PTGS2 and anaplastic astrocytoma: The validation qRT‐PCR of selected M/M polarization markers (CCL2, TLR2, IL1B, MRC1, CD14, CD163, PTGS2, MSR1, CD163L) in GAMs from eight GBM patients (n = 7 IDH1R132H‐non‐mutant, n = 1 IDH1R132H‐mutant) and one exemplary patient with IDH1R132H‐mutant anaplastic astrocytoma WHO grade III as compared to three different samples of WM microglia (Figure 1C) largely confirmed the microarray data.