title: Cathepsin K expression in melanoma is associated with metastases.
abstract: BACKGROUND
  Melanoma of the skin shows a tendency to metastasize via lymph or blood secreting matrix metalloproteinases and cathepsins, which enable penetration through the dermis. Cathepsin K acts in cytoplasm of atypical melanocytes and completely cleaves internalized collagen.
  
  
  METHODS
  Expression of cathepsin K was analyzed immunohistochemically in 45 melanomas and correlated to morphological and clinical parameters.
  
  
  RESULTS
  During six years follow up, 13 patients developed lymph node metastases and three of them distant metastases. Positive expression of cathepsin K was found in 19 cases. In univariate regression analysis histological type, pagetoid spread, mitotic activity and cathepsin K expression were significantly connected to metastases. Cathepsin K was significantly associated to histologic type, ulceration, pagetoid spread and mitotic rate. In multiple logistic regression adjusted to these variables, cathepsin K was an independent predictor in occurrence of metastases (P=0.015). Median to the occurrence of metastases was 40 months in patients with cathepsin K positive expression and 71 months in patients with cathepsin K negative expression (P<0.001).
  
  
  CONCLUSIONS
  In this preliminary study positive expression of cathepsin K in melanoma of the skin is associated with other unfavorable prognostic factors. We consider cathepsin K expression in primary tumor would significantly precipitate occurrence of metastases.
authors.affiliation: Institute of Emergency Medicine Split, Split, Croatia. slavica.juric01@gmail.com.
authors.forename: Slavica Juric
authors.initials: SJ
authors.lastname: Petricevic
authors.affiliation: Department for pathology, legal medicine and cytology, Clinical Hospital Center Split, Split, Croatia.
authors.forename: Antonia
authors.initials: A
authors.lastname: Pavlovic
authors.affiliation: Department for nuclear medicine, Clinical Hospital Center Split, Split, Croatia.
authors.forename: Vesna
authors.initials: V
authors.lastname: Capkun
authors.affiliation: Department for pathology, legal medicine and cytology, Clinical Hospital Center Split, Split, Croatia.
authors.forename: Kristijan
authors.initials: K
authors.lastname: Becic
authors.affiliation: Department for pathology, legal medicine and cytology, Clinical Hospital Center Split, Split, Croatia.
authors.forename: Merica Glavina
authors.initials: MG
authors.lastname: Durdov
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D056657:Cathepsin K / Q000096:biosynthesis* / Q000235:genetics; D002648:Child; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008544:Melanocytes / Q000378:metabolism; D008545:Melanoma / Q000235:genetics* / Q000473:pathology*; D008875:Middle Aged; D008938:Mitosis; D009362:Neoplasm Metastasis; D011379:Prognosis; D012867:Skin / Q000378:metabolism; D012878:Skin Neoplasms / Q000235:genetics* / Q000473:pathology*; D055815:Young Adult
chemical_list: D056657:Cathepsin K