Congenital adrenal hyperplasia (CAH) is one of the most prevalent, and potentially severe, genetic inborn errors of steroid synthesis directly affecting metabolism. Most patients are diagnosed and treated at an early age. There have been very limited reports of adults with CAH-associated adrenal myelolipomas. We aimed to analyze two families with CAH-associated giant adrenal myelolipomas caused by defects in CYP21A2 and CYP17A1 genes. A total of 14 individuals from two unrelated families were identified with either CYP21A2 or CYP17A1 mutations. Of note, five patients were found with adrenal myelolipomas. Total DNA isolated from the peripheral blood of the two probands was screened for potential mutations in the following susceptibility genes of CAH: CYP21A2, CYP11B1, CYP17A1, HSD17B3, HSD3B2, ARMC5, and STAR using target capture-based deep sequencing; and Sanger sequencing was conducted for the family members to detect the potential mutations. The following results were obtained. In family 1, molecular genetics sequencing revealed a compound heterozygous mutation (c.293-13C>G/c.518T>A, p.I173N) in CYP12A2 in the patient and his brother. In family 2, all three female patients with adrenal myelolipomas were found to have a compound heterozygous mutation (c.1118A>T, p.H373L/c.1459_1467del9, p.D487_F489del) in CYP17A1. To avoid giant CAH-associated adrenal myelolipomas in adults, it is important to identify CAH early so that appropriate treatment can be initiated to interrupt the chronic adrenal hyperstimulation resulting from increased ACTH. Genetic testing and counseling could be useful in CAH.
Qiuli Liu, Lin-ang Wang, Jian Su, Dali Tong, Weihua Lan, Luofu Wang, Gaolei Liu, Jun Zhang, Victor Wei Zhang, Dianzheng Zhang, Rongrong Chen, Qingyi Zhu, and Jun Jiang
Qiuli Liu, Gang Yuan, Dali Tong, Gaolei Liu, Yuting Yi, Jun Zhang, Yao Zhang, Lin-ang Wang, Luofu Wang, Dianzheng Zhang, Rongrong Chen, Yanfang Guan, Xin Yi, Weihua Lan, and Jun Jiang
Von Hippel–Lindau (VHL) disease manifests as a variety of benign and malignant neoplasms. Previous studies of VHL disease have documented several genotype–phenotype correlations; however, many such correlations are still unknown. Increased identification of new mutations and patients with previously described mutations will allow us to better understand how VHL mutations influence disease phenotypes.
Patients and design
A total of 45 individuals from five unrelated families were evaluated, of which 21 patients were either diagnosed with VHL disease or showed strong evidence related to this disease. We compared the patients’ gene sequencing results with their medical records including CT or MRI scans, eye examinations and laboratory/pathological examinations. Patients were also interviewed to obtain information regarding their family history.
We identified four missense mutations: c.239G>T (p.Ser80Ile), linked with VHL Type 2B, was associated with renal cell carcinoma, pheochromocytoma and hemangioma in the cerebellum; c.232A>T (p.Asn78Tyr) manifested as RCC alone and likely caused VHL Type 1; c.500G>A (p.Arg167Gln) mutation was more likely to cause VHL Type 2 than Type 1 as it preferentially induced Pheo and HB in the retina, cerebellum and spinal cord; c.293A>G (p.Try98Cys) was associated with Pheo and thus likely induced VHL Type 2.
Characterizing VHL disease genotype–phenotype correlations can enhance the ability to predict the risk of individual patients developing different VHL-related phenotypes. Ultimately, such insight will improve the diagnostics, surveillance and treatment of VHL patients.
Four missense mutations in VHL have been identified in 21 individuals when five unrelated Chinese families with VHL disease were analyzed; VHL mutations are highly associated with unique disease phenotypes.
Yiqiang Huang, Lin-ang Wang, Qiubo Xie, Jian Pang, Luofu Wang, Yuting Yi, Jun Zhang, Yao Zhang, Rongrong Chen, Weihua Lan, Dianzheng Zhang, and Jun Jiang
Pheochromocytoma and paragangliomas (PCC/PGL) are neuroendocrine tumors that arise from chromaffin cells of the adrenal medulla and sympathetic/parasympathetic ganglia, respectively. Of clinical relevance regarding diagnosis is the highly variable presentation of symptoms in PCC/PGL patients. To date, the clear-cut correlations between the genotypes and phenotypes of PCC/PGL have not been entirely established. In this study, we reviewed the medical records of PCC/PGL patients with pertinent clinical, laboratory and genetic information. Next-generation sequencing (NGS) performed on patient samples revealed specific germline mutations in the SDHB (succinate dehydrogenase complex iron-sulfur subunit B) and SDHD (succinate dehydrogenase complex subunit D) genes and these mutations were validated by Sanger sequencing. Of the 119 patients, two were identified with SDHB mutation and one with SDHD mutation. Immunohistochemical (IHC) staining was used to analyze the expression of these mutated genes. The germline mutations identified in the SDH genes were c343C>T and c.541-542A>G in the SDHB gene and c.334-337delACTG in the SDHD gene. IHC staining of tumors from the c.343C>T and c.541-2A>G carriers showed positive expression of SDHB. Tumors from the c.334-337delACTG carrier showed no expression of SDHD and a weak diffused staining pattern for SDHB. We strongly recommend genetic testing for suspected PCC/PGL patients with a positive family history, early onset of age, erratic hypertension, recurrence or multiple tumor sites and loss of SDHB and/or SDHD expression. Tailored personal management should be conducted once a patient is confirmed as an SDHB and/or SDHD mutation carrier or diagnosed with PCC/PGL.
Xue-Lian Zhang, Xinyi Zhao, Yong Wu, Wen-qing Huang, Jun-jiang Chen, Peijie Hu, Wei Liu, Yi-Wen Chen, Jin Hao, Rong-Rong Xie, Hsiao Chang Chan, Ye Chun Ruan, Hui Chen, and Jinghui Guo
The beneficial effect of angiotensin(1–7) (Ang(1–7)), via the activation of its receptor, MAS-1, has been noted in diabetes treatment; however, how Ang(1–7) or MAS-1 affects insulin secretion remains elusive and whether the endogenous level of Ang(1–7) or MAS-1 is altered in diabetic individuals remains unexplored. We recently identified an important role of cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated Cl− channel, in the regulation of insulin secretion. Here, we tested the possible involvement of CFTR in mediating Ang(1–7)’s effect on insulin secretion and measured the level of Ang(1–7), MAS-1 as well as CFTR in the blood of individuals with or without type 2 diabetes.
Ang(1–7)/MAS-1/CFTR pathway was determined by specific inhibitors, gene manipulation, Western blotting as well as insulin ELISA in a pancreatic β-cell line, RINm5F. Human blood samples were collected from 333 individuals with (n = 197) and without (n = 136) type 2 diabetes. Ang(1–7), MAS-1 and CFTR levels in the human blood were determined by ELISA.
In RINm5F cells, Ang(1–7) induced intracellular cAMP increase, cAMP-response element binding protein (CREB) activation, enhanced CFTR expression and potentiated glucose-stimulated insulin secretion, which were abolished by a selective CFTR inhibitor, RNAi-knockdown of CFTR, or inhibition of MAS-1. In human subjects, the blood levels of MAS-1 and CFTR, but not Ang(1–7), were significantly higher in individuals with type 2 diabetes as compared to those in non-diabetic healthy subjects. In addition, blood levels of MAS-1 and CFTR were in significant positive correlation in type-2 diabetic but not non-diabetic subjects.
These results suggested that MAS-1 and CFTR as key players in mediating Ang(1–7)-promoted insulin secretion in pancreatic β-cells; MAS-1 and CFTR are positively correlated and both upregulated in type 2 diabetes.