Melanogenesis and DNA damage following photodynamic therapy in melanoma with two meso-substituted porphyrins

PDT induced high levels of DNA damage, cytoskeleton alterations and enhanced pigmentogenesis. THOPP mediated PDT was the most efficient. The melanogenesis stimulated by PDT was directly correlated to the PDT induced cellular damage and provided no protection against therapy. Thus, PDT induced melanogenesis combined with severe DNA damage was able to overcome the mechanisms of resistance and increased the efficiency of PDT in WM35 melanoma cells. These results are encouraging for a possible use of PDT, as an adjuvant therapy in lightly pigmented melanomas.