Using an antibody specifically recognizing EGFRvIII, Emlet, et al. showed that approximately 60% of primary glioblastomas are CD133+ and 70% EGFRvIII+: interestingly, the large majority (>80%) of CD133+ tumors are also EGFRvIII+ [26]. The gene discussed is PROM1; the disease is glioblastoma.