Epidermal Stem Cells of the Skin

Abstract

The skin constantly renews itself throughout adult life, and the hair follicle undergoes a perpetual cycle of growth and degeneration. Stem cells (SCs) residing in the epidermis and hair follicle ensure the maintenance of adult skin homeostasis and hair regeneration, but they also participate in the repair of the epidermis after injuries. We summarize here the current knowledge of epidermal SCs of the adult skin. We discuss their fundamental characteristics, the methods recently designed to isolate these cells, the genes preferentially expressed in the multipotent SC niche, and the signaling pathways involved in SC niche formation, SC maintenance, and activation. Finally, we speculate on how the deregulation of these pathways may lead to cancer formation.

Beyond tumorigenesis: cancer stem cells in metastasis

“…Similar to normal stem cells, CSCs can reproduce themselves through the process of self-renewal, which can be studied in serial transplantation assays. Additionally, cancers derived from purified CSCs recapitulate the heterogeneous phenotypes of the parental cancer from [32,47] (ii) c-Kit + Thy1 low Sca1 + Lin - [134,135] Breast (ii) CD24 med CD49f hi [6] (i) CD44 + CD24 -/low ESA + Lin - [33] (ii) CD29 hi CD24 + Lin - [7] Brain (i) CD133 + Lin - [41] (i) CD133 + [34][35][36] Lung (ii) Sca-1 + CD34 + Lin - [5] (ii) Sca-1 + CD34 + Lin - [5] Skin (ii) CD34 + CD71 low α6-integrin high [136] (i) CD20 + [137] Prostate (i) CD133 + a2b1 hi [138] (i) CD44 + α2β1 hi CD133 + [139] www.cell-research.com | Cell Research Feng Li et al npg which they were derived, reflecting the differentiation capacity of CSCs [32,33]. These observations suggest that CSCs contain the complete genetic programs necessary to initiate and sustain tumor growth.…”

Novel In Vitro Culture Condition Improves the Stemness of Human Dermal Stem/Progenitor Cells

“…Adult stem cells have also been found in skin dermis (Amoh et al, 2005;Biernaskie et al, 2009;Blanpain et al, 2006;Driskell et al, 2009;Fernandes et al 2004;Fuchs, 2009;Ohyama et al, 2006;Shim et al, 2012;Toma et al, 2001;. Although some scientists have tried to search for universal dermal stem cell markers on the plasma membrane for easy isolation, specific markers have still not been identified.…”

p63 in epithelial development

“…The epidermis is continuously renewed due to a regulated balance between proliferation and differentiation. The renewal capacity is due to the presence of epidermal stem cells and transient amplifying (TA) cells in the basal layer of the interfollicular epidermis and in the bulge (at least in mouse) of the hair follicle [2]. The concept that the transcription factor p63 is essential for the formation of the epidermis and other stratified epithelia arises from two lines of evidence.…”