YAP promotes the malignancy of endometrial cancer cells via regulation of IL-6 and IL-11

Background: Emerging evidence shows that Hippo signal pathways can regulate the progression of various cancer. While the roles of Yes-associated protein (YAP), the key transducer of Hippo signals, in the development of endometrial cancer (EC) are rarely investigated. Methods: The expression of YAP in endometrial cancer cells and tissues was measured. Its roles in proliferation and expression of interleukins (ILs) were investigated by use of its specific siRNA or inhibitor (verteporfin, VP). Results: YAP was upregulated in endometrial cancer cells and tissues. Knockdown of YAP or VP can suppress the proliferation while increase its chemo-sensitivity of EC cells. We found that targeted inhibition of YAP can decrease the expression of interleukin-6 (IL-6) and IL-11 in EC cells. Recombinant IL-6 or IL-11 can attenuate si-YAP suppressed proliferation of EC cells. Chromatin immunoprecipitation (ChIP) assay suggested that YAP can directly bind with the promoter of IL-6 and induce its transcription. As to IL-11, inhibitor of NF-kappa B (BAY 11-7082) can significantly down regulate the mRNA expression of IL-11. Over expression of p65 abolished si YAP suppressed transcription of IL-11. It suggested that NE-kappa B was involved in the YAP regulated expression of IL-11. Conclusions: YAP can regulate the proliferation and progression of EC cells. It suggested that targeted inhibition of YAP might be a potent potential approach for EC therapy.