The expression of multi-drug resistance gene in breast cancer stem cells and its significance
LI Zhi,LIU Chun-ping,HE Yan-li,ZHANG Jing-hui,HUANG Tao (Department of Breast and Thyroid Surgery, Union Hospital,Huazhong University of Science and Technology,Wuhan 430022,China)
Objective:To detect the expression of multi-drug resistance genes MDR 1 and BCRP in breast cancer stem cells and differentiated cells as well as discuss their clinical significance. Methods:The breast cancer stem cells were separated from human primary breast cancer tissue and MCF-7 cells by flow cytometry-based selection on freshly isolated cells. The expressions of MDR 1 and BCRP in different subsets of cells was measured by real-time PCR. Results:Compared with breast cancer differentiated cells, the expressions of MDR 1 and BCRP in breast cancer stem cells were significantly higher (P0.01), and the proportion of stem cells markedly increased after chemotherapy (P0.01). Conclusion:Compared with breast cancer differentiated cells, breast cancer stem cells have stronger drug-resistance against chemotherapy via over-expression of multidrug resistance genes, which is one of the key factors for failure of chemotherapy and recurrence of breast cancer.