HDAC9 and glioma: HDAC inhibitors such as VPA are effective at inducing cell death in glioma cells and increase AIF expression, suggesting inactivation of the BNIP3 repressor activity.29 Furthermore, DR5 expression is increased by HDAC inhibitors.44 These studies indicate that DR5 expression is dynamically regulated and BNIP3 has a role in controlling DR5 expression in glioma cells and astrocytes.