Inhibiting endoplasmic reticulum stress mediated-autophagy enhances the pro-apoptotic effects of resveratrol derivative in colon cancer cells.

Previous studies have demonstrated that endoplasmic reticulum stress (ERS) might play a major role in inducing cellular autophagy and apoptosis in multiple types of cancer. Herein, we observed that trans-3,5,4'-trimethoxystilbene (TMS) exposure facilitated apoptotic cell death and ERS-mediated autophagy in colon cancer SW480 and HCT116 cells. Interestingly, our data demonstrated that ERS was not involved in TMS-induced apoptosis. However, ERS notably induced protective autophagy in SW480 and HCT116 cells. In addition, inhibiting cellular ERS significantly improved the pro-apoptotic effects of TMS. Thus, our results indicated that TMS-mediated autophagy was dependent on ERS, while apoptotic cell death might be induced in the ERS-independent pathway after TMS treatment. Generally, inhibiting ERS-mediated autophagy can enhance the pro-apoptotic effects of TMS. TMS might be a potential therapeutic agent for colon cancer treatment.