Figure 1.

T24 sphere cells possessed bladder CIC properties. (a) T24 cells formed spheroid bodies 3 days after T24 cells were cultured in serum-free medium, scale bar=200 μm. (b) T24 sphere cells displayed stronger resistance to cytotoxic chemotherapy than T24 cells after treatment with 5-FU (100 μg/ml), etoposide (10 μg/ml), doxorubincin (1 μg/ml) and vinblastine (2 μg/ml) for 2 days. Cell viability was detected with MTT assay and repeated for three times. The relative cell viability was shown by fold change to the corresponding mock. (c) Upregulation of β-catenin, survivin and MRP1 in mRNA were found in T24 sphere cells. qRT-PCR data were normalized to GAPDH gene and are shown as fold change relative to T24 cells. (d) Protein level of survivin and Nanog increased in T24 sphere cells. (e) T24 sphere cells formed smaller colonies by crystal violet staining. (f) T24 sphere initiated tumor earlier than T24 cells (1 × 10³ cells per mouse). Incidence indicated the number of mice with palpable tumor. (g, h) Tumor growth curve and pictures showed that T24 sphere formed larger xenografts than T24. All data shown represent mean±S.D. (n=3). The number of mice in each group were three. **P<0.01, ***P<0.001