Silencing of the long non-coding RNA NEAT1 suppresses ovarian cancer cell proliferation, migration and invasion

Increasing evidence reveals that long noncoding RNAs (lncRNAs) are involved in the development of various human cancers including ovarian cancer. LncRNA nuclear enriched abundant transcript 1 (NEAT1) is an essential structural determinant of nuclear body paraspeckles. Although aberrant expression and prognostic value of NEAT1 has been recently reported in various human cancers, NEAT1 was not fully investigated in ovarian cancer. Here, we reported that NEAT1 was upregulated in ovarian cancer tissues than noncancerous cyst tissues by realtime PCR. Furthermore, higher expression of NEAT1 was associated with more advanced tumor stage and bigger tumor size. Down-regulation of NEAT1 by siRNA transfection in two ovarian cancer cell lines, SKOV3 and OVCAR3 resulted in a significant decrease of cell proliferation via inducing cell cycle arrest and cell apoptosis. Additionally, we found that suppressing of NEAT1 expression notably repressed the migration and invasive ability of both ovarian cancer cell lines. More importantly, we investigated the possible mechanism how NEAT1 exerted its functions on ovarian cancer. NEAT1 siRNA treatment significantly affected the expression of cell apoptosis-associated proteins (Bcl-2, Bax, Caspase 3 and Caspase 9) and cell invasion-related proteins (MMP-2, MMP-9, Snail1 and TGF-β1). In summary, our study suggests that NEAT1 may serve as an oncogene in ovarian cancer.