Cytotoxicity of Ascorbic Acid in a Human Colorectal Adenocarcinoma Cell Line (WiDr): In Vitro and In Vivo Studies

Abstract

Vitamin C, available in its reduced form (ascorbic acid; AA) and in its oxidized form (dehydroascorbic acid; DHA), may act in physiological conditions as an antioxidant or pro-oxidant. The aim of this study is to evaluate the cytotoxic effects of pharmacological doses of AA in a human colorectal adenocarcinoma cell line (WiDr) in vitro, through spectrophotometry, clonogenic assays and flow cytometry, and in vivo with xenotransplanted Balb/c nu/nu mice. The results show that the reduced form of vitamin C induces an anti-proliferative and cytotoxic effect in adenocarcinoma colorectal cells under study. The results obtained in vivo after treatment with AA showed a large reduction in the rate of tumor growth. Such understanding can guide decisions about which colorectal cancer patients might potentially benefit from vitamin C pharmacologic therapy.

ACKNOWLEDGMENTS

The authors would like to thank CIMAGO (Center of Investigation in Environment, Genetics and Oncobiology) and Faculty of Medicine of the University of Coimbra for all the support given to this work.

The first and second authors contributed equally to this work.