Bladder Cancer Cells Exert Pleiotropic Effects on Human Adipose-Derived Stem Cells

Causal Association of Adipose Tissue with Bladder Cancer and the Mediating Effects of Circulating Metabolites: A Mendelian Randomization Study

Background: Previous studies have indicated that there is an association between obesity and bladder cancer (BCa). However, the relationship between fat distribution, which is more representative of the risk of obesity, and BCa remains unclear. This study aimed to investigate the causal relationship between fat distribution and BCa, and the mediating role of circulating metabolites. Methods: The necessary data were obtained from a large Genome-Wide Association Studies (GWAS) database. Two-sample and two-step Mendelian randomization (MR) analyses were performed to investigate the association between fat distribution and BCa, as well as the mediating effect of circulating metabolites. The inverse variance weighted (IVW) method was the main analysis method. Heterogeneity tests, horizontal pleiotropy analyses, Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO) tests, and leave-one-out analyses were performed to assess the stability of the results. Results: The IVW method indicated that abdominal subcutaneous adipose tissue adjusted for body mass index (BMI) and height (ASATadj) and abdominal subcutaneous/gluteofemoral adipose tissue (ASAT/GFAT) increased the risk of BCa. The odds ratio (OR) for ASATadj was 1.78 (95% CI=1.27-2.50, p=0.001) and that for ASAT/GFAT was 1.64 (95% CI=1.01-2.66, p=0.047). Furthermore, two-step MR analysis revealed that the effect of ASAT/GFAT on BCa was mediated by valine (proportion mediated: 7.13%, 95% CI = 3.57%-10.69%, p=0.045). Conclusions: Our research shows that, unlike most studies which focus on visceral fat, ASAT also impacts human health by increasing the risk of BCa, with the blood metabolite valine involved in this process. Monitoring and reducing ASAT accumulation can help reducce the disease burden of BCa.

Comprehensive Analysis of Novel Genes and Pathways Associated with Osteogenic Differentiation of Adipose Stem Cells

Background. Adipose-derived stem cells (ADSCs) are an important alternative source of mesenchymal stem cells (MSCs) and show great promise in tissue engineering and regenerative medicine applications. However, identifying the novel genes and pathways and finding the underlying mechanisms regulating ADSCs osteogenic differentiation remain urgent. Methods. We downloaded the gene expression profiles of GSE63754 and GSE37329 from the Gene Expression Omnibus (GEO) Database. We derived differentially expressed genes (DEGs) before and after ADSC osteogenic differentiation, followed by Gene Ontology (GO) functional and KEGG pathway analysis and protein-protein interaction (PPI) network analysis. 211 differentially expressed genes (142 upregulated genes and 69 downregulated genes) were aberrantly expressed. GO analysis revealed that these DEGs were associated with extracellular matrix organization, protein extracellular matrix, and semaphorin receptor binding. Conclusions. Our study provides novel genes and pathways that play important roles in regulating ADSC osteogenic differentiation, which may have potential therapeutic targets for clinic.