Research Of Shuganyishen Decoction Effect In Her2-MAPK-ER A Pathway

Breast cancer is the most common malignance in woman. The morbidity has a significantly ascending tendency, and patients in china are becoming younger. With progression of modern surgery, chemotherapy, radiotherapy, endocrine therapy, targeted therapy and biotherapy, the mobility of breast cancer has been descending. Each year, approximately50%in China,70%abroad have positive ER of their estrogen receptor. Blocking estrogen, as an endocrine therapy, is the main treating strategy. However, the resistance and relapse of cancer would cause trouble of doctors. So taking discussion and looking for methods draws a realistic significance. Results shows that ERα plays a key role in resistant chains, so does the protein kinase and its phosphorylation. Current statistics holds a view of interaction among HER2/ERα/EGFR/SRC and a view of activation in its following gene MAPK pathway. Those are the main mechanism of drug resistance. Our previous research shows that Shuganyishen Decoction with endocrine therapy can enhance the treating effect, postpone the start time of chemotherapy, alleviate side effects such as tide fever and ostalgia and prolong PFS. Outside body research shows that the decoction can inhibit proliferation and migration of MCF-7drug resistant cells. Reverse function of Shuganyishen Decoction may relate to inhibition of MAPK pathway.Objective:Research function of Shuganyishen Decoction towards HER2-MAPK-ERα pathway of tamoxifen resistant breast cancer called MCF-7, and clarify its mechanism.Method:1. Making ovariectomized female rats mode:after anesthesia, routine shaving, disinfection, making two vertical incisions beside lumbar vertebral column, separate muscle, fat, colon etc. Ligation and cut the red tiny ovaries surrounded by white fat, and suture the incisions.2. Preparing drug contained serum:after ovariectomizing, we use Shuganyishen solution (high concentration), tamoxifen solution, Shuganyishen solution (high) plus tamoxifen (equivalent effect) and physiological saline to lavage towards rats, and refine the drug contained serum.3. Using MTT to observe inhibition of serum between MCF-7WT cells and LCC9cells sorted by Shuganyishen Decoction Group, Tamoxifen Group, Combining Group and Vacant Group.4. Using Wound healing method to measure influence of serum between WT cells and LCC9cells sorted by Shuganyishen Decoction Group, Tamoxifen Group, Combining Group and Vacant Group.5. Using RT-PCR method to observe influence of serum towards mRNA expression volume derived from HER2-MAPK-ER a MAPK related genes of resistant breast cancer MCF-7LCC9cells sorted by Shuganyishen Decoction Group, Tamoxifen Group, Combining Group and Vacant Group.6. Using Western blot method to observe influence of serum towards protein expression volume derived from HER2-MAPK-ER α MAPK related genes of resistant breast cancer MCF-7LCC9cells sorted by Shuganyishen Decoction Group, Tamoxifen Group, Combining Group and Vacant Group.Results:1. Shuganyishen Decoction Group, tamoxifen group, combining group can all inhibit the proliferation of MCF-7WT cells (P<0.05), especially we find that combing group has the highest inhibition effect at48th hour (P<0.01). Shuganyishen decoction group and combing group also has the most significant inhibition effect at48th hour towards LCC9cells. Among three groups, the combing group shows the best, while tamoxifen group is not significant (P>0.05).2. Besides little inhibition towards LCC9cells in tamoxifen (P>0.05), after48hours, Shuganyishen group and combining group get some inhibition towards LCC9migration (P<0.05). Shuganyishen group, tamoxifen group and combining group can all inhibit migration of LCC9cells (P<0.05).3. RT-PCR result shows:Compared with WT cells, the mRNA expression volume of ESR1/2has descended (P<0.05), ERBB2has ascended a little (p>0.05) while that of MAPK3and MAPK14has ascended (P<0.05). After the effect of Shuganyishen group and combining group, the ESR1has risen (P<0.05), combing group has risen more sharply, but not significantly compared with the other (P>0.05). ERBB2、 MAPK3and MAPK14has fallen (P<0.05), combing group has fallen more sharply, but not significantly compared with the other (P>0.05). But MAPK9has not obvious changes p38mapk.4. Western blot result shows:Compared with WT cells, the protein expression volume of ERa has descended (P<0.05), HER-2has ascended a little(p>0.05),while that of p-p44/42mapk and p-p38mapk has ascended (P<0.05). After the effect of Shuganyishen group and combining group, the ERa has risen (P<0.05), while that of HER-2and p-p44/42mapk and p-p38mapk has descended significantly (P<0.05), p44/42mapk and p38mapk has not fallen apparently (P>0.05). Combing group has risen more sharply, but not significantly compared with the other (P>0.05). And the JNK/SAPK has not obvioue changes (P>0.05).Conclusion:1. Shuganyishen Decoction can inhibit the proliferation and migration of MCF-7WT cells and LCC9cells. Among three groups, the combining group shows the most significant inhibition effect. It suggests that Shuganyishen Decoction can enhance cytotoxic effect of tamoxifen and delay or reverse the tamoxifen resistance.2. Shuganyishen Decoction can enhance the expression of ERa and decline the expression HER-2and p44/42mapk and p38mapk of tamoxifen resistant breast cancer MCF-7LCC9cells, however, the impact for the JNK/SAPK is not very significant. Shuganyishen Decoction can inhibit the expression of ERK1/2MAPK、P38MAPK pathway, In this way, the cells of breast cancer MCF-7LCC9can improve the expression of ER alpha and decline the expression of HER-2,which plays a imptartant role in the reversal of drug resistance.