The Study On The Effects Of Using Different Doses Of Genistein During Pregnancy On Vascular Endothelial Growth Factor Expression In The Offsprings Of Mice Mammary Tumors

Objective This experiment study the effects on the mammary tumors of Erb-2 transgenic mice exposed to genistein during pregnancy by using different doses of genistein, aimed at understanding chemoprevention role of the phytoestrogen genistein in breast cancer and discuss the effects on breast cancer for future generations because pregnant women eat different doses of genistein, as well as its role in the molecular biology mechanisms.Methods the differences in the tumor latency and breast cancer tumor rate between female offsprings of mice of the different doses groups including high-dose15mg/(kg·d),middle-dose 5.0 mg/(kg·d),low-dose 1.0 mg/(kg·d)of genistein by subcutaneous injection from day 13 to day 19 of gestation and control group were analyzed by statistical methods, the expression of VEGF and breast cancer organization microvessel density in the offsprings of mice. mammary tumors paraffin section were detected by immunohistochemistry staining SP method.Results there was a significant difference in breast cancer tumor latency and breast cancer tumor rate between the high-dose group and middle-dose group,low-dose group,control group(P<0.05).46.7±4.8 weeks of breast cancer tumor latency in the high-dose group extended by about 9 weeks,9.6 weeks,10.5 weeks, compared with 38.1±4.4 weeks of breast cancer tumor latency in the middle-dose group,37.2±4.7 weeks of breast cancer tumor latency in the low-dose group,36.3±4.7 weeks of breast cancer tumor latency in the control group . 30% of breast cancer tumor rate in the high-dose group reduced by 30%,33%,43%, compared with 60% of breast cancer tumor rate in the middle-dose group,63% of breast cancer tumor rate in the low-dose group,73%of breast cancer tumor rate in the control group; however no significant difference among the middle dose group, the low-dose group and control group(P >0.05). 33.4%of the positive expression of VEGF levels in the high-dose group declined by 38.9%,39.3%,40%,compared with 72.3% of the positive expression of VEGF levels in the middle-dose group,72.7%of the positive expression of VEGF levels in the low-dose group,73.4%of the positive expression of VEGF levels in the control group; 10.26±1.77 of breast cancer organization microvessel density in the high-dose group declined by about 6.87,6.9,7.17 , compared with 16.85±2.05 of breast cancer organization microvessel density in the middle-dose group,17.16±2.00 of breast cancer organization microvessel density in the low-dose group,17.39±1.81 of breast cancer organization microvessel density in the control group; however no significant difference among the middle dose group, the low-dose group and control group(P >0.05).Conclusions Using high doses of genistein during pregnancy can make the extension of mean breast cancer tumor latency, the decline of breast cancer tumor rate, the decline of VEGF positive expression levels and the decline of breast cancer organization microvessel density of female mice offsprings . This experiment study illustrates the pregnant women eat foods rich in genistein, such as soybeans and soy products may prevent the occurrence of breast cancer for future generations,but it requires a large number of clinical trials to further study.