Management of Abdominal Paraganglioma: A Single Center's Experience.

Background and Objectives: Paragangliomas (PGLs) are rare neuroendocrine extra-adrenal tumors that could be secreting mass. The symptoms are the typical triad of paroxysmal headache, hypertension and sweating, but could also be accompanied by symptoms involving multiple organs. Surgery is the gold standard treatment for both PGLs and pheochromocytomas (PHEOs). Material and Methods: We used a computerized endocrine surgery registry to record the demographic and clinical data of 153 patients who underwent surgery for PPGL between 2010 and 2023 at our hospital. Results: Thirteen patients (8.43%) with paragangliomas underwent surgery at our institute. Five patients presented symptomatic syndrome. Preoperative investigations included enhanced abdominal CT (nine patients) and enhanced MRI (seven patients). In cases of suspicious mass, we performed 131I-MIBG scans (two patients) or 68GA-DOTATOC PET-CT scans (11 patients). Laparoscopic approach was used in four cases (30.7%) and abdominal laparotomy in the other nine (69.3%). Biochemical tests were performed on all patients. Conclusions: In this retrospective study, we discuss the multidisciplinary management in our institute of this rare disease, from its challenging diagnosis to the surgical strategy for PGLs. Laparoscopic surgery is the gold standard, but a tailored approach should be adopted for each patient.

Regulation of epinephrine biosynthesis in HRAS-mutant paragangliomas.

The biochemical phenotype of paragangliomas (PGLs) is highly dependent on the underlying genetic background and tumor location. PGLs at extra-adrenal locations usually do not express phenylethanolamine N-methyltransferase (PNMT), the enzyme required for epinephrine production, which was explained by the absence of glucocorticoids. PGLs with pathogenic variants (PVs) in Harvey rat sarcoma viral oncogene homolog (HRAS) can occur in or outside of the adrenal, but always synthesize epinephrine independently of the localization. Here, we characterize the signaling pathways through which PVs in HRAS influence PNMT expression. Catecholamines, cortisol, and transcriptional features of PGL tissues with known genetic background were analyzed. Genetically modified rat pheochromocytoma cells carrying PVs in Hras were generated and analyzed for regulation of Pnmt expression. Elevated epinephrine contents in PGLs with PVs in HRAS were accompanied by enrichment in mitogen-activated protein kinase (MAPK) signaling compared to PGLs with PVs in genes that activate hypoxia pathways. In vitro, Hras PVs increased Pnmt expression and epinephrine biosynthesis through increased phosphorylation of stimulatory protein 1 via MAPK signaling. Here, we provide a molecular mechanism that explains the PV-dependent epinephrine production of PGLs.

A Multicenter Epidemiological Study on Second Malignancy in Non-Syndromic Pheochromocytoma/Paraganglioma Patients in Italy.

No studies have carried out an extensive analysis of the possible association between non-syndromic pheochromocytomas and paragangliomas (PPGLs) and other malignancies. To assess >the risk of additional malignancy in PPGL, we retrospectively evaluated 741 patients with PPGLs followed-up in twelve referral centers in Italy. Incidence of second malignant tumors was compared between this cohort and Italian patients with two subsequent malignancies. Among our patients, 95 (12.8%) developed a second malignant tumor, which were mainly prostate, colorectal and lung/bronchial cancers in males, breast cancer, differentiated thyroid cancer and melanoma in females. The standardized incidence ratio was 9.59 (95% CI 5.46-15.71) in males and 13.21 (95% CI 7.52-21.63) in females. At multivariable analysis, the risk of developing a second malignant tumor increased with age at diagnosis (HR 2.50, 95% CI 1.15-5.44, p = 0.021 for 50-59 vs. <50-year category; HR 3.46, 95% CI 1.67-7.15, p < 0.001 for >60- vs. <50-year). In patients with available genetic evaluation, a positive genetic test was inversely associated with the risk of developing a second tumor (HR 0.25, 95% CI 0.10-0.63, p = 0.003). In conclusion, PPGLs patients have higher incidence of additional malignant tumors compared to the general population who had a first malignancy, which could have an impact on the surveillance strategy.

Improving Outcomes in Carotid Body Tumors Treatment: The Impact of a Multidisciplinary Team Approach.

BACKGROUND: The purpose of this study was to evaluate how a multidisciplinary approach, including patients and familiar genetic counseling, preoperative succinate-dehydrogenase (SDH) gene mutation analysis, preoperative adjunctive endovascular procedures (PAEPs) and postoperative rehabilitative team may affect the outcomes in patients who underwent surgery for carotid body tumors (CBTs). METHODS: Fifty-seven consecutive CBT resections were performed from January 1995 to December 2019 in a single center institution. Two groups of patients were compared: group A (1995-2003; n = 10) and group B (2004-2019; n = 47), treated before and after the establishment of a multidisciplinary approach to CBTs. Group A and group B were evaluated retrospectively and prospectively for SDH mutations, respectively. PAEPs (external carotid artery stenting, percutaneous transfemoral embolization or direct percutaneous puncture of the tumor with simultaneous embolization) were performed only in patients of group B, when the size of the tumor exceeded the 45 mm. Primary endpoints were blood loss (BL) and cranial nerve injuries. Secondary endpoint was the number of new silent masses (NSMs) discovered after genetic evaluation. RESULTS: SDH mutations were found in 2 patients of group A and in 11 patients of group B. There were no significant differences in mass diameter between the groups. A significant difference regarding the surgical procedure time was observed in the 2 groups, with a higher time in the group A (Group A: 180 ± 77.3; Group B: 138 ± 54.5, P= 0.04). BL was significantly lower in group B (203 ± 69.5 mL vs. 356 ± 102 mL; P = 0.0001), as well as for patients underwent PAEPs vs. those underwent direct surgery (n = 15, 149 ± 53 mL vs. n = 42, 273 ± 88 mL; P = 0.0001). No differences between transient and persistent cranial nerve injuries were observed between the 2 groups. Carotid reconstruction was necessary for 2 patients of group A (n = 2 vs. n = 0; P = 0.02). Unilateral tumor recurrence was detected in 7 patients, with a significantly higher rate (P ≤ 0.002) in patients carrying SDH mutations compared to those without SDH mutation (wild-type). SDH mutations detected in the groups lead to discover 7 NSMs (group A n = 1 vs. group B n = 6; P = 1.00). CONCLUSION: The impact of the multidisciplinary team suggests that surgical resection still remains the gold standard for the treatment of CBTs, but the use of PAEPs in selected cases may reduce surgical procedure time, BL and the need for reconstructive carotid surgery. Genetic counseling and SDH gene analysis allow to diagnose NSMs in asymptomatic patients. Larger studies should be considered to evaluate the effectiveness of postoperative rehabilitative program.

Pheochromocytomas and paragangliomas in children: Data from the Italian Cooperative Study (TREP).

BACKGROUND: Pheochromocytomas (PCs) are neuroendocrine tumors arising from the chromaffin cells of the adrenal gland, and paragangliomas (PGLs) are their extra-adrenal counterparts arising from ganglia along the sympathetic/parasympathetic chain. Surgery is the cornerstone of treatment. A sporatic or inherited germline mutation is commonly associated. MATERIALS AND METHODS: Among over 1000 patients registered into the Tumori Rari in Età Pediatrica-rare tumors in pediatric age project-from 2000 to 2019, 50 were affected by PC/PGL. All clinical and therapeutic data were evaluated. RESULTS: Twenty-eight patients had PC and 22 had PGL. Age at diagnosis ranged between 5 and 17 years. Thirty-five patients had symptoms related to catecholamine hypersecretion; in 7 of 50 patients, diagnosis was incidental or done during assessment of a familial syndrome. In all cases, conventional imaging was effective to assess the presence of a tumor. In addition, 18 of 38 functional imaging studies were positive (61%). Forty-eight patients were eligible for surgery: a complete resection was more frequently achieved in PC than in PGL (26/28 vs 11/22). All relapses were treated with surgery alone, surgery plus medical treatment, or chemotherapy alone; one PC with metastasis at diagnosis received radiotherapy only. Forty-four patients were in the first, second, or third complete remission (10/50 recurred; 8/10 carried a germline mutation). Five of 50 patients were alive with disease. One patient died of disease. CONCLUSIONS: Surgery can be curative in most tumors but it may not be always effective in removing PGLs. Severe postsurgical sequelae may affect these patients. Genetic tests should always be considered in individuals affected, and genetic counseling should be offered to their families.

A moonshot approach toward the management of cancer patients in the COVID-19 time: what have we learned and what could the Italian network of cancer centers (Alliance Against Cancer, ACC) do after the pandemic wave?

If we focus our attention on seven main features of COVID-19 infection (heterogeneity, fragility, lack of effective treatments and vaccines, "miraculous cures", psychological suffering, deprivation, and globalization), we may establish parallelism with the challenges faced in the steep road to the understanding and treatment of neoplastic diseases. How the similarities between these two conditions can help us cope with the emergency effort represented by the management of cancer patients in the COVID-19 era, today and in the future? In a manner similar to the Cancer Moonshot initiative in the United States, we can hypothesize a multinational moonshot project towards the management of cancer patients during COVID-19 pandemic. In particular, we believe that the main road to elaborate meaningful scientific evidence is represented by the collection of all the data on COVID-19 and cancer comorbidity that are and will become available in cancer centers, coupled with the design of large clinical studies. To address this goal, it is essential to identify the entity that can produce this scientific evidences and the potentially most successful research strategy to undertake. The largest Italian organization for cancer research, Alliance Against Cancer (Alleanza Contro il Cancro, ACC), is called to play a scientific leadership in addressing these challenges, which requires the coordination of oncology teams at regional, national, and international levels. To fulfill this commitment, ACC will create a liaison with health government agencies in order to develop "dynamic" indications able to fight such an unpredictable pandemic.

COVID-19: ensuring our medical equipment can meet the challenge.

To predict the spread of coronavirus disease globally and consequently prepare the hospital facilities with the required technology is a challenge. The availability of essential medical equipment to support patients affected by Covid-19 is globally limited. Areas covered This perspective gives a technical view of the pandemic focusing on the main actions taken by regulatory agencies to cope with the shortage of devices. The risk/benefit assessment and the main infection control policies in the clinical practices are also looked at. Expert opinion Regulatory agencies have amended their medical devices directives to address the pandemic, but each in a different way. In this exceptional situation scientist and technology experts in collaboration with medical specialists should work together to re-assess the risk analysis on medical equipment management and their use and re-use in this context with the aim to improve global health care Every effort must be made to provide the necessary devices at least with the minimum acceptable performances for Covid-19 patients while maintaining a high standard of safety for users. The aim of the present manuscript is to highlight the technical challenges in order to prevent, through targeted actions, operating standards from falling below the standards of care due to a lack of medical devices. Abbreviations AKI: acute Kidney Injury; ARGMD: Australian Regulatory Guidelines for Medical Devices; Covid-19: Coronavirus disease; FDA: Food and Drug Administration; ECMO: Extracorporeal Membrane Oxygenation; EU: European Union; ICU: Intensive Care Unit; WHO: World Health Organization; MHRA: Medicines and Healthcare products Regulatory Agency; MDR: Medical Device Regulation; SARI: Severe Acute Respiratory Infection.

E2F1 germline copy number variations and melanoma susceptibility.

BACKGROUND: Melanoma is an aggressive type of skin cancer whose aetiology remains elusive as both environmental and genetic factors can contribute to its development. Recent studies have demonstrated the existence of multiple copies of E2F1 gene in melanoma specimens which could explain the deregulated E2F1 activity in this type of cancer. This finding suggests a key role for this transcription factor in the malignant transformation of melanocytes. Therefore, E2F1 has been considered as a potential therapeutic target for this form of skin cancer. Since germline copy number variations (CNVs) have been associated with increased susceptibility to different types of cancer, the aim of our study was to assess germline E2F1 CNV in melanoma patients. However, CNVs not necessarily lead to gene dosage imbalance, hence, further factors, in association with CNVs, could contribute to clinical manifestations. Considering that heat stress has been hypothesised as a contributing factor to skin cancer, we also investigated the effect of heat stress on E2F1 expression. METHODS: E2F1 CNV was measured in genomic DNA isolated from blood of 552 patients diagnosed with melanoma and 520 healthy subjects using TaqMan Copy Number Assays. E2F1 mRNA expression was also evaluated by RT-qPCR in the melanoma cell line, SK MEL 267, before and after exposure to heat stress. RESULTS: We found that patients diagnosed with melanoma (1.6%, 9/552) harboured frequently altered germline E2F1 copies compared to healthy subjects (0%, 0/520). Moreover, the difference among the two groups was statistically significant (p = 0.004). Furthermore, we found that heat exposure alone can significantly induce E2F1 expression. CONCLUSIONS: This is the first study that shows a relation between germline E2F1 CNV and melanoma, suggesting that altered copies of this gene might be a predisposing factor to skin cancer. Our results also suggest that environmental insults, such as heat stress, could contribute to an aberrant E2F1 activity by inducing E2F1 mRNA expression. Therefore, subjects with multiple constitutive copies of E2F1 are at greater risk of developing melanoma when exposed to heat. Altogether our results corroborate with the hypothesis that susceptibility to melanoma depends on both the environment and genetic factors.

Correction to: Multiple endocrine neoplasia type 1: analysis of germline MEN1 mutations in the Italian multicenter MEN1 patient database.

The original version of this article unfortunately contained a mistake in Table 2. The table 2 was truncated in the original publication. The full table 2 is given below.

Gain-of-function mutations in DNMT3A in patients with paraganglioma.

PURPOSE: The high percentage of patients carrying germline mutations makes pheochromocytomas/paragangliomas the most heritable of all tumors. However, there are still cases unexplained by mutations in the known genes. We aimed to identify the genetic cause of disease in patients strongly suspected of having hereditary tumors. METHODS: Whole-exome sequencing was applied to the germlines of a parent-proband trio. Genome-wide methylome analysis, RNA-seq, CRISPR/Cas9 gene editing, and targeted sequencing were also performed. RESULTS: We identified a novel de novo germline mutation in DNMT3A, affecting a highly conserved residue located close to the aromatic cage that binds to trimethylated histone H3. DNMT3A-mutated tumors exhibited significant hypermethylation of homeobox-containing genes, suggesting an activating role of the mutation. CRISPR/Cas9-mediated knock-in in HeLa cells led to global changes in methylation, providing evidence of the DNMT3A-altered function. Targeted sequencing revealed subclonal somatic mutations in six additional paragangliomas. Finally, a second germline DNMT3A mutation, also causing global tumor DNA hypermethylation, was found in a patient with a family history of pheochromocytoma. CONCLUSION: Our findings suggest that DNMT3A may be a susceptibility gene for paragangliomas and, if confirmed in future studies, would represent the first example of gain-of-function mutations affecting a DNA methyltransferase gene involved in cancer predisposition.

65 YEARS OF THE DOUBLE HELIX: Genetics informs precision practice in the diagnosis and management of pheochromocytoma.

Although the authors of the present review have contributed to genetic discoveries in the field of pheochromocytoma research, we can legitimately ask whether these advances have led to improvements in the diagnosis and management of patients with pheochromocytoma. The answer to this question is an emphatic Yes! In the field of molecular genetics, the well-established axiom that familial (genetic) pheochromocytoma represents 10% of all cases has been overturned, with >35% of cases now attributable to germline disease-causing mutations. Furthermore, genetic pheochromocytoma can now be grouped into five different clinical presentation types in the context of the ten known susceptibility genes for pheochromocytoma-associated syndromes. We now have the tools to diagnose patients with genetic pheochromocytoma, identify germline mutation carriers and to offer gene-informed medical management including enhanced surveillance and prevention. Clinically, we now treat an entire family of tumors of the paraganglia, with the exact phenotype varying by specific gene. In terms of detection and classification, simultaneous advances in biochemical detection and imaging localization have taken place, and the histopathology of the paraganglioma tumor family has been revised by immunohistochemical-genetic classification by gene-specific antibody immunohistochemistry. Treatment options have also been substantially enriched by the application of minimally invasive and adrenal-sparing surgery. Finally and most importantly, it is now widely recognized that patients with genetic pheochromocytoma/paraganglioma syndromes should be treated in specialized centers dedicated to the diagnosis, treatment and surveillance of this rare neoplasm.

Multiple endocrine neoplasia type 1: analysis of germline MEN1 mutations in the Italian multicenter MEN1 patient database.

PURPOSE: Multiple endocrine neoplasia type 1 (MEN1) is caused by germline inactivating mutations of the MEN1 gene. Currently, no direct genotype-phenotype correlation is identified. We aim to analyze MEN1 mutation site and features, and possible correlations between the mutation type and/or the affected menin functional domain and clinical presentation in patients from the Italian multicenter MEN1 database, one of the largest worldwide MEN1 mutation series published to date. METHODS: The study included the analysis of MEN1 mutation profile in 410 MEN1 patients [370 familial cases from 123 different pedigrees (48 still asymptomatic at the time of this study) and 40 single cases]. RESULTS: We identified 99 different mutations: 41 frameshift [small intra-exon deletions (28) or insertions (13)], 13 nonsense, 26 missense and 11 splicing site mutations, 4 in-frame small deletions, and 4 intragenic large deletions spanning more than one exon. One family had two different inactivating MEN1 mutations on the same allele. Gastro-entero-pancreatic tumors resulted more frequent in patients with a nonsense mutation, and thoracic neuroendocrine tumors in individuals bearing a splicing-site mutation. CONCLUSIONS: Our data regarding mutation type frequency and distribution are in accordance with previously published data: MEN1 mutations are scattered through the entire coding region, and truncating mutations are the most common in MEN1 syndrome. A specific direct correlation between MEN1 genotype and clinical phenotype was not found in all our families, and wide intra-familial clinical variability and variable disease penetrance were both confirmed, suggesting a role for modifying, still undetermined, factors, explaining the variable MEN1 tumorigenesis.

Correction to: Paragangliomas arise through an autonomous vasculo-angio-neurogenic program inhibited by imatinib.

The given and family names of two co-authors were incorrect in the published article. The correct spelling should read as: Sampath Chandra Prasad and Vinagolu K Rajasekhar.

Paragangliomas arise through an autonomous vasculo-angio-neurogenic program inhibited by imatinib.

Tumours can be viewed as aberrant tissues or organs sustained by tumorigenic stem-like cells that engage into dysregulated histo/organogenetic processes. Paragangliomas, prototypical organoid tumours constituted by dysmorphic variants of the vascular and neural tissues found in normal paraganglia, provide a model to test this hypothesis. To understand the origin of paragangliomas, we built a biobank comprising 77 cases, 18 primary cultures, 4 derived cell lines, 80 patient-derived xenografts and 11 cell-derived xenografts. We comparatively investigated these unique complementary materials using morphofunctional, ultrastructural and flow cytometric assays accompanied by microRNA studies. We found that paragangliomas contain stem-like cells with hybrid mesenchymal/vasculoneural phenotype, stabilized and expanded in the derived cultures. The viability and growth of such cultures depended on the downregulation of the miR-200 and miR-34 families, which allowed high PDGFRA and ZEB1 protein expression levels. Both tumour tissue- and cell culture-derived xenografts recapitulated the vasculoneural paraganglioma structure and arose from mesenchymal-like cells through a fixed developmental sequence. First, vasculoangiogenesis organized the microenvironment, building a perivascular niche which in turn supported neurogenesis. Neuroepithelial differentiation was associated with severe mitochondrial dysfunction, not present in cultured paraganglioma cells, but acquired in vivo during xenograft formation. Vasculogenesis was the Achilles' heel of xenograft development. In fact, imatinib, that targets endothelial-mural signalling, blocked paraganglioma xenograft formation (11 xenografts from 12 cell transplants in the control group versus 2 out of 10 in the treated group, P = 0.0015). Overall our key results were unaffected by the SDHx gene carrier status of the patient, characterized for 70 out of 77 cases. In conclusion, we explain the biphasic vasculoneural structure of paragangliomas and identify an early and pharmacologically actionable phase of paraganglioma organization.

Temozolomide treatment of a malignant pheochromocytoma and an unresectable MAX-related paraganglioma.

Pheochromocytomas (PCCs) and paragangliomas (PGLs) are neuroendocrine tumors with a strong genetic background. The mainstay of treatment for PCC/PGLs is surgery. However, for unresectable lesions, no curative treatment is currently available. Temozolomide (TMZ) has been shown to determine radiological and biochemical response in malignant PCC/PGLs. We report two cases of PCC/PGLs treated with TMZ. Case 1 is a 51-year-old man with local and distant recurrence (liver and bone metastases) of right adrenal PCC. Case 2 is a 54-year-old woman with a PCC/PGL syndrome caused by a mutation in MAX gene (c.171+1G>A), operated on for bilateral adrenal PCC and presenting with a large unresectable abdominal PGL. Both patients presented hypertension due to catecholamine hypersecretion. TMZ determined radiological response according to RECIST criteria, reduction of urinary catecholamine levels, and controlled hypertension in both patients. Furthermore, the current study demonstrates, for the first time, that MAX-related PGLs are responsive to TMZ.

PheoSeq: A Targeted Next-Generation Sequencing Assay for Pheochromocytoma and Paraganglioma Diagnostics.

Genetic diagnosis is recommended for all pheochromocytoma and paraganglioma (PPGL) cases, as driver mutations are identified in approximately 80% of the cases. As the list of related genes expands, genetic diagnosis becomes more time-consuming, and targeted next-generation sequencing (NGS) has emerged as a cost-effective tool. This study aimed to optimize targeted NGS in PPGL genetic diagnostics. A workflow based on two customized targeted NGS assays was validated to study the 18 main PPGL genes in germline and frozen tumor DNA, with one of them specifically directed toward formalin-fixed paraffin-embedded tissue. The series involved 453 unrelated PPGL patients, of whom 30 had known mutations and were used as controls. Partial screening using Sanger had been performed in 275 patients. NGS results were complemented with the study of gross deletions. NGS assay showed a sensitivity ≥99.4%, regardless of DNA source. We identified 45 variants of unknown significance and 89 pathogenic mutations, the latter being germline in 29 (7.2%) and somatic in 58 (31.7%) of the 183 tumors studied. In 37 patients previously studied by Sanger sequencing, the causal mutation could be identified. We demonstrated that both assays are an efficient and accurate alternative to conventional sequencing. Their application facilitates the study of minor PPGL genes, and enables genetic diagnoses in patients with incongruent or missing clinical data, who would otherwise be missed.

Clinical Characterization of the Pheochromocytoma and Paraganglioma Susceptibility Genes SDHA, TMEM127, MAX, and SDHAF2 for Gene-Informed Prevention.

IMPORTANCE: Effective cancer prevention is based on accurate molecular diagnosis and results of genetic family screening, genotype-informed risk assessment, and tailored strategies for early diagnosis. The expanding etiology for hereditary pheochromocytomas and paragangliomas has recently included SDHA, TMEM127, MAX, and SDHAF2 as susceptibility genes. Clinical management guidelines for patients with germline mutations in these 4 newly included genes are lacking. OBJECTIVE: To study the clinical spectra and age-related penetrance of individuals with mutations in the SDHA, TMEM127, MAX, and SDHAF2 genes. DESIGN, SETTING, AND PATIENTS: This study analyzed the prospective, longitudinally followed up European-American-Asian Pheochromocytoma-Paraganglioma Registry for prevalence of SDHA, TMEM127, MAX, and SDHAF2 germline mutation carriers from 1993 to 2016. Genetic predictive testing and clinical investigation by imaging from neck to pelvis was offered to mutation-positive registrants and their relatives to clinically characterize the pheochromocytoma/paraganglioma diseases associated with mutations of the 4 new genes. MAIN OUTCOMES AND MEASURES: Prevalence and spectra of germline mutations in the SDHA, TMEM127, MAX, and SDHAF2 genes were assessed. The clinical features of SDHA, TMEM127, MAX, and SDHAF2 disease were characterized. RESULTS: Of 972 unrelated registrants without mutations in the classic pheochromocytoma- and paraganglioma-associated genes (632 female [65.0%] and 340 male [35.0%]; age range, 8-80; mean [SD] age, 41.0 [13.3] years), 58 (6.0%) carried germline mutations of interest, including 29 SDHA, 20 TMEM127, 8 MAX, and 1 SDHAF2. Fifty-three of 58 patients (91%) had familial, multiple, extra-adrenal, and/or malignant tumors and/or were younger than 40 years. Newly uncovered are 7 of 63 (11%) malignant pheochromocytomas and paragangliomas in SDHA and TMEM127 disease. SDHA disease occurred as early as 8 years of age. Extra-adrenal tumors occurred in 28 mutation carriers (48%) and in 23 of 29 SDHA mutation carriers (79%), particularly with head and neck paraganglioma. MAX disease occurred almost exclusively in the adrenal glands with frequently bilateral tumors. Penetrance in the largest subset, SDHA carriers, was 39% at 40 years of age and is statistically different in index patients (45%) vs mutation-carrying relatives (13%; P < .001). CONCLUSIONS AND RELEVANCE: The SDHA, TMEM127, MAX, and SDHAF2 genes may contribute to hereditary pheochromocytoma and paraganglioma. Genetic testing is recommended in patients at clinically high risk if the classic genes are mutation negative. Gene-specific prevention and/or early detection requires regular, systematic whole-body investigation.

Impaired Release of Vitamin D in Dysfunctional Adipose Tissue: New Cues on Vitamin D Supplementation in Obesity.

Context: Vitamin D accumulates in adipose tissue (AT), and vitamin D deficiency is frequent in obesity. Objective: We hypothesize that trafficking of vitamin D is altered in dysfunctional AT. Design, Patients, Settings: Fifty-four normal-weight and 67 obese males were recruited in a prospective study and randomly assigned to supplementation with 50 µg/wk 25-hydroxyvitamin-D3 or 150 µg/wk vitamin D3 for 1 year, raising dosage by 50% if vitamin D sufficiency [serum 25-hydroxyvitamin-D3 >50 nmol/L], was not achieved at 6 months; 97 subjects completed the study. Methods: Vitamin D3 and 25-hydroxyvitamin-D3 were quantified by HPLC-MS in control and insulin-resistant (IR) 3T3-L1 cells and subcutaneous AT (SAT) from lean and obese subjects, incubated with or without adrenaline; expression of 25-hydroxylase (Cyp27a1), 1α-hydroxylase (Cyp27b1), and vitamin D receptor (Vdr) was analyzed by real-time polymerase chain reaction. Results: In IR adipocytes, uptake of D3 and 25-hydroxyvitamin-D3 was higher, but, after adrenaline stimulation, the decrement in D3 and 25-hydroxyvitamin-D3 was stronger in control cells, which also showed increased expression of Cyp27a1 and Cyp27b1 and higher levels of 25-hydroxyvitamin-D3. In SAT from obese subjects, adrenaline-induced release of D3 and 25-hydroxyvitamin-D3 was blunted; in both IR cells and obese SAT, protein expression of ß2-adrenergic receptor was reduced. Supplementation with 25-hydroxyvitamin-D3 was more effective in achieving vitamin D sufficiency in obese, but not in normal weight subjects. Conclusion: Dysfunctional AT shows a reduced catecholamine-induced release of D3 and 25-hydroxyvitamin-D3 and altered activity of vitamin D-metabolizing enzymes; for these reasons supplementation with 25-hydroxyvitamin-D3 is more effective in obese individuals.