Expression And Clinical Significance Of MUC1 And WWP1 In Breast Cancer

Background:Breast cancer is one of the malignant tumors that endangers women’s health,and its incidence is increasing year by year.The classical subtypes of breast cancer play a key role in the treatment and prognosis of breast cancer.We tried to find some new tumor markers to provide new clues for the diagnosis and treatment of breast cancer.Mucin 1(MUC1)is abnormally overexpressed in 70%of solid tumors,especially in more than 90%of breast cancer,which is closely related to tumor malignancy and poor prognosis.So,inhibiting the function by degrading overexpressed MUC1 protein is expected to provide a new strategy for the treatment of tumors.There was a negative correlation between MUC1 and an E3 ubiquitin ligase-WWP1 in normal tissues and various tumor tissues.We recently find that WWP1 can degrade MUC1 protein depend on its ubiquitin ligase activity,however,the expression of WWP1 and MUC1 in breast cancer and their correlation between classical subtypes of breast cancer,as well as its effect on the survival of breast cancer patients have not been reported.Objective:To verify the correlation between WWP1 and MUC1 protein expression in breast cancer,analyze the correlation between the expression of WWP1 and MUC1 and classical subtypes of breast cancer,and then verify the effect of its expression on the prognosis of breast cancer.Methods:A total of 108 paraffin-embedded pathological sections of human breast cancer patients who underwent breast cancer surgery from October 2010 to May 2015 from the Xiangya Hospital of Central South University to analyze the expression and correlation of WWP1 and MUC1 protein by immunohistochemistry(IHC),and the survival analysis of breast cancer patients.Results:(1)In 108 breast cancer samples,there was a reverse correlation between the expression levels of WWP1 and MUC1(r=-0.514,p<0.01),furthermore,out of 37 specimens that had both high expression of WWP1 and MUC1,29 of them(82.4%)displayed different distribution of WWP1 and MUC1 in tumor cells.(2)The expression of WWP1 and MUC1 in breast cancer was not related to subtypes(p>0.05),but the expression of four groups(high WWP1+high MUC1,low WWP1+high MUC1,high WWP1+low MUC1 and low WWP1+low MUC1)was different in different breast cancer subtypes(p<0.001).(3)The survival curve of the high WWP1+low MUC1 group had no difference between other three groups(p>0.05).Conclusion:There was a negative correlation between the expression of WWP1 and MUC1 in breast cancer;its correlation varied according to the subtypes of breast cancer;and the correlation between WWP1 and MCU1 expression in breast cancer tissues were not related to prognosis;the negative regulatory effect of WWP1 on MUC1 may provide new ideas for the treatment of MUC1-positive breast cancer.