[The effect of oxythiamine on tumor growth and certain biochemical and genetic characteristics of normal and tumor cells].

The effect of oxythiamine (400 mg/kg) on chromosomal structure of Ehrlich ascites carcinoma cells (EAC, hyperdiploid strain) and bone marrow cells was studied in intact AF mice. The influence of the antivitamin on the rate of tumor growth was investigated in tumor-bearing mice. Oxythiamine decreased transketolase activity in hepatocytes and tumoral cells and markedly inhibited tumor growth. Amount of chromosomes was unaltered both in tumor cells and in bone marrow cells, which could be manifested as increased content of cells with impairment of chromosomal set calculated per a cell. However, the oxythiamine-induced impairment of chromosomal integrity was less distinct as compared with the effect of such mutagens as urethane and cyclophosphamide; hence, the antivitamin might be used in the courses of combined chemotherapy.