The Effect Of Soybean Isoflavone On The Expression Of MMP-2and TIMP-2in Mmtv-erbB-2Transgenic Mice’s Breast Tumor

Objiective： This experiment using the MMTV-erbB-2transgenic mice,discusses the influence of the soybean isoflavone (GST) with different processingstage to the occurrence and development of MMTV-erbB-2transgenic mice ’s breasttumor.Methods：120female MMTV-erbB-2transgenic mice were selected anddivided into four group, Bean feed intervention group: treated the mice with bean feedcontain soybean isoflavones since four weeks after born; GST slow-releasemicrospheres intervention group: subcutaneous injection GST/PLGA slow-releasemicrospheres (1time/month) since four weeks after born; Ordinary feed interventiongroup: treated the mice with ordinary feed contains no soybean isoflavones since fourweeks after born; Empty microspheres intervention group: subcutaneous injectionPLGA empty microspheres (1time/month) since four weeks after born. Observed thegrowth and the development of the mice, recorded the mice’s weight changes,observed the incidence of breast cancer of the mice, the tumor latent period, record thelocation and the growth situation of the tumor, made HE staining to observe thepathological type, using the immunohistochemistry staining to detected the MMP-2and TIMP-2’s expression in both normal breast tissue and breast tumor tissue of eachgroup,and analyzed their relationship.Results：The study found that the growth and the weight changes of the micehad no significant difference (P>0.05). The incidence of breast tumor in bean feedintervention group, GST slow-release microspheres intervention group, common feedintervention group and empty microspheres intervention group were13.3%，36.7%，70%和66.7%. The incidence of breast tumor in bean feed intervention group weresignificantly reduced compared with the controlled feed intervention group, thedifference had statistically significant (P <0.05). The incidence of breast tumor in GST microspheres intervention group were significantly reduced compared withempty microspheres intervention group，the difference had statistically significant (P<0.05). The incidence of breast tumor in the bean feed intervention group was lowerthan GST microspheres intervention group, the difference had statistically significant(P <0.05). The incidence of breast tumor of the bean feed intervention groupcompared with the empty microspheres intervention group, the difference had nostatistically significant (P﹥0.05). Most of the tumors located on the second and thethird mammary gland, the maximum average diameter of the tumor in each groupscompared to each other had no statistically significant difference (P>0.05). All thebreast tumor tissues were determined to be breast cancer organizations by H E staining.The MMP-2and TIMP-2’s expression in breast tumor tissues were both higher than innormal breast tissues, the difference was statistically significant (P <0.05),the MMP-2and TIMP-2’s expression in breast tumor tissues had a negative correlation, and theirexpressions in normal breast tissue were unrelated. The positive rate of MMP-2inbean feed intervention group, GST slow-release microspheres intervention group,common feed intervention group and empty microspheres intervention group’s breasttumor tissue were75%,83.3%,71.4%和73.9%, the difference compared with eachother had no statistically significant (P=0.888). The positive rate of TIMP-2in beansfeed intervention group, GST slow-release microspheres intervention group, commonfeed intervention group and empty microspheres intervention group’s breast tumortissue were25%，33.3%，39.2%和43.5%, the difference compared with each otherhad no statistically significant (P=0.876).Conclusion：1. Soybean isoflavone can restrain the breast tumor on MMTV-erbB-2transgenic mice.2. Soybean isoflavone’s inhibition effect on the breast tumor decreased with theprocessing level’s rise.3. Soybean isoflavone intervention is irrelevant to the metastasis and prognosisof breast tumor...