The expression and biological function of long intergenic noncoding RNA00265 (LINC00265) in gastric cancer (GC) have not yet been explored. This study aimed to detect LINC00265 expression in GC tissues and cell lines, investigate its roles in the proliferation of GC cells in vitro, and elucidate the regulatory mechanisms of LINC00265 action. It was found that LINC00265 expression was significantly upregulated in GC tissue samples and cell lines compared with their normal counterparts. Additionally, LINC00265 knockdown could inhibit GC cell proliferation in vitro. Further investigation revealed that LINC00265 acted as a competing endogenous RNA for microRNA-144-3p (miR-144-3p) and inhibition of miR-144-3p markedly counteracted LINC00265 knockdown-meditated suppression on GC cell proliferation. Additionally, Chromobox 4 (CBX4) was upregulated in GC and silencing CBX4 could reduce GC cell proliferation. Then, CBX4 mRNA was demonstrated to be a direct target of miR-144-3p in GC cells and LINC00265/miR-144-3p axis could regulate CBX4 expression. Taken together, LINC00265 may promote GC cell proliferation via the miR-144-3p/CBX4 axis.
Keywords: LINC00265; competing endogenous RNA; gastric cancer; microRNA-144-3p.