title: Type 3 deiodinase and solid tumors: an intriguing pair.
abstract: BACKGROUND
  Thyroid hormone (TH) metabolism is mediated by deiodinases, a family of thioredoxin fold-containing enzymes that remove iodide from thyroxine and its derivatives. The coordinated action of deiodinases allows target cells to modulate rapidly their own TH availability in response to different cues. Type 3 deiodinase (D3), the physiological inactivator of TH, is an oncofetal protein whose re-activation in adult tissues has been correlated with hyperproliferative states and with human solid tumors. This suggests a link between deiodinase-mediated TH metabolism and carcinogenesis.
  
  
  METHODS
  D3 is overexpressed in basal cell carcinomas (BCCs) and sustains the proliferation of BCC cells. It exerts a similar function in colon cancer, which suggests that attenuating the TH signal is part of a widespread neoplastic program. Here, recent advances in D3 research, particularly as regards the role of D3 regulation and function in solid tumors are reviewed.
  
  
  CONCLUSIONS
  Given the vast array of TH's physiological and cellular functions, unraveling TH metabolism in cancer biology is a promising challenge for the development of new therapies for human cancer.
authors.affiliation: University of Naples 'Federico II', Department of Clinical Medicine and Surgery , Naples , Italy +39 081 7463780 ; +39 081 7463668 ; domsalva@unina.it.
authors.forename: Monica
authors.initials: M
authors.lastname: Dentice
authors.forename: Dario
authors.initials: D
authors.lastname: Antonini
authors.forename: Domenico
authors.initials: D
authors.lastname: Salvatore
mesh_terms: D049109:Cell Proliferation; D006801:Humans; D007453:Iodide Peroxidase / Q000235:genetics / Q000378:metabolism*; D009369:Neoplasms / Q000201:enzymology* / Q000473:pathology
chemical_list: C117274:iodothyronine deiodinase type III; D007453:Iodide Peroxidase