Carcinoma, Basal Cell/metabolism; Carcinoma, Squamous Cell/metabolism; Nuclear Proteins/metabolism; Proto-Oncogene Proteins/metabolism; Repressor Proteins/metabolism; Skin Neoplasms/metabolism; Skin/metabolism; Biomarkers/metabolism; Carcinoma, Basal Cell/genetics; Carcinoma, Basal Cell/pathology; Carcinoma, Squamous Cell/genetics; Carcinoma, Squamous Cell/pathology; Cell Nucleus/metabolism; Cell Nucleus/pathology; Cytoplasm/metabolism; Cytoplasm/pathology; Endothelium, Vascular/metabolism; Fibroblasts/metabolism; Fistula/genetics; Fistula/metabolism; Fistula/pathology; Humans; Keratinocytes/cytology; Keratinocytes/metabolism; Keratinocytes/pathology; Muscle, Smooth, Vascular/metabolism; Nuclear Proteins/genetics; Polycomb Repressive Complex 1; Proto-Oncogene Proteins/genetics; Psoriasis/genetics; Psoriasis/metabolism; Psoriasis/pathology; RNA, Messenger/metabolism; Repressor Proteins/genetics; Skin/cytology; Skin/pathology; Skin Neoplasms/genetics; Skin Neoplasms/pathology; Skin Ulcer/genetics; Skin Ulcer/metabolism; Skin Ulcer/pathology; Stem Cells/cytology; Stem Cells/metabolism; Stem Cells/pathology