Expression Of Podocalyxin In Breast Cancer Tissues

Objective:To discuss podocalyxin expression difference between in ductal carcinoma in situ(DCIS)and in invasive ductal carcinoma(IDC),and to observe the expression of podocalyxin in low/middle grade DCIS and high grade DCIS.The expression of podocalyxin in IDC was compared with the prognosis and clinicopathological parameterst,such as patient's age,tumor size,tumor grade,p TNM stage,lymph nodes metastasis and family history.To discuss their role in tumour progression and their relationships with pathology features and prognosis of breast cancer.Methods :Immunohistochemical SP method was used to checked the expression of podocalyxin of DCIS(33 specimens of low/intermediate grade DCIS and 29 specimens of high grade DCIS)and 129 specimens was of IDC,who were treated at our institution between January 2004 and December 2006.We used Western Blot to check the expression of podocalyxin in normal breast tissues,DCIS tissues and IDC tissues.Data were analyzed by SPSS19.0 statistical software.The comparison of qualitative data was performed by ?2 test.Kaplan-Meier survival curve was used for single factor survival analysis.Cox multivariate analysis model was used for multivariate analysis.Statistical results with P<0.05 for the difference was statistically significant.Results:1.Among the 62 DCIS specimens,the expression of podocalyxin were 35.48%(22/62),40 specimens(64.52%)were negative.In 33 specimens of low/middle grade DCIS,8 specimens(24.24%,8/33)showed podocalyxin positive.In 29 specimens of high grade DCIS,14 spesimens(48.28%,14/29)were expressed podocalyxin.It was preferentially expressed in high-grade DCIS,compared with low/intermediate-grade DCIS(P<0.05).2.The expression of podocalyxin in IDC was as follows:67 specimens(51.94%,67/129)showed positive expression and 62 specimens(48.06%)were negative.3.The expression of podocalyxin in IDC was higher than in DCIS,the difference was statistically significant((P<0.05).4.It was preferentially expressed in high-grade DCIS,compared with low/intermediate-grade DCIS(65.22% vs.44.57%,P=0.024).Podocalyxin expression in IDC associated with tumor grade,p TNM stage and lymph node metastasis in IDC(P<0.05).5.Kaplan-Meier univariate analysis revealed podocalyxin positive expression and other factors had significance for disease free survival.Cox model analysis revealed podocalyxin positive expression and lymph nodes metastasis were dangerous independent prognosis factors for IDC.6.The result of Western Blot showed the expression of podocalyxin was significantly higher in IDC and DCIS than normal breast tissues.Between the low/middle grade DCIS tissues and high grade DCIS,the expression of podocalyxin showed no significant differences.Conclusion:Podocalyxin expressionis significantly higher in IDC than that in DCIS.Podocalyxin could be an important index for the development and invasive of breast cancer.In IDC patients,podocalyxin positive expression is closely associated with poor prognosis.