Stimulation of Differentiated Functions in Human Melanoma Cells by Tumor-promoting Agents and Dimethyl Sulfoxide

摘要: Treatment of cultured human HO melanoma cells with the mouse skin tumor promoter phorbol-12-myristate-13-acetate (PMA) at 5 x 10/sup -10/ to -7/ M resulted in a dose-related inhibition growth and stimulation differentiated functions. These included melanin synthesis formation dendrite-like structues. Higher doses phorbol dibutyrate, less potent promoter, were required produce an effect comparable that PMA for dendrite induction. Phorbol two other phorbal esters, which lack tumor-promoting activity, either inactive or elicited poor response. In addition morphological changes, treatment altered glucosamine incorporation into membrane gangliosides. After treatment, increased 8- 10 fold G/sub m3/ ganglioside decreased 2-fold m1/ ganglioside, as compared untreated control. Inhibition cell also observed after dimethyl sulfoxide. Unlike agents, sulfoxide did not induce structures cells. findings indicate can be stimulated terminally agents such diesters.