Clinical and molecular progress in hereditary paraganglioma

Area of Science:

• Biochemistry
• Genetics
• Oncology

Background:

• Hereditary paraganglioma (PGL) involves genetic predisposition to vascular tumors.
• Germline mutations in succinate dehydrogenase (SDH) subunits (SDHB, SDHC, SDHD) cause PGL.
• SDH mutations are found in various PGL and pheochromocytoma subtypes.

Purpose of the Study:

• To explore the role of SDH mutations in PGL pathogenesis.
• To investigate the link between SDH mutations and hypoxia signaling pathways.
• To identify remaining knowledge gaps in PGL development.

Main Methods:

• Review of genetic and structural models of SDH function.
• Analysis of existing data on SDH mutation frequencies in different PGL types.
• Discussion of proposed mechanisms involving succinate and reactive oxygen species (ROS).

Main Results:

• SDH mutations are implicated in at least 11% of non-familial head and neck paragangliomas.
• SDH mutations are found in 8% of non-familial pheochromocytomas and 28% of malignant pheochromocytomas.
• PGL mutations are increasingly linked to constitutive activation of hypoxia signaling pathways.

Conclusions:

• SDH mutations may lead to succinate and ROS accumulation, activating hypoxia-inducible pathways.
• The precise mechanisms of ROS accumulation and SDH's role in oxygen homeostasis require further investigation.
• Understanding PGL pathogenesis necessitates further research into SDHD imprinting and SDH function.