HDAC inhibitor treatment upregulates Notch1 in pheochromocytoma cells. Treatment for 2 days with increasing concentrations of VPA and SBHA increases the amount of active, cleaved Notch1 protein (NICD). The downstream target achaete scute complex-like 1 (ASCL1) also decreased with treatment. GAPDH is shown as a loading control. VPA, valproic acid, SBHA, suberoyl bis-hydroxamic acid, GAPDH, glyceraldehyde 3-phosphate dehydrogenase.