PTCH1 and diabetes mellitus: The Hh signaling pathway is one of most important signaling pathways regulating the development, repair, and maintenance of stem cells in the skin and appendages.[20, 34, 35, 36] To investigate whether the impaired proliferation of dermal fibroblasts and vascularization of endothelial cells in DM are associated with downregulated Hh signaling, we initially evaluated the expression of GLI1, CCND1, and PTCH1, which are reader‐outs of Hh signaling pathways, in diabetic wounds.