The Application Of Detection For Circulating Her-2 MRNA In Diagnosis Of Breast Cancer

Objective:The significance of this study is to investigate the expression of circulating Her-2 mRNA in patients with breast cancer by RT-PCR, evaluate the values in early diagnosis of breast cancer and provide effective reference to the development of new method in oncodiagnosis.Methods:30 cases of serum of healthy persons with different sex and ages were selected as normal conctrol group. Breast cancer group was composed of 60 cases of serum of patients with breast cancer, confirmed by the pathology or the cytology diagnosis.30 cases of serum of patients with diabetes, hypertension, pneumonia or other innocuousness disease were selected as nontumors group. Circulating RNA were extracted from serums and the expression of circulating Her-2 mRNA were detected by RT-PCR.60 cases of breast cancer without radiotherapy and chemotherapy were investigated. All samples were examined by immunohistochemistry method for HER-2 expression.Results:Circulating Her-2 mRNA was not detected by RT-PCR in healthy groups and nontumorous groups, but detected in breast cancer groups. The positive rate was 45.0%(27/60),24 cases were infiltrating duct carcinoma(one case was stage 1,15 cases were stageⅡand 8 cases were stageⅢ),3 cases were medullary carcinoma(2 cases were stageⅠ,1 case was stageⅡ). No statistical significance was found in the correlation of HER-2 mRNA with the age of patients,the size of tumour and TNM staging (P>0.05).HER-2 mRNA is significantly related to the metastasis of axillary lymph nodes (P<0.05). The positive rate was 52.63% in positive axillary lymph nodes breast cancer, significantly higher than that in negtive axillary lymph nodes breast cancer (31.82%). Her-2 was expressed in the cell membrane and positive rate was 48.3%(29/60). It was not detected in normal breast tissue.26 cases were infiltrating duct carcinoma(2 cases were stage I,15 cases were stageⅡand 9 cases were stageⅢ),3 cases were medullary carcinoma(2 cases were stageⅠ,1 case was stageⅡ). No statistical significance was found in the correlation of HER-2 mRNA with the age of patients,the size of tumour and TNM staging (P>0.05).HER-2 mRNA is significantly related to the metastasis of axillary lymph nodes (P<0.05). The positive rate was 57.89% in positive axillary lymph nodes breast cancer, significantly higher than that in negtive axillary lymph nodes breast cancer (31.82%).Conclusion:This study shows the expression of cirulating Her-2 mRNA was significantly enhanced in patients with breast cancer. This result is in concordance with the result of the expression of Her-2 in the breast cancer tissues by immunohistostaining method. The expression of Her-2 mRNA is closely related to the metastasis of breast cancer, but not related to the patients'age and the size of tumor. It signifies that tumor cells have higher invasive ability and poor prognosis. The determination of circulating Her-2 mRNA may provide novel and noninvasive marker in early diagnosis and prognosis of breast cancer.