HGF/SF Increases Number of Skin Melanocytes but Does Not Alter Quality or Quantity of Follicular Melanogenesis

The study investigated the effects of hepatocyte growth factor/scatter factor (HGF/SF) overexpression on melanization in transgenic mice. It was found that while HGF/SF increased the number of dermal melanocytes, it did not alter the type or quantity of melanin produced in the skin or hair. Eumelanin was the only type of melanin detected, and no changes were observed in melanin production or hair cycle-related skin thickness. Additionally, no melanocytes or melanosomes were found in the epidermis, indicating a lack of epidermal UV protection. The study concluded that dermal melanocytes in HGF/SF transgenic mice are susceptible to UVA-induced melanoma due to the interaction with eumelanin.