[The action of amino acid di[2-haloethyl]hydrazides on DNA synthesis in normal and tumor cells and on the cell cycle kinetics in mice with melanoma B-16].

A comparative study was carried out with two alkylating agents IMB-MM and IMB-97 which are di-(2-halogenoethyl) hydrazides of amino acid derivatives. They have been found to exert a high activity towards wide spectrum of experimental tumours. Both agents caused inhibition of incorporation of 3H-thymidine into DNA of melanoma B16, marrow, intestinal mucosa, spleen and liver cells of mice with tumours. A maximal inhibition of DNA synthesis in all tissues was observed 24 h after the single doses of drugs. However 96 h later this effect was removed excluding the tumour cells. The cytofluorimetric study have shown that IMB-MM, like sarcolysine, caused an accumulation of tumour cells in G2/M phase of cell cycle, while IMB-97 increased accumulation of S-phase cells. The difference in phase sensitivity of tumour cells towards IMB-MM and IMB-97 is due to the differences in aminoacid carriers of di-(2-halogenethyl) hydrazide groups.