Repression of Benzo[ a ]pyrene Tumorigenesis by Agents Present in Cells Infected or Transformed by Type 12 Adenovirus ∗

Abstract

Summary and Conclusions

A significant retardation in the appearance and growth of benzo[a]pyrene-induced tumors was noted in hamsters pretreated with unpurified type 12 adenovirus (active or heated-inactivated) and also with sonicated virus-free Ad12-transformed hamster embryo cells (HET). Maternal immunization with active Ad12 or sonicated HET similarly retarded the development of benzypyrene-induced tumors in the mature offspring, when the first of three injections of the chemical was given at the age of 3 weeks.