REST targets include a large number of genes and accumulated studies revealed that REST plays diverse roles in multiple cellular processes [6], it was originally discovered to repress neuron-specific genes in non-neuronal tissues and neural progenitors, and it was implicated as a tumor suppressor in breast cancer, colorectal cancer and small cell lung cancer, and as an oncogene in neuroblastomas, medulloblastomas and pheochromocytomas [7,8]. This evidence concerns the gene REST and pheochromocytoma.