ABSTRACT
Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome in which tumor-induced osteochondrosis is a metabolic bone disease caused by increased renal excretion of phosphorus due to excessive secretion of fibroblast growth factor 23 (FGF23) by tumor tissue. We report here a rare case of TIO in which the tumor was found in the hyoid body and the patient had tertiary hyperparathyroidism. The patient's symptoms did not improve after removal of the tumor from the hyoid body, and the patient's hypophosphatemia was gradually improved after subsequent removal of the left parathyroid gland. TIO derived from the tongue tumor is very rare, and also subsequent tertiary hyperparathyroidism is even rarer. This report helps to improve the understanding of TIO and provides reference in the diagnosis and treatment of TIO.
Subject(s)
Hyperparathyroidism , Osteomalacia , Paraneoplastic Syndromes , Humans , Paraneoplastic Syndromes/etiology , Osteomalacia/etiology , Parathyroid GlandsABSTRACT
Two patients with Gitelman syndrome were admitted to the Department of Endocrinology, Third Xiangya Hospital of Central South University. The genomic DNA from the patients' peripheral blood was extracted and the whole-exome sequencing was performed to detect the possible mutations. The function of the mutation sites was analyzed by bioinformatics software. Through whole-exome sequencing and Sanger sequencing, we have found that 2 patients with Gitelman syndrome carried compound heterozygous mutations of SLC12A3 gene, which were c.486_490delTACGGinsA, p.R943W, p.D486N, and p.R928C. Among them, c.486_490delTACGGinsA insertion deletion mutation causes frame shift and protein truncation. The p.R943W, p.D486N, and p.R928C of SLC12A3 gene were predicted to be pathogenic mutations by SIFT, PolyPhen2, and Mutation Taster. These 4 mutations were all reported, but p.R943W was first reported in Chinese population. Gitelman syndrome is rare in clinic and the rate of missed diagnosis is high. Early genetic analysis in patients with Gitelman syndrome is helpful to determine the etiology and guide the treatment.
Subject(s)
Gitelman Syndrome , Genetic Testing , Gitelman Syndrome/diagnosis , Gitelman Syndrome/genetics , Humans , Mutation , Pedigree , Solute Carrier Family 12, Member 3/genetics , Exome SequencingABSTRACT
Multiple endocrine neoplasia-IIb (MEN-IIb) is a rare hereditary autosomal dominant syndrome caused by mutations in the RET proto-oncogene. It's characterized by medullary thyroid carcinoma (MTC), pheochromocytoma (PHEO), mucosal neuromas, and Marfanoid habitus. Because of the rarity of MEN-IIb and finiteness of clinical cognition, the majority of the patients suffer a delayed diagnosis. A MEN-IIb patient with the lingual mucosal neuromas since childhood was admitted in the Third Xiangya Hospital of Central South University in November, 2018. He had surgical history of mitral valve prolapse and spinal deformity. He was diagnosed with MTC and PHEO at the age of 22 and 28, respectively, and received surgical treatments. Sequencing of RET gene revealed a de novo heterozygous p.M918T mutation in the patient. Being aware of the unique clinical phenotype and screening of RET gene mutation may lead to the early diagnosis and better long-term outcome for MEN-IIb.
Subject(s)
Adrenal Gland Neoplasms , Multiple Endocrine Neoplasia Type 2a , Multiple Endocrine Neoplasia Type 2b , Multiple Endocrine Neoplasia , Thyroid Neoplasms , Child , Genes , Humans , Male , Multiple Endocrine Neoplasia Type 2a/genetics , Multiple Endocrine Neoplasia Type 2b/genetics , Mutation , Proto-Oncogene Mas , Proto-Oncogene Proteins c-ret/genetics , Thyroid Neoplasms/geneticsABSTRACT
Kallmann syndrome (KS) is a rare developmental disorder that manifests as congenital hypogonadotropic hypogonadism with anosmia. More than 19 genes have been found to be associated with KS. However, approximately 70% of the causes of KS remain unclear. Here, we studied seven KS patients, from three families, who had delayed puberty and olfactory bulb dysplasia. However, the families of these patients showed a range of other unique clinical features, including hearing loss, anosmia (to varying degrees) and unilateral renal agenesis. We performed whole exome sequencing and copy number variation (CNV) sequencing on samples acquired from these patients. We identified two novel mutations (c.844delC in ANOS1, c.475C>T in SOX10) and a novel trigenic pattern, PROKR2/CHD7/FEZF1 (c.337T>C in PROKR2, c.748C>G in FEZF1, c.8773G>A in CHD7). The c.844delC mutation in the ANOS1 gene was predicted to generate a truncated form of the anosmin-1 protein. SIFT and PolyPhen-2 predicted that the c.475C>T mutation in SOX10 had a damaging effect. The PROKR2 mutation (c.337T>C) was previously reported as harmful. No pathogenic copy number alterations were detected. Our study expands the genotypic and phenotypic spectrum of KS, a disease that shows considerable clinical and genetic heterogeneity. The application of whole exome sequencing could facilitate our understanding of the pathogenesis of KS.
Subject(s)
Hypogonadism , Kallmann Syndrome , China , DNA Copy Number Variations , Humans , Hypogonadism/genetics , Kallmann Syndrome/genetics , Mutation , Pedigree , Exome SequencingABSTRACT
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant inherited endocrine tumor syndrome caused by inactivating variants of the MEN1 gene. The aim of this study is to explore the clinical and genetic characteristics of four MEN1 patients. We isolated genomic deoxyribonucleic acid from lymphocytes, parathyroid, and thymic tumoral tissue specimens from the MEN1 patients. All exons of the MEN1 and CDNK1B genes and adjacent exon-intron sequences were amplified by polymerase chain reaction and subsequently sequenced. Further, the splice alterations were studied by sequencing the amplified RT-PCR products for MEN1 cDNA. We identified four heterozygous MEN1 germline variants: c.564delC, c.1268G>A, IVS5+5delG, and c.1546_1547insC. Both c.564delC and IVS5+5delG were novel variants. The impact of the MEN1 splice variant, IVS5+5delG, was evaluated using bioinformatics and in vitro analyses. The analyses indicated that this variant resulted in skipping of the neighboring exon and was disease-causing. Two novel somatic variants, c.249_252delGTCT and c.313_314insC, were found. Additionally, loss of heterozygosity (LOH) for the MEN1 locus (IVS5+5delG and c.564delC) was found in tumor tissue samples from the MEN1 patients, consistent with Knudson's two-hit mechanism. We identified four MEN1 germline variants and two novel somatic variants. Early recognition of the phenotype coupled with variant screening of the MEN1 gene is the key to diagnosing and treating MEN1 effectively at an early stage.
Subject(s)
Multiple Endocrine Neoplasia Type 1/pathology , Mutation , Phenotype , Proto-Oncogene Proteins/genetics , Adult , Female , Humans , Male , Middle Aged , Multiple Endocrine Neoplasia Type 1/geneticsABSTRACT
INTRODUCTION: Metabolic surgery is an effective treatment for type 2 diabetes (T2D). At present, there is no authoritative standard for predicting postoperative T2D remission in clinical use. In general, East Asian patients with T2D have a lower body mass index and worse islet function than westerners. We aimed to look for clinical predictors of T2D remission after metabolic surgery in Chinese patients, which may provide insights for patient selection. METHODS: Patients with T2D who underwent metabolic surgery at the Third Xiangya Hospital between October 2008 and March 2017 were enrolled. T2D remission was defined as an HbA1c level below 6.5% and an FPG concentration below 7.1 mmol/L for at least one year in the absence of antidiabetic medications. RESULTS: (1) Independent predictors of short-term T2D remission (1-2 years) were age and C-peptide area under the curve (C-peptide AUC); independent predictors of long-term T2D remission (4-6 years) were C-peptide AUC and fasting plasma glucose (FPG). (2) The optimal cutoff value for C-peptide AUC in predicting T2D remission was 30.93 ng/ml, with a specificity of 67.3% and sensitivity of 75.8% in the short term and with a specificity of 61.9% and sensitivity of 81.5% in the long term, respectively. The areas under the ROC curves are 0.674 and 0.623 in the short term and long term, respectively. (3) We used three variables (age, C-peptide AUC, and FPG) to construct a remission prediction score (ACF), a multidimensional 9-point scale, along which greater scores indicate a better chance of T2D remission. We compared our scoring system with other reported models (ABCD, DiaRem, and IMS). The ACF scoring system had the best distribution of patients and prognostic significance according to the ROC curves. CONCLUSION: Presurgery age, C-peptide AUC, and FPG are independent predictors of T2D remission after metabolic surgery. Among these, C-peptide AUC plays a decisive role in both short- and long-term remission prediction, and the optimal cutoff value for C-peptide AUC in predicting T2D remission was 30.93 ng/ml, with moderate predictive values. The ACF score is a simple reliable system that can predict T2D remission among Chinese patients.
ABSTRACT
BACKGROUND: Primary bilateral macronodular adrenal hyperplasia is a rare cause of Cushing's syndrome characterized by the presence of bilateral secretory adrenal nodules. Recent studies have shown that primary bilateral macronodular adrenal hyperplasia is caused by combined germline and somatic mutations of the ARMC5 gene. Exophthalmos is an underappreciated sign of Cushing's syndrome. CASE PRESENTATION: A 52-year-old Chinese woman with progressively worsening bilateral proptosis presented to our hospital. Subsequently she was diagnosed as having primary bilateral macronodular adrenal hyperplasia and underwent bilateral laparoscopic adrenalectomy. Genomic deoxyribonucleic acid was isolated from lymphocytes as well as seven different adrenal nodules and the ARMC5 sequence was determined by Sanger sequencing. We identified one heterozygous ARMC5 germline mutation c.682C>T (p. Gln228*) and five heterozygous somatic mutations (c.310delG, c.347_357del11, c.267delC, c.283_289del7, and c.205-322del118) in five different adrenal nodules. All mutations are novel and were not found in any of the available online databases. To test whether the ARMC5 mutation induced messenger ribonucleic acid decay, real-time reverse transcriptase polymerase chain reaction was performed on patient and control adrenal tissue. We found that the adrenal cortex of our patient showed a low ARMC5 messenger ribonucleic acid expression compared with normal adrenal cortex, possibly as a result of nonsense-mediated messenger ribonucleic acid decay CONCLUSIONS: We demonstrated extensive genetic diversity of ARMC5 in a patient with primary bilateral macronodular adrenal hyperplasia that started with exophthalmos, which contributes to further understanding of the pathogenesis of this disease. Early recognition of atypical symptoms and screening for ARMC5 mutation in patients with primary bilateral macronodular adrenal hyperplasia has important clinical implications for the diagnosis and genetic counseling.
Subject(s)
Cushing Syndrome/genetics , Germ-Line Mutation , Tumor Suppressor Proteins/genetics , Adrenal Gland Neoplasms/diagnostic imaging , Adrenal Gland Neoplasms/genetics , Adrenal Gland Neoplasms/pathology , Adrenal Gland Neoplasms/surgery , Adrenal Glands/diagnostic imaging , Adrenal Glands/surgery , Armadillo Domain Proteins , Cushing Syndrome/diagnosis , Exophthalmos/etiology , Female , Humans , Middle Aged , Physical Examination , Tomography, X-Ray ComputedABSTRACT
The metabolic syndrome (MS) is a cluster of metabolic disorders arising from insulin resistance, characterized by the presence of central obesity, impaired fasting glucose level, dyslipidemia and hypertension. As the first-line medication, metformin is commonly used for MS to reduce insulin resistance. Comparing with rosiglitazone, metformin does not increase cardiovascular mortality risk in patients with MS. However, metformin is not good enough in improving insulin sensitivity. Its molecular mechanism is still not clear. Recent studies have demonstrated that resistin, an adipokine, could induce IR by both AMPK-dependent and AMPK-independent pathways. Though there were conflicting findings of resistin in metabolic syndrome or type 2 diabetes mellitus in different studies, resistin was significant decreased in the rosiglitazone treated patients than in the metformin-treated patients in most of studies. Here, we hypothesized that resistin, an adipokine, may affect the improvement of insulin sensitivity in the metabolic syndrome patient treated with metformin. This hypothesis could explain why rosiglitazone is superior to metformin in enhancement of insulin sensitivity.
Subject(s)
Insulin Resistance/physiology , Metabolic Syndrome/drug therapy , Metformin/therapeutic use , Resistin/physiology , Humans , Metformin/metabolism , Models, Biological , Resistin/metabolism , Rosiglitazone , Thiazolidinediones/therapeutic useABSTRACT
The purpose of this study was to identify the underlying genetic cause in a four generation Chinese family diagnosed with mucopolysaccharidosis type II. Peripheral blood samples were collected from family members and the iduronate-2-sulfatase (IDS) gene was analyzed by DNA sequencing. The impact of IDS mutations on mRNA transcription was determined by quantitative real-time RT-PCR (qRT-PCR) in both patients as well as in healthy control samples. In addition, RT-PCR was performed to confirm the characteristics of a found mutation located in non-canonical splicing site. A 3' splice site mutation c.880-8A>G (IVS 6-8A>G) was identified in two members of the analyzed MPS II family and sequencing of RT-PCR products showed that this mutation activates an upstream cryptic splice-site in intron 6, leads to the 7 nucleotide insertion in exon 7, which in turn results in an exon 7 frameshift introducing a premature stop codon and shorter peptide chain. In addition, qRT-PCR products from the two patients showed a reduced IDS mRNA expression (43.9% and 71.2%, respectively), when compared with the average IDS mRNA expression in healthy control samples, possibly as a result of nonsense-mediated mRNA decay. In conclusion, in this study, we have identified an IDS gene splice mutation which is associated with clinically attenuated MPS II phenotype. In addition, our study accentuates the importance of cDNA analysis in the detection of intronic mutations, since in the studies examining only gDNA, the link between genotype and phenotype may have been misinterpreted.
Subject(s)
Glycoproteins/genetics , Mucopolysaccharidosis II/genetics , Point Mutation , RNA Splice Sites , Adult , Asian People , Base Sequence , Case-Control Studies , Child, Preschool , Codon, Nonsense , Consanguinity , DNA Mutational Analysis , Female , Gene Expression , Genetic Association Studies , Glycoproteins/metabolism , Humans , Introns , Male , Mucopolysaccharidosis II/diagnostic imaging , Mucopolysaccharidosis II/enzymology , Pedigree , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Radiography , Real-Time Polymerase Chain ReactionABSTRACT
AIM: To construction of eukaryotic expression vector of human TSARG4 and establishment of its stable transfected Hela cell line. METHODS: The open reading frame (ORF) of TSARG4 was amplified from human testis by RT-PCR. The PCR products were cloned into pUCm-T vectors and sequenced. Then the cDNA fragment was subcloned into pcDNA3.1(+), a eukaryotic expression vector. The recombined plasmid pcDNA3.1(+)/TSARG4 was sequenced and transfected into Hela cell by lipofectamine 2000. After screening culture by G418, stable transfected HeLa cell line was established, and the expression of TSARG4 was identified by RT-PCR and in situ hybridization. RESULTS: The eukaryotic expression plasmid of pcDNA3.1(+)/TSARG4 was successfully constructed and stable transfected HeLa cell line was established. RT-PCR and in situ hybridization result revealed that TSARG4 was expressed successfully in HeLa cells. CONCLUSION: The recombinant eukaryotic expression vector of pcDNA3.1(+)/TSARG4 has been constructed successfully and stably expressed in HeLa cell line, providing a foundation for further studies on the function of TSARG4 in vitro.
Subject(s)
Cell Line , Gene Expression , Genetic Vectors/genetics , Proteins/genetics , Transfection , Eukaryota/genetics , Eukaryota/metabolism , Genetic Vectors/metabolism , HeLa Cells , Humans , Membrane Proteins , Proteins/metabolismABSTRACT
OBJECTIVE: To determine the effect of different concentrations of glucose on the differentiation of 3T3-L(1) and the expression of insig-1 and insig-2 mRNA, and to explore the effect of insulin-induced gene in the differentiation and formation of adipocytes and lipogenesis. METHODS: The 3T3-L(1) cells were induced to differentiate in high glucose concentration (25 mol/L G.S), low glucose concentration (5.5 mol/L G.S), and mannitol (19.5 mol/L Mannitol +5.5 mol/L G.S), respectively. The differentiation of 3T3-L(1) cells was examined by oil red "O" straining, and the expression of insig-1,insig-2 mRNA and AP2 mRNA was examined by RT-PCR and in situ hybridization. RESULTS: With the differentiation of 3T3-L(1) cells, the expression of insig-1 and insig-2 mRNA was gradually up-regulated. The expression of insig-1 and insig-2 mRNA significantly increased while AP(2) mRNA decreased in the low glucose concentration inducing group and mannitol inducing group. In the high glucose concentration inducing group, the cell differentiation was poor (P<0.05). There was no difference between the low glucose concentration and the mannitol group in the differentiation of 3T3-L(1) cells, and in the expression of insig-1 and insig-2 and AP(2) mRNA. CONCLUSION: Different concentrations of glucose may influence the cell differentiation and the low glucose concentration promotes insig-1 and insig-2 gene expression, which may lead to the inhibition of the differentiation and lipogenesis of preadipocytes.
Subject(s)
Cell Differentiation/drug effects , Glucose/pharmacology , Membrane Proteins/biosynthesis , RNA, Messenger/biosynthesis , 3T3-L1 Cells , Animals , Dose-Response Relationship, Drug , Membrane Proteins/genetics , Mice , RNA, Messenger/geneticsABSTRACT
AIM: To construct the eukaryotic expression plasmid of insig2 gene and detect the expression of downstream gene adiponectin and adipocyte fatty acid-binding protein 2 (AP2) after the transfection of 3T3-L1 cells. METHODS: Insig2 gene of the mouse was amplified by RT-PCR and then cloned into the eukaryon expression vector pEGFP-C(3), After confirmed by double restriction enzyme digestion analysis and DNA sequencing, pEGFP-C(3)-insig2 was transfected into 3T3-L1 cells by lipofectamine 2000. The expression of insig2 and downstream gene in the 3T3-L1 cells were detected by RT-PCR and fluorescence microscope. RESULTS: The eukaryotic expression plasmid of pEGFP-C(3)-insig2 was constructed. The expression of fusion protein in the endochylema was confirmed. The transcription of adiponectin mRNA and AP2 mRNA was down-regulated after transfection for 24 h and 72 h. CONCLUSION: The eukaryotic expression plasmid of pEGFP-C(3)-insig2 is successfully constructed. The transfected insig2 may have an effect on fat metabolism of 3T3-L1 cells.