title: [Cyclo-oxygenase-2 and p53 immunoreactivity in superficial early colorectal carcinoma].
abstract: OBJECTIVE
  De novo colorectal carcinoma shows more aggressive behavior including submucosal invasiveness. Both p53 and cyclo-oxygenase-2 (COX-2) have been shown to be involved in colon carcinogenesis, progression from adenoma to carcinoma, and submucosal invasion by tumor. We performed this study to evaluate the expression of p53 and COX-2 protein in de novo carcinoma, compared with ex-adenoma carcinoma.
  
  
  METHODS
  Twenty three flat adenomas, 19 ex-adenoma carcinomas, 6 de novo carcinomas were included in this study. The expression of p53, COX-2 and Ki-67 were examined immunohistochemically.
  
  
  RESULTS
  Both ex- adenoma carcinomas and de novo carcinomas showed similar size and shape. Positive staining for p53 was detected in 3 of 23 (13%) flat adenomas, in 11 of 19 (57.8%) ex-adenoma carcinomas (p < 0.05), and in 1 of 6 (16.6%) de novo carcinomas. Increased numbers of COX-2 positive tumor cells were observed in 1 of 23 (4.3%) flat adenomas, in 2 of 19 (10.5%) ex-adenoma carcinomas, and in 3 of 6 (50%) de novo carcinomas. COX-2 positive expression showed increased tendency in de novo carcinoma (p = 0.073). There was no correlation between COX-2, p53, and Ki-67 expression.
  
  
  CONCLUSIONS
  De novo carcinoma shows increased tendency of COX-2 expression, but decreased p53 expression when compared to ex-adenoma carcinoma. These immunohistochemical findings are in accordance with the fact that de novo carcinoma has no preceding adenoma, with more frequent submucosal invasion despite the small lesion size.
authors.affiliation: Department of Internal Medicine, Seoul Paik Hospital, Inje University College of Medicine, Jung-gu, Seoul, Korea. yousunk69@korea.com
authors.forename: You Sun
authors.initials: YS
authors.lastname: Kim
authors.forename: So Dug
authors.initials: SD
authors.lastname: Lim
authors.forename: Jin Kwang
authors.initials: JK
authors.lastname: Lee
authors.forename: Seong Eun
authors.initials: SE
authors.lastname: Kim
authors.forename: Soo Hyung
authors.initials: SH
authors.lastname: Ryu
authors.forename: Jung Whan
authors.initials: JW
authors.lastname: Lee
authors.forename: Jeong Seop
authors.initials: JS
authors.lastname: Moon
mesh_terms: D000236:Adenoma / Q000737:chemistry / Q000473:pathology; D014408:Biomarkers, Tumor / Q000032:analysis; D002277:Carcinoma / Q000737:chemistry / Q000473:pathology; D015179:Colorectal Neoplasms / Q000737:chemistry / Q000473:pathology*; D051546:Cyclooxygenase 2 / Q000032:analysis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis; D008297:Male; D008875:Middle Aged; D016159:Tumor Suppressor Protein p53 / Q000032:analysis*
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D016159:Tumor Suppressor Protein p53; D051546:Cyclooxygenase 2