Long non-coding RNA FTX promotes gastric cancer progression by targeting miR-215.

OBJECTIVE: Gastric cancer (GC) is one of the most common malignant tumors in the world, which is seriously harmful to people's health. The increasing number of studies have shown that long non-coding RNA (lncRNA) is related to the occurrence of gastric cancer. In this study, we aimed at investigating the role of lnc FTX in the occurrence of gastric cancer. MATERIALS AND METHODS: The expression of FTX in gastric cancer patients and gastric cancer cell lines was detected by RT-qPCR. Univariate Kaplan-Meier method was used to analyze the relationship between FTX expression level, clinicopathological parameters and overall survival rate (OS). After transferring si-FTX and overexpression FTX plasmids into MGC-803 and SGC-7901, the expression of miR-215-3p was detected by RT-qPCR, and the changes of cell proliferation and cell cycle were detected by CCK-8 and flow cytometry. In addition. luciferase activity was used to detect whether miR-215-3p combined with FTX and SIVA1. Finally. Western blot (WB) was used to detect the change of SIVA1 protein expression by miR-215 mimic. RESULTS: We found that the expression of FTX in tumor tissues of 71 GC patients was higher than that in paracancerous tissues, and the prognosis of patients with high FTX was poor. The expression of FTX in gastric cancer cells was higher than that in normal human gastric epithelial cells (GES-1). Transferring overexpression plasmid of FTX into gastric cancer cells (MGC-803 and SGC-7901) promoted cell proliferation and the ratio of cells in GO-G1 phase was decreased. Transferring si-FTX to MGC803 and SGC-7901 led to opposite results. There was a negative correlation between the expression of mi215-3p and FTX in MGC-803 and SGC7901 gastric cancer cells, and luciferase results showed that mi215-3p could directly bind to FTX and regulate cell growth and cell cycle changes. In addition, luciferase results showed that mi215-3p could bind directly to SIVA1. What's more, RT-qPCR and WB results showed that mi215 mimic could promote the expression of MGC-803, SGC-7901 SIVA1mRNA and protein. CONCLUSIONS: According to these results, this study revealed that the previously neglected FTX-miR2153p-SIVA1 regulatory axis for the regulation of gastric cancer progression, which may be a potential target for the treatment of gastric cancer.