Correlation Between COX-2, Smac Expression And HER2 Status In Breast Invasive Ductal Carcinoma And Its Significance

Objectives: To investigate the relationship between COX-2,Smac expression and HER2 status in breast invasive ductal carcinoma,and to explore its relationship with clinicopathological features.In order to provide a new target for prognosis of breast cancer.Methods:1.The subject investigaated63 case of surgical treatment which were diagnosed as breast infiltrating ductal carcinoma were collected and prescreened from the CANGZHOU People’s Hospital during July 2016 to July 2017.Select 34 case of normal breast tissues by the same method as control.Select 63 cases of patients,who had no received chemotherapy,radiotherapy,endocrine therapy and molecular targeted therapy,with no previous history of cancer patients.Tumor tissue samples were taken within 30 min of in vitro,divided into two parts.One part was fixed in 10% neutral formalin solution,paraffin embedded for testing,and the other part was stored in-80 °C refrigerator for extracting RNA.2.Real-time fluorescence quantitative polynucleotide chain reaction(RT-qPCR)was used to detect the relative genes expression of COX-2 and Smac in 63 IDC patients and 34 normal breast tissues.2.Immunohistochemistry(IHC)was used to detect the protein expression of COX-2 and Smac in 63 patients with IDC and 34 normal breast tissues.4.Immunohistochemistry(IHC)was used to detect the expression of HER2 in 63 patients with IDC.For cases with immunohistochemical results of 2+,FISH was performed to verify the amplification status of HER2.Result:1.The expression of COX-2 in IDC and its relationship with clinicopathological featuresRT-qPCR results showed that the relative expression of COX-2 gene in IDC tissues(0.10±0.04)was significantly higher than that in normal breast tissues(0.006±0.004)(P<0.05).The results of IHC assay showed that the positive rate of COX-2 protein in 63 IDC tissues was 50.79%(32/63),and the positive rate in 34 normal breast tissues was 11.76%(4/34).The positive rate of COX-2 protein in IDC tissues was significantly higher than that in the normal breast tissues,and the difference was statistically significant(P<0.05).Combined with the clinician pathological features analysis,COX-2 expression was associated with IDC lymph node metastasis and histological grade(P < 0.05);but was irrelevant with age,tumor size,vascular tumor thrombus,nerve invasion,ER,PR expression(P>0.05).2.Smac expression in IDC and its relationship with clinicopathological featuresRT-qPCR results showed that the relative expression of Smac gene in IDC tissues(0.12±0.06)was significantly lower than that in normal breast tissues(0.17±0.09)(P<0.05).The results of IHC assay showed that the positive rate of Smac protein in 57 IDC tissues was 57.14%(36/63),and the positive rate in 34 normal breast tissues was 76.47%(26/34).Smac protein was expressed in IDC tissues.The difference was statistically significant(P<0.05).Combined with clinical patient characteristics analysis,Smac expression was irrelevant with age,tumor size,lymph node metastasis,histological grade,vascular tumor thrombus,nerve invasion,ER,PR expression(P>0.05).3.Relationship between HER2 status and clinicopathological features in IDC tissuesThe expression of HER2 protein in 63 cases of breast IDC was detected by IHC method.The results of interpretation of 0 were 28.57%(18/63),1+ accounted for 19.05%(12/63),and 2+ accounted for 20.63%(13/63),3+ accounted for 31.75%(20/63).0~1+ was directly judged as HER2 negative;3+ was directly judged as HER2 positive;13 cases of IDC tissues of 2+ were further tested by FISH to determine the amplification status of HER2 gene.FISH results showed that 1 of 13 cases of IHC2+ had HER2 amplification.It was finally determined that there were a total of 21 IDC tissues with HER2 amplification.The positive rate of HER2 in 63 cases of IDC was 33.33%(21/63).The consistency of IHC and FISH was consistent by Kappa test consistency analysis(Kappa=0.964,P<0.05).Combined with the clinicopathological features of patients,HER2 status was associated with lymph node metastasis,histological grade,and vascular tumor thrombus(P<0.05),but was irrelevant with age,tumor size,nerve invasion,ER,PR expression,(P>0.05).4.Relationship between COX-2,Smac expression and HER2 status in IDC tissuesThe results of IHC and FISH showed that the expression of COX-2 protein in IDC tissues was significantly correlated with HER2 positive status(P<0.05).There was no correlation in the expression of Smac protein and HER2 status,COX-2 protein expression and Smac protein in IDC(P>0.05).Conclusion:1.The expression of COX-2 in breast invasive ductal carcinoma is significantly higher than that in normal breast tissue.It is associated with lymph node metastasis and histological grade.2.The expression of Smac in breast invasive ductal carcinoma was significantly lower than that in normal breast tissue.3.HER2 status in breast invasive ductal carcinoma was well consistent with FISH results.4.Combined detection of COX-2,Smac,and HER2 status in breast cancer tissues is expected to be an important indicator for predicting breast cancer prognosis.