[Sensitivity to chemotherapeutic preparations of anthracycline-resistant strains of murine leukemia P388].

P388 leukemia strains resistant to rubomycin and ruboxylnitroxyl derivative of rubomycin were studied for their drug sensitivity. The resistant strains exhibited cross resistance to anthracycline antibiotics, vinca alkaloids, actinomycin D, colchicine. The rubomycin-resistant strain gained significantly higher sensitivity (in comparison with the parent strain and the ruboxyl-resistant strain) to six drugs: cisplatin, sarcolisin, dopan, thiophosphamide, degranol, 6-mercaptopurine. The karyotype of the ruboxyl-resistant cells was characterized by the presence of chromosome with homogeneously straining region (HSR). The alteration of the HSR-location was accompanied by the increase of chemotherapeutical sensitivity of the ruboxylresistant strain to the alkylating agents.