ABSTRACT
<p><b>BACKGROUND</b>Human epididymis secretory protein 4 (HE4) has been proved to be a promising novel biomarker for the detection of epithelial ovarian carcinomas. Compared with CA125, HE4 assay demonstrated an improved ability to discriminate between pelvic mass with malignant and benign disease. Though it is well known that HE4 is overexpressed in ovarian cancer, however, the role of HE4 in the carcinogenesis and progression of ovarian cancer remains unkown.</p><p><b>METHODS</b>In this study, we explored the role of HE4 in the carcinogenesis and progression of ovarian cancer. We screened nine ovarian cancer cell lines for HE4 expression, and using RNA interference (RNAi), we silenced HE4 gene expression in CaoV3 and SKOV3.ip1 ovarian cancer cell lines. We assessed the effect of HE4 gene silencing on the transformed phenotype by examining the cell cycle, apoptosis, proliferation and transwell migration/invasion in vitro.</p><p><b>RESULTS</b>HE4 gene silencing induces G0/G1 arrest and blocks the progression from the G1 to S phase in CaoV3 and SKOV3.ip1 cells. HE4 knockdown also inhibited cell proliferation, migration and invasion in SKOV3.ip1 cells in vitro.</p><p><b>CONCLUSION</b>HE4 may be involved in the regulation of the cell cycle and promote ovarian cancer migration and invasion.</p>