Curcumin, curcuma longa, has been known to exert anti-oxidant effects or anti-inflammatory effects as phytochemical. Also it induces apoptosis in the colon cancer cells and inhibits an angiogenesis of tumor. AMP-activated protein kinase (AMPK) is activated by ATP depletion status such as heat shock, exercise, hypoxia, reactive oxygen species (ROS). Recent studies indicate that AMPK activation strongly suppresses cell proliferation and induces apoptosis in cancer cells. Hence, AMPK plays a critical role as a key signal in prevention of cancer and obesity. In this study, curcumin generated ROS in HT-29 colon cancer cell lines and this ROS seemed to be closely related to an increase in AMPK activation. ROS generated by phytochemical is one of the responsible elements for the activation of AMPK. We hypothesized that combined treatment of H₂O₂ and curcumin more stronglyactivated AMPK and this effect was abolished by AMPK inhibitor Compound C in HT-29 cells. Our results suggest that combined treatment of H₂O₂ and curcumin is an effective way in controlling cancer proliferation and apoptosis. Also, the synergistic effect of H₂O₂ and curcumin were shown to potent a chemotherapy in colon cancer cells. (Cancer Prev Res 14, 225-232, 2009)

Keywords: Curcumin, ROS, AMPK, H₂O₂, Apoptosis