Notch1 Affects Chemo-resistance Through Regulating Epithelial-Mesenchymal Transition (EMT) in Epithelial Ovarian cancer cells.

Background: Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy, chemo-resistance is the main cause for treatment failure. Our previous studies have found that SKOV3 could promote immune escape and tumor progression via Notch1 pathway. Therefore, Notch1 is suspected to be involved in chemo-resistance. The current study is to investigate the possible mechanisms of platinum-resistance in epithelial ovarian cancer mediated by Notch1. Methods: The expressions of Notch1, Snail, MMP-2, N-cadherin, Vimentin and E-cadherin were detected by Western-blot. A stable high expression or low expression of Notch1 in ovarian cancer cells was established by using lentiviral gene engineering. The cell migration and invasion ability were observed by scratch test and transwell test. Cell apoptosis rate and cell cycle were analyzed by flow cytometry. Results: The expression levels of Notch1, Snail, MMP-2, N-cadherin and Vimentin in ovarian cancer were high, while the expression levels of E-cadherin were low.Notch1 promoted the expression of Snail, vimentin, N-cadherin and MMP2 protein, but inhibiting the expression of E-cadherin, promoting cell migration and invasion. Notch1 affected apoptosis of cells through Epithelial-Mesenchymal Transition (EMT), increasing the proportion of cells in S phase and G2 phase, thus affecting drug resistance. Conclusion: Notch1 affects EOC cells chemo-resistance by regulating EMT. This may provide a new target for the treatment of ovarian cancer.