RB1 and glioblastoma: For example, the CKI, roscovitine, sensitized glioblastoma cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis in vitro by targeting CDK2/cyclin B, E or A complexes [24] and milciclib inhibited cell proliferation, downregulated CDK4/Rb transduction pathway markers, and induced cell death by autophagy through inhibition of CDK2/cyclin A, CDK7/cyclin H and CDK4/cyclin D1 complexes in glioblastoma cells [25].