[Effect of cobamide coenzyme on the growth of several transplantable tumors in rats and on prolonging the life of rats with grafted Zajdel ascitic tumor].

The effect of the cobamide coenzyme (5,6-dimethylbenzimidazolyl-Co-5'-deoxyadenozylcobamide, DBC) on the growth of some forms of rat tumours and on the prolongation of survival of rats with implanted Zajdela ascites hepatoma was compared with that of cyanocobalamine (5,6-dimethylbenzimidazolyl-Co-cyanocobamide, CN-B12). The effect of DBC was shown to differ from that of CN-B12. DBC did not stimulate the growth of the investigated forms of tumours and prolonged survival of rats with implanted Zajdela ascites hepatoma. The rats displayed cancer resistance when DBC or CN-B12 were injected before implantation of tumours or Zajdela ascites hepatoma.