TGFB1 and glioblastoma: By examining the genes differentially expressed between the two identified subgroups of glioblastomas that showed different TGFβ transcriptional responses, we found that the ligands TGFB1, TGFB2 and their receptors were expressed significantly higher in the strong TGFβ response group (Additional file 3) compared to those in the weak TGFβ response group, suggesting that increased expression of the ligands and receptors contributed to TGFβ activation.