title: Overexpression of 5-lipoxygenase in sporadic colonic adenomas and a possible new aspect of colon carcinogenesis.
abstract: OBJECTIVE
  We aimed to study the intracellular expression of 5-lipoxygenase (5-LOX), the primary competitor with cyclooxygenase-2 in arachidonic acid metabolism, as inflammatory enzymes may be involved in blocking apoptosis and promoting cancer growth by changing arachidonic acid metabolism within cells. Our purpose was to investigate the possible connection between 5-LOX expression and colon carcinogenesis by characterizing 5-LOX expression in histologically different colonic adenomas, determining the relationship between high expression of 5-LOX and various conventional clinicopathological features of adenomas, and finally characterizing the histological localization of cells with 5-LOX overexpression.
  
  
  METHODS
  A total of 111 patients were examined and 120 histologically different colonic adenomas analyzed (including four cases of intramucosal adenocarcinoma in a polyp). Immunohistochemical staining with polyclonal anti-5-LOX antibodies was performed.
  
  
  RESULTS
  There was a significant correlation between high 5-LOX expression and patient age, increased polyp size, high grade of intraepithelial neoplasia, villous and tubulovillous adenoma, and histological epithelial localization.
  
  
  CONCLUSIONS
  We observed a strong positive correlation between 5-LOX overexpression and the appearance of typical high-risk factors for malignant transformation in adenomatous polyps. The results support the role of 5-LOX in early stages of colon carcinogenesis.
authors.affiliation: Department of Gastroenterology, Pomeranian Medical University, Szczecin, Poland. newdodo@poczta.onet.pl
authors.forename: Michał P
authors.initials: MP
authors.lastname: Wasilewicz
authors.forename: Blanka
authors.initials: B
authors.lastname: Kołodziej
authors.forename: Teresa
authors.initials: T
authors.lastname: Bojułko
authors.forename: Mariusz
authors.initials: M
authors.lastname: Kaczmarczyk
authors.forename: Violetta
authors.initials: V
authors.lastname: Sulzyc-Bielicka
authors.forename: Dariusz
authors.initials: D
authors.lastname: Bielicki
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Ciepiela
mesh_terms: D000236:Adenoma / Q000201:enzymology* / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001094:Arachidonate 5-Lipoxygenase / Q000378:metabolism*; D002278:Carcinoma in Situ / Q000201:enzymology / Q000473:pathology; D003110:Colonic Neoplasms / Q000201:enzymology* / Q000473:pathology*; D003111:Colonic Polyps / Q000201:enzymology / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011230:Precancerous Conditions / Q000201:enzymology* / Q000473:pathology*
chemical_list: D001094:Arachidonate 5-Lipoxygenase