PTEN and glioblastoma: Subsequently, Takashi Shingu and colleagues established the first mouse model of QKI-deficient GBM, demonstrating that the co-deletion of Pten, p53, and QKI in mice NSCs (neural stem cells) resulted in 92% malignant glial tumors, which closely resemble human glioblastoma in terms of morphology, metastasis, proliferation, and heterogeneity.