Hemoglobin induces colon cancer cell proliferation by release of reactive oxygen species.
OBJECTIVE
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.


CONCLUSIONS
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.
Lee
Ryung-Ah
RA
Department of Surgery, Ewha Womans University Mokdong Hospital, 158-710, 911-1, Mokdong, Yangcheonku, Seoul, Korea. ralee@ewha.ac.kr
Kim
Hyun-Ah
HA
Kang
Bo-Young
BY
Kim
Kwang-Ho
KH
D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D000069287:Capecitabine; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D003110:Colonic Neoplasms / Q000378:metabolism* / Q000473:pathology*; D003841:Deoxycytidine / Q000031:analogs & derivatives / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005472:Fluorouracil / Q000494:pharmacology; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D019073:HT29 Cells; D006454:Hemoglobins / Q000502:physiology*; D006801:Humans; D018384:Oxidative Stress; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism; D054464:Peroxiredoxins; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism
D000964:Antimetabolites, Antineoplastic; D006454:Hemoglobins; D017382:Reactive Oxygen Species; D003841:Deoxycytidine; D000069287:Capecitabine; D010544:Peroxidases; C515940:PRDX1 protein, human; D054464:Peroxiredoxins; D013482:Superoxide Dismutase; D005472:Fluorouracil