ALPHA-MELANOCYTE-STIMULATING HORMONE BINDING AND BIOLOGICAL-ACTIVITY IN A HUMAN-MELANOMA CELL-LINE

  • 1 January 1981
    • journal article
    • research article
    • Vol. 41  (4) , 1539-1544
Abstract
Synthetic .alpha.-melanocyte-stimulating hormone (.alpha.-MSH) band to the plasma membrane of the HM6A human melanoma cell line. When treated with 10-7 to 10-9 M .alpha.-MSH, melanoma cells exhibited an increase of intracellular cAMP followed by stimulation of tyrosinase activity. Significant inhibition of DNA synthesis measured by [3H]thymidine uptake and inhibition of cell growth was found. A retrovirus expression was detected in the supernatant of HM6A cells as assayed by the KC cell syncytium-forming test. In the presence of 10-7 M .alpha.-MSH, the number of syncytium-forming units was increased 15-fold. .alpha.-MSH modulates human melanoma differentiation and virus expression in vitro.