MMP12 and dermatofibrosarcoma protuberans: Because POSTN is abundant in the tumor stroma of MF and dermatofibrosarcoma protuberans (DFSP) (5, 9), and because substantial numbers of CD163+ TAMs have been detected in the POSTN-rich area in the lesional skin of skin tumors (5, 9), the production of MMP1 and MMP12 is prominent in the lesional skin of MF and DFSP.