6-Gingerol exerts anti-tumor effects in various cancer cell models. We evaluated the effect of 6-gingerol on the growth of MCF-7 breast cancer cells and MCF-10A breast epithelial cells to determine whether any growth-inhibitory effects found were attributable to apoptosis, and to elucidate the underlying mechanism of action. 6-Gingerol inhibited the viability of both cell lines in a dose- and time-dependent manner; however, the degree of inhibition was greater in MCF-7 than MCF-10A cells. By flow cytometry, induction of dose- and time-dependent apoptosis was found, and the magnitude of apoptosis was also markedly greater in MCF-7 than MCF-10A cells. Expression of caspase-3 and poly (ADP-ribose) polymerase (PARP) was observed in MCF-7 cells treated with 6-gingerol, and further cleavage of PARP occurred in these cells. We suggest that 6-gingerol induces apoptosis in human breast cancer cells mainly by promoting caspase-3 expression and subsequent degradation of PARP.

[6]-Gingerol, a major polyphenol of ginger(Zingiber officinale), exhibits a variety ofbiological properties including anti-oxidant, anti-inflammatory and anti-cancer activity. However,the radioprotective effect of [6]-gingerol is still unknown. The aim of this study was to investigatethe radioprotective effect of [6]-gingerol against radiation-induced cell cytotoxicity and oxidativestress in HepG2 cells. [6]-Gingerol pretreatment attenuated radiation-induced cell cytotoxicitycaused by 5Gy(half lethal dose, LD50of HepG2 cells). The measurements of superoxide dismutase(SOD) and catalase(CAT) activity were also performed. The results showed that [6]-gingerol pre-treatment reduced increasing SOD and CAT activity after exposure of IR, indicating that [6]-gin-gerol protected oxidative stress by regulating cellular antioxidant enzyme(SOD and CAT) activity.These findings suggest that [6]-gingerol acts as a radioprotector by attenuating cell cytotoxicityand oxidative stress.