Diosgenin exhibits tumor suppressive function via down-regulation of EZH2 in pancreatic cancer cells

Pancreatic cancer (PC) is one of the most aggressive and lethal malignancies worldwide. Although significant progress has been made in oncology treatment, this refractory disease is still become intractable. Natural herb product diosgenin is described to exhibit vast range of pharmacological activities in preclinical studies, including anti-cancer activities. Accumulating data demonstrated that Enhancer of zeste homolog 2 (EZH2) as an oncogenic protein is over-expressed in various human cancers, including PC. However, the underlying mechanism has not been fully understood. In this study, we aim to investigate the anti-cancer properties and molecular basis of diosgenin in PC cells. Significant inhibition of cell proliferation was observed in diosgenin treated Patu8988 and Panc-1 cells in a dose- and time-dependent manner. Apoptotic cell death and G2/M phase arrest were also induced by diosgenin treatment in PC cells. Moreover, obvious inhibition of cell migration and invasive capacities was detected in diosgenin treated PC cells. Mechanistically, the expression levels of EZH2 and its target Vimentin were reduced, and PTEN was promoted after diosgenin exposure. Our results further supported that EZH2 signaling was closely associated with the anti-tumor characteristics of diosgenin in PC cells. Therefore, inhibition of EZH2 by diosgenin could be a promising therapeutic method for PC treatment.