Prediction of human tumor cell chemosensitivity using the sister chromatid exchange assay.

The sister chromatid exchange (SCE) assay has been used to predict the chemosensitivity to 1,3-bis(2-chloroethyl)-1-nitrosourea of various neoplastic cell subpopulations in eight cell lines derived from human brain tumors. Because the SCE assay is based on analysis of individual cells, data obtained can be plotted as frequency histograms of SCEs per chromosome, and the range of chemosensitivities of cell subpopulations can be identified easily. Results suggest that the SCE assay has predictive value as a clinical assay for drugs for which a strong correlation between cell kill and induction of SCEs has been established.