Effects of long non-coding RNA C5orf66-AS1 on the proliferation and apoptosis of gastric cancer cells by targeting miR-637

ObjectiveTo investigate the effects of long non-coding RNA C5orf66-AS1 on the proliferation and apoptosis of gastric cancer (GC) cells by targeting miR-637, so as to provide a basis for the clinical treatment of GC.

MethodsThe cancer tissues and adjacent tissues of 32 GC patients were collected.Human gastric adenocarcinoma cell lines MKN28, MKN451, BGC823, MGC803, AGS and normal gastric epithelial cell line GES-1 were cultured in vitro.The expression of C5orf66-AS1 and miR-637 was detected by qRT-PCR.AGS cells in logarithmic growth phase were transfected with liposome transfection reagent and divided into control group, GV144 group, GV144-C5orf66-AS1 group, miR-NC group, miR-637 mimics group, GV144-C5orf66-AS1 + miR-NC group, and GV144-C5orf66-AS1 + miR-637 mimics group.CCK-8 method was used to detect cell proliferation ability, flow cytometry was used to analyze the apoptosis, Western blotting was used to determine the expression levels of CyclinD1, B-cell lymphoma-2 gene (Bcl-2) and its homologous protein Bax of cells.RNA immunoprecipitation experiment was used to verify the relationship between C5orf66-AS1 and miR-637.

ResultsCompared with adjacent tissues or normal gastric epithelial cell line GES-1, the expression levels of C5orf66-AS1 and miR-637 in GC tissues and cell lines MKN28, MKN451, BGC823, MGC803, AGS were reduced (P < 0.05).The AGS cells with the lowest expression level of C5orf66-AS1 were selected for transfection experiments.After transfection of GV144-C5orf66-AS1, the C5orf66-AS1, miR-637 expression levels, apoptosis rate and Bax protein expression in AGS cells were significantly increased, and cell viability (48 h, 72 h, 96 h), CyclinD1 and Bcl-2 proteins were reduced (P < 0.05).There was an interaction between C5orf66-AS1 and miR-637.Moreover, the overexpression of miR-637 could make the overexpression of C5orf66-AS1 more effective in inhibiting AGS cell proliferation and promoting apoptosis (P < 0.05).

ConclusionsC5orf66-AS1 and miR-637 are lowly expressed in GC tissues and cells.Overexpression of C5orf66-AS1 and up-regulation of miR-637 can synergistically inhibit the proliferation of GC cells and promote apoptosis.