PROM1 and glioblastoma: The presence of TAMRA+/CD133+ cells in the population of U87 glioblastoma cells in vitro and their in vivo tumorigenicity upon transplantation into immunodeficient mice have allowed the use of this cell line as a reliable and convenient model for the stated purposes of determining the therapeutic scheme and estimating its efficacy in curing this particular glioblastoma.