Exosomal MALAT1 from macrophages treated with high levels of glucose upregulates LC3B expression via miR-204-5p downregulation.

BACKGROUND: Metastasis-associated lung adenocarcinoma transcript 1 ( MALAT1 ) plays a critical role in the pathophysiology of diabetes-related complications. However, whether macrophage-derived MALAT1 affects autophagic activity under hyperglycemic conditions is unclear. Therefore, we investigated the molecular regulatory mechanisms of macrophage-derived MALAT1 and autophagy under hyperglycemic conditions. METHODS: Hyperglycemia was induced by culturing macrophages in 25 mM glucose for 1 hour. Exosomes were extracted from the culture media. A rat model of carotid artery balloon injury was established to assess the effect of MALAT1 on vascular injury. Reverse transcription, real-time quantitative polymerase chain reaction, western blotting, immunohistochemical staining, and luciferase activity assays were performed. RESULTS: Stimulation with high levels of glucose significantly enhanced MALAT1 expression in macrophage-derived exosomes. MALAT1 inhibited miR-204-5p expression in macrophage-derived exosomes under hyperglycemic conditions. siRNA-induced silencing of MALAT1 significantly reversed macrophage-derived exosome-induced miR-204-5p expression. Hyperglycemic treatment caused a significant, exosome-induced increase in the expression of the autophagy marker LC3B in macrophages. Silencing MALAT1 and overexpression of miR-204-5p significantly decreased LC3B expression induced by macrophage-derived exosomes. Overexpression of miR-204-5p significantly reduced LC3B luciferase activity induced by macrophage-derived exosomes. Balloon injury to the carotid artery in rats significantly enhanced MALAT1 and LC3B expression, and significantly reduced miR-204-5p expression in carotid artery tissue. Silencing MALAT1 significantly reversed miR-204-5p expression in carotid artery tissue after balloon injury. MALAT1 silencing or miR-204-5p overexpression significantly reduced LC3B expression after balloon injury. CONCLUSION: This study demonstrated that hyperglycemia upregulates MALAT1 . MALAT1 suppresses miR-204-5p expression and counteracts the inhibitory effect of miR-204-5p on LC3B expression in macrophages to promote vascular disease.

Exosomal MALAT1 Derived from High Glucose-Treated Macrophages Up-Regulates Resistin Expression via miR-150-5p Downregulation.

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) plays a crucial role in the pathophysiological process associated with diabetes-related complications. The effect of high glucose levels on macrophage-derived exosomal MALAT1 is unknown. Therefore, we investigated the molecular regulatory mechanisms controlling exosomal MALAT1 in macrophages under high glucose treatment and the therapeutic target of macrophage-derived exosomal MALAT1 using a balloon injury model of vascular disease in diabetic rats. High glucose (25 mM) significantly increased MALAT1 expression in macrophage-derived exosomes. MALAT1 suppressed miR-150-5p expression in macrophage-derived exosomes under high-glucose conditions. Silencing MALAT1 using MALAT1 siRNA significantly reversed miR-150-5p expression induced by macrophage-derived exosomes. Macrophage-derived exosomes under high-glucose treatment significantly increased resistin expression in macrophages. Silencing MALAT1 and overexpression of miR-150-5p significantly decreased resistin expression induced by macrophage-derived exosomes. Overexpression of miR-150-5p significantly decreased resistin luciferase activity induced by macrophage-derived exosomes. Macrophage-derived exosome significantly decreased glucose uptake in macrophages and silencing MALAT1, resistin or overexpression of miR-150-5p significantly reversed glucose uptake. Balloon injury to the carotid artery significantly increased MALAT1 and resistin expression and significantly decreased miR-150-5p expression in arterial tissue. Silencing MALAT1 significantly reversed miR-150-5p expression in arterial tissue after balloon injury. Silencing MALAT1 or overexpression of miR-150-5p significantly reduced resistin expression after balloon injury. In conclusion, high glucose up-regulates MALAT1 to suppress miR-150-5p expression and counteracts the inhibitory effect of miR-150-5p on resistin expression in macrophages to promote vascular disease. Macrophage-derived exosomes containing MALAT1 may serve as a novel cell-free approach for the treatment of vascular disease in diabetes mellitus.

Chrysin boosts KLF2 expression through suppression of endothelial cell-derived exosomal microRNA-92a in the model of atheroprotection.

PURPOSE: Atherosclerosis and its related clinical complications are the leading cause of death. MicroRNA (miR)-92a in the inflammatory endothelial dysfunction leads to atherosclerosis. Krüppel-like factor 2 (KLF2) is required for vascular integrity and endothelial function maintenance. Flavonoids possess many biological properties. This study investigated the vascular protective effects of chrysin in balloon-injured carotid arteries. MATERIALS AND METHODS: Exosomes were extracted from human coronary artery endothelial cell (HCAEC) culture media. Herb flavonoids and chrysin were the treatments in these atheroprotective models. Western blotting and real-time PCRs were performed. In situ hybridization, immunohistochemistry, and immunofluorescence analyses were employed. RESULTS: MiR-92a increased after balloon injury and was present in HCAEC culture media. Chrysin was treated, and significantly attenuated the miR-92a levels after balloon injury, and similar results were obtained in HCAEC cultures in vitro. Balloon injury-induced miR-92a expression, and attenuated KLF2 expression. Chrysin increased the KLF2 but reduced exosomal miR-92a secretion. The addition of chrysin and antagomir-92a, neointimal formation was reduced by 44.8 and 49.0% compared with balloon injury after 14 days, respectively. CONCLUSION: Chrysin upregulated KLF2 expression in atheroprotection and attenuated endothelial cell-derived miR-92a-containing exosomes. The suppressive effect of miR-92a suggests that chrysin plays an atheroprotective role. Proposed pathway for human coronary artery endothelial cell (HCAEC)-derived exosomes induced by chrysin to suppress microRNA (miR)-92a expression and counteract the inhibitory effect of miR-92a on KLF2 expression in HCAECs. This provides an outline of the critical role of the herbal flavonoid chrysin, which may serve as a valuable therapeutic supplement for atheroprotection.

Hyperbaric oxygen-induced long non-coding RNA MALAT1 exosomes suppress MicroRNA-92a expression in a rat model of acute myocardial infarction.

Hyperbaric oxygen (HBO) improves angiogenesis. The effect of HBO on metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a pro-angiogenic long non-coding RNA, in cardiac myocyte-derived exosomes and acute myocardial infarction (AMI) is unknown. We aimed to investigate whether MALAT1 is altered in cardiac myocyte-derived exosomes in response to HBO as well as the molecular regulatory mechanisms of MALAT1 in cardiac myocytes treated with HBO. Cardiac myocytes were cultured, and HBO was applied at 2.5 atmosphere absolute in a hyperbaric chamber. Exosomes were extracted from the culture media. A rat model of AMI generated by the ligation of the left anterior descending artery was used. HBO significantly increased MALAT1 expression in cardiac myocytes and HBO-induced MALAT1 and exosomes attenuated miR-92a expression after myocardial infarction. Expression of krüppel-like factor 2 (KLF2) and CD31 was significantly decreased after infarction and HBO-induced exosomes significantly reversed the expression. Silencing of MALAT1 using MALAT1-locked nucleic acid GapmeR significantly attenuated KLF2 and CD31 protein expression after infarction induced by HBO-induced exosomes. HBO-induced exosomes also decreased infarct size significantly. HBO-induced exosomes from cardiac myocytes up-regulate MALAT1 to suppress miR-92a expression and counteract the inhibitory effect of miR-92a on KLF2 and CD31 expression in left ventricular myocardium after myocardial infarction to enhance neovascularization.

(-)-Epigallocatechin Gallate Promotes MicroRNA 145 Expression against Myocardial Hypoxic Injury through Dab2/Wnt3a/ß-catenin.

MicroRNA 145 (miR-145) is a critical modulator of cardiovascular diseases. The downregulation of myocardial miR-145 is followed by an increase in disabled-2 (Dab2) expression in cardiomyocytes. (-)-epigallocatechin gallate (EGCG) is a flavonoid that has been evaluated extensively due to its diverse pharmacological properties including anti-inflammatory effects. The aim of this study was to investigate the cardioprotective effects of EGCG under hypoxia-induced stress in vitro and in vivo. The hypoxic insult led to the suppression of miR-145 expression in cultured rat cardiomyocytes in a concentration-dependent manner. Western blotting and real-time PCR were performed. In rat myocardial infarction study, in situ hybridization, and immunofluorescent analyses were adopted. The western blot and real-time PCR data revealed that hypoxic stress with 2.5% O2 suppressed the expression of miR-145 and Wnt3a/ß-catenin in cultured rat cardiomyocytes but augmented Dab2. Treatment with EGCG attenuated Dab2 expression, but increased Wnt3a and ß-catenin in hypoxic cultured cardiomyocytes. Following in vivo myocardial infarction (MI) study, the data revealed the myocardial infarct area reduced by 48.5%, 44.6%, and 48.5% in EGCG (50mg/kg) or miR-145 dominant or Dab2 siRNA groups after myocardial infarction for 28 days, respectively. This study demonstrated that EGCG increased miR-145, Wnt3a, and ß-catenin expression but attenuated Dab2 expression. Moreover, EGCG ameliorated myocardial ischemia in vivo. The novel suppressive effect was mediated through the miR-145 and Dab2/Wnt3a/ß-catenin pathways.

Catalpol Ameliorates Neointimal Hyperplasia in Diabetic Rats.

Catalpol, an iridoid glycoside, is an isolated natural product of Rehmannia glutinosa, which has been reported to have antidiabetic properties. This study investigated the vascular protective effects of catalpol in hyperglycemic rats with balloon-injured carotid arteries. Balloon injury stress led to the upregulation of monocyte chemoattractant protein-1 expression in rats with streptozotocin-induced diabetes. Western blotting and real-time PCR were performed. In situ hybridization, immunohistochemistry, and confocal analyses were employed. Monocyte chemoattractant protein-1 levels were increased through streptozotocin induction or balloon injury. After treatment with catalpol, the neointimal hyperplasia area was reduced 2 weeks after balloon injury in hyperglycemic rats. Real-time PCR and immunohistochemical analysis demonstrated reduced levels of monocyte chemoattractant protein-1 2 weeks after the balloon injury. Monocyte chemoattractant protein-1 expression was significantly increased in balloon-injured rats compared with the control groups. Thus, treatment with catalpol affected monocyte chemoattractant protein-1 expression. This study demonstrated that catalpol downregulated monocyte chemoattractant protein-1 expression in carotid arteries and ameliorated neointimal hyperplasia in hyperglycemic rats. The suppressive effect of monocyte chemoattractant protein-1 suggests that it plays a key role in neointimal hyperplasia. The results imply that catalpol is potentially effective for preventing hyperglycemia-related ischemic cardiac diseases.

Hyperbaric oxygen boosts long noncoding RNA MALAT1 exosome secretion to suppress microRNA-92a expression in therapeutic angiogenesis.

BACKGROUND: Hyperbaric oxygen (HBO) could improve wound healing by enhancement of angiogenesis. The effect of HBO on metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a proangiogenic long noncoding RNA, and on endothelial cell-derived exosome is unknown. We aim to investigate both whether MALAT1 is altered in human coronary artery endothelial cells (HCAECs)-derived exosomes in response to HBO as well as the molecular regulatory mechanisms of MALAT1 in HCAECs under HBO treatment. METHODS AND RESULTS: HCAECs were cultured and HBO was applied at 2.5 atmosphere absolute (ATA) in a hyperbaric chamber. Exosomes were extracted from culture media. A rat model of hind-limb ischemia was performed by ligation of the right femoral artery. HBO at 2.5 ATA significantly increased MALAT1 expression in HCAECs and HCAECs-derived exosomes. MALAT1 suppressed miR-92a expression in HCAEC-derived exosomes under HBO. Silencing MALAT1 by MALAT1 siRNA significantly inhibited KLF2 mRNA expression induced by HBO, as did MiR-92a. MiR-92a significantly decreased KLF2 luciferase activity in HCAECs under HBO. HBO and HBO-induced exosomes significantly increased cell proliferation and the capillary-like network formation of HCAECs. MALAT1 siRNA and miR-92a overexpression significantly attenuated the cell proliferation and tube formation caused by HBO-induced exosome. HBO and HBO-induced exosomes significantly improved neovascularization in a rat model of hind-limb ischemia. CONCLUSIONS: HBO upregulates MALAT1 to suppress miR-92a expression and counteracts the inhibitory effect of miR-92a on KLF2 expression in HCAECs to enhance neovascularization. HBO-induced derivation of exosomes from HCAECs enhances angiogenesis. Exosomes containing MALAT1 might serve as a valuable therapeutic tool for neovascularization by HBO.

Effects of flavonoids on MicroRNA 145 regulation through Klf4 and myocardin in neointimal formation in vitro and in vivo.

MicroRNA 145 (miR-145) is a critical modulator of vascular smooth muscle cell (VSMC) phenotyping and proliferation. Flavonoids have been studied extensively due to their diverse pharmacological properties, including anti-inflammatory effects. The aims of this study is designed to evaluate the atheroprotective effects on angiotensin II (Ang II)-induced miR-145 and Klf4/myocardin expression in vitro and in vivo of flavonoids, including (-)-epigallocatechin gallate (EGCG), chrysin, wogonin, silibinin, and ferulic acid. Ang II significantly reduced the miR-145 compared with the control VSMC groups; all the tested flavonoids increased miR-145 in the 100 nM concentration. Among the test compounds, EGCG showed the strongest augmenting effect on miR-145 and myocardin, however, it also abolished Ang II-induced Klf4. A [3H]-thymidine incorporation proliferation assay demonstrated that EGCG inhibited Ang II-induced VSMC proliferation, and Klf4 siRNA presented with the similar results. Immunohistochemical analysis and confocal microscopy demonstrated increased Klf4 expression and the arterial lumen was narrowed after balloon injury 14 days. With the addition of EGCG (50 mg/kg) and Klf4 siRNA, neointimal formation was reduced by 40.7% and 50.5% compared with balloon injury 14 days; Klf4 expression also was attenuated. This study demonstrated EGCG increased miR-145 and attenuated Klf4, and ameliorated neointimal formation in vitro and in vivo. The novel suppressive effect was mediated through the miR-145 and Klf4/myocardin pathways.

A predictive model for the development of chronic obstructive pulmonary disease.

The screening of a person at risk for chronic obstructive pulmonary disease (COPD) and timely treatment may provide opportunities to delay the progressive destruction of lung function. Therefore, a model to predict the disease is required. We hypothesized that demographic and clinical information in combination with genetic markers would aid in the prediction of COPD development, prior to its onset. The aim of the present study was to create a predictive model for COPD development. Demographic, clinical presentation and genetic polymorphisms were recorded in COPD patients and control subjects. Nighty-six single-nucleotide polymorphisms of 46 genes were selected for genotyping in the case-control study. A predictive model was produced using logistic regression with a stepwise model-building approach and was validated. A total of 331 patients and 351 control subjects were included. The logistic regression identified the following predictors: Gender, respiratory infection in early life, low birth weight, smoking history and genotype polymorphisms (rs2070600, rs10947233, rs1800629, rs2241712 and rs1205). The model was established using the following formula: COPD = 1/[1 + exp (-2.4933-1.2197 gender + 1.1842 respiratory infection in early life + 2.4350 low birth weight + 1.8524 smoking - 1.1978 rs2070600 + 2.0270 rs10947233 + 1.1913 rs10947233 + 0.6468 rs1800629 + 0.5272 rs2241712 + 0.4024 rs1205)] (when the value is >0.5). The Hosmer-Lemeshow test showed no significant deviations between the observed and predicted events. Validation of the model in 50 patients showed a modest sensitivity and specificity. Therefore, a predictive model based on demographic, clinical and genetic information may identify COPD prior to its onset.

Characterization of Somatic Mutations in Air Pollution-Related Lung Cancer.

Air pollution has been classified as Group 1 carcinogenic to humans, but the underlying tumorigenesis remains unclear. In Xuanwei City of Yunnan Province, the lung cancer incidence is among the highest in China attributed to severe air pollution generated by combustion of smoky coal, providing a unique opportunity to dissect lung carcinogenesis of air pollution. Here we analyzed the somatic mutations of 164 non-small cell lung cancers (NSCLCs) from Xuanwei and control regions (CR) where smoky coal was not used. Whole genome sequencing revealed a mean of 289 somatic exonic mutations per tumor and the frequent C:G â†’ A:T nucleotide substitutions in Xuanwei NSCLCs. Exome sequencing of 2010 genes showed that Xuanwei and CR NSCLCs had a mean of 68 and 22 mutated genes per tumor, respectively (p < 0.0001). We found 167 genes (including TP53, RYR2, KRAS, CACNA1E) which had significantly higher mutation frequencies in Xuanwei than CR patients, and mutations in most genes in Xuanwei NSCLCs differed from those in CR cases. The mutation rates of 70 genes (e.g., RYR2, MYH3, GPR144, CACNA1E) were associated with patients' lifetime benzo(a)pyrene exposure. This study uncovers the mutation spectrum of air pollution-related lung cancers, and provides evidence for pollution exposure-genomic mutation relationship at a large scale.

Exome sequencing identifies somatic mutations of DDX3X in natural killer/T-cell lymphoma.

Natural killer/T-cell lymphoma (NKTCL) is a malignant proliferation of CD56(+) and cytoCD3(+) lymphocytes with aggressive clinical course, which is prevalent in Asian and South American populations. The molecular pathogenesis of NKTCL has largely remained elusive. We identified somatic gene mutations in 25 people with NKTCL by whole-exome sequencing and confirmed them in an extended validation group of 80 people by targeted sequencing. Recurrent mutations were most frequently located in the RNA helicase gene DDX3X (21/105 subjects, 20.0%), tumor suppressors (TP53 and MGA), JAK-STAT-pathway molecules (STAT3 and STAT5B) and epigenetic modifiers (MLL2, ARID1A, EP300 and ASXL3). As compared to wild-type protein, DDX3X mutants exhibited decreased RNA-unwinding activity, loss of suppressive effects on cell-cycle progression in NK cells and transcriptional activation of NF-κB and MAPK pathways. Clinically, patients with DDX3X mutations presented a poor prognosis. Our work thus contributes to the understanding of the disease mechanism of NKTCL.

Mimecan, a Hormone Abundantly Expressed in Adipose Tissue, Reduced Food Intake Independently of Leptin Signaling.

Adipokines such as leptin play important roles in the regulation of energy metabolism, particularly in the control of appetite. Here, we describe a hormone, mimecan, which is abundantly expressed in adipose tissue. Mimecan was observed to inhibit food intake and reduce body weight in mice. Intraperitoneal injection of a mimecan-maltose binding protein (-MBP) complex inhibited food intake in C57BL/6J mice, which was attenuated by pretreatment with polyclonal antibody against mimecan. Notably, mimecan-MBP also induced anorexia in A(y)/a and db/db mice. Furthermore, the expression of interleukin (IL)-1ß and IL-6 was up-regulated in the hypothalamus by mimecan-MBP, as well as in N9 microglia cells by recombinant mouse mimecan. Taken together, the results suggest that mimecan is a satiety hormone in adipose tissue, and that mimecan inhibits food intake independently of leptin signaling by inducing IL-1ß and IL-6 expression in the hypothalamus.

Genomic landscape of CD34+ hematopoietic cells in myelodysplastic syndrome and gene mutation profiles as prognostic markers.

Myelodysplastic syndrome (MDS) includes a group of diseases characterized by dysplasia of bone marrow myeloid lineages with ineffective hematopoiesis and frequent evolution to acute myeloid leukemia (AML). Whole-genome sequencing was performed in CD34(+) hematopoietic stem/progenitor cells (HSPCs) from eight cases of refractory anemia with excess blasts (RAEB), the high-risk subtype of MDS. The nucleotide substitution patterns were found similar to those reported in AML, and mutations of 96 protein-coding genes were identified. Clonal architecture analysis revealed the presence of subclones in six of eight cases, whereas mutation detection of CD34(+) versus CD34(-) cells revealed heterogeneity of HSPC expansion status. With 39 marker genes belonging to eight functional categories, mutations were analyzed in 196 MDS cases including mostly RAEB (n = 89) and refractory cytopenia with multilineage dysplasia (RCMD) (n = 95). At least one gene mutation was detected in 91.0% of RAEB, contrary to that in RCMD (55.8%), suggesting a higher mutational burden in the former group. Gene abnormality patterns differed between MDS and AML, with mutations of activated signaling molecules and NPM1 being rare, whereas those of spliceosome more common, in MDS. Finally, gene mutation profiles also bore prognostic value in terms of overall survival and progression free survival.

Genome-wide association study identifies a novel susceptibility gene for serum TSH levels in Chinese populations.

Thyroid-stimulating hormone (TSH) is a sensitive indicator of thyroid function. High and low TSH levels reflect hypothyroidism and hyperthyroidism, respectively. Even within the normal range, small differences in TSH levels, on the order of 0.5-1.0 mU/l, are associated with significant differences in blood pressure, BMI, dyslipidemia, risk of atrial fibrillation and atherosclerosis. Most of the variance in TSH levels is thought to be genetically influenced. We conducted a genome-wide association study of TSH levels in 1346 Chinese Han individuals. In the replication study, we genotyped four candidate SNPs with the top association signals in an independent isolated Chinese She cohort (n = 3235). We identified a novel serum TSH susceptibility locus within XKR4 at 8q12.1 (rs2622590, Pcombined = 2.21 × 10(-10)), and we confirmed two previously reported TSH susceptibility loci near FOXE1 at 9q22.33 and near CAPZB at 1p36.13, respectively. The rs2622590_T allele at XKR4 and the rs925489_C allele near FOXE1 were correlated with low TSH levels and were found to be nominally associated to patients with papillary thyroid carcinoma (PTC) (OR = 1.41, P= 0.014 for rs2622590_T, and OR = 1.61, P= 0.030 for rs925489_C). The rs2622590 and rs925489 genotypes were also correlated with the expression levels of FOXE1 and XKR4, respectively, in PTC tissues (P = 2.41 × 10(-4) and P= 0.02). Our findings suggest that the SNPs in XKR4 and near FOXE1 are involved in the regulation of TSH levels.

Phenotypic and molecular characteristics in eleven Chinese patients with 5α-reductase Type 2 deficiency.

CONTEXT: Steroid 5α-reductase type 2 deficiency (5α-RD2) is a male-limited, autosomal recessive inherited disease. Affected 46, XY individuals usually present with ambiguous genitalia at birth. An early and precise diagnosis is of great value to the long-term prognosis of the disease. OBJECTIVE: To describe the clinical features and molecular determinants in 11 Chinese patients with the SRD5A2 gene mutation and to investigate the functional alteration arising from a novel splicing site mutation identified in one of the patients. SUBJECTS AND METHODS: Eleven subjects born with abnormal external genitalia from 10 unrelated families were recruited. Among them, nine patients who were reared as girls underwent virilization and gender change after puberty. Genotyping analysis of the SRD5A2 gene was performed in each of the patients. Haplotype analysis was performed in five patients with a prevalent mutation of p.G203S to illustrate the founder effect in China. Functional impairment of the new variant was explored by an in vitro splicing study and enzymatic activity assay. RESULTS: Nine mutations in the SRD5A2 gene were detected in the eleven patients. In addition to the previously reported p.G203S, p.R227Q, p.N193S, p.R246Q, p.Q6X, p.A228V, c.655delT and IVS1-2 A>G, a novel splicing site mutation (IVS4 + 2 T>C) was identified. From an in vitro functional study, this mutation was found to result in a skipping of exon 4 in the course of mRNA splicing, leading to a truncated protein of 205 amino acids that lacks the catalysing activity. Two siblings with the same compound heterozygous mutation (IVS1-2A>G/p.G203S) exhibited differing phenotypes and opposite patterns of gender rearing. A prevalent variation p.V89L combined with c.655delT was revealed to cause a mild phenotype of 5α-RD2 with a micropenis. CONCLUSION: This cohort study describes the phenotypic, biochemical and long-term outcome in 11 Chinese patients with 5α-RD2 deficiency and defines the genotypic spectrum of SRD5A2 mutations in China.

The association of SCGB3A2 polymorphisms with the risk of Graves' disease: a meta-analysis.

The aim of this study is to assess the association of the SCGB3A2 -112G>A promoter polymorphism with Graves' disease(GD) using a meta-analysis. Relevant studies were identified using PubMed and EMBASE electronic databases. A meta-analysis of relevant studies was performed. This meta-analysis included four case-control studies, containing 6,913 GD cases (Caucasian 3904, Han 3009) and 7,185 controls(Caucasian 4155, Han 3030). The combined results showed a significant difference in genotype distribution (-112A/G) between GD and control populations (A vs. G P = 1.53 × 10(-7); GG vs. AA+AG P = 6.78 × 10(-9)). Meta-analysis was performed using a fixed-effects model. Under the dominant model (GG/AA + GA), the AA and GA genotypes were significantly associated with GD (pooled OR = 1.24, 95 % CI 1.12-1.37). When the two European studies are combined, the AA and GA genotypes were also significantly associated with GD (pooled OR = 1.29, 95 % CI 1.20-1.39). This meta-analysis suggests that SCGB3A2 polymorphism at positions -112G>A was associated with GD both in Chinese and Caucasian population.

Refined association of TSH receptor susceptibility locus to Graves' disease in the Chinese Han population.

BACKGROUND: Convincing evidence has demonstrated the association of TSH receptor (TSHR) with Graves' disease (GD) in the Chinese Han population. OBJECTIVE: The aim of this study was to identify the causal variants for GD in the region encompassing TSHR by a refining association study. DESIGN AND METHODS: GD patients (1536) and 1516 sex-matched controls were recruited in the first stage, and an additional 3832 GD patients and 3426 sex-matched controls were recruited in the replication stage. Genotyping was performed using Illumina Human660-Quad BeadChips or TaqMan single nucleotide polymorphism (SNP) Genotyping Assays and the Fluidigm EP1 platform. RESULTS: When the results of regression analysis for 74 genotyped SNPs and 922 imputed SNPs in the first-stage cohort were combined, rs179243 and rs3783949 were the probable susceptibility SNPs associated with GD in TSHR. Eleven SNPs, including rs179243 and rs3783949, were selected to further refine the association in the replication study. Finally, rs12101261 and rs179243 were confirmed as independent GD susceptibility variants in the replication and combined populations. Further, we also found that the rate of persistent TSHR autoantibody positivity (pTRAb+) was significantly higher in the GD patients with the susceptible genotypes rs12101261 or rs179243 than in the GD patients carrying the protective genotypes, after the GD patients had been treated for more than 1 year. CONCLUSIONS: These findings indicate that rs12101261 and rs179243 are the possible causal SNPs for GD susceptibility in the TSHR gene and could serve as genetic markers to predict the outcome of pTRAb+ in GD patients.

Replication of association of nine susceptibility loci with Graves' disease in the Chinese Han population.

This study is to evaluate the association of 9 single nucleotide polymorphisms (SNPs) with Graves' disease (GD) in different homogenous samples of the Chinese Han population. A total of 2,865 unrelated individuals were enrolled from Linyi City, Shandong Province, China, including 1,139 patients of GD and 1,726 controls. All 9 SNPs showed significant associations with GD (P < 1.3×10(-4), Bonferroni corrected Pc < 0.001). The most significant association was detected at rs2281388 at the HLA-DPB1 locus (P=1.3×10(-21); OR=1.62, 95% CI: 1.47-1.79). After adjusting for gender and age, 7 SNPs remained significantly associated with GD (P < 3.4×10(-4), Pc < 0.003). The risk of GD caused by any of these SNPs was not significantly different between female and male participants (Phet > 0.15). Four SNPs located in MHC regions were significantly associated with GD in different ages (P < 8.4×10(-4), Pc < 0.04). The risks of any SNP leading to the development of GD did not differ significantly in different ages (P_trend > 0.02, Pc > 0.18). The rs6457617 at the HLA-DR-DQ locus was significantly correlated with gender in GD patients (P=0.004, Pc =0.04). No significant correlation was found between any SNP and age of diagnosis in GD patients (P > 0.02, Pc > 0.17). The 9 previously identified SNPs are associated with GD in the Chinese Han population. And, gender and age may not influence the associations between the 9 SNPs and GD.

Identification of BACH2 as a susceptibility gene for Graves' disease in the Chinese Han population based on a three-stage genome-wide association study.

The BACH2 gene regulates B cell differentiation and function and has been reported to be a shared susceptibility gene for several autoimmune diseases. Our previous genome-wide association study (GWAS) indicated that several single nucleotide polymorphisms (SNPs) in the BACH2 gene are associated with Graves' disease (GD) in the Chinese Han population; however, the association did not achieve genome-wide significance levels. Recently, this association of BACH2 with GD was confirmed in Caucasians in the UK population, but fine mapping in this region has not yet been reported. Here, we provide a refined analysis of a 331-kb region in the BACH2 gene, which harbors 359 SNPs, using GWAS data from 1,442 GD patients and 1,468 controls. The SNPs rs2474619 and rs9344996 were implied as the independent variants associated with GD by forward and two-locus logistic regression analysis. We genotyped eight out of 10 tagSNPs with P < 1 × 10(-3) in 3,508 GD patients and 3,209 controls, the results also showed that rs2474619 was independently associated with GD in the combined population from GWAS and the second stage (P = 1.81 × 10(-5)). The rs2474619 and rs9344996 were further genotyped in the third stage cohorts, and rs2474619 showed evidence of association with GD at genome-wide significance levels in the combined population (P = 3.28 × 10(-8), odds ratio = 1.13). The association of rs9344996 with GD can be explained by its linkage to rs2474619 in the combined population. Our study clearly demonstrated that BACH2 is a susceptibility gene for GD in the Chinese Han population and further supported rs2474619, in intron 2 of BACH2, is the best association signal with GD. However, the mechanism by which BACH2 confers increased risk of GD requires further study.

Association between the interleukin-13 gene and development of chronic obstructive pulmonary disease in southern Chinese Han population: a case-control study.

BACKGROUND: Interleukin-13 (IL-13) has been implicated to be responsible for recruitment of inflammatory cells from the blood to the lung, regulation of matrix metalloproteinase and induction of mucin production and secretion in chronic obstructive pulmonary disease (COPD). We determined plasma IL-13 levels in patients with COPD and investigated its association with common polymorphisms of IL-13 gene in a case-control study. METHODS: We genotyped 160 cases and 175 control subjects in a local hospital using Mass-Array(TM) Technology Platform then tested the association of four SNPs in IL-13 (rs1295685, rs1800925, rs1881457, rs20541) with COPD, and then determined plasma IL-13 levels in patients with COPD and controls. RESULTS: Association was found between IL-13 gene SNPs (rs20541 and rs1800925) and an increased risk of COPD. By linkage disequilibrium (LD) analysis, two blocks (rs1881457 and rs1800925; rs20541 and rs1295685) were found. The risk of COPD was found associated with the IL-13 gene polymorphism among southern Chinese Han population. Plasma IL-13 level was increased in COPD patients compared with controls. CONCLUSIONS: The polymorphism of the IL-13 gene is associated with an increased risk of COPD in southern Chinese Han population. Plasma IL-13 levels were found elevated in patients with COPD.