Overexpression of a novel superoxide-producing enzyme, NADPH oxidase 1, in adenoma and well differentiated adenocarcinoma of the human colon

Cancer Lett. 2005 Apr 18;221(1):97-104. doi: 10.1016/j.canlet.2004.08.031.


A superoxide-producing enzyme, NADPH oxidase 1 (Nox1), dominantly expressed in the colon, is implicated in the pathogenesis of colon cancer. Immunohistochemistry showed that Nox1 was constitutively expressed in surface mucous cells. Adenomas and well differentiated adenocarcinomas up-regulated Nox1 expression. Ki-67-negative, well differentiated tumor cells contained abundant Nox1, whereas Ki-67-positive, proliferating cells did not express it. This differentiation-dependent expression in normal as well as tumor tissues suggests distinct roles of Nox1 besides mitogenic function. Nuclear factor (NF)-kappaB was predominantly activated in adenoma and adenocarcinoma cells expressing abundant Nox1, suggesting that Nox1 may stimulate NF-kappaB-dependent antiapoptotic pathways in colon tumors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / enzymology*
  • Adenoma / enzymology*
  • Adult
  • Aged
  • Cell Differentiation
  • Colonic Neoplasms / enzymology*
  • Female
  • Humans
  • Male
  • Middle Aged
  • NADPH Oxidase 1
  • NADPH Oxidases / metabolism*
  • NF-kappa B / metabolism
  • Up-Regulation


  • NF-kappa B
  • NADPH Oxidase 1
  • NADPH Oxidases
  • NOX1 protein, human