Expression And Significance Of Estrogen Receptor β In Breast Cancer And Adjacent Tissue

Background: Breast cancer is one of the most common female malignant tumors. Estrogen plays an important role in the generation and development of the cancer . After ER P was found in the cancer tissue , it is necessary to make further studies of the molecular basement and mechanism and the clinical significance Objectives: To study the expression and significance of ERP in breast cancer tissue , and to find the correlation between breast cancer generation and the expression of ER P . Methods: 97 cases of operable primary breast cancer were collected. Retrospective cohort study and case-control study were mainly used. ERa , ER3 and PR were detected by S-P immunohistochemical technique. The data was analysed combining with biochemical ER , PR, clinicopathological characters , prognosis and the effect of endocrine therapy using chi-square test , Kaplan-Meier method , Log-rank test , Cox regression. Results: (1) ERa , ER$ and PR are all nuclear receptors. (2)The ER ?positive rates in adjacent cancer and cancer tissues are 91.8%(56/61) and 62.9%(61/97) respectively. The difference is significant (P<0.001). There is cause-effect relation between the decrease of ER?expression and breast cancer generation. (3)There is no correlation between the expression of ER ?and that of ERa (P>0.05). The ERP positive rate is 83.33% (10/12) in the breast cancer tissues in which ER a , biochemicalER , PR , immunohistochemical PR are all negative. (4)The expression of ER?is inversely correlated with histological grade (P<0.001) and involved axillary lymph node number(P<0. 01) . There is no difference in other clinicopathological characters groups (P>0.05). ER ?is not correlated with these clinicopathological characters. (5) The expression of ER a is inversely correlated with the tumor size (P=0.011) and histological grade (P<0.01). The expression of PR is not correlated with clinicopathological characters . (6) In univariant analysis 3-year and 5-year overall survival rates, disease free survival rates and non-far metastatic rates in ER?positive group are all higher than those in ER ?negative group (P<0.01) . In multiple variants analysis, ER P , involved axillary lymph node number, menstrual state and ER a are the independent factors which might affect overall survival rates, disease free survival rates and non-far metastatic rates(P<0.05 or 0.01).(7)In ER 0 positive patients 3-year and 5-year overall survival rates, disease free survival rates and non-far metastatic rates in endocrine therapy group are higher than those in control group(P<0.05 or 0.01),but not in ER?negative patients (P>0.05). Conclusions: (1) ERa , ER0 and PR are all nuclear receptors. (2) ER 3 widely expresses in adjuvant breast cancer tissues and also expresses in the cancer tissues. The expression in adjuvant breast cancer tissues islower than that in the cancer tissues. There is cause-effect relation between the decrease of ER13 expression and breast cancer generation. (3) In breast cancer tissues the expression of ER 13 is inversely correlated with histological grade and involved axillary lymph node number. The expression of ERa is inversely correlated with the tumor size and histological grade. The expression of PR is not correlated with c linicopathological characters. (4) In breast cancer tissues there is no correlation between the expression of ER 13 and that of ER a . The detection of ER 13 can not be taken place by the combined detections of ER , PR and ERa . (5) ER i3 is of value to asses the prognosis. It is an independent factor. (6) ER {3 is also of value to assess the effect of endocrine therapy. It will make effect on the ER3 positive breast cancer.