the vimentin promoter in ovarian cancer

The development of chemo-resistance impairs the outcome of the first line platinum-based chemotherapies for ovarian cancer. Deregulation of DNA methylation/demethylation provides a critical mechanism for the occurrence of chemo-resistance. The ten-eleven translocation (TET) family of dioxygenases including TET1/2/3 plays an important part in DNA demethylation, but their roles in cisplatin resistance have not been elucidated. Using cisplatin-sensitive and cisplatin-resistant ovarian cancer cell models, we found that TET1 was significantly upregulated in cisplatin-resistant CP70 cells compared with that in cisplatin-sensitive A2780 cells. Ectopic expression of TET1 in A2780 cells promoted cisplatin resistance and decreased cytotoxicity induced by cisplatin, while inhibition of TET1 by siRNA transfection in CP70 cells attenuated cisplatin resistance and enhanced cytotoxicity of cisplatin. Increased TET1 induced re-expression of vimentin through active DNA demethylation, and cause partial epithelial-to-mesenchymal (EMT) in A2780 cells. Contrarily, knocking down of TET1 in CP70 cells reduced vimentin expression and reversed EMT process. Immunohistochemical analysis of TET1 in human ovarian cancer tissues revealed that TET1 existed in nucleus and cytoplasm in ovarian cancer tissues. And the expression of nuclear TET1 was positively correlated with residual tumor and chemotherapeutic response. Thus, TET1 expression causes resistance to cisplatin and one of the targets of TET1 action is vimentin in ovarian cancer.

CTGF promotes osteosarcoma angiogenesis by regulating miR-543/angiopoietin 2 signaling

Osteosarcoma is the most common primary solid tumor of bone. It has a high metastatic potential and occurs predominantly in adolescents and young adults. Angiopoietin 2 (Angpt2) is a key regulator in tumor angiogenesis, facilitating tumor growth and metastasis. Connective tissue growth factor (CTGF, also known as CCN2), is a cysteine-rich protein that has been reported to promote metastasis of osteosarcoma. However, the effect of CTGF on Angpt2 regulation and angiogenesis in human osteosarcoma remains largely unknown. We found that overexpression of CTGF in osteosarcoma cells increased Angpt2 production and induced angiogenesis, in vitro and in vivo. Our findings demonstrate that CTGF-enhanced Angpt2 expression and angiogenesis is mediated by the phospholipase C (PLC)/protein kinase C (PKCδ) signaling pathway. Moreover, endogenous microRNA-543 (miR-543) expression was negatively regulated by CTGF via the PLC/PKCδ pathway. We also provide evidence showing clinical significance between CTGF, Angpt2, and miR-543 as well as tumor staging in human osteosarcoma tissue. CTGF may serve as a therapeutic target in the process of osteosarcoma metastasis and angiogenesis.

Increased Risk of Pulmonary Tuberculosis in Patients with Depression: A Cohort Study in Taiwan

BACKGROUND/OBJECTIVE

Tuberculosis (TB) and depression were major public health issues worldwide and the mutual causative relationships between them were not exhaustive. This study was performed to explore the association between depression, comorbidities, and the risk of pulmonary TB in Taiwan.

METHODS

The cohort study used the database of the Taiwan National Health Insurance Program. The depression group included 34,765 subjects aged 20-84 years with newly diagnosed depression from 2000 to 2012, and the non-depression group included 138,187 randomly selected subjects without depression. Both depression and non-depression groups were matched with respect to sex, age, and comorbidities. We explored the incidence of pulmonary TB at the end of 2013 in both the groups and used multivariable Cox proportional hazards regression model to explore the hazard ratio (HR) and 95% confidence interval (CI) for the risk of pulmonary TB associated with depression.

RESULTS

The overall incidence of pulmonary TB was 1.16-fold greater in the depression group than that in the non-depression group (1.52 vs. 1.31 per 1,000 person-years, 95% CI 1.12, 1.21). The multivariable Cox proportional hazards regression analysis revealed that the adjusted HR of pulmonary TB was 1.15 for the depression group (95% CI 1.03, 1.28), compared with the non-depression group.

CONCLUSION

Depression is associated with 1.15-fold increased hazard of pulmonary TB in Taiwan.

Amphiregulin enhances VEGF-A production in human chondrosarcoma cells and promotes angiogenesis by inhibiting miR-206 via FAK/c-Src/PKCδ pathway

Chondrosarcoma is the second most common primary malignancy of bone after myeloma and osteosarcoma. Chondrosarcoma development may be linked to angiogenesis, which is principally elicited by vascular endothelial growth factor-A (VEGF-A). The expression of VEGF-A has been recognized as a prognostic marker in angiogenesis. Amphiregulin (AR), an epidermal growth factor receptor ligand, promotes tumor proliferation, metastasis and angiogenesis. However, the role of AR in VEGF-A expression and angiogenesis in human chondrosarcoma remains largely unknown. This current study shows that AR promoted VEGF-A production and induced angiogenesis of human endothelial progenitor cells. Moreover, AR-enhanced VEGF-A expression and angiogenesis involved the FAK, c-Src and PKCδ signaling pathways, while miR-206 expression was negatively mediated by AR via the FAK, c-Src and PKCδ pathways. Our results illustrate the clinical significance between AR, VEGF-A and miR-206, as well as tumor stage, in human chondrosarcoma. AR may represent a novel therapeutic target in the metastasis and angiogenesis of chondrosarcoma.

The association between arterial stiffness and tongue manifestations of blood stasis in patients with type 2 diabetes

BACKGROUND

Diabetes mellitus (DM) is a hypercoagulable state and is associated with highly increased risk of vascular complications. In the theory of traditional Chinese medicine (TCM), these vascular complications are classified as blood stasis. Diagnosis of the tongue plays an important role in TCM; a bluish tongue, petechiae, and engorged sublingual collateral vessels are manifestations of blood stasis. This study aimed to characterize the tongue manifestations of blood stasis and derive a relationship between blood stasis and vascular disorders in patients with type 2 DM.

METHOD

We conducted a cross-sectional study of 140 patients with type 2 DM, and compared demography, laboratory, physical examination, ankle brachial index(ABI), brachial-ankle pulse wave velocity (ba-PWV), and tongue manifestation datas. An automatic tongue diagnosis system was used to capture tongue images and characterize clinical tongue manifestations.

RESULTS

A bluish or petechiae tongue was assoicated with a significant decrease in high-density lipoprotein level, and bluish tongue was associated with significant increase in blood triglyceride in patients with type 2 DM. On assessing arterial stiffness, patients with a petechiae tongue had a higher ba-PWV for both sides (L:1938.41 ± 469.54 cm/sec v.s.1723.99 ± 302.16, p = 0.02; R:1937.28 ± 405.55 v.s.1741.99 ± 325.82, p = 0.03).

CONCLUSION

Blood stasis, particularly a tongue with petechiae, may be associated with arterial stiffness in patients with type 2 DM. Furthermore, tongue diagnosis could detect blood stasis relevant to DM and could serve as a feasible predictor for DM.

Leptin promotes VEGF-C production and induces lymphangiogenesis by suppressing miR-27b in human chondrosarcoma cells

Chondrosarcoma is the second most frequently occurring type of bone malignancy that is characterized by the distant metastasis propensity. Vascular endothelial growth factor-C (VEGF-C) is the chief lymphangiogenic mediator, and makes crucial contributions to tumor lymphangiogenesis. Leptin is an adipocytokine and has been indicated to facilitate tumorigenesis, angiogenesis and metastasis. However, the effect of leptin on VEGF-C regulation and lymphangiogenesis in human chondrosarcoma has hugely remained a mystery. Our results showed a clinical correlation between leptin and VEGF-C as well as tumor stage in human chondrosarcoma tissues. We further demonstrated that leptin promoted VEGF-C production and secretion in human chondrosarcoma cells. The conditioned medium from leptin-treated chondrosarcoma cells induced lymphangiogenesis of human lymphatic endothelial cells. We also found that leptin-induced VEGF-C is mediated by the FAK, PI3K and Akt signaling pathway. Furthermore, the expression of microRNA-27b was negatively regulated by leptin via the FAK, PI3K and Akt cascade. Our study is the first to describe the mechanism of leptin-promoted lymphangiogenesis by upregulating VEGF-C expression in chondrosarcomas. Thus, leptin could serve as a therapeutic target in chondrosarcoma metastasis and lymphangiogenesis.

Adiponectin promotes VEGF-C-dependent lymphangiogenesis by inhibiting miR-27b through a CaMKII/AMPK/p38 signaling pathway in human chondrosarcoma cells

Chondrosarcoma is the second most frequently occurring type of bone malignancy characterized by distant metastatic propensity. Vascular endothelial growth factor-C (VEGF-C) is the major lymphangiogenic factor, and makes crucial contributions to tumour lymphangiogenesis and lymphatic metastasis. Adiponectin is a protein hormone secreted predominantly by differentiated adipocytes. In recent years, adiponectin has also been indicated as facilitating tumorigenesis, angiogenesis and metastasis. However, the effect of adiponectin on VEGF-C regulation and lymphangiogenesis in chondrosarcoma has remained largely a mystery. In the present study, we have shown a clinical correlation between adiponectin and VEGF-C, as well as tumour stage, in human chondrosarcoma tissues. We further demonstrated that adiponectin promoted VEGF-C expression and secretion in human chondrosarcoma cells. The conditioned medium from adiponectin-treated cells significantly induced tube formation and migration of human lymphatic endothelial cells. In addition, adiponectin knock down inhibited lymphangiogenesis in vitro and in vivo We also found that adiponectin-induced VEGF-C is mediated by the calmodulin-dependent protein kinase II (CaMKII), AMP-activated protein kinase (AMPK) and p38 signaling pathway. Furthermore, the expression of miR-27b was negatively regulated by adiponectin via the CaMKII, AMPK and p38 cascade. The present study is the first to describe the mechanism of adiponectin-promoted lymphangiogenesis by up-regulating VEGF-C expression in chondrosarcomas. Thus, adiponectin could serve as a therapeutic target in chondrosarcoma metastasis and lymphangiogenesis.