Basic Research
Copyright ©2005 Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. May 28, 2005; 11(20): 3065-3069
Published online May 28, 2005. doi: 10.3748/wjg.v11.i20.3065
Ornithine decarboxylase, mitogen-activated protein kinase and matrix metalloproteinase-2 expressions in human colon tumors
Takahiro Nemoto, Shunichiro Kubota, Hideyuki Ishida, Nobuo Murata, Daijo Hashimoto
Takahiro Nemoto, Shunichiro Kubota, Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
Hideyuki Ishida, Nobuo Murata, Daijo Hashimoto, Department of Surgery, Saitama Medical Center, Saitama Medical School, 1981 Tsujido-machi, Kamoda, Kawagoe City, Saitama 350-8550, Japan
Shunichiro Kubota, Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan
Author contributions: All authors contributed equally to the work.
Correspondence to: Dr. Shunichiro Kubota, Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan. kubota@idaten.c.u-tokyo.ac.jp
Telephone: +81-3-5454-6869 Fax: +81-3-5454-6869
Received: October 8, 2003
Revised: October 9, 2003
Accepted: January 9, 2004
Published online: May 28, 2005
Abstract

AIM: To investigate the expressions of ornithine decarboxylase (ODC), MMP-2, and Erk, and their relationship in human colon tumors.

METHODS: ODC activity, MMP-2 expression, and mitogen-activated protein (MAP) kinase activity (Erk phosphorylation) were determined in 58 surgically removed human colon tumors and their adjacent normal tissues, using [1-14C]-ornithine as a substrate, ELISA assay, and Western blotting, respectively.

RESULTS: ODC activity, MMP-2 expression, and Erk phosphorylation were significantly elevated in colon tumors, compared to those in adjacent normal tissues. A significant correlation was observed between ODC activities and MMP-2 levels.

CONCLUSION: This is the first report showing a significant correlation between ODC activities and MMP-2 levels in human colon tumors. As MMP-2 is involved in cancer invasion and metastasis, and colon cancer overexpresses ODC, suppression of ODC expression may be a rational approach to treat colon cancer which overexpresses ODC.

Keywords: Ornithine decarboxylase; Human colon tumors; mitogen activated protein