Expression And Clinical Significance Of Multidrug Resistance Gene MDR1 And P-gp, C-erbB-2 Protein In Breast Cancer

Objective To detect the expression of multidrug resistance gene 1(MDR1) and P-gp, C-erbB-2 protein in breast cancer and study the relationship with clinicopathology parameters and also the correlation between MDR1/P-gp and C-erbB-2.Method Expression of MDR1 gene was measured with the fluorogenic quantitative RT-PCR method in 49 cases of breast cancer and 16 cases of control group (including 8 cases of benign breast lesions and 8 cases adjacent breast tissues). In addition, immanohistochemical analyses was used to detect the expression of P-gp and C-erbB-2 protein in above mentioned tissues.Result The amplification rate of a MDR1 gene in breast cancer group was 5 1.02%(25/49), which was not found in control group. The expression of P-gp protein in normal controls was megative except one case of mastopathy was positive. The positive rate of P-gp protein in breast cancer group was 42.86%(21/49), and the expression of P-gp was independent of age, tumor size, lymphnode involvement , clinical stage, estrogen receptor, progesterone receptor status and menopause status . The amplification of MDR1 gene was higher than the expression of P-gp protein ,there was close correlation between them but not complete correspondence . No positive case was found in detecting the overexpression of C-erbB-2 in control group, nevertheless, the positive rate in breast cancer group was 61.22%(30/49), The overexpression of C-erbB-2 was closely correlated with the lymphnode involvement while inverselycorrelated with ER, PR status.There was no correlation between the overexpression of C-erbB-2 protein and age^ tumor size^ clinical stage and menopause status. The expression of MDRl/P-gp was also correlated with the overexpression of C-erbB-2.Conclusion Multidrug resistance gene l(MDRl)and protooncogene C-erbB-2 was correlated with the multidrug resistance in breast cancer, to detect the expression of the two genes may be helpful in choosing the treatment of breast cancer with chemotherapy endocrine therapy and gene therapy.