)pyrene in Human Breast Cancer MCF-7 Cells a Benzo( A New Functional Role for P-Glycoprotein: Efflux Pump for
نویسندگان
چکیده
We propose that the cellular burden of certain carcinogens may be mitigated by P-glycoprotein (P-gp), the putative drug effiux pump. In a series of multidrug resistant human breast cancer MCF-7 cells with increasing P-gp expression we examined this hypothesis using benzo(a)pyrene, a widely distributed environmental and dietary carcinogen. We found that multidrug resistant cells were cross-resistant to benzo(a)pyrene and the rates of efflux for benzo(a)pyrene were higher in multidrug resistant cells than in wild type cells. Evidence supporting the involvement of P-gp included the inhibition of azidopine binding to P-gp bel,zo(a)pyrene and the inhibition of benzo(a)pyrene efflux by Adriamycin and verapamil. Our findings suggest that P-gp may play a role in the cellular defense to carcinogens. The expression of P-gp and the modulation of its function may affect the susceptibility of normal tissues to transformation by carcinogens.
منابع مشابه
A new functional role for P-glycoprotein: efflux pump for benzo(alpha)pyrene in human breast cancer MCF-7 cells.
We propose that the cellular burden of certain carcinogens may be mitigated by P-glycoprotein (P-gp), the putative drug efflux pump. In a series of multidrug resistant human breast cancer MCF-7 cells with increasing P-gp expression we examined this hypothesis using benzo(alpha)pyrene, a widely distributed environmental and dietary carcinogen. We found that multidrug resistant cells were cross-r...
متن کاملA New Functional Role for P-Glycoprotein: Effiux Pump for Benzo(a)pyrene in Human Breast Cancer MCF-7 Cells
We propose that the cellular burden of certain carcinogens may be mitigated by P-glycoprotein (P-gp), the putative drug effiux pump. In a series of multidrug resistant human breast cancer MCF-7 cells with increasing P-gp expression we examined this hypothesis using benzo(a)pyrene, a widely distributed environmental and dietary carcinogen. We found that multidrug resistant cells were cross-resis...
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We used a series of P-glycoprotein (P-gp) expressing multidrug-resistant (MDR) cells, developed from human breast cancer MCF-7 cells by exposure to Adriamycin, to investigate the effects of flavonoids on P-gp-mediated efflux mechanisms for chemical carcinogens. We previously showed that MDR cells derived from exposure to Adriamycin are cross-resistant to a chemical carcinogen, benzo(a)pyrene, d...
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