TNF and hereditary pheochromocytoma-paraganglioma: In human HeLa epithelial cells, human lymphoid U937 and murine neuroblastoma × rat glioma NG108-15 and rat PC12 pheochromocytoma, apoptosis was initiated by the use of staurosporine (STS) a known mitochondrial apoptosis inducer or inducer-mediated inducer of apoptosis, tumor necrosis factor α plus cycloheximide (TNF/CHX) [15,64,65].