[Sensitivity tests of malignant tumours against cytostatic agents in vitro and in vivo/studies on the mouse sarcoma 180 (author's transl)].

The effects of ten different substances on the mouse sarcoma 180 have been compared using in vivo and in vitro test systems. The size of the tumours was taken as a measure of the success of the therapy in animal experiments. The in vitro effects were estimated by measuring the incorporation of radioactively labelled uridine in tumour cell suspensions from solid tumours, in ascites tumours and in tissue culture. Similar results were obtained using all three in vitro test systems. Four substances (daunomycin, fluoruracil, actinomycin D, adriamycin) exhibited activity both in vivo and in vitro, whereas five substances (cytosinarabinoside, methotrexate, ibenzmethyzin, triaziquone, bleomycin) showed no activity in any of the test systems used. With podophyllic acid ethyl hydrazide, however, no correlation between in vivo and in vitro effects was observed. Studies on the influence of the cytostatic agents on the rate of transport of uridine into the cells showed that podophyllic acid ethyl hydrazide strongly reduced the permeability of the cells to radioactive uridine.