MicroRNA-183 affects the development of gastric cancer by regulating autophagy via MALAT1-miR-183-SIRT1 axis and PI3K/AKT/mTOR signals

Abstract

Gastric cancer (GC) remains to be a familiar malignant tumor with poor prognosis and daunting impacts on global health. We planned to grab the latent impacts of microRNA-183 in regulating cell autophagy, thus to clarify its possible regulatory principle in GC. The miR-183 level in GC tissues and cell lines was investigated. The impacts of miR-183 dysregulation on cell biological performances including viability, apoptosis and autophagy of GC cell lines including SGC-7901 were detected. Also, cells were disposed with 3-methyladenine (3-MA, an autophagy inhibition) before dysregulation of miR-183 to further investigate the correlation between cell autophagy and viability or apoptosis. Furthermore, the regulatory mechanisms between miR-183 and metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), silent mating type information regulation 1 (SIRT1) or PI3K/AKT/mTOR pathway were explored. miR-183 was under-expressed both in GC tissues and in cell lines. miR-183 mimic alone depressed SGC-7901 cell viability and enhanced cell apoptosis and autophagy, whereas miR-183 inhibitor exhibited opposite effects. Moreover, the impacts of miR-183 on SGC-7901 cell viability and apoptosis were mediated by affecting the activation of autophagy. Our results indicate that miR-183 is under-expressed in GC cells and depression of miR-183 may enhance GC cell viability and inhibit cell apoptosis by affecting the activation of cell autophagy. MALAT1-miR-183-SIRT1 axis and PI3K/AKT/mTOR pathway may be mechanisms to mediate autophagy in GC. miR-183 may serve as a towardly therapeutic target for GC.

Keywords: Gastric cancer; MALAT1; PI3K/AKT/mTOR signals; miR-183; silent mating type information regulation 1 (SIRT1).