Context Both Graves disease (GD) and inflammatory bowel disease (IBD) are common autoimmune diseases that severely damage a patient’s quality of life. Previous epidemiological studies have suggested associations between GD and IBD. However, whether a causal relationship exists between these 2 diseases remains unknown. Objective To infer a causal relationship between GD and IBD using bidirectional 2-sample Mendelian randomization (MR). Methods We performed bidirectional 2-sample MR to infer a causal relationship between GD and IBD using genome-wide association study summary data obtained from Biobank Japan and the International Inflammatory Bowel Disease Genetic Consortium. Several methods (random-effect inverse variance weighted, weighted median, MR-Egger regression, and MR-PRESSO) were used to ensure the robustness of the causal effect. Heterogeneity was measured based on Cochran's Q value. Horizontal pleiotropy was evaluated by MR-Egger regression and leave-one-out analysis. Results Genetically predicted IBD may increase the risk of GD by 24% (odds ratio [OR] 1.24, 95% CI 1.01-1.52, P = .041). Crohn disease (CD) may increase the risk of GD, whereas ulcerative colitis (UC) may prevent patients from developing GD. Conversely, genetically predicted GD may slightly increase the risk of CD, although evidence indicating that the presence of GD increased the risk of UC or IBD was lacking. Outlier-corrected results were consistent with raw causal estimates. Conclusion Our study revealed a potentially higher comorbidity rate for GD and CD. However, UC might represent a protective factor for GD. The underlying mechanism and potential common pathways await discovery.
1 January 2017 in International Journal of Endocrinology
Background. MicroRNA (miRNA) dysregulation was commonly seen in papillary thyroid carcinoma (PTC), andmiR-195was verified to be downregulated in PTC by the large data set analysis from The Cancer Genome Atlas (TCGA). Our study aimed to explore the biological functions and the underlying molecular mechanisms ofmiR-195in PTC.Methods. The relative expression ofmiR-195and its target genes were assessed by quantitative RT-PCR assay in 38 pairs of PTC and the adjacent thyroid tissues. Assays were performed to evaluate the effect ofmiR-195on the proliferation, migration, and invasion in PTC cell lines. Moreover, we searched for targets ofmiR-195and explored the possible molecular pathway ofmiR-195in PTC.Results. We found thatmiR-195was downregulated in PTC cell lines and tissues. Overexpression ofmiR-195significantly inhibited cell proliferation, migration, and invasion in K1 and BCPAP cell lines.CCND1andFGF2, which had inverse correlations withmiR-195in clinical specimens, were found to be the direct targets ofmiR-195. Furthermore,miR-195might be involved in PTC tumorigenesis by suppressing the Wnt/β-catenin signaling pathway.Conclusions. These results highlight an important role ofmiR-195in the initiation and progression of PTC and implicate the potential application ofmiR-195in PTC target therapy.
Given the increasing prevalence of obesity, the white-to-beige adipocyte conversion has attracted interest as a target for obesity treatment. Gamma-aminobutyric acid (GABA) treatment can reduce obesity, but the underlying mechanism remains unclear. Here, we aimed to investigate the mechanism by which GABA triggers weight loss by improving the beiging of inguinal white adipose tissue (iWAT) and the role of gut microbiota in this process. The results showed that GABA reduced body weight and adipose inflammation and promoted the expression of thermogenic genes in the iWAT. The 16S rRNA sequence analysis of gut microbiota showed that GABA treatment increased the relative abundance of Bacteroidetes, Akkermansia, and Romboutsia and reduced that of Firmicutes and Erysipelatoclostridium in obese mice. Additionally, serum metabolomic analysis revealed that GABA treatment increased 3-hydroxybutyrate and reduced oxidized lipid levels in obese mice. Spearman’s correlation analysis showed that Akkermansia and Romboutsia were negatively associated with the levels of oxidized lipids. Fecal microbiota transplantation analysis confirmed that the gut microbiota was involved in the white-to-beige adipocyte reconstruction by GABA. Overall, our findings suggest that GABA treatment may promote iWAT beiging through the gut microbiota in obese mice. GABA may be utilized to protect obese people against metabolic abnormalities brought on by obesity and gut dysbiosis.
Background: BRAF mutation is one of the most common genetic alterations contributing to the initiation and progression of papillary thyroid carcinoma (PTC). However, the prognostic value of BRAF mutation for PTC is limited. Novel markers are needed to identify BRAF-mutant patients with poor prognosis.Methods: Transcriptional expression data were downloaded from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets. Pathway enrichment was performed by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and gene set enrichment analysis (GSEA). Protein-protein interaction networks were predicted by the GeneMANIA. The correlation between STRA6 expression and immune infiltration was analyzed by tumor immune estimation resource (TIMER) and tumor-immune system interaction database (TISIDB). Immunohistochemistry was used to detect the STRA6 protein expression level of PTC. Infiltration of regulatory T cells (Tregs) and CD8+ T cells in tumor samples were analyzed by fluorescent multiplex immunohistochemistry.Results: In BRAF-mutant PTC, STRA6 was extremely upregulated and predicted unfavorable survival, which was an independent risk factor for increased mortality risk. Bioinformatic analyses indicated that STRA6 might activate the MAPK pathway synergistically with BRAFV600E. The expression of STRA6 was associated with immune infiltrates and T cell exhaustion. Fluorescent multiplex immunohistochemistry showed that STRA6 increased Tregs abundance and decreased CD8+ T cells infiltration in PTC. Moreover, STRA6 promoted epithelial-mesenchymal transition via increased cancer-associated fibroblasts infiltration.Conclusions: Our study demonstrates STRA6 may serve as a prognostic marker for BRAF-mutated PTC, which may drive thyroid carcinogenesis via activation of oncogenic pathway and regulation of tumor immunosuppressive microenvironment.
Thyroid cancer is the most common endocrine malignancy, and its incidence has increased in the past decades. Selenium has been shown to have therapeutic effects against several tumors. However, its role in thyroid cancer and its underlying molecular mechanism remains to be explored. In the present study, we demonstrated that sodium selenite significantly decreased cell viability and induced G0/G1 cell cycle arrest and apoptosis in thyroid cancer cells in a dose-dependent manner. Transcriptomics revealed that sodium selenite induced intracellular reactive oxygen species (ROS) by promoting oxidative phosphorylation. Increased intracellular ROS levels inhibited the AKT/mTOR signaling pathway and upregulated EIF4EBP3. Intracellular ROS inhibition by N-acetylcysteine (NAC) ameliorated the cellular effects of sodium selenite. The in vitro findings were reproduced in xenograft thyroid tumor models. Our data demonstrated that sodium selenite exhibits strong anticancer effects against thyroid cancer cells, which involved ROS-mediated inhibition of the AKT/mTOR pathway. This suggests that sodium selenite may serve as a therapeutic option for advanced thyroid cancer.