GLI2 Is Expressed in Normal Human Epidermis and Basal Cell Carcinoma and Induces GLI1 Expression by Binding to Its Promoter

The study demonstrated that GLI2, a transcription factor, was expressed in normal human epidermis and basal cell carcinoma (BCC), and it directly activated GLI1 expression by binding to its promoter, suggesting a positive feedback loop between GLI1 and GLI2. This interaction was shown to potentiate the Sonic Hedgehog (Shh) signaling pathway, which is crucial for hair follicle morphogenesis and BCC formation. The research used various experimental techniques, including luciferase reporter assays and in situ hybridization, to confirm these findings, indicating that GLI2 played a significant role in skin tumorigenesis and hair follicle development.