The Establishment of P-gp Expression on Cell Line and its Biological Characteristics

Objective 　To establish a cell line expressing P-glycoprotein ( P-gp) stably by gene transduction and drug inducement, to screen drugs used to specifically reverse P-gp. Methods 　P-gp DNA of tumor cells in mice that was obtained by RT-PCR was transfered into colibacillus, constructed plasmids DNA and transduced it into ret roviral vector, then to t ransfect B-MD-C1 cell. Northern blot analysis was used to investigate P-gp mRNA and flow cytometry was performed to assess the expression of P-gp. Proliferation assay was measured by MTT method. The biological characteristics of P-gp positive cell line were evaluated by drug accumulation assays and drug efflux assays. Results 　B-MD-C1 (ADR + / + ) cell expressing P-gp stably was established. Significant overexpression of P-gp on B-MD-C1 (ADR + / + ) cell was induced by Adriamycin, the cell survior of B-MD-C1 (ADR + / + ) was 80 % when the concentration of Adriamycin was 12 000ng/ mL, while the cells of B-MD-C1 (wt) were all died when the concent ration of Adriamycin was 1 000ng/ mL. The accumulation of MD-123 in B-MD-C1 (ADR + / + ) was lower than in B-MD-C1 (wt), the efflux of MD-123 in B-MD-C1 (ADR + / + ) was higher. But the accumulation of MD-123 was significantly increased and the cells efflux was vanished in B-MD-C1 (ADR + / + ) with Verapami. Conclusion 　B-MD-C1 (ADR + / + ) is multidrug resistant, Verapami can reverse its resistance of P-gp. B-MD-C1 (ADR + / + ) cell line can be used to screen drugs, those having the same character with Verapami may specifically reverse P-gp resistance.