de Duve Institute, Faculty of Medicine, Université Catholique de Louvain, Brussels, Belgium.
Stem Cells. 2018 Jan;36(1):22-35. doi: 10.1002/stem.2723. Epub 2017 Oct 31.
Mammalian skin and its appendages constitute the integumentary system forming a barrier between the organism and its environment. During development, skin epidermal cells divide rapidly and stratify into a multilayered epithelium, as well as invaginate downward in the underlying mesenchyme to form hair follicles (HFs). In postnatal skin, the interfollicular epidermal (IFE) cells continuously proliferate and differentiate while HFs undergo cycles of regeneration. Epidermal regeneration is fueled by epidermal stem cells (SCs) located in the basal layer of the IFE and the outer layer of the bulge in the HF. Epidermal development and SC behavior are mainly regulated by various extrinsic cues, among which Wnt-dependent signaling pathways play crucial roles. This review not only summarizes the current knowledge of Wnt signaling pathways in the regulation of skin development and governance of SCs during tissue homeostasis, but also discusses the potential crosstalk of Wnt signaling with other pathways involved in these processes. Stem Cells 2018;36:22-35.
哺乳动物的皮肤及其附属物构成了表皮系统，形成了机体与环境之间的屏障。在发育过程中，皮肤表皮细胞迅速分裂并分层形成多层上皮细胞，并向下凹陷到下面的间质中形成毛囊（HFs）。在出生后的皮肤中，毛囊间表皮（IFE）细胞不断增殖和分化，而 HFs 则经历再生周期。表皮的再生由位于 IFE 的基底层和 HFs 的隆起外层的表皮干细胞（SCs）提供动力。表皮发育和 SC 行为主要受各种外在线索的调节，其中 Wnt 依赖性信号通路起着关键作用。本综述不仅总结了 Wnt 信号通路在组织稳态中调节皮肤发育和控制 SC 方面的最新知识，还讨论了 Wnt 信号通路与其他参与这些过程的途径之间的潜在串扰。干细胞 2018;36:22-35。
