Abstract
A comparative study of selective cytotoxicity between non-transformed and SV40-transformed cells has been undertaken in combination with antitumor agents having different mechanisms of action. The selective in vitro cytotoxicity assay (N/T assay) measured the decrease in cell proliferation under the microscope. SV40-transformed cells had higher sensitivity than non-transformed cells against these antitumor agents at low concentration; but an apparent dissimilar pattern of sensitivity was observed in some antimetabolites, such as cytosine arabinoside, 6-mercaptopurine, 5-fluorouracil, and in some inhibitors of energy-transfer. The results can be interpreted in terms of a possible difference in cytotoxicity between non-transformed and SV40-transformed cell lines. The N/T assay may be considered a convenient system for evaluating selective cytotoxicity for in vitro-in vivo comparisons.
