Dataset Information

Prevalence of germline mutations in patients with pheochromocytoma or abdominal paraganglioma and sporadic presentation: a population-based study in Western Sweden.

ABSTRACT:

Background

Germline mutations in the susceptibility genes RET, SDHB, SDHD, and VHL have been reported in 7.5-24% of patients with pheochromocytoma (Pheo) or paraganglioma (PGL) and sporadic presentation. The purpose of the present study was to establish population-based data on the frequency of germline mutations in patients with apparently sporadic Pheo or abdominal PGL in Western Sweden.

Methods

From the Swedish National Cancer Registry, all patients with Pheo or PGL in Western Sweden (population 1.72 million) registered between 1958 and 2009 were identified (n = 256). Patients were characterized using register data, hospital records, and clinical interviews. All living patients with Pheo or abdominal PGL and sporadic presentation (n = 81) were invited to genetic screening; 71 patients accepted. Germline mutations were investigated by using direct sequencing for point mutations in RET, SDHB, SDHD, and VHL, and multiplex ligation-dependent probe amplification for gross deletions in SDHB, SDHC, SDHD, and VHL. Plasma or urinary metanephrines and/or urinary catecholamines were used for biochemical follow-up.

Results

The prevalence of germline mutations was 5.6%. Mutations were only seen in RET (n = 1) and SDHB (n = 3). Notably, in the patients with SDHB mutations, no malignant phenotype was observed during a mean follow-up of 23.3 years.

Conclusions

The frequency of germline mutations in patients with apparently sporadic Pheo and abdominal PGL in Western Sweden was lower than in previous studies. Variations in reported frequencies of germline mutations in patients with clinically sporadic Pheo/PGL may reflect geographical differences or patient selection.

SUBMITTER: Muth A

PROVIDER: S-EPMC3348434 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature

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Publications

Prevalence of germline mutations in patients with pheochromocytoma or abdominal paraganglioma and sporadic presentation: a population-based study in Western Sweden.

Muth Andreas A Abel Frida F Jansson Svante S Nilsson Ola O Ahlman Håkan H Wängberg Bo B

World journal of surgery 20120601 6

<h4>Background</h4>Germline mutations in the susceptibility genes RET, SDHB, SDHD, and VHL have been reported in 7.5-24% of patients with pheochromocytoma (Pheo) or paraganglioma (PGL) and sporadic presentation. The purpose of the present study was to establish population-based data on the frequency of germline mutations in patients with apparently sporadic Pheo or abdominal PGL in Western Sweden.<h4>Methods</h4>From the Swedish National Cancer Registry, all patients with Pheo or PGL in Western ...[more]

PMID: 22270996

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Project description:Identification of additional cancer-associated genes and secondary mutations driving the metastatic progression in pheochromocytoma and paraganglioma (PPGL) is important for subtyping, and may provide optimization of therapeutic regimens. We recently reported novel recurrent nonsynonymous mutations in the MYO5B gene in metastatic PPGL. Here, we explored the functional impact of these MYO5B mutations, and analyzed MYO5B expression in primary PPGL tumor cases in relation to mutation status. Immunohistochemistry and mRNA expression analysis in 30 PPGL tumors revealed an increased MYO5B expression in metastatic compared to non-metastatic cases. In addition, subcellular localization of MYO5B protein was altered from cytoplasmic to membranous in some metastatic tumors, and the strongest and most abnormal expression pattern was observed in a paraganglioma harboring a somatic MYO5B:p.G1611S mutation. In addition to five previously discovered MYO5B mutations, the present study of 30 PPGL (8 previous and 22 new samples) also revealed two, and hence recurrent, mutations in the gene paralog MYO5A. The three MYO5B missense mutations with the highest prediction scores (p.L587P, p.G1611S and p.R1641C) were selected and functionally validated using site directed mutagenesis and stable transfection into human neuroblastoma cells (SK-N-AS) and embryonic kidney cells (HEK293). In vitro analysis showed a significant increased proliferation rate in all three MYO5B mutated clones. The two somatically derived mutations, p.L587P and p.G1611S, were also found to increase the migration rate. Expression analysis of MYO5B mutants compared to wild type clones, demonstrated a significant enrichment of genes involved in migration, proliferation, cell adhesion, glucose metabolism, and cellular homeostasis. Our study validates the functional role of novel MYO5B mutations in proliferation and migration, and suggest the MYO5-pathway to be involved in the malignant progression in some PPGL tumors.

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Dataset Information

Prevalence of germline mutations in patients with pheochromocytoma or abdominal paraganglioma and sporadic presentation: a population-based study in Western Sweden.

Background

Methods

Results

Conclusions

Publications

Prevalence of germline mutations in patients with pheochromocytoma or abdominal paraganglioma and sporadic presentation: a population-based study in Western Sweden.

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