Butyrate prevents the migration and invasion, and aerobic glycolysis in gastric cancer via inhibiting Wnt/ß-catenin/c-Myc signaling.

Gastric cancer (GC) remains a common cause of cancer death worldwide. Evidence has found that butyrate exhibited antitumor effects on GC cells. However, the mechanism by which butyrate regulate GC cell proliferation, migration, invasion, and aerobic glycolysis remains largely unknown. The proliferation, migration, and invasion of GC cells were tested by EdU staining, transwell assays. Additionally, protein expressions were determined by western blot assay. Next, glucose uptake, lactate production, and cellular ATP levels in GC cells were detected. Furthermore, the antitumor effects of butyrate in tumor-bearing nude mice were evaluated. We found, butyrate significantly prevented GC cell proliferation, migration, and invasion (p < .01). Additionally, butyrate markedly inhibited GC cell aerobic glycolysis, as shown by the reduced expressions of GLUT1, HK2, and LDHA (p < .01). Moreover, butyrate notably decreased nuclear ß-catenin and c-Myc levels in GC cells (p < .01). Remarkably, through activating Wnt/ß-catenin signaling with LiCl, the inhibitory effects of butyrate on the growth and aerobic glycolysis of GC cells were diminished (p < .01). Moreover, butyrate notably suppressed tumor volume and weight in GC cell xenograft nude mice in vivo (p < .01). Meanwhile, butyrate obviously reduced nuclear ß-catenin, c-Myc, GLUT1, HK2 and LDHA levels in tumor tissues in GC cell xenograft mice (p < .01). Collectively, butyrate could suppress the growth and aerobic glycolysis of GC cells in vitro and in vivo via downregulating wnt/ß-catenin/c-Myc signaling. These findings are likely to prove useful in better understanding the role of butyrate in GC.

The molecular basis of the associations between non-alcoholic fatty liver disease and colorectal cancer.

Background: Given the ongoing research on non-alcoholic fatty liver disease (NAFLD) and colorectal cancer (CRC), the number of studies suggesting a strong link between NAFLD and CRC is on the rise, while its underlying pathological mechanisms remain uncertain. This study aims to explore the shared genes and mechanisms and to reveal the molecular basis of the association between CRC and NAFLD through bioinformatics approaches. Methods: The Gene Expression Omnibus (GEO) dataset GSE89632 is downloaded for NAFLD cases and healthy controls. Additionally, the GSE4107 and GSE9348 datasets are obtained for CRC cases and healthy controls. Differentially expressed genes (DEGs) are obtained for NAFLD and CRC datasets, as well as shared genes between the two disorders. GO and KEGG enrichment analyses are further conducted. Subsequently, the STRING database and Cytoscape software are utilized to establish the PPI network and identify the hub genes. Then, co-expression analysis is performed using GeneMANIA. Subsequently, ROC curves and external datasets validation were applied to further screen the candidate markers. Finally, NetworkAnalyst is available as a means to construct a miRNA-gene regulatory network. Results: Under the threshold of FDR ≤ 0.01, 147 common genes are obtained in NAFLD and CRC. Categorization of GO functions shows that DEGs are predominantly enriched in "response to organic substance", "cellular response to chemical stimulus", and "response to external stimulus". The predominant KEGG pathways in DEGs are the "IL-17 signaling pathway", the "TNF signaling pathway", "Viral protein interaction with cytokine and cytokine receptor", "Cytokine-cytokine receptor interaction", and the "Toll-like receptor signaling pathway". Additionally, MYC, IL1B, FOS, CXCL8, PTGS2, MMP9, JUN, and IL6 are identified as hub genes by the evaluation of 7 algorithms. With the construction of miRNA-gene networks, 2 miRNAs, including miR-106a-5p, and miR-204-5p are predicted to be potential key miRNAs. Conclusion: This study identifies possible hub genes acting in the co-morbidity of NAFLD and CRC and discovers the interaction of miRNAs and hub genes, providing a novel understanding of the molecular basis for the relevance of CRC and NAFLD, thus contributing to the development of new therapeutic strategies to combat NAFLD and CRC.

[Hepatitis B surface antigen affects the expression of lipid metabolism-related genes in HepG2 cells].

OBJECTIVE: To investigate the influence of hepatitis B virus (HBV)-encoded small surface protein (SHBs) on hepatic cell expression of host genes related to lipid metabolism. METHODS: The full-length SHBs gene was amplified from HBV genotype C by polymerase chain reaction (PCR) and cloned into the pcDNA3.1(+) expression vector for stable transfection into HepG2 cells (selected by G418 screening); cells transfected with empty vector served as control. The SHBs mRNA and protein levels were detected by reverse transcription-PCR and enzyme-linked immunosorbent assay. SHBs effects on expression of genes and proteins related to lipid metabolism were detected by real-time quantitative (q)PCR and western blotting, respectively. RESULTS: The stably transfected cell line HepG2-pn3.1-SHBs was established successfully. qPCR showed that the HepG2-pn3.1-SHBs cells had significantly down-regulated transcription of the ECHS1, APOA1 and LPL genes (0.161+/-0.043 vs. control cells: 0.210+/-0.022, t = 2.479; 0.031+/-0.007 vs. 0.094+/-0.055, t = 2.752; 0.770+/-0.036 vs. 0.982+/-0.031, t = 10.914), but significantly up-regulated ACC and SREBP-1c genes (0.113+/-0.027 vs. 0.059+/-0.022, t = -3.757; 0.019+/-0.002 vs. 0.015+/-0.001, t = -4.330). The CPT1a and PPARa genes' expression was slightly, but not significantly, down-regulated in the HepG2-pn3.1-SHBs cells (0.028+/-0.005 vs. 0.030+/-0.004, t = 1.022; 0.014+/-0.004 vs. 0.015+/-0.002, t = 0.758). Western blotting showed similar expression trends for the corresponding proteins. CONCLUSION: SHBs alters the expression of some host genes with known functions in fatty acid synthesis and decomposition; however, it remains unclear whether the hepatitis B surface antigen can directly contribute to development of hepatic steatosis.

Small hepatitis B surface antigen interacts with and modulates enoyl-coenzyme A hydratase expression in hepatoma cells.

Enoyl-coenzyme A hydratase (ECHS1) is a key enzyme in the metabolism of fatty acids in mitochondria. We previously reported that hepatitis B surface antigen (HBsAg) interacted with ECHS1 in a yeast two-hybrid system. In the current study, we further examined their interaction by using GST pull-down and co-immunoprecipitation assays. The results confirmed that small hepatitis B surface antigen (SHBs) interacted with ECHS1. Furthermore, confocal imaging showed that SHBs and ECHS1 co-localized in HepG2 cells. To clarify the biological function of the interaction, human hepatoma cell lines that transiently and stably expressed SHBs were generated. The expression of SHBs led to a significant decrease in ECHS1 protein levels. ECHS1 protein levels were reduced to 48.44 ± 7.12 % in Huh7 cells transiently expressing SHBs, and to 54.97 ± 3.54 % in HepG2 cells stably expressing SHBs. In conclusion, our findings suggest that SHBs interacts with ECHS1 and regulates ECHS1 protein levels in hepatoma cells.