Antibiotics produced by Streptomyces olivaceus 142. III. Influence of antibiotic Wr 142 FPG on development of transplantable tumors in mice.

The action of two preparations (I and II) of antibiotic Wr 142 FPG on development of Ehrlich carcinoma, Nemeth-Kellner lymphoma and leukemias L 1210 and P 388 was studied. Preparation I injected s.c. daily during 14 days in doses of 10 mg/kg (1/25 LD50) inhibited growth of Ehrlich carcinoma and Nemeth-Kellner lymphoma subcutaneous tumors in R 3 mice by about 70%. The same preparation in a single i.p. injection (10 mg/kg) in FDF1 mice distinctly prolonged survival of mice inoculated with L 1210 leukemia, but was without effect on P 388 leukemia. Preparation II inhibited growth of solid tumors in doses as low as 0.1-0.2 mg/kg (about 65% inhibition), but in the same doses was ineffective against leukemias L 1210 and P 388 in CDF1 mice.