Long noncoding RNA SOX2OT contributes to gastric cancer progression by sponging miR-194-5p from AKT2

Highlights: • The role of SOX2/miR-194-5p/AKT2 axis in gastric cancer progression has been investigated. • SOX2OT acted as a sponge LncRNA of miR-194-5p in gastric cancer. • Suppressing SOXO2 expression can inhibit gastric cancer progression. Gastric cancer (GC) is a highly malignant cancer with poor prognosis. Long non-coding RNA (LncRNA) may play an important role in tumor progression. Our present study aimed to explore the effect of LncRNA SOX2OT on GC progression. We observed that SOX2OT was overexpressed in GC tissues and cell lines. Overexpressed SOX2OT promoted cell proliferation and metastasis of GC cells (SGC-7901, TMK-1) and the phosphorylation of AKT2 as well, while knockdown of SOX2OT reversed these effects. Besides that, miR-194-5p was predicted to be a target of SOX2OT and decreased expression of miR-194-5p was observed in GC tissues and cell lines. Overexpressed miR-194-5p counteracted the promoting role of SOX2OT on cell proliferation and invasion of GC cells. Moreover, AKT2 was predicted to be a target of miR-194-5p. The expression of AKT2 was negatively regulated by miR-194-5p while positively regulated by SOX2OT. Overexpressed AKT2 also promoted GC cell proliferation and invasion. Our in vitro experiments suggested that SOX2OT promoted cell proliferation and metastasis of GC cells via sponging miR-194-5p from AKT2. Finally, our in vivo experiments indicated that overexpressed SOX2OT promoted GC tumor growth and metastasis in nude mice. Taken together, our present study suggested that SOX2OT contributed to GC progression via sponging miR-194-5p from AKT2 both in vitro and in vivo. The SOX2OT-miR-194-5p-AKT2 axis may provide a new perspective for treatment of GC.