The mutagenic and carcinogenic properties of three second generation antitumour platinum compounds: a comparison with cisplatin

The cytotoxicity, mutagenicity and transforming potentials of three second generation platinum compounds have been investigated in mammalian cells. All the compounds showed positive response in two assay systems in Chinese hamster V 79 cells, i.e. measurement of mutation induction at the HGPRT locus and of DNA damage as indicated by sister chromatid exchange frequencies. At equitoxic doses, the compounds in order of decreasing mutagenicities were cisplatin, spiroplatin, carboplatin and iproplatin. The BHK transformation assay reflected a similar order in the potential carcinogenicity of the drugs. Cisplatin was highly carcinogenic, followed by spiroplatin. In comparison, carboplatin and iproplatin were potentially weak carcinogens.