NCIt definition : The sodium salt of selenium. As a trace mineral that is toxic in high doses, selenium
is a cofactor for glutathione peroxidase, an anti-oxidant enzyme that neutralizes
hydrogen peroxide. Selenium may be chemoprotective for certain cancers, particularly
prostate cancer. High dietary supplementation with sodium selenate may inhibit the
progression of hormone-refractory prostate cancer due, in part, to an antiangiogenesis
effect. (NCI04);