Cytotoxic effect of β-carotene in vitro is dependent on serum concentration and source

• Published in: Cancer letters Vol. 106; no. 1; pp. 133 - 138
• Main Authors: Peram, Venkatasiva, Iftikhar, Shaukat, Lietz, Helen, Mobarhan, Sohrab, Frommel, Thomas O.
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 23-08-1996; Elsevier
• Subjects: Antineoplastic agents; Antineoplastic Agents - toxicity; beta Carotene - administration & dosage; beta Carotene - blood; beta Carotene - toxicity; Biological and medical sciences; Cell Survival - drug effects; Chemoprevention; Colon cancer; Colonic Neoplasms; Culture Media; Food, Fortified; Furans; General aspects; Humans; Medical sciences; Micronutrients; Pharmacology. Drug treatments; Time Factors; Tumor Cells, Cultured; β-Carotene; Micronutrients; Colon cancer; Chemoprevention; β-Carotene; Antineoplastic agent; Human; Concentration factor; Cytotoxicity; Supplemented diet; Malignant tumor; In vitro; Colonic disease; Micronutrient; Established cell line; Digestive diseases; Intestinal disease; Serum; Colon; Supplementation; High dose; Tumor cell
• ISSN: 0304-3835; 1872-7980
• DOI: 10.1016/0304-3835(96)04317-0

In a previous study we reported that β-carotene solubilized in tetrahydrofuran (THF) is toxic for human colonic tumor cells in vitro using media containing 10% fetal calf serum (FCS). Cytotoxicity was evident using β-carotene concentrations that are achieved in human serum as a result of supplementation with 30 mg β-carotene/day. In an attempt to determine the mechanism for this toxicity we investigated the effect of β-carotene when present in human serum as a result of dietary supplementation. This effect was compared to that observed for cells incubated in THF-solubilized β-carotene. The results indicate that human serum from subjects with a high concentration of β-carotene is not cytotoxic. Subsequent analysis revealed that in contrast to the results using FCS, THF-solubilized β-carotene is not cytotoxic in the presence of human serum. In addition, the effect observed with FCS is blunted with increasing FCS concentration from ⩾90% cytotoxicity using 10% FCS to 36% using 100% FCS. The difference in results obtained using FCS and human serum may be due to a serum component that is relatively lacking in FCS as compared to human serum.