N⁶,O²′-Dibutyryl Adenosine 3′,5′-Monophosphate induces Pigment Production in Melanoma Cells

Abstract

IN VITRO studies have suggested that adenosine 3′,′-monophosphate (cyclic AMP) regulates cell morphology. During treatment with the dibutyryl analogue of cyclic AMP, N⁶,O²′-dibutyryl cyclic AMP, transformed fibroblasts acquire several morphological characteristics of untransformed fibroblasts^1,3. Cell processes are extended, the cells occupy a greater surface area and in some cases there is a parallel alignment of cells. Chinese hamster ovary cells are affected in the same way. In neuroblastoma cells⁵, dibutyryl cyclic AMP induces neurite extension and increases the activity of acetylcholinesterase, an indicator of biochemical differentiation⁶. Cyclic AMP is known to control the dispersion of melanin^7,8 and the differentiation of melanoblasts into melanocytes. We have now found that during treatment with dibutyryl cyclic AMP, melanoma cells spread out, appear larger and produce considerably more pigment than untreated cells.