Endocrine Abstracts

The neural crest-derived, catecholamine-secreting tumors pheochromocytomas and paragangliomas are genetically heterogeneous. More than one-third of these tumors result from germline mutations in one of at least ten genes that belong to a variety of functional classes. Characterization of the molecular signals transduced by these genes and their respective mutants has enhanced our understanding of kinase signaling pathways, hypoxia regulation, and the link between metabolic disruptions and cell growth. The three most recent members of the pheochromocytoma/ paraganglioma susceptibility gene family add to this complexity: SDHA, a member of the succinate dehydrogenase complex, TMEM127, a three-spanner transmembrane protein with no recognizable functional motifs, and MAX, a transcription factor of the MYC family, respectively. In vitro and patient data indicate that these pathways intersect to delineate specific transcriptional signatures that uncover unsuspected associations between the signals associated with these gene products. In particular, preliminary data support a role for TMEM127 in the endosomal system and the mechanistic target of rapamycin [formerly mammalian target of rapamycin (mTOR)] pathway. Functional characterization of these susceptibility genes and discovery of additional pheochromocytoma/paraganglioma susceptibility genes is likely to shed light on our understanding of these tumors and extend these insights to other cancers.

Declaration of interest: There is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.

Funding: No specific grant from any funding agency in the public, commercial or not-for-profit sector.