Comparison of daunomycin effects on human keratinocytes and melanoma HTB 1410 cells. Image cytometry study.

Interacting melanocytes and keratinocytes in the epidermis create a unique structure in which keratinocytes regulate the growth of melanocytes and the expression of cell surface molecules. The critical role of communication between these cells means that any anti-melanoma drug should be studied in the context of its possible influence on keratinocytes. For that reason, this study focused on comparing the influence of daunomycin on human melanoma cells and on keratinocytes in vitro. The effects were studied by cytochemical methods (TUNEL, FITC-Annexin V labelling, endocytosis activity assay, measurements of DNA content) and morphological methods (measurements of cell surface area, perimeter, extension, dispersion and elongation) to verify the hypothesis of differential response. The results of our research demonstrate that keratinocytes are less susceptible than melanoma cells to daunomycin treatment in vitro. Keratinocytes are also able to resume growth when the drug is removed from the medium, whereas melanoma cells have not demonstrated this capacity. Apoptosis was identified as the mechanism by which the drug exerts its cytostatic effects.