mRNA and protein is differentially expressed in clinical medulloblastoma samples. a scatter plot of mRNA expression of HDAC1, 2 and 3, as measured by gene expression profiling. Only HDAC2 is elevated in in the subgroups with poor prognosis (SHH, Group 3 and Group 4), but not in the subgroup with good prognosis (WNT) or normal cerebellum. b HDAC2 protein expression is detected by immunohistochemistry (IHC) (brown staining) in the majority of medulloblastoma tumor samples. Both positive (sample 1, molecular subgroup: group 3) and negative (sample 2, molecular subgroup: SHH) examples are shown. No HDAC2 protein expression is detected by IHC in normal cerebellum in the two samples analyzed (depicted region: molecular layer of the hemisphere). Scale bar size: 50 μm. c Semiquantitative analysis of HDAC2 IHC reveals higher expression of HDAC2 protein in SHH, Group3 and Group4 compared to WNT and normal cerebellum. cb: cerebellum.