Differential effects of cisplatin on the expression of chimeric marker genes in CV-1 cells

The effect of the antitumor drug cisplatin on marker gene expression in CV-1 monkey cells was measured. When non-replicating test genes were introduced by transient transfection, there was strong differential inhibition caused by the drug. Expression of certain genes was relatively insensitive, but expression of others was inhibited as strongly as was DNA replication. Stronger promoters led to stronger inhibition. This selective inhibition was not observed with the pharmacologically inactive isomer transplatin. The results raise the possibility that inhibition of strongly expressed genes by cisplatin may contribute to the antitumor activity of the drug.