For example, in the p16Ink4a knockout RCAS PDGFB/Nestin-tvA glioma mouse model, the downregulation of PTPRD promoted cell proliferation, whereas restoring PTPRD expression in GBM cells resulted in the suppression of cell growth and the induction of apoptosis [39,40]. The gene discussed is PDGFB; the disease is central nervous system cancer.