The majority of glioma samples in the current study were immunopositive for PI3K p110α (73% of all glioma and 83% of GBM), while detection of PI3K p110β expression by IHC was infrequent (n = 1) and detection of PI3K p110δ was not possible due to the lack of suitable antibodies. This evidence concerns the gene PIK3CD and central nervous system cancer.