Figure 2. Expression of P-glycoprotein (P-gp) in MCF-7 and MCF-7R cells. (A) The mRNA levels of multi-drug resistance (MDR1) gene in MCF-7 and MCF-7R cells by qRT-PCR. (B) The protein expression of P-gp in MCF-7 and MCF-7R cells using western blotting. (C) The expression of P-gp in MCF-7 and MCF-7R cells by cell immunofluorescence.