Adverse Cell Culture Conditions Mimicking the Tumor Microenvironment Upregulate ABCG2 to Mediate Multidrug Resistance and a More Malignant Phenotype
Figure 4
Western blot analysis and flow cytometric assay showing a slight elevation of ABCG2 surface expression by 2-DG and hypoxic treatment in S1M1-80 cells. (a) Left panel: Western blot analysis showing ABCG2 protein expression in whole cell lysate obtained from S1M1-80 cells after the indicated treatment; right panel: relative ABCG2 protein expression based on densitometric analysis of Western blot images. (b) Flow cytometry-based cell surface ABCG2 staining. S1M1-80 cells were exposed to 2-DG (20 mM) or hypoxia for 16 h, after which they were incubated with anti-ABCG2 antibody (5D3) (denoted by the solid black line) or a negative control antibody (denoted by the grey-filled histogram). Fluorescence was then determined by flow cytometry. Δchannel # represents the difference in fluorescence signal between the specific ABCG2 antibody staining and the isotype antibody control. Representative histograms from one of three independent experiments are shown.
