International Journal of Cell Cloning, Vol 6, 392-403, Copyright © 1988 by AlphaMed Press
Comparison of an antimetabolic assay and an antiproliferative assay, both using 3H-thymidine incorporation, to test drug sensitivity of human tumors
N Zaffaroni, R Silvestrini, E Grignolio, R Villa and C DeMarco
Divisione di Oncologia Sperimentale C, Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy.
Two assays based on the inhibition of 3H-thymidine incorporation into DNA
were used to measure either the antimetabolic or the antiproliferative
effects of anticancer drugs. A direct comparison of the two assays was made
with cell suspensions obtained from 11 ovarian cancers and 22 malignant
melanomas. Drugs with different effects on cell cycle phases were tested by
both assays, for a total of 53 drug comparisons. When the sensitivity
indices specific for each system was used, a significant association (p
less than 0.01) was noted between the two assays. The agreement of both
assays in defining in vitro sensitivity or resistance was 100% for ovarian
cancer. For melanoma, 97% of samples resistant to the antimetabolic assay
were also resistant to the antiproliferative assay; whereas, only 45% of
samples sensitive to the antimetabolic assay were sensitive to the
antiproliferative assay.
