The frequency of PIK3R1Met326Ile in glioblastoma was significantly higher in the CCN1 high expression group (10/37 cases, 27.0%) than the CCN1 low expression group (3/38 cases, 7.9%) (p = 0.036, Fisher’s exact test) (Fig. 3A and B). The gene discussed is CCN1; the disease is glioblastoma.