Abstract
Ovarian cancer (OC) is the leading cause of mortality among gynecological malignancies. Although microRNAs are known to have a key regulatory role in OC, the involvement of long non-coding RNAs in the disease is less established. Previous studies have demonstrated that metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a tumor oncogene in many cancers, though its role in OC remains unclear. The present study reported that MALAT1 expression was markedly upregulated in OC, by knockdown of MALAT1 expression in vivo, using RNA interference (RNAi) with small-interfering RNA (siRNA). It was found that MALAT1 expression was positively correlated with the International Federation of Gynecology and Obstetrics stages of OC, tumor histological grade and lymph node metastasis. In addition, the differential MALAT1 levels between a human ovarian epithelial cell line (HOSE) and OC cell lines (ES-2, OVCAR3, SKOV3 and HO8910) were compared in vitro. Notably, MALAT1 was expressed to a high level in OC cells. Furthermore, exogenous knockdown of MALAT1 significantly repressed growth and migration of OC cells, and promoted their apoptosis. Collectively, the current findings suggest that upregulation of MALAT1 in OC may facilitate tumorigenesis and metastasis. Knockdown of MALAT1 expression has potential as a novel target for the diagnosis and therapy of OC.