Fig. 4.

The sphere formation ability in vitro and tumorigenicity in vivo. a Representative images of sphere formation assay after culturing on low attachment dishes with serum-free medium for 10 days. b The number of spheres was counted under microscopy. The error bars indicate the standard error of the mean: SEM. Scale bars represent 100 μm. c Representative μCT images of mice 8 weeks after implantation and tumors derived from each cell group (dotted white line in upper panel). Photographs of representative mice and tumors (lower panel). d The tumorigenicity of the cells after implantation in the subcutaneous regions of immunodeficient nude mice. A total of 2 × 10⁶ cells were subcutaneously injected into flank of immunodeficient nude mice on day 13. The volume of the tumors was calculated by the formula 0.5 × (length) × (width)². The red bars indicate the median tumor volume. The error bars indicate the standard error of the mean: SEM. *P < 0.05