Melanocytotoxicity and antimelanoma effects of phenolic amine compounds in mice in vivo
Alena, F.; Jimbow, K.; Ito, S.
Cancer Research 50(12): 3743-3747
1990
ISSN/ISBN: 0008-5472 PMID: 2340520 Document Number: 362257
A phenolic amine compounds, 4-S-cysteaminylphenol (4-S-CAP), is a potent depigmenting agent. To develop more efficacious antimelanoma agents, we synthesized four homologues of 4-S-CAP: N-acetyl-4-S-CAP (N-Ac-4-S-CAP), .alpha.-methyl-4-S-CAP, 4-S-homo-CAP, and N,N'-dimethyl-4-S-CAP. We tested these five compounds in mice in vivo. After s.c. or i.p. injection of saline solution (in control groups) or one of the compounds, follicular melanocytes were examined by light and electron microscopy to assess the degree of melanocytotoxicity; N-Ac-4-S-CAP induced the most depigmentation (98%), whether given i.p. or s.c. After injection of 4-S-CAP or N-Ac-4-S-CAP, the number of murine B16F10 melanoma colonies formed in the lungs was determined; 4-S-CAP and N-Ac-4-S-CAP were almost equally effective, reducing the colonies to 32 and 25% of mean control, respectively. Metabolic studies of the urine showed 9% of 4-S-CAP and 20% of N-Ac-4-S-CAP injected i.p. were excreted unchanged in 24 h; 1.3% of the N-Ac-4-S-CAP was excreted as 4-S-CAP, indicating some conversion. We conclude that N-Ac-4-S-CAP is a suitable model for developing chemotherapy to treat melanoma characterized by high tyrosine activity and melanin synthesis.