title: Expression of metallothionein and Ki-67 antigen in GISTs of different grade of malignancy.
abstract: BACKGROUND
  Metallothioneins (MTs) are low molecular weight proteins (6-7 kDa), which have been shown to regulate zinc ion homeostasis. MTs exert anti-apoptotic and pro-proliferative effect on cancer cells. Overexpression of MT-I and MT-II isoforms has been noted in many malignant tumors, but the role of their expression in gastrointestinal stromal tumors (GISTs) remains unclear.
  
  
  OBJECTIVE
  The aim of the study was to examine the relationship between expression of MT-I/II and K-67 proliferation antigen in a subset of GISTs presenting differential grade of malignancy.
  
  
  METHODS
  The study was conducted using immunohistochemical methods on archival paraffin sections of 34 cases of GISTs. Of those, 17 tumors were classified as benign (GISTB) and 17 tumors as malignant (GISTM).
  
  
  RESULTS
  The GISTM cases demonstrated higher MT-I/II expression as compared to the GISTB cases, but not significantly higher (p = 0.08). The GISTM tumors showed significantly higher expression of Ki-67 antigen than the GISTB cases (p = 0.01). MT-I/II and Ki-67 expression positively correlated in GISTBs (r = 0.48, p = 0.0463), but not in GISTMs.
  
  
  CONCLUSIONS
  The results of this study may point to a potential role of MT-I/II in the proliferation of GIST cells and disease progression.
authors.affiliation: Department of Histology and Embryology, Wroclaw Medical University, Wrocław, Poland.
authors.forename: Bartosz
authors.initials: B
authors.lastname: Puła
authors.forename: Marta
authors.initials: M
authors.lastname: Strutyńska-Karpińska
authors.forename: Alicja
authors.initials: A
authors.lastname: Markowska-Woyciechowska
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Jethon
authors.forename: Dariusz
authors.initials: D
authors.lastname: Wołowiec
authors.forename: Janusz
authors.initials: J
authors.lastname: Ryś
authors.forename: Marzena
authors.initials: M
authors.lastname: Podhorska-Okołów
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Grabowski
authors.forename: Piotr
authors.initials: P
authors.lastname: Dzięgiel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D049109:Cell Proliferation; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000737:chemistry* / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis*; D008297:Male; D008668:Metallothionein / Q000032:analysis*; D008875:Middle Aged; D060787:Neoplasm Grading; D020033:Protein Isoforms
chemical_list: D019394:Ki-67 Antigen; C491053:MT2A protein, human; D020033:Protein Isoforms; D008668:Metallothionein