The Vitamin D Receptor Is a Wnt Effector That Controls Hair Follicle Differentiation and Specifies Tumor Type in Adult Epidermis

The study demonstrated that the Vitamin D Receptor (VDR) was essential as a Wnt effector for hair follicle differentiation and determining tumor type in adult epidermis. Researchers found that VDR activation, in combination with β-catenin, promoted hair follicle-specific gene expression and prevented undifferentiated basal cell carcinomas. VDR−/− mice developed alopecia at 9 weeks, and the absence of VDR led to impaired hair follicle differentiation and basal cell carcinoma-like tumors. The study suggested that VDR and β-catenin interactions are crucial for hair follicle differentiation and may influence skin tumor phenotypes, with potential therapeutic benefits for tumors with abnormal Wnt signaling.