SDHB (Succinate Dehydrogenase B) [SDHB/2382]

Succinate dehydrogenase (SDH) is Complex II in the mitochondria, vital for mitochondrial electron transport, as well as Krebs cycle function. SDH catalyzes the oxidation of succinate to fumarate and transfers electrons to ubiquinone through the coordination of its four subunits (SDHA, SDHB, SDHC, and SDHD). The SDH complex functions as a tumor suppressor. Loss of any subunit proteins lead to destabilization of the complex and tumor formation. SDH subunit B (SDHB) is ubiquitously expressed in normal tissues. Germline mutations in SDHB, SDHC, or SDHD genes predispose development of phaeochromocytoma, paraganglioma and gastrointestinal stromal tumor (GIST). SDHB immunohistochemistry is helpful in the identification of phaeochromocytomas, paragangliomas or GIST with SDHB mutation.