This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Wick, M. M. Articles by Frei, E. Search for Related Content PubMed PubMed Citation Articles by Wick, M. M. Articles by Frei, E., III

Selective Incorporation of L-3,4-Dihydroxyphenylalanine by S-91 Cloudman Melanoma in Vitro¹

The Sidney Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115

The incorporation of precursors of the biopigment melanin into melanotic and amelanotic S-91 Cloudman melanoma, mouse fibroblast L-929, and Chinese hamster ovary cells was studied. Tyrosine did not selectively accumulate in pigmented cells compared to that in nonpigmented control cells. Inhibition of protein synthesis with cycloheximide provided an estimate of the partition of tyrosine between protein (95%) and pigment biosynthesis (5%).

L-3,4-Dihydroxyphenylalanine, a more proximal precursor of melanin, was selectively incorporated into pigmented cells up to 60 times that of control lines. -Melanocyte-stimulating hormone and theophylline, agents that enhance pigmentation, further increased the incorporation of L-3,4-dihydroxyphenylalanine into melanocytic cells. A unique property of melanoma cells thereby has been defined that may permit a selective chemotherapeutic and diagnostic approach.

¹ This investigation was supported in part by NIH Grant CA-06516.

Received 1/14/77. Accepted 4/ 1/77.