Interestingly, the HCMV-GB strains 6648 and 7220 that possess the more aggressive phenotype in CDX were isolated from glioblastoma with unmethylated MGMT promoter, meanwhile, HCMV-GB strain 9447 with a less aggressive phenotype in CDX was isolated from a glioblastoma patient with methylated MGMT promoter (Suppl. This evidence concerns the gene MGMT and glioblastoma.