Modification of Melanogenesis in Cultured Human Melanoma Cells

• Published in: In vitro cellular & developmental biology. Animal 1999-11, Vol.35 (10), p.564-565
• Main Authors: Slominski, A, Ermak, G, Wortsman, J
• Format: Article
• Language: English
• Subjects: Animals; Blotting, Northern; Cell culture techniques; Cellular metabolism; Complementary DNA; Cricetinae; Culture Media; Cultured cells; Delta cells; Gene expression regulation; Humans; Melanin; Melanins - biosynthesis; Melanocytes; melanogenesis-related proteins; Melanoma; Melanoma - enzymology; Melanoma - metabolism; Melanoma - pathology; Monophenol Monooxygenase - metabolism; Pigmentation; Scientific Reports; Tumor Cells, Cultured; tyrosine
• ISSN: 1071-2690; 1543-706X
• DOI: 10.1007/s11626-999-0093-6

Melanogenesis is a marker of differentiation in melanocytes. In addition, melanogenesis can profoundly affect the biologic behavior of melanoma cells as well as that of the surrounding environment. That biochemical process, which results in the transformation of L-tyrosine to melanin, involves precise interactions between the melanogenesis-related proteins (MRP) including enzymes and regulatory and structural proteins. Melanogenesis takes place in melanosomes and requires simultaneous delivery of L-tyrosine (substrate) and tyrosinase (the main and obligatory enzyme of the pathway) to these organelles. Melanogenesis is regulated by hormonal and nutritional factors, especially L-tyrosine (substrate for tyrosinase) whose concentration determines the actual amount of melanin produced. Among the hormonal regulators of melanin synthesis, the most important is alpha-melanocyte-stimulating hormone ( alpha -MSH), which interacts with a specific cell surface receptor (MC-1R) to stimulate melanin synthesis and other differentiated functions of melanocytes. Human melanoma lines have been established in vitro, and because of their phenotypic stability, are convenient models for studies on the mechanisms regulating melanoma behavior. To this end, we routinely culture melanoma cells using Ham's F-10 or Dulbecco's modified essential medium (DMEM). In this regard, we have recently found that the human melanoma line SKMEL188 (gift of Dr. Chakraborty from Yale University) changes its level of pigmentation in a reproducible manner, according to the specific culture medium used. Since the hamster amelanotic melanoma line shows profound metabolic and cellular changes accompanying the induction of melanin synthesis by DMEM or L-tyrosine, we tested whether the changes in pigmentation level in human melanoma cells are similarly accompanied by increased expression of tyrosinase and MC-1R genes.