Role of reactive oxygen species (ROS) and JNKs in selenite-induced apoptosis in HepG2 cells.

Dietary selenium (Se) supplementation has been shown to be effective against reducing the risk of incidence of different human cancers. Selenium exists in both organic and inorganic forms. Different chemical forms of selenium metabolize differently in vivo, activate distinct molecular mechanisms and exhibit varying degree of anti-carcinogenicity in different cancer types. The effectiveness of a Se compound could also vary depending on the genetic background of the tumor cells. Therefore, understanding the molecular mechanism(s) by which different Se compounds exert their anti-tumorigenic effects is necessary for their use in cancer chemoprevention.