Colorectal Cancer
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Apr 21, 2006; 12(15): 2341-2344
Published online Apr 21, 2006. doi: 10.3748/wjg.v12.i15.2341
Recombinant hybrid protein, Shiga toxin and granulocyte macrophage colony stimulating factor effectively induce apoptosis of colon cancer cells
Mehryar Habibi Roudkenar, Saeid Bouzari, Yoshikazu Kuwahara, Amaneh Mohammadi Roushandeh, Mana Oloomi, Manabu Fukumoto
Mehryar Habibi Roudkenar, Saeid Bouzari, Mana Oloomi, Molecular Biology Unit, Pasteur Institute of Iran, Pasteur Ave, Tehran 13164, Iran
Yoshikazu Kuwahara, Manabu Fukumoto, Department of Pathology, Institute of Development, Aging and Cancer, Tohoku University, Seiryo-cho 4-1, Aoba-ward, Sendai-city, Miyagi-prefecture, 980-8575, Japan
Amaneh Mohammadi Roushandeh, Department of Anatomy, Medicine Faculty, Medical University of Tehran, Tehran 13164, Iran
Correspondence to: Saeid Bouzari, PhD, Molecular Biology Unit, Pasteur Institute of Iran, Pasteur Ave, Tehran 13164, Iran. saeidbouzari@yahoo.com
Telephone: +98-21-695331120-2221 Fax: +98-21-6465132
Received: September 26, 2005
Revised: October 9, 2005
Accepted: October 10, 2005
Published online: April 21, 2006
Abstract

AIM: To investigate the selective cytotoxic effect of constructed hybrid protein on cells expressing granulocyte macrophage colony stimulating factor (GM-CSF) receptor.

METHODS: HepG2 (human hepatoma) and LS174T (colon carcinoma) were used in this study. The fused gene was induced with 0.02 % of arabinose for 4 h and the expressed protein was detected by Western blotting. The chimeric protein expressed in E.coli was checked for its cytotoxic activity on these cells and apoptosis was measured by comet assay and nuclear staining.

RESULTS: The chimeric protein was found to be cytotoxic to the colon cancer cell line expressing GM-CSFRs, but not to HepG2 lacking these receptors. Maximum activity was observed at the concentration of 40 ng/mL after 24 h incubation. The IC50 was 20  ±  3.5 ng/mL.

CONCLUSION: Selective cytotoxic effect of the hybrid protein on the colon cancer cell line expressing GM-CSF receptors (GM-CSFRs) receptor and apoptosis can be observed in this cell line. The hybrid protein can be considered as a therapeutic agent.

Keywords: Shiga toxin; hGM-CSF; Apoptosis; Colon cancer; Cell lines