The Expression And Significances Of HuR And P-glycoprotein In Breast Cancer

ObjectiveTo investigate the expression profile of HuR and P-glycoprotein and their significance in breast cancer (BC) tissues.Methods1. The expression levels of HuR and P-glycoprotein were detected in a total of 82 breast cancer tissues, 20 control paracancerous normal tissues and 16 breast fibroadenoma tissues by immunohistochemistry method (S-P assay).The correlation between the expression of HuR or P-glycoprotein and the clinicalpathological parameters were analyzed.2. The association between HuR and P-glycoprotein expression and patient outcome was determined by Kaplan-Meier method and Cox proportional hazards regression model.Results1. In 82 breast cancer tissues, positive rate of cytoplasmic HuR, nuclear HuR and P-glycoprotein were 46.34% (38/82), 76.83%(63/82) and 52.44% (43/82), respectively. Compared With positive rate of cytoplasmic HuR, nuclear HuR and P-glycoprotein in paracancerous normal tissues, 5%(1/20),100.00%(2/20)and 5.00% (1/20) respectively, and the breast fibroadenoma tissues, 6.25%(1/16),100.00%(16/16)and 31.25% (5/16) respective- ely, the difference had a statistic significance (P<0.01). Both the expression of cytoplasmic HuR protein and P-glycoprotein were positively correlated with different Pathologieal types (P<0.05). In addition,the expression of cytoplasmic HuR protein was positively correlated with different ages ,and the expression of the ER/PR/C-erBb-2.tumor size. However, the expression of nuclear HuR protein was not correlated with any clinicopathological factors. The expression of the P-glycoprotein was correlated with lymph node metastasis positive.2. There was an obvious positive correlation between the expression of cytoplasmic HuR and P-glycoprotein (r=0.351, P<0.05). 3. The follow-up visit in the patients showed that five-year survival rate was greatly lower in the positive expression of the cytoplasmic HuR group than that in the negative group (P<0.05). Although the positive expression of nuclear HuR group had a lower 5 year survival rate than the negative group, there is no statistic significance. Meanwhile, the positive expression of P-glycoprotein group had a lower 5 year survival rate than the negative group obviously (P<0.05). The 5 year survival rate in the cytoplasmic HuR and P-glycoprotein double positive group was lower than the double negative group obviously. In multivariate analysis using the Cox regression model, the independent prognostic parameters for breast cancer patients included cytoplasmic HuR express (RR=2.324; 95% CI, 1.140- 4.720; P=0.025), P-glycoprotein express (RR=2.535; 95% CI 1.087-6.049; P=0.031) and lymph node metastasis (RR=2.434; 95% CI, 1.068-5.988; P=0.026), had no correlation with nuclear HuR express and other clinicopathological characteristics (P>0.05).ConclusionBoth the expression of HuR and P-glycoprotein in breast cancer tissues are closely correlated with malignant tumor progress and lymph nodes metastasis.Therefore, the expression of cytoplasmic HuR protein was positively correlated with different pathologieal types, different ages ,and the expression of the ER/PR/C-erBb-2.tumor size.The expression of HuR and P-glycoprotein are considered as poor prognosis markers of breast cancer.However,The expression of HuR in breast cancer was significantly assoeiated with axillary node positive,whieh pethaps has a close relationship with metastasis of breast cancer.It can become a target in foreeasting breast careinoma prognosis.