CHEMOPREVENTION OF DMBA-INDUCED MAMMARY-GLAND CARCINOGENESIS PREVENTIVE EFFECTS OF FREE OXYGEN RADICAL SCAVENGERS

This study was carried out to determine the effects of Mangan-Desferri oxamine (Mn-DFX) and Verapamil (VRP) in 7,12-dimethyl-benz-[a]anthrace ne (DMBA) induced mammary carcinoma. 70 Spraque Dawley rats were divid ed into four groups; as DMBA alone, DMBA + Mn-DFX, DMBA + VRP, and con trol. Incidence, multiplicity, and size of tumors were evaluated in ad dition to analyses of DNA ploidy status and proliferation index by flo w cytometric technique. The results revealed that Mn-DFX and VRP cause d significant decreases in tumor incidence (p < 0.02 and p < 0.05), mu ltiplicity (p < 0.02 and p < 0.05), size (p < 0.05 and p < 0.02), and proliferation index (p < 0.05 and p < 0.02) without any toxic effect. The appearance of first tumors in Mn-DFX and VRP groups was also later than in the DMBA alone group (10th and 11th week versus 6th week). In conclusion, Mn-DFX and VRP have offered prevention in experimental ma mmary carcinogenesis. These agents caused slower tumor growth, though they could not achieve a complete prevention.