The PC-12 rat pheochromocytoma, SK-N-SH and SK-N-BE(2)C human neuroblastoma cell lines all stabilise and activate both HIF-1α and HIF-2α protein endogenously in hypoxia [41], [42], and are derived from tumours of the sympathetic nervous system. The gene discussed is EPAS1; the disease is hereditary pheochromocytoma-paraganglioma.