The relationship between skin color and skin cancer is well established—lesser melanin content in ones skin, greater is the risk for developing skin cancer.

A new article published in The Yale Journal of Biology and Medicine aimed to summarize the current understanding of the cutaneous pigmentary system and trace melanin from its synthesis in the pigment cell melanosomes through its transfer to keratinocytes; present new methods for reducing melanin content in hyper-pigmented areas of skin such as solar lentigenes, melasma and post-inflammatory hyperpigmentation; and to present evidence that at least one mechanism for the development of metastatic melanoma and other solid tumors is fusion and hybridization of leucocytes – such as, macrophages with primary tumor cells.

The authors stated that hybrid cells express both, the chemotactic motility of the leucocyte and the de-regulated cell division of the tumor cell, causing the cells to migrate to lymph nodes, distant organs and tissues. Fusion and hybridization of phagocytes, such as, macrophages with cancer cells creates metastatic cells. One of the mechanisms for metastasis is that, metastatic cancer cells exhibit many macrophage traits.

This information opens many potential targets for the development of new therapies, for example – inhibition of the fusion process itself regarding events such as membrane attachment and heterokaryon formation; inhibition of the hybridization processes involving integration of parental fusion partner genes into hybrid genomes; and prevention of post-hybridization events involving activation of genes that control cell migration, chemotaxis, intravasation, extravasation, migration to lymph nodes and distant metastases.

Source: The Yale Journal of Biology and Medicine. 2020 Mar 27;93(1):69-80.