All the benign cell lines (RC-165N/hTERT, PNT1A, PNT2-C2, BPH-1) and 3 of the cancer cell lines (Bob, P4E6 and RC-92a/hTERT), analysed for CD133 expression (by flow cytometry), contained CD133+ cells and had detectable levels of mRNA. The gene discussed is PROM1; the disease is cancer.