Germline Mutations in the Mitochondrial 2-Oxoglutarate/Malate Carrier <i>SLC25A11</i> Gene Confer a Predisposition to Metastatic Paragangliomas

Abstract

Comprehensive genetic analyses have identified germline <i>SDHB</i> and <i>FH</i> gene mutations as predominant causes of metastatic paraganglioma and pheochromocytoma. However, some suspicious cases remain unexplained. In this study, we performed whole-exome sequencing of a paraganglioma exhibiting an <i>SDHx</i>-like molecular profile in the absence of <i>SDHx</i> or <i>FH</i> mutations and identified a germline mutation in the <i>SLC25A11</i> gene, which encodes the mitochondrial 2-oxoglutarate/malate carrier. Germline <i>SLC25A11</i> mutations were identified in six other patients, five of whom had metastatic disease. These mutations were associated with loss of heterozygosity, suggesting that <i>SLC25A11</i> acts as a tumor-suppressor gene. Pseudohypoxic and hypermethylator phenotypes comparable with those described in <i>SDHx</i>- and <i>FH</i>-related tumors were observed both in tumors with mutated <i>SLC25A11</i> and in <i>Slc25a11^Δ/Δ</i> immortalized mouse chromaffin knockout cells generated by CRISPR-Cas9 technology. These data show that <i>SLC25A11</i> is a novel paraganglioma susceptibility gene for which loss of function correlates with metastatic presentation.<b>Significance:</b> A gene encoding a mitochondrial carrier is implicated in a hereditary cancer predisposition syndrome, expanding the role of mitochondrial dysfunction in paraganglioma. <i>Cancer Res; 78(8); 1914-22. ©2018 AACR</i>.