PTCH1 and skin basal cell carcinoma: In another study, the expression profile of HH-signaling-related molecules, GLI1, GLI2, PTCH1, PTCH2, SHH, and SMO in BCC and various other cutaneous tumors were examined by real-time PCR analysis and demonstrated that BCC showed remarkably enhanced mRNA expression of all HH molecules, except SMO, compared to other skin tumors [35].