SHH and basal cell carcinoma: These include basal cell carcinomas, colorectal cancer, ovarian cancer and small‐cell lung cancer.14, 29, 30, 36 Activation of the Shh signalling pathway has an essential role in controlling self‐renewal and tumour initiation in melanoma.37 In addition, the Shh signalling pathway increases the initial generation and self‐renewal of neural cells.16 To our knowledge, there is no available study as to whether the Shh signalling pathway influences the proliferation, self‐renewal and apoptosis of mSKPs.