Type I interferons: key players in normal skin and select cutaneous malignancies.

Interferons (IFNs) are a family of naturally existing glycoproteins known for their antiviral activity and their ability to influence the behavior of normal and transformed cell types. Type I Interferons include IFN- α and IFN- β . Currently, IFN- α has numerous approved antitumor applications, including malignant melanoma, in which IFN- α has been shown to increase relapse free survival. Moreover, IFN- α has been successfully used in the intralesional treatment of cutaneous squamous cell carcinoma (SCC) and basal cell carcinoma (BCC). In spite of these promising clinical results; however, there exists a paucity of knowledge on the precise anti-tumor action of IFN- α / β at the cellular and molecular levels in cutaneous malignancies such as SCC, BCC, and melanoma. This review summarizes current knowledge on the extent to which Type I IFN influences proliferation, apoptosis, angiogenesis, and immune function in normal skin, cutaneous SCC, BCC, and melanoma.