Figure 3. Evaluation of the tumorigenicity of LC-CD133⁺ and LC-CD133⁻ in vivo.

(A) The in vivo tumorigenicity of LC-CD133⁺ and LC-CD133⁻ in tail vein-injected mice was analyzed by macroscopic and histological examination. A1–3: LC-CD133⁻; arrows: normal alveolar structure of lung. A4–6: LC-CD133⁺; arrows: tumor formation. A7–9: LC-CD133⁺; arrows: neovascularity and thrombosis. Bar: 200 µm. (B) The in vivo tumor-restoration and proliferative ability of 10⁴ LC-CD133⁺, 10⁵ LC-CD133⁻ and 5×10⁵ total tumor cells from patient No. 1, 2, 4, and 7 were examined by xenotransplanted tumorigenicity analysis. (C) The tumor repopulation ability of LC-CD133⁺ was studied in transplanted SCID mice. The expression levels of CD133 were determined by FACS analysis from primary LC-CD133⁺, second tumor, and third tumor. Data shown here are the mean±SD of three experiments.