ATF5 Is Overexpressed in Epithelial Ovarian Carcinomas and Interference With Its Function Increases Apoptosis Through the Downregulation of Bcl-2 in SKOV-3 Cells

The activating transcription factor 5 (ATF5) is highly expressed in many kinds of tumors including glioblastoma and breast cancers, but its expression in epithelial ovarian neoplasms has not been investigated. Here, we show that ATF5 is highly expressed in the majority of epithelial ovarian cancer samples (43/60) as compared with benign ovarian tumor tissues (4/13) and normal ovarian tissues (1/10). Furthermore, we found that ATF5 expression significantly correlated with advanced clinical stage (P<0.05) and poor differentiation of epithelial ovarian carcinomas (P<0.05). Previous studies suggested that ATF5 is required for the survival of cancer cells, but the mechanisms by which ATF5 regulates genes and promotes cell survival are not clear. Our data additionally demonstrated that interference with the function of ATF5 could markedly increase the apoptosis of ovarian cancer cells and identified B-cell leukemia lymphoma-2 as an ATF5-targeted apoptosis-related gene. These findings may provide potential therapeutic application in epithelial ovarian cancer.