A review on the anti-mutagenic and anti-cancer effects of Cysteamine

Cysteamine is an aminothiol endogenously synthetized by human cells during the degradation of coenzyme A. Since the 1950s, this substance has been used in radiation protection, immunomodulation, and is the sole FDA-approved oral agent for the treatment of cystinosis. Many in vitro and in vivo studies recommend cysteamine as an effective anti-carcinogenic agent. In this article, we will review the preventive and therapeutic effects of cysteamine for 3 types of cancers: carcinomas, sarcomas and melanomas. Cysteamine has been shown to be effective in vitro and in vivo for the treatment of different cancer types generally leading to the significant reduction of lesions and/or the increase of survival time. Cysteamine has been shown to enhance the anti-melanoma effect of doxorubicin in vivo and cysteamine derivatives have shown anti-melanoma efficacy in animal models. Although the mechanisms of action are not fully understood, possible explanations on the pathophysiology of cell suppression by cysteamine are given : (i) free radical scavenging (ii) alteration of the tumor cell proliferation by affecting nucleic acid and protein synthesis or inhibition of DNA synthesis (iii) hormone regulation.