title: Expression of matrix metalloproteinase gelatinase A messenger ribonucleic acid in parathyroid carcinomas.
abstract: BACKGROUND
  The incidence of parathyroid cancer in patients with hyperparathyroidism is less than 1%. However, these few cases cause diagnostic problems in the absence of clear-cut invasion of adjacent organs or metastasis. New markers are needed to increase diagnostic accuracy.
  
  
  METHODS
  Thirty-one parathyroid tumors from patients with primary hyperparathyroidism were collected worldwide. Eighteen tumors were classified as unequivocal cancers, whereas 13 tumors were considered equivocal because of a lack of infiltrative growth or evidence of recurrence. Paraffin sections were hybridized with a 35S-labeled riboprobe complementary to gelatinase A mRNA, dipped in photographic emulsion, developed, counterstained, and then evaluated by light- and dark-field microscopy.
  
  
  RESULTS
  Fourteen of the 18 unequivocal parathyroid cancers expressed gelatinase A, as compared with the equivocal tumors, of which only 4 of 13 showed expression. The strongest hybridization signal was seen in stromal cells at the tumor border, most likely fibroblasts and macrophages. No expression was detected in tumor cells.
  
  
  CONCLUSIONS
  Invasive growth of many tumors is facilitated by proteolytic enzymes, such as gelatinase A. The presence of gelatinase A mRNA in parathyroid tumors strengthens the suspicion of malignancy but cannot be used as a definitive marker of malignancy.
authors.affiliation: Department of Molecular Medicine, Karolinska Hospital, Stockholm, Sweden.
authors.forename: F
authors.initials: F
authors.lastname: Farnebo
authors.forename: A
authors.initials: A
authors.lastname: Svensson
authors.forename: N W
authors.initials: NW
authors.lastname: Thompson
authors.forename: M
authors.initials: M
authors.lastname: Bäckdahl
authors.forename: L
authors.initials: L
authors.lastname: Grimelius
authors.forename: C
authors.initials: C
authors.lastname: Larsson
authors.forename: L O
authors.initials: LO
authors.lastname: Farnebo
authors.forename: K
authors.initials: K
authors.lastname: Sandelin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D018076:DNA, Complementary; D005347:Fibroblasts / Q000201:enzymology; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D017403:In Situ Hybridization; D020778:Matrix Metalloproteinase 2 / Q000235:genetics*; D008875:Middle Aged; D010282:Parathyroid Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D012333:RNA, Messenger / Q000032:analysis
chemical_list: D018076:DNA, Complementary; D012333:RNA, Messenger; D020778:Matrix Metalloproteinase 2