title: The circulating microRNA-221 level in patients with malignant melanoma as a new tumor marker.
abstract: BACKGROUND
  MicroRNA-221 (miR-221) is known to be abnormally expressed in malignant melanoma (MM) cells, and it favors the induction of the malignant phenotype through down-modulation of p27Kip1/CDKN1B and the c-KIT receptor. This suggests that the serum level of miR-221 might increase in patients with MM and thus could be used as a new tumor marker.
  
  
  OBJECTIVE
  To evaluate the possibility that the serum miR-221 level can be a marker of MM.
  
  
  METHODS
  Serum samples were obtained from 94 MM patients and 20 healthy controls. MicroRNAs were purified from serum, and miR-221 levels were measured by quantitative real-time polymerase chain reaction.
  
  
  RESULTS
  Circulating miR-221 was detectable and could be quantified in serum samples. MM patients had significantly higher miR-221 levels than healthy controls. Among the MM patients, the miR-221 levels were significantly increased in patients with stage I-IV MM compared to those with MM in situ, and the levels were correlated with tumor thickness. Moreover, a longitudinal study revealed a tendency for the miR-221 levels to decrease after surgical removal of the primary tumor, and to increase again at recurrence.
  
  
  CONCLUSIONS
  Serum levels of miR-221 were significantly increased in MM patients and may be useful not only for the diagnosis of MM, but also for the differentiating MM in situ from stage I-IV MM, and for evaluating tumor progression and monitoring patients during the follow-up period. In addition, considering that the serum levels of miR-221 were correlated with tumor thickness, miR-221 might also be useful as a prognostic marker for patients with MM.
authors.affiliation: Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto, Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Kanemaru
authors.forename: Satoshi
authors.initials: S
authors.lastname: Fukushima
authors.forename: Junji
authors.initials: J
authors.lastname: Yamashita
authors.forename: Noritoshi
authors.initials: N
authors.lastname: Honda
authors.forename: Rie
authors.initials: R
authors.lastname: Oyama
authors.forename: Asako
authors.initials: A
authors.lastname: Kakimoto
authors.forename: Shinichi
authors.initials: S
authors.lastname: Masuguchi
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Ishihara
authors.forename: Yuji
authors.initials: Y
authors.lastname: Inoue
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Jinnin
authors.forename: Hironobu
authors.initials: H
authors.lastname: Ihn
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008545:Melanoma / Q000097:blood* / Q000175:diagnosis / Q000473:pathology; D035683:MicroRNAs / Q000097:blood*; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012878:Skin Neoplasms / Q000097:blood* / Q000175:diagnosis / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D035683:MicroRNAs; C525709:MIR221, human