Expression of stem cell markers. (A) Analysis of CD44 and CD24 expression in H1650 and H1650-ER1 cells by flow cytometry. (B) Flow cytometric analysis of CD133, SSEA-3, SSEA-4, Tra-1-60, and Tra-1-81 expression in H1650 and H1650-ER1 cells. Quantification of cells staining positively for different markers. The error bars represent s.e.m. (n = 3). H1650-ER1 cells were enriched for CD133+, SSEA-3+, SSEA-4+, and Tra-1-60+ populations as compared to parental H1650 cells (p-value < 0.05). No differential expression between H1650 and H1650-ER1 cells was observed for Tra-1-81. (C) mRNA expression of OCT3/4, NANOG, SOX-2, and ID2 in H1650 and H1650-ER1 cells was measured by quantitative RT-PCR. Fold change expression was normalized with respect to H1650 cells. The error bars represent s.e.m. (n = 3).