CD4 and glioblastoma: Recently, it has been demonstrated that tumor-bearing hosts down-regulate miR-17-92 in CD4+ T cells, and it has been postulated that a type-2-skewing tumor microenvironment induces the down-regulation of miR-17-92 expression in T cells; CD4+ T cells from patients with glioblastoma multiforme had extremely low levels of 17-92 polycistronic miRNAs [33], suggesting the possibility that the low plasma miR-17-92 level in lymphoma patients may reflect miR-17-92 levels in host T cells.