Scanning electron microscopy of human and murine melanoma cells exposed to medium chain-length (C6-C12) dicarboxylic acids in tissue culture.

Human and murine (Harding-Passey and Cloudman) melanoma cells were exposed to various concentrations (1 x 10(-3) M-1 x 10(-1) M) of adipic (C6), azelaic (C9), and dodecanedioic (C12) acids for 1-6 hours in tissue culture, and the effects on shape and surface topography were examined by scanning electron microscopy. Effects, i.e., rounding up, concentration of microvilli, blebbing, and prominence of retraction fibrils were time and dose dependent, and for the same concentrations and exposure times, C12 had a greater effect than C9, and both a significantly greater effect than C6. These differential reactions to the three diacids parallel previously reported effects on cell kinetics and viability. The changes could be due to a prime effect on the cell membrane, or they might reflect phases of the cell cycle directed by action of the diacids on the nucleus; this latter seems unlikely. An effect on the cytoskeleton is possibly involved.