Differential Expression of Selected Genes Involved in Pheomelanogenesis in Melanotic and Amelanotic Human Melanoma Cells

Background/Objectives: Melanin synthesis in normal skin involves numerous genes, and disturbances in their function may increase the risk of malignant transformation of mela-nocytes. Genes regulating pheomelanin synthesis are of particular interest, as this pig-ment may actively contribute to cutaneous malignant melanoma pathogenesis. Normal melanocytes differ in pheomelanin content depending on skin phototype, which affects susceptibility to neoplastic transformation. However, the influence of pheomelanin on melanoma cell characteristics has not yet been fully elucidated. Methods: To gain further insight, we examined the expression of pheomelanogenesis-related genes in two mela-noma cell lines of distinct pigmentation status, amelanotic C32 and melanotic G361. We analysed the expression of 44 genes involved in melanocyte development and pigmenta-tion, classifying them by their direct or indirect role in pheomelanogenesis. Gene expres-sion levels were quantified using real-time reverse transcription polymerase chain reac-tion (real-time RT-PCR). Results: Our results show that melanoma cells with distinct pig-mentation phenotypes exhibit heterogeneous expression patterns. For instance, G361 cells expressed higher levels of POMC, MC1R, TYRP1, TYR, SLC45A2, and CTNS, while SLC7A11 and DCT/TYRP2 were more abundant in C32 cells. Conclusions: These findings suggest that differences in the expression of pheomelanin-related genes may contribute to melanoma cell diversity and could play a role in defining tumour behaviour. Evaluation of melanogenesis-related gene expression and, in particular, the activity of pheomelano-genesis may therefore represent a valuable approach for melanoma classification, prog-nosis, and therapeutic decision-making.