HDAC2 and neoplasm: To explore TAGLN and HDAC2 expression in GBM patient surgical specimens, we performed IHC staining and observed that HDAC2 (which is a hypoxia‐related gene), TAGLN, CA9 (a hypoxic marker), and HIF1α were all located in GBM tumor cell nuclei and highly expressed in pseudopalisades (upper) (Figure 6I; Figure S6J,K, Supporting Information).