Epidermal cell renewal

Epidermal cell renewal is the lifelong process by which the epidermis, the skin’s outermost layer, maintains itself through cycles of stem cell division, differentiation, and eventual shedding of terminally differentiated keratinocytes. Stem cells in the basal layer divide to produce transit-amplifying cells, which progressively differentiate as they migrate toward the surface, ultimately forming the protective barrier of dead, keratinized squames that are routinely shed and replaced. This process is regulated by multiple signaling pathways, including Wnt, Hedgehog, Notch, BMP, EGF, and integrins. Disruption of renewal rates or signaling fidelity can result in various skin diseases, impaired healing, or tumorigenesis. It is not a single molecule or therapeutic target, but rather a critical, regulated biological process essential for skin integrity and function.

Other names

Skin cell turnoverEpidermal cell turnoverSkin cell regenerationKeratinocyte renewalEpidermal regeneration

Stimulating keratinocyte proliferation and turnover (e.g., retinoids promote basal cell proliferation) Modulating differentiation signals (e.g., via Wnt, Hedgehog, Notch, EGF/BMP pathways) Modifying inflammation or anti-proliferative effects (e.g., corticosteroids)