miR-183 Enhances Autophagy of GC Cells by Targeted Inhibition of mTOR

Ann Clin Lab Sci. 2021 Nov;51(6):837-843.

Abstract

Objective: We investigated whether miR-183 played a role in regulating mTOR expression and influencing autophagy of GC cells.

Methods: Tumor tissues and paracancerous tissues were collected from GC patients to detect the expressions of miR-183, mTOR, autophagy-related proteins Beclin-1. SGC-7901 cells were cultured in vitro and divided into 5 groups: MiR-NC group, MiR-183 mimic group, si-NC group, small interfering RNA transfected (si)-mTOR group, miR-183 mimic + si-mTOR group, to compare the expression of mTOR, apoptosis rate and clonality in all groups, and detect the expressions of Beclin-1 under starvation condition.

Results: The expressions of miR-183, Beclin-1 in GC tissues were significantly decreased, and the expression of mTOR was significantly increased compared with those in paracancerous tissues. There was a targeted-regulating relationship between miR-183 and mTOR. Compared with GES-1 cells, miR-183 expression was decreased and mTOR expression was increased in SGC-7901 cells, and under starvation condition, the expressions of Beclin-1 were decreased. After transfected with miR-183 mimic and/or si-mTOR, the expression of mTOR in SGC-7901 cells was decreased significantly, the cell clonality was significantly reduced, apoptosis was increased significantly, and cell autophagy activity induced by starvation was significantly enhanced.

Conclusion: miR-183 can influence the proliferation, apoptosis and autophagy of GC cells through targeted inhibition of mTOR expression.

Keywords: Apoptosis; Autophagy; Gastric Cancer; PI3K/Akt/mTOR; Proliferation; miR-183.

MeSH terms

  • Apoptosis
  • Autophagy*
  • Beclin-1 / metabolism*
  • Cell Line, Tumor
  • Cell Proliferation
  • Clone Cells / pathology
  • Gene Expression Profiling / methods*
  • Gene Expression Regulation
  • Genes, Tumor Suppressor
  • Humans
  • MicroRNAs / genetics*
  • Stomach Neoplasms* / metabolism
  • Stomach Neoplasms* / pathology
  • TOR Serine-Threonine Kinases / metabolism*

Substances

  • Beclin-1
  • MIRN183 microRNA, human
  • MicroRNAs
  • MTOR protein, human
  • TOR Serine-Threonine Kinases