Telomerase reverse transcriptase promoter hypermethylation is associated with metastatic disease in abdominal paraganglioma

Telomere maintenance, a hallmark of cancer for cell immortalization, is commonly achieved by telomerase activation through induction of the telomerase reverse transcriptase (TERT) gene. Pheochromocytomas (PCC) and abdominal paragangliomas (PGL) (together PPGL) are endocrine tumours for which TERT promoter mutations and telomerase activation have been previously reported [1]. Only 10-15% of PPGL metastasize, however in the absence of metastases, the identification of malignant disease is a diagnostic dilemma. Over 30% of PPGL exhibit a constitutional mutation in one of 14 susceptibility genes, and additionally, recurrent somatic mutations occur frequently [2]. Mutations in VHL, SDHx and EPAS1 define the Cluster 1 mRNA expression profile with pseudo-hypoxic effects, and mutations in HRAS, MAX, NF1, RET and TMEM127 define Cluster 2 with activation of kinase-signaling pathways [2]. This article is protected by copyright. All rights reserved.