In 2023, Junyu Xu et al. reported a series of novel pyrimidin-2-amine compounds for the treatment of glioblastoma (GBM), among which LH20 (49, Figure 9) can inhibit the activity of CDK4 and CDK6 and reduce the phosphorylation of Rb [63]. This evidence concerns the gene CDK4 and glioblastoma.