Colorectal Cancer
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Sep 21, 2006; 12(35): 5644-5650
Published online Sep 21, 2006. doi: 10.3748/wjg.v12.i35.5644
Hemoglobin induces colon cancer cell proliferation by release of reactive oxygen species
Ryung-Ah Lee, Hyun-Ah Kim, Bo-Young Kang, Kwang-Ho Kim
Ryung-Ah Lee, Ewha Medical Institute, Department of Surgery, College of Medicine, Ewha Womans University, Seoul, Korea
Hyun-Ah Kim, Kwang-Ho Kim, Department of Surgery, College of Medicine, Ewha Womans University, Seoul, Korea
Bo-Young Kang, Ewha Medical Institute, Ewha Womans University, Seoul, Korea
Author contributions: All authors contributed equally to the work.
Supported by 2003 the Aventis-Cheiljedang Grant Award offered from Korean society of Coloproctology, No: 2003-005
Correspondence to: Ryung-Ah Lee MD, PhD, Department of Surgery, Ewha Womans University Mokdong Hospital, 158-710, 911-1, Mokdong, Yangcheonku, Seoul, Korea.
Telephone: +82-2-26502659 Fax: +82-2-26447984
Received: March 29, 2006
Revised: April 9, 2006
Accepted: April 16, 2006
Published online: September 21, 2006

AIM: To study whether hemoglobin could amplify colon cancer cell proliferation via reactive oxygen species (ROS) production.

METHODS: Colon cancer cell line HT-29 was grown in the conventional method using RPMI1640 media. The viability of the cells was measured using the colorimetric MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide] assay after adding hemoglobin. We determined reactive oxygen species levels to be indicators of oxidative stress in HT 29 cell lines with and without hemoglobin and/or 5-fluorouracil (5-FU), 5’-deoxy-5-fluorouridine (5-DFUR) using fluorometric dichlorofluorescin diacetate (DCFH-DA) assay.

RESULTS: Cellular proliferation was increased with hemoglobin in a concentration-dependent manner. A significant increment on ROS levels was found in HT 29 cells following hemoglobin incubation. The cytotoxic effects of 5-FU and 5-DFUR were significantly blunted by administration of hemoglobin. There was a slight increase of peroxiredoxin 1, superoxide dismutase 1 concentration according to different hemoglobin concentrations.

CONCLUSION: Hemoglobin has a cellular proliferative effect on HT-29 colon cancer cell line by production of ROS. Also, hemoglobin abates cytotoxic effects of chemotherapeutic agents such as 5-FU and 5-DFUR.

Keywords: Colon cancer, Hemoglobin, Reactive oxygen species