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Open access

Debra M Gordon, Pablo Beckers, Emily Castermans, Sebastian Jcmm Neggers, Liliya Rostomyan, Vincent Bours, Patrick Petrossians, Vinciane Dideberg, Albert Beckers, and Adrian F. Daly

Objective: Screening studies have established genetic risk profiles for diseases such as multiple endocrine neoplasia type 1 (MEN1) and pheochromocytoma-paraganglioma (PPGL). Founder effects play an important role in regional/national epidemiology of endocrine cancers, particularly PPGL. Founder effects in the Netherlands have been described for various diseases, some of which established themselves in South Africa due to Dutch emigration. The role of Dutch founder effects in South Africa have not been explored in PPGL.

Design: We performed a single-center study in South Africa of the germline genetic causes of isolated/syndromic neuroendocrine tumors.

Methods: Next-generation panel and multiplex ligand-dependent probe amplification for endocrine neoplasia risk genes.

Results: From a group of 13 patients we identified six with PPGL, four with sporadic or familial isolated pituitary adenomas (FIPA), and three with clinical MEN1; genetic variants were identified in 9/13 cases. We identified the Dutch founder exon 3 deletion in SDHB in two apparently-unrelated individuals with distinct ethnic backgrounds that had metastatic PPGL. Asymptomatic carriers with this Dutch founder SDHB exon 3 deletion were also identified. Other PPGL patients had variants in SDHB, SDHD and three MEN1 variants were identified among MEN1 and young-onset pituitary adenoma patients.

Conclusions: This is the first identification of a Dutch founder effect for PPGL in South Africa. Awareness of the presence of this exon 3 SDHB deletion could promote targeted screening at a local level. Insights into PPGL genetics in South Africa could be achieved by studying existing patient databases for Dutch founder mutations in SDHx genes.

Open access

Jan Kvasnička, Ondřej Petrák, Tomáš Zelinka, Judita Klímová, Barbora Kološová, Květoslav Novák, David Michalský, Jiří Widimský Jr, and Robert Holaj

Background

Pheochromocytomas (PHEO) are tumours with the ability to produce, metabolize and secrete catecholamines. Catecholamines overproduction leads to the decrease of longitudinal function of the left ventricle (LV) measured by speckle-tracking echocardiography. Patients with PHEO have a lower magnitude of global longitudinal strain (GLS) than patients with essential hypertension. GLS normalization is expected after resolution of catecholamine overproduction.

Methods

Twenty-four patients (14 females and 10 males) with a recent diagnosis of PHEO have been examined before and 1 year after adrenalectomy. An echocardiographic examination including speckle-tracking analysis with the evaluation of GLS and regional longitudinal strain (LS) in defined groups of LV segments (basal, mid-ventricular and apical) was performed.

Results

One year after adrenalectomy, the magnitude of GLS increased (−14.3 ± 1.8 to −17.7 ± 1.6%; P < 0.001). When evaluating the regional LS, the most significant increase in the differences was evident in the apical segment compared to mid-ventricular and basal segments of LV (−5.4 ± 5.0 vs −1.9 ± 2.7 vs −1.6 ± 3.8; P < 0.01).

Conclusions

In patients with PHEO, adrenalectomy leads to an improvement of subclinical LV dysfunction represented by the increasing magnitude of GLS, which is the most noticeable in apical segments of LV.

Open access

Sarah Zaheer, Kayla Meyer, Rebecca Easly, Omar Bayomy, Janet Leung, Andrew W Koefoed, Mahyar Heydarpour, Roy Freeman, and Gail K Adler

Glucocorticoid use is the most common cause of secondary osteoporosis. Poor skeletal health related to glucocorticoid use is thought to involve inhibition of the Wnt/β-catenin signaling pathway, a key pathway in osteoblastogenesis. Sclerostin, a peptide produced primarily by osteocytes, is an antagonist of the Wnt/β-catenin signaling pathway, raising the possibility that sclerostin is involved in glucocorticoids’ adverse effects on bone. The aim of this study was to determine whether an acute infusion of cosyntropin (i.e. ACTH(1–24)), which increases endogenous cortisol, increases serum sclerostin levels as compared to a placebo infusion. This study was performed using blood samples obtained from a previously published, double-blind, placebo-controlled, randomized, cross-over study among healthy men and women who received infusions of placebo or cosyntropin after being supine and fasted overnight (ClinicalTrials.gov NCT02339506). A total of 17 participants were analyzed. There was a strong correlation (R2 = 0.65, P < 0.0001) between the two baseline sclerostin measurements measured at the start of each visit, and men had a significantly higher average baseline sclerostin compared to women. As anticipated, cosyntropin significantly increased serum cortisol levels, whereas cortisol levels fell during placebo infusion, consistent with the diurnal variation in cortisol. There was no significant effect of cosyntropin as compared to placebo infusions on serum sclerostin over 6–24 h (P = 0.10). In conclusion, this randomized, placebo-controlled study was unable to detect a significant effect of a cosyntropin infusion on serum sclerostin levels in healthy men and women.

Open access

Sneha Arya, Sandeep Kumar, Anurag R Lila, Vijaya Sarathi, Saba Samad Memon, Rohit Barnabas, Hemangini Thakkar, Virendra A Patil, Nalini S Shah, and Tushar R Bandgar

Objective

The literature regarding gonadoblastoma risk in exonic Wilms’ tumor suppressor gene (WT1) pathogenic variants is sparse. The aim of this study is to describe the phenotypic and genotypic characteristics of Asian–Indian patients with WT1 pathogenic variants and systematically review the literature on association of exonic WT1 pathogenic variants and gonadoblastoma.

Design

Combined retrospective–prospective analysis.

Methods

In this study, 46,XY DSD patients with WT1 pathogenic variants detected by clinical exome sequencing from a cohort of 150 index patients and their affected relatives were included. The PubMed database was searched for the literature on gonadoblastoma with exonic WT1 pathogenic variants.

Results

The prevalence of WT1 pathogenic variants among 46,XY DSD index patients was 2.7% (4/150). All the four patients had atypical genitalia and cryptorchidism. None of them had Wilms’ tumor till the last follow-up, whereas one patient had late-onset nephropathy. 11p13 deletion was present in one patient with aniridia. The family with p.Arg458Gln pathogenic variant had varied phenotypic spectrum of Frasier syndrome; two siblings had gonadoblastoma, one of them had growing teratoma syndrome (first to report with WT1). On literature review, of >100 exonic point pathogenic variants, only eight variants (p.Arg462Trp, p.Tyr177*, p.Arg434His, p.Met410Arg, p.Gln142*, p.Glu437Lys, p.Arg458*, and p.Arg458Gln) in WT1 were associated with gonadoblastoma in a total of 15 cases (including our two cases).

Conclusions

WT1 alterations account for 3% of 46,XY DSD patients in our cohort. 46,XY DSD patients harboring exonic WT1 pathogenic variants carry a small but definitive risk of gonadoblastoma; hence, these patients require a gonadoblastoma surveillance with a more stringent surveillance in those harboring a gonadoblastoma-associated variant.

Open access

Lanping Jiang, Xiaoyan Peng, Bingbin Zhao, Lei Zhang, Lubin Xu, Xuemei Li, Min Nie, and Limeng Chen

Purposes: This study was conducted to identify the frequent mutations from reported Chinese Gitelman syndrome (GS) patients, to predict three-dimensional structure change of human Na-Cl co-transporter (hNCC), and to test the activity of these mutations and some novel mutations in vitro and in vivo.

Methods: SLC12A3 gene mutations in Chinese GS patients previously reported in the PubMed, CNKI and Wanfang database were summarized. Predicted configurations of wild type (WT) and mutant proteins were achieved using the I-TASSER workplace. Six missense mutations (T60M, L215F, D486N, N534K, Q617R and R928C) were generated by site-directed mutagenesis. 22Na+ uptake experiment was carried out in the Xenopus laevis oocyte expression system. 35 GS patients and 20 healthy volunteers underwent the thiazide test.

Results: T60M, T163M,D486N, R913Q, R928C and R959 frameshift were frequent SLC12A3 gene mutations (mutated frequency >3%) in 310 Chinese GS families. The protein’s three-dimensional structure was predicted to be altered in all mutations. Compared with WT hNCC, the thiazide-sensitive 22Na+ uptake was significantly diminished for all 6 mutations: T60M 22±9.2%, R928C 29±12%, L215F 38±14%, N534K 41±15.5%, Q617R 63±22.1% and D486N 77±20.4%. In thiazide test, the net increase in chloride fractional excretion in 20 healthy controls was significantly higher than GS patients with or without T60M or D486N mutations.

Conclusions: Frequent mutations (T60M, D486N, R928C) and novel mutations (L215F, N534K and Q617R) lead to protein structure alternation and protein dysfunction verified by 22Na+ uptake experiment in vitro and thiazide test on patients.

Open access

Luis Eduardo Barbalho de Mello, Thaise Nayane Ribeiro Carneiro, Aline Neves Araujo, Camila Xavier Alves, Pedro Alexandre Favoretto Galante, Vanessa Candiotti Buzatto, Maria das Graças de Almeida, Karina Marques Vermeulen-Serpa, Sancha H. de Lima Vale, Fernando José de Pinto Paiva, José Brandão-Neto, and Janete Maria Cerutti

The genetics underlying non-syndromic familial non-medullary thyroid carcinoma (FNMTC) is still poorly understood. To identify susceptibility genes for FNMTC, we performed whole exome sequencing (WES) in a Brazilian family affected by papillary thyroid carcinoma (PTC) in three consecutive generations. WES was performed in four affected and two unaffected family members. Manual inspection in over 100 previously reported susceptibility genes for FNMTC showed that no variants in known genes co-segregated with disease phenotype in this family. Novel candidate genes were investigated using PhenoDB and filtered using Genome Aggregation (gnomAD) and Online Archive of Brazilian Mutations (ABraOM) population databases. The missense variant p.Ile657Met in the NID1 gene was the only variant that co-segregated with the disease, while absent in unaffected family members and controls. The allele frequency for this variant was <0.0001 in the gnomAD and ABbraOM databases. In silico analysis predicted the variant to be deleterious or likely damaging to the protein function. Somatic mutations in NID1 gene were found in nearly 500 cases of different cancer subtypes in the intOGen platform. Immunohistochemistry analysis showed NID1 expression in PTC cells, while it was absent in normal thyroid tissue. Our findings were corroborated using data from the TCGA cohort. Moreover, higher expression of NID1 was associated with higher likelihood of relapse after treatment and N1b disease in PTCs from the TCGA cohort. Although replication studies are needed to better understand the role of this variant in the FNMTC susceptibility, the NID1 variant (c.1971T>G) identified in this study fulfills several criteria that suggest it as a new FNMTC predisposing gene.

Open access

Yuerong Yan, Lili You, Xiaoyi Wang, Zhuo Zhang, Feng Li, Hongshi Wu, Muchao Wu, Jin Zhang, Jiayun Wu, Caixia Chen, Xiaohui Li, Biwen Xia, Mingtong Xu, and Li Yan

Objectives

A variety of factors differed between rural and urban areas may further influence iodine status and thyroid structure. Hence, this study compared iodine nutrition, the prevalence of thyroid goiter, and nodules between rural and urban residents in Guangzhou, a southern coastal city of China.

Methods

A total of 1211 rural residents and 1305 urban residents were enrolled in this cross-sectional study. A questionnaire regarding personal characteristics was administered. Urinary iodine concentration (UIC) was examined. Ultrasonography of the thyroid was performed to evaluate thyroid goiter and nodules. Multiple logistic analysis was used to identify the potential associated factors.

Results

The median UIC was significantly lower in rural residents than in urban residents (120.80 μg/L vs 136.00 μg/L, P < 0.001). Although the coverage rate of iodized salt was much higher in rural residents than in urban residents (99.59% vs 97.29%, P < 0.001), the percentages of seafood intake (8.60% vs 29.29%, P < 0.001), iodine-containing drug consumption (0.33% vs 1.24%, P = 0.011), and iodine contrast medium injection (0.58% vs 1.87%, P = 0.004) were lower in rural residents than in urban residents. Both the prevalence of thyroid goiters and nodules was significantly higher in rural residents than in urban residents (goiter: 8.06% vs 1.20%, P < 0.001; nodules: 61.89% vs 55.04%, P = 0.023). Living in rural areas was associated with thyroid goiter (OR 5.114, 95% CI 2.893–9.040, P < 0.001).

Conclusions

There were differences in iodine nutrition and the prevalence of thyroid goiter and nodules in rural and urban residents in Guangzhou. Differentiated and specialized monitoring is recommended in our area.

Open access

Josephina G. Kuiper, Aline C. Fenneman, Anne H. van der Spek, Elena Rampanelli, Max Nieuwdorp, Myrthe P.P. van Herk-Sukel, Valery E.p.p. Lemmens, Ernst J. Kuipers, Ron M.C. Herings, and Eric Fliers

Objective: Whether an association between oral levothyroxine use, leading to supraphysiological exposure of the colon to thyroid hormones, and risk of colorectal cancer exists in humans is unclear. We therefore aimed to assess whether the use of levothyroxine is associated with a reduced risk of colorectal cancer in a linked cohort of pharmacy and cancer data.

Design: Population-based matched case-control study.

Methods: A total of 28,121 patients diagnosed with colorectal cancer between 1998-2014 were matched to 106,086 controls. Multivariable logistic regression was used to estimate the association between levothyroxine use and occurrence of colorectal cancer, adjusted for potential confounders. Results were stratified by gender, age, tumour subtype and staging as well as treatment duration and dosing.

Results: A total of 1066 colorectal cancer patients (4%) and 4024 (4%) controls had used levothyroxine at any point before index date (adjusted odds ratio 0.95 [0.88-1.01]). Long-term use of levothyroxine was seen in 323 (30%) colorectal cancer patients and 1111 (28%) controls (adjusted odds ratio 1.00 [0.88-1.13]). Stratification by tumour subsite showed a borderline significant risk reduction of rectal cancer, while this was not seen for proximal colon cancer or distal colon cancer. There was no relationship with treatment duration or with levothyroxine dose.

Conclusions: In this study, no reduced risk of colorectal cancer was seen in levothyroxine users. When stratifying by tumour subsite, a borderline significant risk reduction of rectal cancer was found and may warrant further research.

Open access

Caroline Nguyen, Elisabeth Celestin, Delphine Chambolle, Agnès Linglart, Martin Biosse Duplan, Catherine Chaussain, and Lisa Friedlander

Introduction. X-linked hypophosphatemia (XLH) is a rare, hereditary, and lifelong phosphate wasting disorder characterized by rickets in childhood and impaired teeth mineralization. In the oral cavity, spontaneous abscesses can often occur without any clinical signs of alteration of the causal tooth. The objective of our study was to evaluate the oral care pathway and the oral health-related quality of life (OHRQoL) of patients followed in an expert oral medicine department located within a Parisian hospital and working in close collaboration with an endocrinology department expert in this pathology. Methods. This study employed a qualitative descriptive design including semi-structured interviews using guiding themes. Results. Twenty-one patients were included in the study. The topics brought up exceeded the initial objectives as the patients mostly addressed the alteration of their oral health-related and general quality of life; a very chaotic oral health care pathway with oral health professionals not aware of their pathology; consequences on their social, professional, and school integration. Patients declared the importance of having a multidisciplinary team around them, including medical and dental professionals. Conclusions. The variety of manifestations in patients with XLH necessitates a high coordination of multidisciplinary patient care to optimize quality of life and reduce disease burden. Oral health care pathways are very chaotic for patients who have difficulty finding professionals with sufficient knowledge of the disease. OHRQoL is therefore diminished. This situation improves when patients enter a coordinated care network.