Colorectal Cancer
Copyright ©2005 Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 21, 2005; 11(15): 2244-2248
Published online Apr 21, 2005. doi: 10.3748/wjg.v11.i15.2244
Ornithine decarboxylase gene is overexpressed in colorectal carcinoma
Hai-Yan Hu, Xian-Xi Liu, Chun-Ying Jiang, Yi Lu, Shi-Lian Liu, Ji-Feng Bian, Xiao-Ming Wang, Zhao Geng, Yan Zhang, Bing Zhang
Hai-Yan Hu, Xian-Xi Liu, Yi Lu, Shi-Lian Liu, Ji-Feng Bian, Xiao-Ming Wang, Zhao Geng, Yan Zhang, Bing Zhang, Experimental Center of Medical Molecular Biology, Biochemistry and Molecular Biology Institute, School of Medicine, Shandong University, Jinan 250012, Shandong Province, China
Chun-Ying Jiang, Department of Colo-proctology, The Affiliated Hospital of Shandong University of Tradition Chinese Medicine, Jinan 250012, Shandong Province, China
Author contributions: All authors contributed equally to the work.
Correspondence to: Xian-Xi Liu, Experimental Center of Medical Molecular Biology, School of Medicine, Shandong University, Jinan 250012, Shandong Province, China. xianxi@sdu.edu.cn
Telephone: +86-531-8382346
Received: May 25, 2004
Revised: May 26, 2004
Accepted: June 18, 2004
Published online: April 21, 2005
Abstract

AIM: To investigate the ornithine decarboxylase (ODC) gene expression in colorectal carcinoma, ODC mRNA was assayed by RT-PCR and ODC protein was detected by a monoclonal antibody against fusion of human colon ODC prepared by hybridoma technology.

METHODS: Total RNA was extracted from human colorectal cancer tissues and their normal counterpart tissues. ODC mRNA levels were examined by RT-PCR. ODC genes amplified from RT-PCR were cloned into a prokaryotic vector pQE-30. The expressed proteins were purified by chromatography. Anti-ODC mAb was prepared with classical hybridoma techniques and used to determine the ODC expression in colon cancer tissues by immunohistochemical and Western blotting assay.

RESULTS: A cell line, which could steadily secrete anti-ODC mAb, was selected through subcloning four times. Western blotting reconfirmed the mAb and ELISA showed that its subtype was IgG2a. RT-PCR showed that the ODC mRNA level increased greatly in colon cancer tissues (P<0.01). Immunohistochemical staining showed that colorectal carcinoma cells expressed a significantly higher level of ODC than normal colorectal mucosa (98.6±1.03% vs 5.26±5%, P<0.01).

CONCLUSION: ODC gene overexpression is significantly related to human colorectal carcinoma. ODC gene expression may be a marker for the gene diagnosis and therapy of colorectal carcinoma.

Keywords: Ornithine decarboxylase; RT-PCR; Colorectal Cancer