The binding of N-acetoxy-N-2-acetylaminofluorene to DNA in native and partially dehistonized chicken erythrocyte chromatin was studied. The amounts of carcinogen bound to DNA were measured, after removal of proteins with phenol, by using the absorption ratio A3os/A260 or by counting the radioactivity of 14C-labeled carcinogen. Measurements of uncovered zones of DNA in chromatin were made by com...

BACKGROUND & OBJECTIVES Our previous study showed that cow ghee relative to soybean oil had a protective effect against carcinogen induced mammary cancer in rats. The objective of this study was to elucidate its biochemical mechanism. METHODS Two groups of 21 day old rats (20 each) were fed for 44 wk diet containing cow ghee or soybean oil (10%). Five animals from each group were sacrificed a...

Abstract Background Local sequence context is known to have an impact on the mutational pattern seen in cancer. The RAS genes and a smoking carcinogen, Benzo[a]pyrene diol epoxide (BPDE), been utilised explore these effects. BPDE form adduct at guanines number of gene sites, KRAS codons 12, 13 14, NRAS codon HRAS 12 14. Results Molecular modelling techniques, along with multivariate analysis, d...

A molecular biological rationale for the linear nonthreshold dose-response pattern for carcinogenesis is presented based on the mutagenic activation of oncogens as the basis of initiation. The approach assumes that the linear nonthreshold dose pattern at very low doses applies only to tissues that are promoted by intrinsic and extrinsic agents other than the one being modeled, and that risk is ...