RESUMEN
To investigate the possible protective effects of natural agents Nigella sativa [NS], Soybean [SB] and Vitamin C [Vit.C.] as well as chemical agent Aspirin [Asp.] against breast carcinogenesis induced in experimental animals using 9,10 Dimethyl benz [a] 1,2 anthracine [DMBA] as a potent breast.carcinogen. Materials and A single dose of dimethylbenz[a]anthracene [DMBA, 15mg], was administered to rats via intragastric intubation. The animals were divided into six groups [control, DMBA, [DMBA + Aspirin], [DMBA + Vitamin C], [DMBA + Nigella sativa] and [DMBA + Soybean] group]. Biochemical and histopathological analyses were done on serum and mammary glands tissue. The level of serum p53 and bcl-2 proteins was measured by ELISA and western blot techniques. The level of serum triacylglycerol [TG], cholesterol, high density lipoprotein [HDL] and low density lipoprotein [LDL] were determined spectrophotolmetrically. The protective effect of Asp, Vit.C, NS and SB was demonstrated by reducing the incidence of glandular tumors induced by DMBA from 73.3% to 50%, 43.3%, 40% and 36.6%, respectively. These protective agents, reduced also the levels of p53, bcl-2, TG and LDL, and attenuated the effect on HDL level. DMBA induced mutant p53 and bcl-2 over-expression were associated with early onset of carcinogenesis. Asp., NS, SB and Vit. C exhibited chemoprotective effect against tumor induction, through their antimutagenic effect