TYROSINASE INHIBITOR IN FORTNERS AMELANOTIC AND MELANOTIC MALIGNANT MELANOMA

[摘要] The defects in melano-genesis in amelanotic melanoma may be attributed in part to disturbed tyrosinase synthesis and the presence of inhibitors since melanosome formation and active tyrosine release utilizable as substrate has been shown in amelanotic melanoma. Fortner''s amelanotic melanoma type 3 exhibited no tyrosinase activity in 20 cases presently studied. Removing inhibitor from amelanotic fractions by dialysis failed to reveal tyrosinase activity. The characteristic properties of inhibitor found in both melanotic and amelanotic melanoma are heat stability, dialyzable, not a sulfhydryl compound, and competitive inhibition.