LncRNA GIHCG promotes development of ovarian cancer by regulating microRNA-429.

OBJECTIVE: To explore whether lncRNA GIHCG participates in the pathogenic progression of ovarian cancer (OC) and its underlying mechanism. PATIENTS AND METHODS: Expression levels of GIHCG and microRNA-429 in 30 OC tissues and normal ovarian tissues were detected by quantitative Real time-polymerase chain reaction (qRT-PCR). Subsequently, 15 pairs of OC tissues and paracancerous tissues were selected for correlation analyses of GIHCG, microRNA-429 and the overall survival (OS) of OC patients using Kaplan-Meier method. Pearson correlation analyses were conducted for investigating the correlation between GIHCG and microRNA-429. GIHCG expression in OC cell lines (HEY, A2780 and HO8910) and normal epithelial OC cell line (IOSE-386) was detected by qRT-PCR. After transfection of GIHCG overexpression plasmid in HEY cells, cell cycle, proliferation and colony formation ability were detected by flow cytometry, cell counting kit-8 (CCK-8) and colony formation assay. MicroRNA-429 expression in HEY cells overexpressing GIHCG was detected by qRT-PCR. Rescue experiments were conducted by co-transfection of GIHCG overexpression plasmid and microRNA-429 mimics, followed by cell cycle and colony formation detection. RESULTS: GIHCG was highly expressed, whereas microRNA-429 was lowly expressed in OC tissues than that of paracancerous tissues. OC patients with higher expression of GIHCG showed shorter OS than those with lower expression. However, OC patients with higher expression of microRNA-429 had longer OS than those with lower expression. GIHCG expression was positively correlated to microRNA-429. In vitro experiments showed that GIHCG was highly expressed in HEY, A2780 and HO8910 cells than that of IOSE-386 cells. GIHCG overexpression in HEY cells promoted cell cycle and colony formation abilities, which were reversed by microRNA-429 overexpression. CONCLUSIONS: GIHCG is highly expressed in OC, which promotes OC development by stimulating cell cycle progression and cell proliferation by regulating microRNA-429.