Comparative Analysis of Bioactivity of the Russian-Made Antitumor Substances of the Nitrosourea Group.

We performed an in vivo comparative study of activity of three substances of the nitrosourea group produced in Russia. All substances demonstrated high antitumor activity against various solid and leukemic tumors. Aranosa significantly enhanced life duration in mice with leukemia (by 65-194%) and inhibited the growth of solid tumors (by 49-99.6%). Lisomustine and ormustine showed higher activity than aranose. Single administration of lisomustine increased life span of mice (by 22-114%) and resulted in cure of all animals in four models: lymphoblastic leukemia L-1210, lymphocytic leukemia P-388, Lewis lung carcinoma, and cervical cancer RShM-5. After ormustine treatment, full recovery was observed only in groups with lymphocytic leukemia P-388 and cervical cancer RShM-5. These findings attest to higher activity of lisomustine in the studied models.

Phenotypic characteristics of lewis lung carcinoma cells.

We studied adhesive properties and physiological activity in vivo of cells from Lewis lung carcinoma and its metastases. These cells differed in tumorogenic activity and metastatic potential in the syngeneic system. In vivo non-metastasizing cells are characterized by a lower content of surface lectins to tetrasaccharides SiaLex [Neu5Aca2-3Galb1-4(Fuca1-3) GlcNAcb] and SiaLea [Neu5Aca2-3Galb1-3(Fuca1-4)GlcNAcb] and trisaccharide HSO3Lex [HSO32-3Galb1-4(Fuca1-3)GlcNAcb] compared to cells forming metastases in the syngeneic system. Metastatic cells with low tumorogenic activity weakly expressed lectins to disaccharide ligands 6-SiaLac [Neu5Aca2-6Galb1-4Glc], 6-HSO3LacNAc, and A-di [GalNAca 1-3Galb] and trisaccharides H-type 1 [Fuca1-2Galb1-3GlcNAc and Lex [Fuca1-3(Galb 1-4)GlcNAc] compared to cells that initiated tumor formation in the syngeneic system (similarly to transplanted tumors). We hypothesized that cell receptors to these carbohydrate determinates are involved in the development and growth of primary tumors, while lectins to SiaLex, SiaLea, and HSO3Lex play a role in the progress of tumor process and metastasizing.

[Effect of unithiol and thymidine on the toxic and therapeutic action of adriamycin]. / Vliianie unitiola i timidina na toksicheskoe i lechebnoe deistvie adriamitsina.

The influence of unithiol and thymidine treatment on the acute toxicity and therapeutic effect of adriamycin in hemoblastosis La was studied in CBA and C57B1 mice. Unithiol and thymidine were shown to markedly decrease the toxicity of different doses of adriamycin which resulted in a lower mortality and longer survival of the animals. When unithiol and thymidine were administered in combination, their antitoxic effect was added. Since unithiol and thymidine administration does not diminish the therapeutic effect of various doses of adriamycin, unithiol may be recommended for clinical use to decrease adriamycin toxicity in cancer patients.