L-HOMOSERINE HYDROXAMIC ACID AS AN ANTITUMOR AGENT

This report confirms the potent mutagenic and antitumor activity of L- homoserine hydroxamic acid in both in vitro and in vivo test systems. Its mutagenic potential is evident in the developing tadpoles of Xenop us laevis eggs exposed to the compound. Cytotoxic effects are demonstr ated against human leukemia and melanoma cell lines proliferating in t issue culture and against xenografts of human breast cancer and sarcom a growing in nude mice. We propose that the mutagenic and antitumor ac tivity are mediated through hydroxylamine, which is released from its stable carrier amino acid, homoserine, consequent to a reduction in pH occurring at the cellular level. The cytotoxic effects of L-homoserin e hydroxamic acid are more intense than those of the D-isomer and are more evident in neoplastic than in normal cell lines.