Profiling and Characterization of microRNAs Responding to Sodium Butyrate Treatment in Gastric Cancer Cells

Background: Short-chain fatty acids exert anti-cancer effects on tumor cells. Objective: We aimed to reveal the signaling network altered by butyrate in Gastric Cancer (GC) using small RNA sequencing (sRNA-seq). Methods: The effects of butyrate on the biological behavior of NCI-N87 and KATO III cells in vitro were assessed by functional assays and half-maximal inhibitory concentrations (IC50) of butyrate in KATO III cells were calculated. sRNA-seq was performed on KATO III cells. Differentially expressed miRNAs (DE-miRNAs) were identified between butyrate treatment and control groups using DESeq2, and miRNA targets were predicted. A protein-protein interaction (PPI) network of DE-miRNA targets was created using Metascape. Key MCODE complexes were identified using the MCODE algorithm and cluster Profiler. The relationship between DE-miRNA and GC overall survival (OS) was evaluated using Kaplan-Meier curves. Results: Butyrate dose-dependently inhibited NCI-N87 and KATO III cell viability. KATO III cells were more sensitive to butyrate than NCI-N87 cells. Butyrate promoted apoptosis and inhibited KATO III cell migration. Total 324 DE-miRNAs were identified in KATO III cells, and 459 mRNAs were predicted as targets of 83 DE-miRNAs. Two key protein complexes were identified in a PPI network of the 459 targets. A key signaling network responding to butyrate was generated using targets in these key complexes and their miRNA regulators. The DE-miRNAs in the key signaling network were related to the OS of GC. Conclusion: Butyrate altered the biological behavior of GC cells, which may be achieved by regulating miRNAs and related oncogenic pathways.