HDAC9 and neuroblastoma: Lastly, we measured the HDAC9 expression of GBM cells by quantitative real time-PCR and western blot assay, and we found that HDAC9 was commonly expressed in GBM cell lines (A172, U-87 MG, LN229) and primary GBM cells from T0807 and T1018 specimen, but it was low expressed in neuroblastoma cell lines (Figure 1E, 1F).