Figure 5.
Effect of rociletinib on the expression of ABCG2 in MDR cells. (A) The protein level of ABCG2 on MDR cells after 0, 0.25, 0.5 and 1 μmol/L rociletinib stimulation for 48 h were measured by Western blot analysis. (B) The level of mRNA was measured by PCR (GAPDH as loading control), real time-PCR was further applied to confirm the unaltered mRNA levels in MDR cells. Rociletinib did not alter the mRNA and protein levels in MDR cells in concentration dependent manner. (C) The cell surface expression of ABCG2 was measured by flow cytometry before and after rociletinib stimulation on MDR cells and their parental cells. (D) The internalization of ABCG2 on MDR cells was measured by immunofluorescence confocal microscopy in the presence or absence of 1 μmol/L rociletinib. All experiments were repeated at least three times, and representative images and densitometry results were shown in each panel.