Effect of Thymidine on the Sensitivity of Cultured Mouse Tumor Cells to 1-ß-D-ArabinofuranosyIcytosine

Abstract

Assays of thirteen cell lines, derived from mouse lymphomas, myelomas, myeloid tumors, and a mastocytoma, for sensitivity to growth inhibition by 1-ß-D-arabinofuranosyl- (ara-C) revealed a spectrum between the most and least sensitive which differed 100-fold from each other. An inverse correlation between sensitivity and cellular deoxy-cytidine 5’-triphosphate (dCTP) content was found, and this suggested that sensitivity of cells might be increased if the dCTP content was lowered during cell exposure to ara-C. Previous work has shown that thymidine treatment of cells lowers their dCTP content, and the effect of thymidine on the sensitivity of six of the cell lines to ara-C was therefore meas..