miR-145 inhibits glutamine metabolism through c-myc/GLS1 pathways in ovarian cancer cells.

miR-145 has been found to be a participant in cancer metastasis and glucose metabolism in ovarian cancer. However, the role of glutamine metabolism in ovarian cancer remains unclear. In this study, we aim to elucidate the molecular mechanism underlying the regulation of glutamine metabolism by miR-145 in ovarian cancer cells. The messenger RNA (mRNA) levels of miR-145 and glutaminase 1 (GLS1) were examined by quantitative real-time polymerase chain reaction (qRT-PCR). The protein levels of c-myc and GLS1 were detected by western blot analysis. Luciferase reporter assays were used to validate c-myc was a target of miR-145. Glutamine metabolism was analyzed using assay kits. In addition, we performed luciferase reporter assays and chromatin immunoprecipitation assay to validate c-myc transcription activated GLS1 and promoted GLS1 expression. The qRT-PCR demonstrated that the mRNA level of miR-145 and GLS1 was negatively correlated in ovarian cancer tissues and cell lines. Kaplan-Meier survival analysis and the log-rank test showed that patients with high miR-145 expression had significantly increased the overall survival. The overexpression of miR-145 inhibited glutamine consumption, α-ketoglutarate production, and cellular ATP levels. Furthermore, we found miR-145 inhibited glutamine metabolism by targeting c-myc. Moreover, c-myc could promote GLS1 expression by transcription activated. Together, our results revealed that miR-145 inhibited glutamine metabolism through c-myc/GLS1 pathways in ovarian cancer cells, which may improve the current strategy of ovarian cancer diagnosis and therapy.