Chemotherapy in experimental brain tumor, part 1: In vitro colorimetric MTT assay

This study concerns the use of the MTT [3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide] colorimetric assay to evaluate the chemosensitivity of the C6 rat glioma cell line to a panel of twelve chemotherapeutic agents. In a previous study of in vitro chemosensitivity of human glioma cell lines, the present authors found a range of sensitivities of the respective cell lines to a panel of chemotherapeutic agents. We then devised an experimental strategy to begin an in vivo evaluation of the correlation between in vitro chemosensitivity and clinical response in an in vivo animal model, such as the model employing the C6 rat glioma cell line. As a step towards utilizing the C6 rat glioma in vivo model, we carried out the present study (Part 1) to determine the correspondence between chemosensitivity to human glioma cell lines and the rat C6 glioma cell line. If a correspondence were to be found, this would enable experimental use of the C6 tumor model for in vivo testing of chemotherapeutic agents. As reported in this paper (Part 1), a correspondence was found, suggesting that the C6 rat glioma represents a suitabe model of human glioma for chemotherapeutic studies. This finding served as a basis for proceeding with an in vivo study of chemotherapeutic efficacy which is the subject of a companion report.