CDK4 and glioblastoma: Combination therapy using mTOR and MEK inhibitors shows the most effective inhibition of PT and PTN growth, while CDK4/6 inhibitors compromise mTOR inhibitor effects in PTCC organoids (Supplementary Fig. 6 h), suggesting that CDK4/6 inhibitors should be carefully examined before being considered for treating GBM patients with CDKN2A/2B mutations.