The other member of the immunophilin family, FKBP51, was shown to be associated with the invasiveness and metastatic potential of melanoma SCs [190,191] and with the enhanced cell migration and invasion in papillary thyroid carcinomas [192], and also with cancer stemness, tumor recurrence, and poor prognosis in oral squamous cell carcinomas [183]. This evidence concerns the gene FKBP4 and oral cavity squamous cell carcinoma.