PDGFRA and glioma: In both data sets, the expression of PDGFRA was enriched in low-grade (grade II) gliomas compared to high-grade (grades III and IV) gliomas (p<0.001 and p = 0.002 in GSE16011 and Rembrandt, respectively, t test, Figure 1A, 1B, 1C, 1D).