[Cytotoxic action of thiophosphamide on human tumor cells].

The cytotoxic action of thiophosphamide on the cells of 16 human tumor xenografts (lung, breast, colon and stomach carcinomas) was studied. The tumor xenografts placed into diffusion chambers were implanted into intact mice. It was demonstrated that thiophosphamide inhibits the progress of cancer cells to mitosis, reduces the rate of DNA synthesis and accumulation of the cells in mitosis and S-phase. The most pronounced and lasting alterations in cell proliferation were recorded in breast cancer, less significant in carcinoma of the stomach. These findings correlate with the data on the clinical efficacy of thiophosphamide applied to the treatment of these tumors.