OBJECTIVE The synthetic triterpenoid 2-cyano-3,12-dioxoolean-1,9(11)-dien-C28-methyl ester(CDDO-Me)is considered a promising anti-tumorigenic compound.In this study,we investigated the anti-cancer effect of CDDO-Me on...OBJECTIVE The synthetic triterpenoid 2-cyano-3,12-dioxoolean-1,9(11)-dien-C28-methyl ester(CDDO-Me)is considered a promising anti-tumorigenic compound.In this study,we investigated the anti-cancer effect of CDDO-Me on breast cancer cells and its underlying mechanisms.METHODS To investigate the effect of CDDO-Me on various breast cancer cells,cell viability assay using calcein-AM and EthD-1 as well as MTT assay was performed.To clarify the origin of CDDO-Me-induced vacuoles,electron microscopy as well as fluorescence microscopy using YFP-ER or YFP-Mito construct was performed.To measure the changes in intracellular Ca2+and ROS levels,flow cytometry using Fluo-3 and H2DCF-DA was performed.RESULTS CDDO-Me treatment induces progressive ER-derived vacuolation and subsequent apoptosis in various breast cancer cells.CDDO-Me-induced increases in intracellular Ca2+ levels,reflecting influx from the extracellular milieu,make a critical contribution to ER-derived vacuolation and subsequent cell death.In parallel with increasing 2+ Calevels,CDDO-Me markedly increases the generation of reactive oxygen species(ROS).Interestingly,we found that there exists a reciprocal positive-regulatory loop between Ca2+ influx and ROS generation that triggers ER stress and ER dilation in response to CDDO-Me.CONCLUSION ER-derived vacuolation via Ca2+ influx and ROS generation is responsible for the potent anticancer effects of CDDOMe on breast cancer cells.展开更多
基金The project supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIP)(2011-0030043)a grant of the Korean Health Technology R&D Progect,Ministry of Health&Welfare(HI14C2230)
文摘OBJECTIVE The synthetic triterpenoid 2-cyano-3,12-dioxoolean-1,9(11)-dien-C28-methyl ester(CDDO-Me)is considered a promising anti-tumorigenic compound.In this study,we investigated the anti-cancer effect of CDDO-Me on breast cancer cells and its underlying mechanisms.METHODS To investigate the effect of CDDO-Me on various breast cancer cells,cell viability assay using calcein-AM and EthD-1 as well as MTT assay was performed.To clarify the origin of CDDO-Me-induced vacuoles,electron microscopy as well as fluorescence microscopy using YFP-ER or YFP-Mito construct was performed.To measure the changes in intracellular Ca2+and ROS levels,flow cytometry using Fluo-3 and H2DCF-DA was performed.RESULTS CDDO-Me treatment induces progressive ER-derived vacuolation and subsequent apoptosis in various breast cancer cells.CDDO-Me-induced increases in intracellular Ca2+ levels,reflecting influx from the extracellular milieu,make a critical contribution to ER-derived vacuolation and subsequent cell death.In parallel with increasing 2+ Calevels,CDDO-Me markedly increases the generation of reactive oxygen species(ROS).Interestingly,we found that there exists a reciprocal positive-regulatory loop between Ca2+ influx and ROS generation that triggers ER stress and ER dilation in response to CDDO-Me.CONCLUSION ER-derived vacuolation via Ca2+ influx and ROS generation is responsible for the potent anticancer effects of CDDOMe on breast cancer cells.