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Updated: Dec 19, 2025
Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Regional Variation in Epidermal Susceptibility to UV-Induced Carcinogenesis Reflects Proliferative Activity of
Edwige Roy1, Ho Yi Wong1, Rehan Villani1
1The University of Queensland Diamantina Institute, The University of Queensland, Brisbane, QLD 4102, Australia.
Abstract:
To better understand the influence of ultraviolet (UV) irradiation on the initial steps of skin carcinogenesis, we examine patches of labeled keratinocytes as a proxy for clones in the interfollicular epidermis (IFE) and measure their size variation upon UVB irradiation. Multicolor lineage tracing reveals that in chronically irradiated skin, patches near hair follicles (HFs) increase in size, whereas those far from follicles do not change. This is explained by proliferation of basal epidermal cells within 60 μm of HF openings. Upon interruption of UVB, patch size near HFs regresses significantly. These anatomical differences in proliferative behavior have significant consequences for the cell of origin of basal cell carcinomas (BCCs). Indeed, a UV-inducible murine BCC model shows that BCC patches are more frequent, larger, and more invasive near HFs. These findings have major implications for the prevention of field cancerization in the epidermis.
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