The Significance of CXCR4 Expression for the Prediction of Lymph Node Metastasis in Breast Cancer Patients

OBJECTIVE The chemokine receptor(CXCR4)CXC chemokine receptor 4)plays an important role in cancer metastasis.We therefore studied differential expression of the CXCR4,as well as that of the biomarker HER2,so as to evaluate whether these biomarkers can be used to predict axillary lymph node metastasis in breast cancer patients. METHODS Immunohistochemistry was used to evaluate the CXCR4 and HER2 expressions and to examine the paraffin sections of the breast cancers at various stages.Positive lymph node expression was found in 80 of the cases,and in 7 there was negative expression. RESULTS Compared to the cases with negative lymph nodes, there was a high expression of CXCR4(26.3% vs.14.3%,P=0.013), and an over-expression of HER2(28.8% vs.14.3%,P=0.011). Moreover,there was a direct correlation between the CXCR4 and HER2 expressions and the tumor staging(P=0.000)and lymph node metastasis(P=0.032).When the two biomarkers,i.e.CXCR4 and HER2,were concurrently labeled,a high expression of one of the biomarkers could be seen in the cases with positive lymph nodes(51.3% vs.28.6%,P<0.003). CONCLUSION The chemokine receptor,CXCR4,is a new-type biomarker in predicting axillary lymph-node metastasis in breast cancers.Compared with the other markers,such as HER2 etc., assessment of CXCR4 can improve the prediction of the presence and extent of lymph node involvement.