Expressions of MDR1,BCRP and LRP genes in breast cancer tissues and their significance

Objective To investigate the expressions of multidrug resistance gene(MDR1),breast cancer resistance protein(BCRP) and lung resistance protein(LRP) mRNA in breast cancer and their correlation,and to analyze their relationship with clinical and pathological features of breast cancer.Methods We adopted RT-PCR method to detect the expression levels of MDR1,BCRP and LRPmRNA in 42 cases of breast cancer tissues,42 cases of adjacent tissues and 30 cases of benign breast lesions,who came to the Affiliated Hospital of Ningxia Medical University for resection between January and December 2007.Results The positive expression rate of MDR1 mRNA,BCRP mRNA and LRPmRNA was 40.47%,38.09% and 61.90% in patients with breast cancer.It differed significantly from that in the adjacent tissues and benign breast lesions(P0.05).The expression of MDR1 mRNA had a completely positive correlation with menopausal status and axillary lymph node status in breast cancer patients(r=0.398,P0.01).The expression of BCRP mRNA had a positive correlation with axillary lymph node status(r=0.355,P0.05).The expression of LRP mRNA had no correlation with menopausal status,age,axillary lymph node status or tumor size(P0.05).The expressions of MDR1 mRNA and BCRP mRNA were positively related(r=0.652,P0.01),and LRP mRNA expression was not related to the expression of MDR1 mRNA(r=0.147,P0.05) or BCRP mRNA(r=0.111,P0.05).The co-expression rate of two resistance genes was 47.61% while that of two or three types of resistance genes was 61.89%.Conclusion Multidrug resistance gene(MDR1),breast cancer resistance protein(BCRP) and lung resistance protein(LRP) mRNA are co-expressed in breast cancer;single gene and multiple genes are synergetic and the co-expression of multiple genes is more important.Detecting the expression of MDR1 and BCRP genes can help determine the prognosis of breast cancer in clinic.