FKBP4 and melanoma: Several pieces of evidence suggest that FKBP51 acquires a pro-oncogenic potential [26,27]; for example, it positively regulates melanoma stemness and metastatic potential [28], it is thought to be a key factor in the progression and chemotherapeutic response of pancreatic adenocarcinoma [29], and it is closely related to acute lymphoblastic leukemia and several variants of breast, ovary, and lung tumor pathologies [27].