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

Abstract

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.

• Authors: Mitsutoshi Fukuyama, Kazuhito Rokutan, Toshiaki Sano, Hidenori Miyake, Mitsuo Shimada, Seiki Tashiro
• Journal: Cancer letters (Cancer Lett) Vol. 221 Issue 1 Pg. 97-104 (Apr 18 2005) ISSN: 0304-3835 [Print] Ireland
• PMID: 15797632 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

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

Topics

• 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