Regulation of Melanocyte Stem Cell Behavior by the Niche Microenvironment

The document reviews the regulation of melanocyte stem cells (McSCs) by their niche microenvironment, focusing on the hair follicle as a model. It discusses how various signaling pathways, such as WNT/B-catenin, KITL/KIT, and others, influence McSC responses to genotoxic damages and mechanical injury. The review finds that UVB irradiation causes McSC proliferation and differentiation without leading to hair graying, while mechanical injuries can activate McSCs to aid in epidermal regeneration. Plucking injury is shown to reset the hair cycle and can lead to hyperpigmentation or hair graying depending on the frequency. Crosstalk between McSCs and neighboring cells is crucial for hair regeneration and pigmentation. The document also notes the importance of MC1R signaling in McSC maintenance and melanoma risk, with NOTCH signaling and MITF being essential for McSC maintenance. The potential of McSCs in regenerative medicine for treating hypopigmentation disorders is highlighted, and the research emphasizes the need for a deeper understanding of the McSC regulatory network. The research was supported by the National Natural Science Foundation of China and the Research Grant of Wenzhou Medical University.