The response in vitro, of continuous cultures of human lymphoblasts (CCRF-CEM cells) to chemotherapeutic agents

Abstract

A series of nineteen chemotherapeutic agents and one metabolite has been studied for inhibitory activity in continuous suspension cultures of human leukemic lymphoblasts (CCRF-CEM cells), and the resulting ID 5o data compared with the ID 50 data derived from previous studies with other kinds of mammalian cells in monolayer cultures. As adjudged by comparison of ID 50 data interpolated from dose: response curves in the usual manner, only two chemotherapeutic agents exhibited a greater degree of inhibitory activity for CCRF-CEM cells, and there was little evidence that CCRF-CEM cells are preferentially sensitive to those chemotherapeutic agents useful in the chemotherapy of human leukemia. The difficulties intrinsic in the interpretation of such comparative bioassay data are discussed. The CCRF-CEM cells were exquisitely sensitive to inhibition by exogenous thymidine, from which some chemotherapeutic advantage may derive. The utility of human leukemic cells in an appropriate bioassay system may reside in the detection of other agents to which such cells may be unusually or uniquely sensitive.