LINC‐PINT suppresses tumour cell proliferation, migration and invasion through targeting miR‐374a‐5p in ovarian cancer

LncRNA LINC‐PINT acts as an important regulator in the development of many cancers. The current study aimed to explore the role of LINC‐PINT in the progression of ovarian cancer (OC). LINC‐PINT expression level in different FIGO stages of OC and its adjacent tissues, normal HOSE and OC cell lines (A2780, SKOV3, OVCAR3 and HO‐8910) was determined by qRT‐PCR. Survival analysis on LINC‐PINT and OC patients was conducted by Kaplan‐Meier. CCK‐8, flow cytometry, wound‐healing, Transwell assays and western blot were performed to detect the effects of LINC‐PINT on proliferation, apoptosis, migration, invasion and EMT process in OC cells. Target gene of LINC‐PINT was predicted by Starbase and verified by dual‐luciferase reporter assay. The expression of miR‐374a‐5p in normal and OC tissues, LINC‐PINT‐ or siLINC‐PINT‐modified OC cells was determined. Moreover, rescue assay was carried out to confirm whether LINC‐PINT contributes to the development of OC cells through targeting miR‐374a‐5p. Low expression of LINC‐PINT was observed in OC tissues and cells, noticeably, LINC‐PINT expression was even lower in OC tissues with higher FIGO stage. Increased LINC‐PINT expression significantly inhibited cell proliferation, promoted apoptosis and suppressed migration, invasion and EMT process, while silencing of LINC‐PINT caused the opposite results. Moreover, LINC‐PINT sponged miR‐374a‐5p and overexpressed miR‐374a‐5p attenuated the effect of up‐regulated LINC‐PINT on cell viability, migration, invasion and apoptosis. LINC‐PINT acts as a tumour suppressor, as it could inhibit cell proliferation, migration, invasion and EMT process, and promote cell apoptosis through down‐regulating miR‐374a‐5p. Significance of the study Ovarian cancer (OC), which is a frequently diagnosed tumour in female reproductive organs, has a high incidence rate behind cervical cancer and endometrial cancer. LncRNA LINC‐PINT acts as an important regulator in the development of many cancers. The current study aimed to explore the role of LINC‐PINT in the progression of ovarian cancer (OC) and found that LINC‐PINT inhibited cell proliferation, migration invasion and EMT process of OC cell via regulating miR‐374a‐5p; it might be a potential target for OC treatment.