Figure 8
Expression levels of ABCG2. The expression levels of ABCG2 mRNA ( A ) and protein ( B to D ) were examined with semi-quantitative RT-PCR and flow cytometry, respectively. B and C, representative flow cytometry histograms of SK-HEP-1 and SK-sphere cells, respectively. Black and gray histograms represent cells stained with PE-conjugated anti-ABCG2 and isotype control antibodies, respectively. D, bar-chart summarized from independent flow cytometric experiments. **P < 0.05 with the Mann-Whitney U-test.