While purified CD133-positive recruited cells could not give rise to transplanted gliomas at 10,000 cells (0/24 cases), and progeny cells did not robustly form tumors with cell numbers less than 3,000 (3/20 cases), addition of 10,000 CD133-positive recruited cells to 1,000 eGFP-positive progeny resulted in robust gliomagenesis (Figure 6i). This evidence concerns the gene PROM1 and central nervous system cancer.