title: Epithelial Stem Cells of the Skin Contribute to the Histopathologic Umbrella-like Appearance in Actinic Keratosis.
abstract: Although the histopathologic umbrella-like appearance of the epidermis in actinic keratosis (AK) is well known, its histopathogenesis has remained unknown. The author suggests that the penetration depth of ultraviolet B (UVB) radiation can account for such a histopathologic feature by affecting specific epidermal stem cell pools, as the stem cells in the epidermis and the bulge stem cells and sebocyte stem cells in the mid-dermis reside at different depths.
authors.affiliation: Mihara Dermatology Clinic, Tottori University, 1933-1 Takao, Niimi 718-0003, Japan.
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Mihara
keywords: actinic keratosis; buldge stem cell; epidermal stem cell; sebocyte stem cell; ultraviolet B