Correlation Between Expression Of SBEM With Prognosis And Epithelial Mesenchymal Transformation In Triple-Negative Breast Cancer

Background&Obiective: Breast cancer is one of the most common malignant tumors in women, and the metastasis is the major cause of death in breast cancer. The triple-negative breast cancer(TNBC) is a kind of invasive breast cancer and prognosis is poor, the recurrence and metastasis risk is higher. Small breast epithelial mucin(SBEM) as specific markers of breast cancer, and closely related to breast cancer micrometastases. Epithelial to mesenchymal transition(EMT) play an important role in tumor dissemination and spread, whether in primary tumors or secondary tumors. The study of SBEM in EMT is rarely report in breast cancer. In the present study, explore expression level of SBEM and prognosis, discuss its correlation with EMT in the triple-negative breast cancer. Methods: Collecting specimens of 141 cases of breast cancer, including 98 cases of TNBC,43 cases of non TNBC, 32 patients of breast cancer adjacent tissues and 20 patients of normal breast tissue with patient’s clinical data. Iimmunohistochemical for SBEM 、 E-cadherin 、 Vimentin was performed in triple-negative breast cancer. The relationship between SBEM and clinical pathological factors, lymph node metastasis, prognosis in the triple-negative breast cancer is analyzed. Additionally, the relationship between SBEM and E-cadherin、Vimentin in patients is analyzed. Results: 1.SBEM is mainly expressed in the membrane of tumor cells and the positive rate is 47.5%(67/141). The positive rate is 54.1%(53/98)of TNBC is much higher than that of in non TNBC(34.9%)(P = 0.036).The positive rate is 18.8%(6/32) in adjacent tissues of breast cancer and 0%(0/20)of normal breast tissue. There is significant difference both of them compared with the TNBC in the rate(P=0.000);2.The expression of SBEM is positively correlated with pathologic stage, lymph node metastasis and Ki67.There is no correlation between SBEM and age, menstrual status, tumor size, pathologic type, histological grade or P53;3. E-cadherin is mainly expressed in the membrane of tumor cells. The expression of SBEM negatively correlated with E-cadherin(r=-0.713,P=0.000)and positively correlated with Vimentin which is expressed in the plasma of tumor cells(r=0.733,P=0.000);4. The expression of Vimentin in the lymph node-positive group is higher than that in lymph node-negative group(Z=-3.079,P=0.002). The expression of E-cadherin in the lymph node-positive group is lower than that in lymph node-negative group(Z=-2.703,P=0.007). Expression of SBEM had significantly consistent with expression of E-cadherin and Vimentin(Kappa>0.7,P<0.05);5. Univariate Kaplan-Meier analysis reveal that whether lymph node-positive group or lymph node-negative group, there is negative correlation between overexpression of SBEM and survival(P < 0.05); 6.Cox-regressiong analysis indicate that the overexpression of SBEM and lymph node metastasis are an independent prognostic factor for TNBC(P<0.05).Conclusion: SBEM probably promotes invasion and metastasis through EMT in TNBC.Moreover, overexpression of SBEM is correlated with poor prognosis, and can as an independent prognostic factor for TNBC.