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Radomska K, Leszczyńska Z, Becht R, Zaborek-Łyczba M, Rzepakowska A, Lubiński J, Szymański M. Algorithm of genetic diagnosis for patients with head and neck paraganglioma-update. Front Neurol 2024; 15:1437027. [PMID: 39268066 PMCID: PMC11390439 DOI: 10.3389/fneur.2024.1437027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Accepted: 07/18/2024] [Indexed: 09/15/2024] Open
Abstract
Paragangliomas are rare tumors originating from the paraventricular bodies of the autonomic nervous system located in the adrenal glands, chest, abdomen, pelvis and head and neck. Tumors of this type account for 0.5% of head and neck cancers, 0.03% of all cancers and their incidence is estimated at 1-30/100,000 per year. Head and Neck Paragangliomas (HNPGL) are localized in carotid body, tympanic cavity or jugular foramen. It is established that HNPGL may be associated with mutations of the SDH complex, with SDHD being the most prevalent. However, SDHB, SDHC and SDHAF are also potential causes. The aforementioned mutations are influenced by various risk factors, including young age, a positive family history of paraganglioma, the presence of metastases and gender The purpose of this study is to summarize the results of genetic testing performed on patients with head and neck paraganglioma and to create an up-to-date genetic diagnosis algorithm for patients with HNPGL based on previous studies published in the literature that can be used in daily practice. Several papers observed that among SDHD mutation carriers, most or all of those studied had HNPGL, and SDHB mutations were more frequently found in the presence of metastasis. Based on the results, it was concluded that there is no basis for genetic testing for VHL in patients without a positive family history. In each algorithm proposed by different authors, proposals for rational genetic diagnosis were analyzed based on the studies cited by the author and the analyses included in our paper. For the analysis of the treatment algorithms, the following were included: Martin, Mannelli, Neumann, Gupta. Subsequently, publications related to the genetic diagnosis of HNPGL were analyzed to verify the proposed algorithms in light of the latest genetic studies and to establish an updated diagnostic management scheme.
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Affiliation(s)
- Katarzyna Radomska
- Department of Otolaryngology, Pomeranian Medical University, Szczecin, Poland
| | - Zofia Leszczyńska
- Department of Otolaryngology, Pomeranian Medical University, Szczecin, Poland
| | - Rafal Becht
- Department of Oncology, Pomeranian Medical University, Szczecin, Poland
| | | | - Anna Rzepakowska
- Department of Otolaryngology, Medical University of Warsaw, Warsaw, Poland
| | - Jakub Lubiński
- Department of Otolaryngology, Pomeranian Medical University, Szczecin, Poland
| | - Marcin Szymański
- Department of Otolaryngology, Medical University of Lublin, Lublin, Poland
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Cardot-Bauters C, Vantyghem MC, Do Cao C, Desailloud R, Joubert M, Coppin L, Odou MF, Pigny P. Genetic predisposition to pheochromocytoma and paraganglioma: 21 years of experience in the field. ANNALES D'ENDOCRINOLOGIE 2024; 85:276-283. [PMID: 38815921 DOI: 10.1016/j.ando.2024.05.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 04/20/2024] [Accepted: 05/04/2024] [Indexed: 06/01/2024]
Abstract
CONTEXT Pheochromocytoma and paraganglioma (PPGL) are rare neuroendocrine tumors with high heritability, justifying systematic genetic screening for a germline variant in one of the twenty predisposing genes described to date. PURPOSE To describe the experience of one endocrine oncogenetic laboratory over a period of 21 years (2001-2022), from the beginning of PPGL genotyping with Sanger sequencing in 2001 to the implementation of next-generation sequencing (NGS). METHOD The activity database of an academic oncogenetic laboratory was searched to extract patients/relatives identified with a pathogenic variant/likely pathogenic variant (PV/LPV) over a period of 21 years. Clinical and genetic data were compared. RESULTS In total, 606 index cases with PPGL and 444 relatives were genotyped. Genotyping of index cases was performed by Sanger sequencing and gene deletion analysis in 327 cases and by NGS in 279. Germline PV/LPV spanning 10 genes was identified in 165 index cases (27.2%). Several recurrent PV/LPVs in SDHx were observed in non-related index cases, the most frequent being SDHD, c.170-1G>T (n=28). This subgroup showed great phenotypic variability both between and within families in terms of both tumor location and number. Four patients (1.1%) with PV/LPV in SDHx had 3PA (Pituitary Adenoma and pheochromocytoma/paraganglioma) syndrome. 258 relatives (58.1%) had inherited a PV/LPV in one driver gene. The rate of PV/LPV carriers who were symptomatic at first imaging evaluation was 32%, but varied between<20% in SDHB and SDHC and >50% in SDHD, VHL and MAX. CONCLUSION Our experience confirmed previously established genotype-phenotype correlations, but also highlights atypical clinical presentations, even for the same genetic variant. These data must be taken into account for optimal patient follow-up and management.
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Affiliation(s)
- Catherine Cardot-Bauters
- Service d'endocrinologie, diabétologie-métabolisme, hôpital Claude-Huriez, CHU, 59037 Lille cedex, France
| | - Marie-Christine Vantyghem
- Service d'endocrinologie, diabétologie-métabolisme, hôpital Claude-Huriez, CHU, 59037 Lille cedex, France
| | - Christine Do Cao
- Service d'endocrinologie, diabétologie-métabolisme, hôpital Claude-Huriez, CHU, 59037 Lille cedex, France
| | - Rachel Desailloud
- Service d'endocrinologie-diabétologie, nutrition, hôpital Sud nord, CHU, 80054 Amiens cedex 1, France
| | - Michael Joubert
- Service d'endocrinologie, CHU Côte de Nacre, 14000 Caen cedex, France
| | - Lucie Coppin
- Laboratoire de biochimie « hormonologie-métabolisme-nutrition-oncologie », UF oncogénétique moléculaire, laboratoire de biologie médicale de référence, CHU de Lille, 59037 Lille cedex, France; Inserm UMR 1277, CANTHER, université de Lille, 59045 Lille cedex, France
| | - Marie-Francoise Odou
- Laboratoire de biochimie « hormonologie-métabolisme-nutrition-oncologie », UF oncogénétique moléculaire, laboratoire de biologie médicale de référence, CHU de Lille, 59037 Lille cedex, France; Inserm, CHU Lille, U1286 - Infinite, université de Lille, 59045 Lille cedex, France
| | - Pascal Pigny
- Laboratoire de biochimie « hormonologie-métabolisme-nutrition-oncologie », UF oncogénétique moléculaire, laboratoire de biologie médicale de référence, CHU de Lille, 59037 Lille cedex, France; Inserm UMR 1277, CANTHER, université de Lille, 59045 Lille cedex, France.
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3
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de Bresser CJM, Petri BJ, Braat AJAT, de Keizer B, van Treijen MJC, Dankbaar JW, Pameijer FA, Kok MGJ, de Ridder M, van Nesselrooij BPM, de Bree R, de Borst GJ, Rijken JA. The Additional Value of Somatostatin Receptor Positron Emission Computed Tomography ([ 68Ga]Ga-DOTATOC PET/CT) Compared with Magnetic Resonance Imaging of the Head and Neck Region in Paraganglioma Patients: A Pilot Study. Cancers (Basel) 2024; 16:986. [PMID: 38473347 DOI: 10.3390/cancers16050986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 02/20/2024] [Accepted: 02/24/2024] [Indexed: 03/14/2024] Open
Abstract
The Dutch guideline for patients suspected of head and neck paragangliomas (HNPGLs) recommends magnetic resonance imaging (MRI) and/or computed tomography (CT) of the head and neck area. Additionally, it suggests considering additional nuclear imaging. The aim of this study was to evaluate the outcomes of [68Ga]Ga-DOTATOC PET/CT compared to MRI in patients with suspected HNPGLs and carriers of genetic variations. METHODS In this single-center pilot study, retrospective data were obtained from consecutive patients between 2016 and 2023. Both MRI and [68Ga]Ga-DOTATOC PET/CT were performed within 12 months. The primary outcome was the location of HNPGLs. RESULTS A total of 25 consecutive patients were included, and 7 patients (28.0%, p = 0.5) showed differences between the imaging modalities, of whom 5 patients had unexpected localizations with additional uptake by somatostatin receptors (SSTR) on the [68Ga]Ga-DOTATOC PET/CT. CONCLUSIONS The authors recommend performing baseline imaging with [68Ga]Ga-DOTATOC PET/CT (if available) in variant carriers and using MRI/CT for follow-up according to the regional protocol, thereby shifting the gold standard for baseline imaging from MRI/CT to [68Ga]Ga-DOTATOC PET/CT.
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Affiliation(s)
- Carolijn J M de Bresser
- Department of Vascular Surgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
| | - Bart-Jeroen Petri
- Department of Vascular Surgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
| | - Arthur J A T Braat
- Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
- Department of Nuclear Medicine, Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
| | - Bart de Keizer
- Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
| | - Mark J C van Treijen
- Department of Endocrine Oncology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
| | - Jan Willem Dankbaar
- Department of Radiology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
| | - Frank A Pameijer
- Department of Radiology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
| | - Marius G J Kok
- Department of Radiology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
- Department of Radiology, Medical Spectrum Twente, 7512 KZ Enschede, The Netherlands
| | - Mischa de Ridder
- Department of Radiotherapy, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
| | | | - Remco de Bree
- Department of Head and Neck Surgical Oncology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
| | - Gert J de Borst
- Department of Vascular Surgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
| | - Johannes A Rijken
- Department of Head and Neck Surgical Oncology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
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Bancel LP, Masso V, Dessein AF, Aubert S, Leteurtre E, Coppin L, Odou MF, Cao CD, Cardot-Bauters C, Pigny P. Serum Succinate/Fumarate Ratio in Patients With Paraganglioma/Pheochromocytoma Attending an Endocrine Oncogenetic Unit. J Clin Endocrinol Metab 2023; 108:2343-2352. [PMID: 36848172 DOI: 10.1210/clinem/dgad109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 01/27/2023] [Accepted: 02/22/2023] [Indexed: 03/01/2023]
Abstract
CONTEXT Pheochromocytomas and paragangliomas (PPGLs) with SDHx pathogenic variants (PVs) are characterized by a higher intratissular succinate/fumarate ratio (RS/F) than non-SDHx-mutated ones. Also, an increase in serum succinate levels has been reported in patients with germline SDHB or SDHD PV. OBJECTIVE To assess whether measurement of serum succinate, fumarate levels, and RS/F might aid identification of an SDHx germline PV/likely pathogenic variant (LPV) in patients with PPGL or in asymptomatic relatives; and to guide identification of a PV/LPV among the variants of unknown significance (VUS) identified in SDHx by next-generation sequencing. METHODS This prospective monocentric study included 93 patients attending an endocrine oncogenetic unit for genetic testing. Succinate and fumarate were measured in serum by gas chromatography coupled to mass spectrometry. The RS/F was calculated to assess SDH enzymatic function. Diagnostic performance was assessed by receiver operating characteristic analysis. RESULTS RS/F had a higher discriminant power than succinate alone to identify an SDHx PV/LPV in patients with PPGL. However, SDHD PVs/LPVs are frequently missed. Only RS/F differed between asymptomatic SDHB/SDHD PV/LPV carriers and SDHB/SDHD-linked patients with PPGL. Finally RS/F could be helpful to easily evaluate the functional impact of VUS in SDHx. CONCLUSION Measurement of serum RS/F in patients with PPGL and in asymptomatic relatives is a valuable initial workup tool to detect those carrying a germline PV/LPV in SDHx. Its discriminative power is equal or superior to those of succinate measured alone. SDHD PVs/LPVs are less frequently identified by these biochemical tools. Use of RS/F for SDHx VUS reclassification needs to be evaluated further.
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Affiliation(s)
- Léo-Paul Bancel
- CHU Lille, Laboratoire de Biochimie-Hormonologie, Métabolisme, Nutrition, Oncologie, Centre de Biologie Pathologie, F.59037 Lille Cedex, France
| | - Vincent Masso
- CHU Lille, Laboratoire de Biochimie-Hormonologie, Métabolisme, Nutrition, Oncologie, Centre de Biologie Pathologie, F.59037 Lille Cedex, France
| | - Anne-Frederique Dessein
- CHU Lille, Laboratoire de Biochimie-Hormonologie, Métabolisme, Nutrition, Oncologie, Centre de Biologie Pathologie, F.59037 Lille Cedex, France
| | - Sébastien Aubert
- CHU Lille, Service d'Anatomie Pathologique, Centre de Biologie Pathologie, F-59037 Lille Cedex, France
| | - Emmanuelle Leteurtre
- University of Lille, CNRS, Inserm, CHU Lille, UMR9020-U1277-CANTHER-Cancer Heterogeneity, Plasticity and Resistance to therapies, F-59000 Lille, France
| | - Lucie Coppin
- CHU Lille, Laboratoire de Biochimie-Hormonologie, Métabolisme, Nutrition, Oncologie, Centre de Biologie Pathologie, F.59037 Lille Cedex, France
| | - Marie-Françoise Odou
- CHU Lille, Laboratoire de Biochimie-Hormonologie, Métabolisme, Nutrition, Oncologie, Centre de Biologie Pathologie, F.59037 Lille Cedex, France
| | - Christine Do Cao
- CHU Lille, Service d'Endocrinologie, Diabétologie, Métabolisme, Nutrition, Hôpital Claude Huriez, F-59037 Lille Cedex, France
| | - Catherine Cardot-Bauters
- CHU Lille, Service d'Endocrinologie, Diabétologie, Métabolisme, Nutrition, Hôpital Claude Huriez, F-59037 Lille Cedex, France
| | - Pascal Pigny
- CHU Lille, Laboratoire de Biochimie-Hormonologie, Métabolisme, Nutrition, Oncologie, Centre de Biologie Pathologie, F.59037 Lille Cedex, France
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Foley M, Sharma A, Garfield K, Maese L, Buchmann L, Boyle J, Kohlmann W, Jeter J, Greenberg S. A need to tailor surveillance based on family history: describing a highly penetrant familial paraganglioma kindred with an SDHD pathogenic variant. Fam Cancer 2023; 22:217-224. [PMID: 36223042 DOI: 10.1007/s10689-022-00318-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 10/05/2022] [Indexed: 11/29/2022]
Abstract
Pathogenic variants (PVs) in the SDHD gene increase risk for paragangliomas (PGL)/pheochromocytomas, renal cell carcinomas, and gastrointestinal stromal tumors. Penetrance in individuals with SDHD PVs varies in reported research from 40-70%, and there is limited evidence of specific genotype risks. This study aims to characterize a multi-generational family with SDHD p.Trp43* PVs and potential genotype-phenotype considerations for surveillance. Individuals with a paternally inherited SDHD p.Trp43*(c.129G > A) PV were identified. Genetic, medical and family histories were abstracted, including clinical characteristics, tumor histories, and treatment approaches. Eleven individuals with the SDHD PV in the same kindred were diagnosed with 41 SDHx-related tumors across all family members. Eight individuals developed 27 head and neck PGL of varying origins, and seven individuals developed tumors outside of the head and neck region. Many individuals had multiple tumors, and age of first tumor diagnosis ranged from age 10 to age 45 years old. Individuals with SDHD p.Trp43* variants may have higher risks for SDHx related tumors than other SDHD variants. Prioritizing identification of at-risk individuals and initiating surveillance tailored to family history is recommended given the rate of multiple tumors found in one familial branch of individuals under 18 years old. Individuals with strong family histories of PGL at young ages with this PV will benefit from tailored surveillance recommendations.
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Affiliation(s)
- Madeline Foley
- School of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Anu Sharma
- Department of Endocrinology, University of Utah, Salt Lake City, UT, USA
| | - Kinley Garfield
- Genetic Counseling Shared Resource, Huntsman Cancer Institute, Salt Lake City, UT, USA
| | - Luke Maese
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Luke Buchmann
- Division of Otolaryngology, University of Utah, Salt Lake City, UT, USA
| | - Julie Boyle
- Huntsman Cancer Institute, Bioinformatic Analysis Shared Resource, Salt Lake City, UT, USA
| | - Wendy Kohlmann
- Genetic Counseling Shared Resource, Huntsman Cancer Institute, Salt Lake City, UT, USA
| | - Joanne Jeter
- Division of Oncology, University of Utah, Salt Lake City, UT, USA
| | - Samantha Greenberg
- Genetic Counseling Shared Resource, Huntsman Cancer Institute, Salt Lake City, UT, USA.
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Bayley JP, Bausch B, Jansen JC, Hensen EF, van der Tuin K, Corssmit EP, Devilee P, Neumann HP. SDHB variant type impacts phenotype and malignancy in pheochromocytoma-paraganglioma. J Med Genet 2023; 60:25-32. [PMID: 34750193 DOI: 10.1136/jmedgenet-2020-107656] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 10/07/2021] [Indexed: 02/04/2023]
Abstract
BACKGROUND Traditional genotype-phenotype correlations for the succinate dehydrogenase-complex II (SDH) genes link SDHB variants to thoracic-abdominal pheochromocytoma-paraganglioma (PPGL) and SDHD variants to head and neck paraganglioma (HNPGL). However, in a recent study we found strong and specific genotype-phenotype associations for SDHD variants. In the present study we zoom in on the genotype-phenotype associations of SDHB gene variants, considering the impact of individual gene variants on disease risk and risk of malignancy. METHODS We analysed two large independent data sets, including a total of 448 patients with PPGL and HNPGL, and studied the association of missense or truncating SDHB variants with tumour incidence, age of onset and malignancy risk using binomial testing and Kaplan-Meier analysis. RESULTS Compared with missense variants, truncating SDHB variants were significantly and consistently more common in patients with PPGL, by a 20 percentage point margin. Malignancy was also significantly more common in truncating versus missense variant carriers. No overall differences in age of PPGL onset were noted between carriers of the two variant types, although some individual variants may differ in certain cases. Missense variants were marginally over-represented among patients with HNPGL, but the difference was not statistically significant. CONCLUSION SDHB truncating variants convey an elevated risk for development of both PPGL and malignancy compared with missense variants. These results further support earlier robust associations between truncating variants and PPGL, and also suggest that the two variant types differ in their impact on complex II function, with PPGL/HNPGL tissues displaying differing sensitivities to changes in complex II function.
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Affiliation(s)
- Jean Pierre Bayley
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Birke Bausch
- Department of Medicine II, University of Freiburg Faculty of Medicine, Freiburg, Germany
| | - Jeroen C Jansen
- Department of Otorhinolaryngology, Leids Universitair Medisch Centrum, Leiden, The Netherlands
| | - Erik F Hensen
- Department of Otorhinolaryngology - Head & Neck Surgery, VU Medisch Centrum, Amsterdam, The Netherlands.,Department of Otolaryngology - Head and Neck Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Karin van der Tuin
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Eleonora Pm Corssmit
- Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Peter Devilee
- Departments of Human Genetics and Pathology, Leiden University Medical Center, Leiden, The Netherlands
| | - Hartmut Ph Neumann
- Department of Nephrology, Universitätsklinikum Freiburg, Freiburg, Germany
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Ascher DB, Kaminskas LM, Myung Y, Pires DEV. Using Graph-Based Signatures to Guide Rational Antibody Engineering. Methods Mol Biol 2023; 2552:375-397. [PMID: 36346604 DOI: 10.1007/978-1-0716-2609-2_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Antibodies are essential experimental and diagnostic tools and as biotherapeutics have significantly advanced our ability to treat a range of diseases. With recent innovations in computational tools to guide protein engineering, we can now rationally design better antibodies with improved efficacy, stability, and pharmacokinetics. Here, we describe the use of the mCSM web-based in silico suite, which uses graph-based signatures to rapidly identify the structural and functional consequences of mutations, to guide rational antibody engineering to improve stability, affinity, and specificity.
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Affiliation(s)
- David B Ascher
- Structural Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Parkville, VIC, Australia
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
- Department of Biochemistry, Cambridge University, Cambridge, UK
- School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, Queensland, Australia
| | - Lisa M Kaminskas
- School of Biological Sciences, University of Queensland, St Lucia, QLD, Australia
| | - Yoochan Myung
- Structural Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Parkville, VIC, Australia
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
- School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, Queensland, Australia
| | - Douglas E V Pires
- Structural Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Parkville, VIC, Australia.
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.
- School of Computing and Information Systems, University of Melbourne, Parkville, VIC, Australia.
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Bayley JP, Devilee P. Hypothesis: Why Different Types of SDH Gene Variants Cause Divergent Tumor Phenotypes. Genes (Basel) 2022; 13:genes13061025. [PMID: 35741787 PMCID: PMC9222429 DOI: 10.3390/genes13061025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 06/01/2022] [Accepted: 06/02/2022] [Indexed: 11/16/2022] Open
Abstract
Despite two decades of paraganglioma-pheochromocytoma research, the fundamental question of how the different succinate dehydrogenase (SDH)-related tumor phenotypes are initiated has remained unanswered. Here, we discuss two possible scenarios by which missense (hypomorphic alleles) or truncating (null alleles) SDH gene variants determine clinical phenotype. Dysfunctional SDH is a major source of reactive oxygen species (ROS) but ROS are inhibited by rising succinate levels. In scenario 1, we propose that SDH missense variants disrupt electron flow, causing elevated ROS levels that are toxic in sympathetic PPGL precursor cells but well controlled in oxygen-sensing parasympathetic paraganglion cells. We also suggest that SDHAF2 variants, solely associated with HNPGL, may cause the reversal of succinate dehydrogenase to fumarate reductase, producing very high ROS levels. In scenario 2, we propose a modified succinate threshold model of tumor initiation. Truncating SDH variants cause high succinate accumulation and likely initiate tumorigenesis via disruption of 2-oxoglutarate-dependent enzymes in both PPGL and HNPGL precursor tissues. We propose that missense variants (including SDHAF2) cause lower succinate accumulation and thus initiate tumorigenesis only in very metabolically active tissues such as parasympathetic paraganglia, which naturally show very high levels of succinate.
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Affiliation(s)
- Jean-Pierre Bayley
- Department of Human Genetics, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands;
- Correspondence:
| | - Peter Devilee
- Department of Human Genetics, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands;
- Department of Pathology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
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Kuo MJM, Nazari MA, Jha A, Pacak K. Pediatric Metastatic Pheochromocytoma and Paraganglioma: Clinical Presentation and Diagnosis, Genetics, and Therapeutic Approaches. Front Endocrinol (Lausanne) 2022; 13:936178. [PMID: 35903274 PMCID: PMC9314859 DOI: 10.3389/fendo.2022.936178] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 06/13/2022] [Indexed: 12/18/2022] Open
Abstract
Although pediatric pheochromocytomas and paragangliomas (PPGLs) are rare, they have important differences compared to those in adults. Unfortunately, without timely diagnosis and management, these tumors have a potentially devastating impact on pediatric patients. Pediatric PPGLs are more often extra-adrenal, multifocal/metastatic, and recurrent, likely due to these tumors being more commonly due to a genetic predisposition than in adults. This genetic risk results in disease manifestations at an earlier age giving these tumors time to advance before detection. In spite of these problematic features, advances in the molecular and biochemical characterization of PPGLs have heralded an age of increasingly personalized medicine. An understanding of the genetic basis for an individual patient's tumor provides insight into its natural history and can guide clinicians in management of this challenging disease. In pediatric PPGLs, mutations in genes related to pseudohypoxia are most commonly seen, including the von Hippel-Lindau gene (VHL) and succinate dehydrogenase subunit (SDHx) genes, with the highest risk for metastatic disease associated with variants in SDHB and SDHA. Such pathogenic variants are associated with a noradrenergic biochemical phenotype with resultant sustained catecholamine release and therefore persistent symptoms. This is in contrast to paroxysmal symptoms (e.g., episodic hypertension, palpitations, and diaphoresis/flushing) as seen in the adrenergic, or epinephrine-predominant, biochemical phenotype (due to episodic catecholamine release) that is commonly observed in adults. Additionally, PPGLs in children more often present with signs and symptoms of catecholamine excess. Therefore, children, adolescents, and young adults present differently from older adults (e.g., the prototypical presentation of palpitations, perspiration, and pounding headaches in the setting of an isolated adrenal mass). These presentations are a direct result of genetic determinants and highlight the need for pediatricians to recognize these differences in order to expedite appropriate evaluations, including genetic testing. Identification and familiarity with causative genes inform surveillance and treatment strategies to improve outcomes in pediatric patients with PPGL.
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Affiliation(s)
- Mickey J. M. Kuo
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, United States
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Matthew A. Nazari
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Abhishek Jha
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Karel Pacak
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
- *Correspondence: Karel Pacak,
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Miller C, Pazderska A, Reynolds J, Gou P, Dunne B, McElhinney K, Owens L. Pheochromocytoma due to a novel SDHD variant presenting as unilateral visual loss. Endocrinol Diabetes Metab Case Rep 2021; 2021:EDM-21-0107. [PMID: 34866059 PMCID: PMC8686172 DOI: 10.1530/edm-21-0107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 11/02/2021] [Indexed: 11/13/2022] Open
Abstract
SUMMARY A 53-year-old female presented to a tertiary ophthalmology referral centre complaining of unilateral painless loss of vision. Subsequent assessment revealed malignant hypertension causing right-sided cystoid macular oedema. During the course of secondary hypertension workup, she was diagnosed with a 7.8 cm phaeochromocytoma which was resected. Testing for a panel of all predisposing phaeochromocytoma-causing variants using next-generation sequencing resulted in the diagnosis of a novel SDHD variant. LEARNING POINTS Screening for secondary causes of hypertension is indicated when there is evidence of hypertension-mediated end-organ damage (1). Testing for a predisposing variant should be considered in all patients with phaeochromocytoma or paraganglioma due to the high heritability rate and prevalence of somatic variants (2, 3, 4). Novel variants are commonly uncovered in the Succinate Dehydrogenase (SDH) subunit; proving pathogenicity is a complex, time-consuming process and one challenge of next-generation sequencing (3). SDHB immunohistochemistry as a tool for demonstrating pathogenicity is associated with reduced sensitivity when assessing SDHD variants (5, 6).
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Affiliation(s)
- Clare Miller
- Department of Endocrinology, St. James’s Hospital, Dublin, Ireland
| | | | - John Reynolds
- Department of Surgery, St. James’s Hospital, Dublin, Ireland
| | - Patricia Gou
- Department of Histopathology, St. James’s Hospital, Dublin, Ireland
| | - Barbara Dunne
- Department of Histopathology, St. James’s Hospital, Dublin, Ireland
| | - Kealan McElhinney
- Department of Ophthalmopathy, Royal Victoria Eye and Ear Hospital, Dublin, Ireland
| | - Lisa Owens
- Department of Endocrinology, St. James’s Hospital, Dublin, Ireland
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11
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Rodrigues CHM, Pires DEV, Ascher DB. mmCSM-PPI: predicting the effects of multiple point mutations on protein-protein interactions. Nucleic Acids Res 2021; 49:W417-W424. [PMID: 33893812 PMCID: PMC8262703 DOI: 10.1093/nar/gkab273] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/18/2021] [Accepted: 04/15/2021] [Indexed: 11/16/2022] Open
Abstract
Protein-protein interactions play a crucial role in all cellular functions and biological processes and mutations leading to their disruption are enriched in many diseases. While a number of computational methods to assess the effects of variants on protein-protein binding affinity have been proposed, they are in general limited to the analysis of single point mutations and have been shown to perform poorly on independent test sets. Here, we present mmCSM-PPI, a scalable and effective machine learning model for accurately assessing changes in protein-protein binding affinity caused by single and multiple missense mutations. We expanded our well-established graph-based signatures in order to capture physicochemical and geometrical properties of multiple wild-type residue environments and integrated them with substitution scores and dynamics terms from normal mode analysis. mmCSM-PPI was able to achieve a Pearson's correlation of up to 0.75 (RMSE = 1.64 kcal/mol) under 10-fold cross-validation and 0.70 (RMSE = 2.06 kcal/mol) on a non-redundant blind test, outperforming existing methods. Our method is freely available as a user-friendly and easy-to-use web server and API at http://biosig.unimelb.edu.au/mmcsm_ppi.
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Affiliation(s)
- Carlos H M Rodrigues
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Structural Biology and Bioinformatics, Department of Biochemistry and Pharmacology, University of Melbourne, Melbourne, Victoria, Australia
- Systems and Computational Biology, Bio21 Institute, University of Melbourne, Melbourne, Victoria, Australia
| | - Douglas E V Pires
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Structural Biology and Bioinformatics, Department of Biochemistry and Pharmacology, University of Melbourne, Melbourne, Victoria, Australia
- Systems and Computational Biology, Bio21 Institute, University of Melbourne, Melbourne, Victoria, Australia
- School of Computing and Information Systems, University of Melbourne, Melbourne, Victoria, Australia
| | - David B Ascher
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Structural Biology and Bioinformatics, Department of Biochemistry and Pharmacology, University of Melbourne, Melbourne, Victoria, Australia
- Systems and Computational Biology, Bio21 Institute, University of Melbourne, Melbourne, Victoria, Australia
- Department of Biochemistry, University of Cambridge, Cambridge, UK
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12
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Chatzikyriakou P, Touska P, Moonim MT, Obholzer R, Afridi S, Sandison A, Oakey RJ, Izatt L. Case report of a man with multiple paragangliomas and pathogenic germline variants in both NF1 and SDHD. Cancer Genet 2021; 256-257:110-114. [PMID: 34107390 DOI: 10.1016/j.cancergen.2021.05.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 05/10/2021] [Accepted: 05/20/2021] [Indexed: 11/24/2022]
Abstract
We report a novel case of multiple paragangliomas in a patient who was identified with pathogenic variants in both NF1 and SDHD genes. The proband is a man with known familial NF1 disease, diagnosed clinically in childhood. Multiple head and neck paragangliomas (HNPGL) were found during investigations for acute left sided neurological symptoms, in the region of his known plexiform neurofibroma. He was referred for genetic counselling. He underwent surgery to remove a left carotid body tumor (CBT). A pheochromocytoma and paraganglioma gene panel was tested. Blood and HNPGL tumor DNA were analyzed by whole exome sequencing. In addition to the NF1 truncating variant c.5107delA, p.(Ser1703AlafsTer7), the SDHD truncating pathogenic variant c.3G > A, p.(Met1?) was found. Tumor sequencing showed no LOH of SDHD or NF1, but monoallelic loss of 11p15 and 11q12.2-q12.3 was observed. Co-occurrence of pathogenic variants in multiple cancer susceptibility genes is rare but possible, identified by the increased use of panel testing. This is the first description of a patient presenting with NF1 and SDHD dual pathology, with HNPGL development due to SDHD. This case illustrates the central role of genetic sequencing in PPGLs and the strong genotype-phenotype correlations of different genes.
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Affiliation(s)
- Prodromos Chatzikyriakou
- Department of Medical and Molecular Genetics, King's College London, Guy's Hospital, London SE1 9RT, United Kingdom.
| | - Philip Touska
- Department of Radiology, Guy's and St Thomas' NHS Foundation Trust, London SE1 9RT, United Kingdom.
| | - Mufaddal T Moonim
- Cellular Pathology, Imperial College Healthcare Trust, London, United Kingdom.
| | - Rupert Obholzer
- Department of ENT and Skull Base Surgery, Guy's and St Thomas' NHS Foundation Trust, London SE1 9RT, United Kingdom.
| | - Shazia Afridi
- Department of Neurology, Guy's and St Thomas' NHS Foundation Trust, London SE1 9RT, United Kingdom.
| | - Ann Sandison
- Department of Head and Neck / Oral Pathology, Guy's and St Thomas' NHS Foundation Trust, London SE1 9RT, United Kingdom.
| | - Rebecca J Oakey
- Department of Medical and Molecular Genetics, King's College London, Guy's Hospital, London SE1 9RT, United Kingdom.
| | - Louise Izatt
- Department of Medical and Molecular Genetics, King's College London, Guy's Hospital, London SE1 9RT, United Kingdom; Department of Clinical Genetics, Guy's and St Thomas' NHS Foundation Trust, London SE1 9RT, United Kingdom.
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13
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Portelli S, Barr L, de Sá AG, Pires DE, Ascher DB. Distinguishing between PTEN clinical phenotypes through mutation analysis. Comput Struct Biotechnol J 2021; 19:3097-3109. [PMID: 34141133 PMCID: PMC8180946 DOI: 10.1016/j.csbj.2021.05.028] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 04/29/2021] [Accepted: 05/19/2021] [Indexed: 12/28/2022] Open
Abstract
Phosphate and tensin homolog on chromosome ten (PTEN) germline mutations are associated with an overarching condition known as PTEN hamartoma tumor syndrome. Clinical phenotypes associated with this syndrome range from macrocephaly and autism spectrum disorder to Cowden syndrome, which manifests as multiple noncancerous tumor-like growths (hamartomas), and an increased predisposition to certain cancers. It is unclear, however, the basis by which mutations might lead to these very diverse phenotypic outcomes. Here we show that, by considering the molecular consequences of mutations in PTEN on protein structure and function, we can accurately distinguish PTEN mutations exhibiting different phenotypes. Changes in phosphatase activity, protein stability, and intramolecular interactions appeared to be major drivers of clinical phenotype, with cancer-associated variants leading to the most drastic changes, while ASD and non-pathogenic variants associated with more mild and neutral changes, respectively. Importantly, we show via saturation mutagenesis that more than half of variants of unknown significance could be associated with disease phenotypes, while over half of Cowden syndrome mutations likely lead to cancer. These insights can assist in exploring potentially important clinical outcomes delineated by PTEN variation.
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Affiliation(s)
- Stephanie Portelli
- Structural Biology and Bioinformatics, Department of Biochemistry, University of Melbourne, Melbourne, Victoria, Australia
- Systems and Computational Biology, Bio21 Institute, University of Melbourne, Melbourne, Victoria, Australia
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Lucy Barr
- Structural Biology and Bioinformatics, Department of Biochemistry, University of Melbourne, Melbourne, Victoria, Australia
- Systems and Computational Biology, Bio21 Institute, University of Melbourne, Melbourne, Victoria, Australia
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Alex G.C. de Sá
- Structural Biology and Bioinformatics, Department of Biochemistry, University of Melbourne, Melbourne, Victoria, Australia
- Systems and Computational Biology, Bio21 Institute, University of Melbourne, Melbourne, Victoria, Australia
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Baker Department of Cardiometabolic Health, Melbourne Medical School, University of Melbourne, Melbourne, Victoria, Australia
| | - Douglas E.V. Pires
- Structural Biology and Bioinformatics, Department of Biochemistry, University of Melbourne, Melbourne, Victoria, Australia
- Systems and Computational Biology, Bio21 Institute, University of Melbourne, Melbourne, Victoria, Australia
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- School of Computing and Information Systems, University of Melbourne, Melbourne, Victoria, Australia
| | - David B. Ascher
- Structural Biology and Bioinformatics, Department of Biochemistry, University of Melbourne, Melbourne, Victoria, Australia
- Systems and Computational Biology, Bio21 Institute, University of Melbourne, Melbourne, Victoria, Australia
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Baker Department of Cardiometabolic Health, Melbourne Medical School, University of Melbourne, Melbourne, Victoria, Australia
- Department of Biochemistry, University of Cambridge, 80 Tennis Ct Rd, Cambridge CB2 1GA, United States
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14
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Molecular characterization of CNS paragangliomas identifies cauda equina paragangliomas as a distinct tumor entity. Acta Neuropathol 2020; 140:893-906. [PMID: 32926213 PMCID: PMC7666289 DOI: 10.1007/s00401-020-02218-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/26/2020] [Accepted: 08/27/2020] [Indexed: 12/17/2022]
Abstract
Paragangliomas/pheochromocytomas are rare neuroendocrine tumors that arise from the adrenal gland or ganglia at various sites throughout the body. They display a remarkable diversity of driver alterations and are associated with germline mutations in up to 40% of the cases. Comprehensive molecular profiling of abdomino-thoracic paragangliomas revealed four molecularly defined and clinically relevant subtypes. Paragangliomas of the cauda equina region are considered to belong to one of the defined molecular subtypes, but a systematic molecular analysis has not yet been performed. In this study, we analyzed genome-wide DNA methylation profiles of 57 cauda equina paragangliomas and show that these tumors are epigenetically distinct from non-spinal paragangliomas and other tumors. In contrast to paragangliomas of other sites, chromosomal imbalances are widely lacking in cauda equina paragangliomas. Furthermore, RNA and DNA exome sequencing revealed that frequent genetic alterations found in non-spinal paragangliomas—including the prognostically relevant SDH mutations—are absent in cauda equina paragangliomas. Histologically, cauda equina paragangliomas show frequently gangliocytic differentiation and strong immunoreactivity to pan-cytokeratin and cytokeratin 18, which is not common in paragangliomas of other sites. None of our cases had a familial paraganglioma syndrome. Tumors rarely recurred (9%) or presented with multiple lesions within the spinal compartment (7%), but did not metastasize outside the CNS. In summary, we show that cauda equina paragangliomas represent a distinct, sporadic tumor entity defined by a unique clinical and morpho-molecular profile.
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15
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Pires DEV, Rodrigues CHM, Ascher DB. mCSM-membrane: predicting the effects of mutations on transmembrane proteins. Nucleic Acids Res 2020; 48:W147-W153. [PMID: 32469063 PMCID: PMC7319563 DOI: 10.1093/nar/gkaa416] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/04/2020] [Accepted: 05/28/2020] [Indexed: 12/17/2022] Open
Abstract
Significant efforts have been invested into understanding and predicting the molecular consequences of mutations in protein coding regions, however nearly all approaches have been developed using globular, soluble proteins. These methods have been shown to poorly translate to studying the effects of mutations in membrane proteins. To fill this gap, here we report, mCSM-membrane, a user-friendly web server that can be used to analyse the impacts of mutations on membrane protein stability and the likelihood of them being disease associated. mCSM-membrane derives from our well-established mutation modelling approach that uses graph-based signatures to model protein geometry and physicochemical properties for supervised learning. Our stability predictor achieved correlations of up to 0.72 and 0.67 (on cross validation and blind tests, respectively), while our pathogenicity predictor achieved a Matthew's Correlation Coefficient (MCC) of up to 0.77 and 0.73, outperforming previously described methods in both predicting changes in stability and in identifying pathogenic variants. mCSM-membrane will be an invaluable and dedicated resource for investigating the effects of single-point mutations on membrane proteins through a freely available, user friendly web server at http://biosig.unimelb.edu.au/mcsm_membrane.
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Affiliation(s)
- Douglas E V Pires
- Computational Biology and Clinical Informatics, Baker Institute, Melbourne, Victoria 3004, Australia.,Structural Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Parkville, VIC, 3052, Australia.,School of Computing and Information Systems, University of Melbourne, Parkville, VIC, 3052, Australia
| | - Carlos H M Rodrigues
- Computational Biology and Clinical Informatics, Baker Institute, Melbourne, Victoria 3004, Australia.,Structural Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Parkville, VIC, 3052, Australia
| | - David B Ascher
- Computational Biology and Clinical Informatics, Baker Institute, Melbourne, Victoria 3004, Australia.,Structural Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Parkville, VIC, 3052, Australia.,Department of Biochemistry, University of Cambridge, Cambridge, CB2 1GA, UK
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16
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Main AM, Rossing M, Borgwardt L, Grønkær Toft B, Rasmussen ÅK, Feldt-Rasmussen U. Genotype-phenotype associations in PPGLs in 59 patients with variants in SDHX genes. Endocr Connect 2020; 9:793-803. [PMID: 32688340 PMCID: PMC7487185 DOI: 10.1530/ec-20-0279] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 07/19/2020] [Indexed: 12/31/2022]
Abstract
Phaeochromocytomas and paragangliomas (PPGLs) are tumours of the adrenal medulla and extra-adrenal sympathetic nervous system which often secrete catecholamines. Variants of the SDHX (SDHA, -AF2, -B, -C, -D) genes are a frequent cause of familial PPGLs. In this study from a single tertiary centre, we aimed to characterise the genotype-phenotype associations in patients diagnosed with germline variants in SDHX genes. We also assessed whether systematic screening of family members resulted in earlier detection of tumours. The study cohort comprised all individuals (n = 59) diagnosed with a rare variant in SDHX during a 13-year period. Patient- and pathology records were checked for clinical characteristics and histopathological findings. We found distinct differences in the clinical and histopathological characteristics between genetic variants in SDHB. We identified two SDHB variants with distinct phenotypical patterns. Family screening for SDHB variants resulted in earlier detection of tumours in two families. Patients with SDHA, SDHC and SDHD variants also had malignant phenotypes, underlining the necessity for a broad genetic screening of the proband. Our study corroborates previous findings of poor prognostic markers and found that the genetic variants and clinical phenotype are linked and, therefore, useful in the decision of clinical follow-up. Regular tumour screening of carriers of pathogenic variants may lead to an earlier diagnosis and expected better prognosis. The development of a combined algorithm with clinical, genetic, morphological, and biochemical factors may be the future for improved clinical risk stratification, forming a basis for larger multi-centre follow up studies.
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Affiliation(s)
- Ailsa Maria Main
- Department of Medical Endocrinology and Metabolism, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Correspondence should be addressed to A M Main or U Feldt-Rasmussen: or
| | - Maria Rossing
- Center for Genomic Medicine, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Line Borgwardt
- Center for Genomic Medicine, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Birgitte Grønkær Toft
- Department of Pathology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Åse Krogh Rasmussen
- Department of Medical Endocrinology and Metabolism, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Ulla Feldt-Rasmussen
- Department of Medical Endocrinology and Metabolism, Copenhagen University Hospital, Rigshospitalet, and Faculty of Health, Institute of Clinical and Scientific Research, Copenhagen, Denmark
- Correspondence should be addressed to A M Main or U Feldt-Rasmussen: or
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