Watercress has it. So does cauliflower, cabbage, bok choy, broccoli, and brussels sprouts. Phenethyl Isothiocyanate (PEITC) is another powerful, natural anti-cancer compound. It works by manipulating redox status in the cell. Follow the links for some of the research on this powerful glutathione inhibitor.
Stromal control of cystine metabolism promotes cancer cell survival in chronic lymphocytic leukemia
Effective elimination of fludarabine-resistant CLL cells by PEITC through a redox-mediated mechanism
Phenethyl Isothiocyanate (PEITC) Regulates Autophagy in Chronic Lymphocytic Leukemia