miR-183 inhibits autophagy and apoptosis in gastric cancer cells by targeting ultraviolet radiation resistance-associated gene

Int J Mol Med. 2018 Dec;42(6):3562-3570. doi: 10.3892/ijmm.2018.3871. Epub 2018 Sep 11.

Abstract

Ultraviolet radiation resistance‑associated gene (UVRAG) regulates autophagy by promoting the formation and maturation of autophagosomes. The aim of the present study was to investigate the effects of UVRAG and UVRAG‑targeting miRNA on the regulation of autophagy and apoptosis in gastric cancer (GC). TargetScan was used to predict that miR‑183 targets the 3'‑untranslated region (UTR) of UVRAG, while the interaction between miR‑183 and the 3'‑UTR of UVRAG was assessed using a dual luciferase reporter assay. Autophagy was induced in the GC cell line MKN28 by serum starvation. miR‑NC mimics, miR‑183 mimics, miR‑NC inhibitors and miR‑183 inhibitors were transfected into MKN28 cells, followed by assessment of the UVRAG expression, cell viability and cell apoptosis by western blotting, reverse transcription‑quantitative polymerase chain reaction, Cell Counting Kit‑8 and flow cytometry, respectively. It was demonstrated that autophagy resulted in miR‑183 downregulation and overexpression of UVRAG mRNA and protein in MKN28 cells. Transfection with miR‑183 mimic or inhibitor affected the expression of miR‑183 and, consequently, UVRAG. miR‑183 overexpression reversed the starvation‑induced inhibition of cell proliferation, while inhibition of miR‑183 reduced the proliferation of GC cells. miR‑183 overexpression reversed starvation‑induced apoptosis, while miR‑183 inhibition promoted starvation‑induced apoptosis in GC cells. Finally, miR‑183 overexpression attenuated starvation‑induced autophagy (LC‑3), apoptosis (Bax/Bcl‑2) and UVRAG expression, while miR‑183 inhibition exerted the opposite effects. In conclusion, the results of the present study indicated that miR‑183 inhibits starvation‑induced autophagy and apoptosis by targeting UVRAG in human GC cells.

MeSH terms

  • Apoptosis / genetics*
  • Autophagy / genetics*
  • Cell Line, Tumor
  • Cell Survival / genetics
  • Down-Regulation / genetics
  • Gene Expression Regulation, Neoplastic
  • Humans
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Microtubule-Associated Proteins / metabolism
  • Stomach Neoplasms / genetics*
  • Stomach Neoplasms / pathology*
  • Tumor Suppressor Proteins / genetics
  • Tumor Suppressor Proteins / metabolism*
  • Up-Regulation / genetics
  • bcl-2-Associated X Protein / metabolism

Substances

  • MAP1LC3A protein, human
  • MIRN183 microRNA, human
  • MicroRNAs
  • Microtubule-Associated Proteins
  • Tumor Suppressor Proteins
  • UVRAG protein, human
  • bcl-2-Associated X Protein