Allelic diversity in the TGFB1 regulatory region: characterization of novel functional single nucleotide polymorphisms

The rs1800469 T/T and rs1800470 C/C genotypes of the TGFB1 gene confer protection against diabetic retinopathy in a Southern Brazilian population

The transforming growth factor beta 1 (TGFB1) is a pro-inflammatory cytokine that plays a key role in the mechanisms of angiogenesis and breakdown of the blood-retina barrier, which are implicated in the pathogenesis of diabetic retinopathy (DR). Polymorphisms in the TGFB1 gene have been associated with DR; however, results are still contradictory. Therefore, the aim of this study was to investigate the potential association between two TGFB1 polymorphisms and DR. This study included 992 patients with diabetes mellitus (DM): 546 patients with DR (cases) and 446 patients without DR and with ≥10 years of DM (controls). The TGFB1 rs1800469 and rs1800470 polymorphisms were genotyped by real-time PCR. Frequency of rs1800469 T/T genotype was higher in controls compared to DR cases (18.3% vs. 12.7%, P= 0.022). This genotype remained associated with protection for DR, adjusting for covariables (OR= 0.604; 95% CI 0.395 - 0.923; P= 0.020, recessive model). The rs1800470 C/C genotype was observed in 25.4% of the controls and 18.0% of the cases (P= 0.015); thus, being associated with protection against DR under the recessive model (OR= 0.589; 95% CI 0.405 - 0.857; P= 0.006), adjusting for covariables. In conclusion, the TGFB1 rs1800469 and rs1800470 polymorphisms are associated with protection against DR in DM patients from Southern Brazil.

Advanced statistics identification of participant and treatment predictors associated with severe adverse effects induced by fluoropyrimidine-based chemotherapy

PURPOSE

Adverse effects following fluoropyrimidine-based chemotherapy regimens are common. However, there are no current accepted diagnostic markers for prediction prior to treatment, and the underlying mechanisms remain unclear. This study aimed to determine genetic and non-genetic predictors of adverse effects.

METHODS

Genomic DNA was analyzed for 25 single nucleotide polymorphisms (SNPs). Demographics, comorbidities, cancer and fluoropyrimidine-based chemotherapy regimen types, and adverse effect data were obtained from clinical records for 155 Australian White participants. Associations were determined by bivariate analysis, logistic regression modeling and Bayesian network analysis.

RESULTS

Twelve different adverse effects were observed in the participants, the most common severe adverse effect was diarrhea (12.9%). Bivariate analysis revealed associations between all adverse effects except neutropenia, between genetic and non-genetic predictors, and between 8 genetic and 12 non-genetic predictors with more than 1 adverse effect. Logistic regression modeling of adverse effects revealed a greater/sole role for six genetic predictors in overall gastrointestinal toxicity, nausea and/or vomiting, constipation, and neutropenia, and for nine non-genetic predictors in diarrhea, mucositis, neuropathy, generalized pain, hand-foot syndrome, skin toxicity, cardiotoxicity and fatigue. The Bayesian network analysis revealed less directly associated predictors (one genetic and six non-genetic) with adverse effects and confirmed associations between six adverse effects, eight genetic predictors and nine non-genetic predictors.

CONCLUSION

This study is the first to link both genetic and non-genetic predictors with adverse effects following fluoropyrimidine-based chemotherapy. Collectively, we report a wealth of information that warrants further investigation to elucidate the clinical significance, especially associations with genetic predictors and adverse effects.

Targeted Demethylation of the TGFβ1 mRNA Promotes Myoblast Proliferation via Activating the SMAD2 Signaling Pathway

Recent evidence suggested that N6-methyladenosine (m6A) methylation can determine m6A-modified mRNA fate and play an important role in skeletal muscle development. It was well known that transforming growth factor beta 1 (TGFβ1) is involved in a variety of cellular processes, such as proliferation, differentiation, and apoptosis. However, little is known about the m6A-mediated TGFβ1 regulation in myogenesis. Here, we observed an increase in endogenous TGFβ1 expression and activity during myotube differentiation. However, the knockdown of TGFβ1 inhibits the proliferation and induces cell apoptosis of myoblast. Moreover, we found that m6A in 5′-untranslated regions (5′UTR) of TGFβ1 promote its decay and inhibit its expression, leading to the blockage of the TGFβ1/SMAD2 signaling pathway. Furthermore, the targeted specific demethylation of TGFβ1 m6A using dCas13b-FTO significantly increased the TGFβ1-mediated activity of the SMAD2 signaling pathway, promoting myoblast proliferation. These findings suggest that TGFβ1 is an essential regulator of myoblast growth that is negatively regulated by m6A. Overall, these results highlight the critical role of m6A-mediated post-transcriptional regulation in myogenesis.

Cytokine TGFβ Gene Polymorphism in Asthma: TGF-Related SNP Analysis Enhances the Prediction of Disease Diagnosis (A Case-Control Study With Multivariable Data-Mining Model Development)

Introduction

TGF-β and its receptors play a crucial role in asthma pathogenesis and bronchial remodeling in the course of the disease. TGF-β1, TGF-β2, and TGF-β3 isoforms are responsible for chronic inflammation, bronchial hyperreactivity, myofibroblast activation, fibrosis, bronchial remodeling, and change the expression of approximately 1000 genes in asthma. TGF-β SNPs are associated with the elevated plasma level of TGF-β1, an increased level of total IgE, and an increased risk of remodeling of bronchi.

Methods

The analysis of selected TGF-β1, TGF-β2, TGF-β3-related single-nucleotide polymorphisms (SNP) was conducted on 652 DNA samples with an application of the MassARRAY® using the mass spectrometry (MALDI-TOF MS). Dataset was randomly split into training (80%) and validation sets (20%). For both asthma diagnosis and severity prediction, the C5.0 modelling with hyperparameter optimization was conducted on: clinical and SNP data (Clinical+TGF), only clinical (OnlyClinical) and minimum redundancy feature selection set (MRMR). Area under ROC (AUCROC) curves were compared using DeLong’s test.

Results

Minor allele carriers (MACs) in SNP rs2009112 [OR=1.85 (95%CI:1.11-3.1), p=0.016], rs2796821 [OR=1.72 (95%CI:1.1-2.69), p=0.017] and rs2796822 [OR=1.71 (95%CI:1.07-2.71), p=0.022] demonstrated an increased odds of severe asthma. Clinical+TGF model presented better diagnostic potential than OnlyClinical model in both training (p=0.0009) and validation (AUCROC=0.87 vs. 0.80,p=0.0052). At the same time, the MRMR model was not worse than the Clinical+TGF model (p=0.3607 on the training set, p=0.1590 on the validation set), while it was better in comparison with the Only Clinical model (p=0.0010 on the training set, p=0.0235 on validation set, AUCROC=0.85 vs. 0.87). On validation set Clinical+TGF model allowed for asthma diagnosis prediction with 88.4% sensitivity and 73.8% specificity.

Discussion

Derived predictive models suggest the analysis of selected SNPs in TGF-β genes in combination with clinical factors could predict asthma diagnosis with high sensitivity and specificity, however, the benefit of SNP analysis in severity prediction was not shown.

miR-2337 induces TGF-β1 production in granulosa cells by acting as an endogenous small activating RNA

Transforming growth factor-β1 (TGF-β1) is essential for ovarian function and female fertility in mammals. Herein, we identified three completely linked variants, including two known variants referred to as c.1583A > G and c.1587A > G and the novel variant c.2074A > C in the porcine TGF-β1 3′-UTR. An important role of these variants in Yorkshire sow fertility was revealed. Variants c.1583A > G and c.1587A > G were located at the miRNA response element (MRE) of miR-2337 and affected miR-2337 regulation of TGF-β1 3′-UTR activity. Interestingly, miR-2337 induces, not reduces the transcription and production of TGF-β1 in granulosa cells (GCs). Mechanistically, miR-2337 enhances TGF-β1 promoter activity via the MRE motif in the core promoter region and alters histone modifications, including H3K4me2, H3K4me3, H3K9me2, and H3K9ac. In addition, miR-2337 controls TGF-β1-mediated activity of the TGF-β signaling pathway and GC apoptosis. Taken together, our findings identify miR-2337 as an endogenous small activating RNA (saRNA) of TGF-β1 in GCs, while miR-2337 is identified as a small activator of the TGF-β signaling pathway which is expected to be a new target for rescuing GC apoptosis and treating low fertility.

TGFB1 +869 T > C (rs1800470) variant is independently associated with susceptibility, laboratory activity, and TGF-β1 in patients with systemic lupus erythematosus

The aim of this study was to evaluate the association of the +869 T > C (rs1800470) and -509 C > T (rs1800469) TGFB1 variants, individually or in haplotypes structure, with susceptibility, autoantibodies, disease activity, and TGF-β1 plasma levels in patients with systemic lupus erythematosus (SLE). The study included 203 patients with SLE and 165 healthy controls. TGFB1 variants were determined by real-time polymerase chain reaction (qPCR). Plasma levels of TGF-β1 were determined using immunofluorimetric assay. The TGFB1 + 869 CC genotype was associated with SLE susceptibility (OR: 1.710, 95%CI: 1.020-2.866, p = 0.042) and with reduction of C4 (p = 0.040) and TGF-β1 levels (p = 0.044). In addition, patients with TGFB1 + 869 TC and CC genotypes and positive anti-dsDNA had lower TGF-β1 levels than those with TT (p = 0.004). TGFB1 -509 TT genotype was associated with reduced levels of C4 (p = 0.032). There was no association between haplotypes and clinical and laboratory parameters. Our data demonstrated that the TGFB1 + 869 T > C variant could be used as a genetic marker for SLE susceptibility and both variants as predictors of laboratory activity. This is the first study to demonstrate that TGF-β1 levels could be modulated by the interaction between TGFB1 + 869 C allele, in homozygosity, or heterozygosity, and the presence of anti-dsDNA.

TGFB1 (rs1800470 and rs1800469) variants are independently associated with disease activity and autoantibodies in rheumatoid arthritis patients

To evaluate the association between TGFB1 + 869 T > C (rs1800470) and TGFB1-509 C > T (rs1800469) variants with susceptibility for rheumatoid arthritis (RA), disease activity, presence of rheumatoid factor (RF), anti-cyclic citrullinated peptide (anti-CCP) and TGF-β1 plasma levels. A total of 262 patients with RA and 168 control individuals were tested for the TGFB1 variants using a TaqMan genotyping assay. Disease activity score in 28 joints (DAS28) classified RA patients into two groups of disease activity: remission/mild (DAS28 < 3.2) and moderate/severe (DAS28 ≥ 3.2). TGFB1 + 869 T > C and -509 C > T variants, independently or in haplotype combination, were not associated with RA's susceptibility. Patients with the TGFB1-509 TT genotype had a higher frequency of DAS28 ≥ 3.2 (OR 2.58, 95% CI 1.04-6.42, p = 0.041). The TGFB1 + 869 CC genotype in seropositive patients for RF or anti-CCP was associated with decreased TGF-β1 levels (p = 0.032 and p = 0.039, respectively). Patients with the TGFB1 + 869 C allele and elevated RF titles demonstrated a higher frequency of DAS28 ≥ 3.2 (p = 0.037). The TGFB1 + 869 T > C variant was associated with diminished TGF-β1 plasma levels and moderate/severe activity disease only in seropositive RF patients. This is the first study showing that TGF-β1 plasma levels can be modulated by the interaction between the TGFB1 + 869 T > C variant and autoantibodies. However, the TGFB1-509 C > T variant was associated with moderate/severe activity disease, independently of autoantibodies positivity. Thus, our findings suggest that TGFB1 + 869 T > C and -509 C > T variants can predict activity disease in different RA patient subgroups.

Innate Immune and Neuronal Genetic Markers are Highly Predictive of Postoperative Pain and Morphine Patient-Controlled Analgesia requirements in Indian but not Chinese or Malay hysterectomy patients

OBJECTIVE

Pain severity and opioid requirements in the postoperative period show substantial and clinically significant inter-patient variation due mainly to factors such as age, surgery type and duration. Genetic factors have not been adequately assessed except for the neuronal OPRM1 rs1799971 and COMT rs4680, whereas the contribution of innate immune signalling pathway genetics was seldom investigated.

SETTING

Hospital surgical ward.

SUBJECTS

107 Indian, 184 Malay and 750 Han Chinese women undergoing total hysterectomy surgery.

METHODS

Morphine consumption, pre- and post-operative pain were evaluated in relation to genetic variability comprising 19 SNPs in 14 genes involved in glial activation, inflammatory signalling and neuronal regulation plus OPRM1 (1 SNP) and COMT (3 SNPs).

RESULTS

Pre- and post-operative pain and age were associated with increased and decreased morphine consumption, respectively. In Chinese patients, only 8% of the variability in consumption could be explained by these nongenetic and genetic (BDNF, IL1B, IL6R, CRP, OPRM1, COMT, MYD88) factors. However, in Indian patients, 41% of morphine consumption variability could be explained by age (explaining <3%) and variants in OPRM1 rs1799971, CRP rs2794521, TLR4 rs4986790, IL2 rs2069762, COMT rs4818, TGFB1 rs1800469 and IL6R rs8192284 when not controlling for postoperative pain.

CONCLUSIONS

This is the highest known value reported for genetic contributions (38%) to morphine use in the acute postoperative pain setting. Our findings highlight the need to incorporate both genetic and non-genetic factors and, consider ethnicity-dependent and non-additive genotypic models, when assessing factors that contribute to variability in opioid use.

Genetic and Epigenetic Fine-Tuning of TGFB1 Expression Within the Human Osteoarthritic Joint

OBJECTIVE

Osteoarthritis (OA) is an age-related disease characterized by articular cartilage degeneration. It is largely heritable, and genetic screening has identified single-nucleotide polymorphisms (SNPs) marking genomic risk loci. One such locus is marked by the G>A SNP rs75621460, downstream of TGFB1. This gene encodes transforming growth factor β1, the correct expression of which is essential for cartilage maintenance. This study investigated the regulatory activity of rs75621460 to characterize its impact on TGFB1 expression in disease-relevant patient samples (n = 319) and in Tc28a2 immortalized chondrocytes.

METHODS

Articular cartilage samples from human patients were genotyped, and DNA methylation levels were quantified using pyrosequencing. Gene reporter and electrophoretic mobility shift assays were used to determine differential nuclear protein binding to the region. The functional impact of DNA methylation on TGFB1 expression was tested using targeted epigenome editing.

RESULTS

The analyses showed that SNP rs75621460 was located within a TGFB1 enhancer region, and the OA risk allele A altered transcription factor binding, with decreased enhancer activity. Protein complexes binding to A (but not G) induced DNA methylation at flanking CG dinucleotides. Strong correlations between patient DNA methylation levels and TGFB1 expression were observed, with directly opposing effects in the cartilage and the synovium at this locus. This demonstrated biologic pleiotropy in the impact of the SNP within different tissues of the articulating joint.

CONCLUSION

The OA risk SNP rs75621460 impacts TGFB1 expression by modulating the function of a gene enhancer. We propose a mechanism by which the SNP impacts enhancer function, providing novel biologic insight into one mechanism of OA genetic risk, which may facilitate the development of future pharmacologic therapies.

Novel association between TGFA, TGFB1, IRF1, PTGS2 and IKBKB single-nucleotide polymorphisms and occurrence, severity and treatment response of major depressive disorder

Background

Activation of the immune system might affect the severity of depressive episodes as well as response to the antidepressant treatment. The purpose of this study was to investigate whether the occurrence of variant alleles of analyzed SNPs are involved in prevalence and progression of depression. Moreover, selected genes and SNPs have not been investigated in context of the disease severity and treatment. Therefore, six polymorphisms were selected: g.41354391A>G-TGFB1 (rs1800469), g.132484229C>A-IRF (rs2070729), g.186643058A>G-PTGS2 (rs5275), g.186640617C>T-PTGS2 (rs4648308), g.70677994G>A-TGFA (rs2166975) and g.42140549G>T-IKBKB (rs5029748).

Methods

A total of 360 (180 patients and 180 controls) DNA samples were genotyped using TaqMan probes.

Results

We observed that A/G of the rs2166975 TGFA, A/C of rs2070729 IRF1 and G/T of rs5029748 IKBKB were associated with an increased risk of depression development while the T/T of rs5029748 IKBKB, T/T of rs4648308 PTGS2 and G/G of rs2166975 TGFA reduced this risk. We also stratified the study group according to gender and found that genotype A/G and allele G of the rs2166975 TGFA, G/T of rs5029748 IKBKB as well as C allele of rs4648308 PTGS2, homozygote A/A and allele A of rs5275 PTGS2 were associated with increased risk of depression development in men while homozygote G/G of rs5275 PTGS2 decreased this risk. Moreover, C/T of rs4648308 PTGS2 and A/G of rs5275 PTGS2 was positively correlated with the risk of the disease occurrence in women. Furthermore, a gene-gene analysis revealed a link between studied polymorphisms and depression. In addition, A/A of rs1800469 TGFB1 was associated with earlier age of onset of the disease while G/G of this SNP increased severity of the depressive episode. Interestingly, A/C of rs2070729 IRF1 and T/T of rs5029748 IKBKB may modulate the effectiveness of selective serotonin reuptake inhibitors therapy. In conclusion, studied SNPs may modulate the risk of occurrence, age of onset, severity of the disease and response to the antidepressant treatment.

The correlation of TGFβ1 gene polymorphisms with congenital heart disease susceptibility

OBJECTIVE

The aim of this study was to investigate the relationship between single nucleotide polymorphisms (SNPs) in transforming growth factor beta 1 (TGFβ1) gene (rs1982073 and rs1800471) and congenital heart disease (CHD) susceptibility.

METHODS

Totally, 145 CHD patients and 140 healthy controls were enrolled in this case-control study. The case and control groups were matched in age and gender. Genotyping for TGFβ1 gene SNPs rs1982073 and rs1800471 was conducted via polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) approach. Chi-square test was used to analyze the association of TGFβ1 polymorphisms with CHD risk. The results were presented as odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

The frequencies of the CT genotype and T allele of TGFβ1 gene SNP rs1982073 were significantly different between cases and controls (P < 0.05), revealing their associations with reduced susceptibility to CHD (OR = 0.521, 95%CI = 0.302-0.897; OR = 0.706, 95%CI = 0.507-0.983). Nevertheless, TGFβ1 gene SNP rs1800471 had no significant association with CHD susceptibility (P > 0.05).

CONCLUSION

TGFβ1 gene SNP rs1982073 might be correlated with CHD susceptibility, and the T allele might decrease the disease risk. However, TGFβ1 gene polymorphism rs1800471 was not related to CHD risk.

Polymorphisms in the TGFB1 signal peptide influence human papillomavirus infection and development of cervical lesions

The main purpose was to assess the effect of c.29C>T and c.74G>C polymorphisms in the TGFB1 signal peptide on HPV infection and development of cervical lesions. Cervical swabs and blood samples were obtained from 349 outpatient women, along with socio-demographic and sexual behavioral data. The study population was stratified by absence or presence of HPV DNA, as tested by PCR, as well as by lesion grade. TGFB1 signal peptide polymorphisms were genotyped using PCR-restriction fragment length polymorphism. HPV DNA was detected in 172 (49.3%) patients. c.74GC and the combined c.29CC+CT/c.74GC genotype were more frequent in infected patients (35.1 and 15.7%) than in uninfected women (6.2 and 14.7%). Accordingly, these genotypes were associated with a higher risk of HPV infection, with odds ratio and 95% confidence interval of 2.81 and 1.35-5.86 (P = 0.004) for c.74GC and 3.14 and 1.42-6.94 (P = 0.004) for the combined genotype, respectively. High-grade lesions were also 2.48 times more likely to occur in c.29CC patients than in c.29TT patients, with a 95% confidence interval of 1.01-6.08 (P = 0.047). The data demonstrate that c.74G>C and c.29C>T polymorphisms are significantly associated with risk of HPV infection and high-grade squamous intraepithelial lesions, respectively. Thus, TGFB1 signal peptide polymorphisms are potential susceptibility markers.

Association Between TGF-β1 Polymorphisms and Asthma Susceptibility Among the Chinese: A Meta-Analysis

OBJECTIVE

Asthma is the most common chronic pulmonary disease in China and is characterized by airway inflammation and episodic airflow obstruction. The aim of this meta-analysis was to evaluate the relation of two transforming growth factor-β1 (TGF-β1) polymorphisms with asthma risk in Chinese population.

METHODS

PubMed, Springer, EMBASE, MEDLINE, CNKI (China National Knowledge Infrastructure), and Wanfang databases were used to search and retrieve relevant eligible case-control studies published through December 2017. The odds ratios (OR) and 95% confidence intervals (CI) were used to evaluate the effect.

RESULTS

A total of 2040 asthma patients and 1952 controls from 12 studies were analyzed. Two polymorphic sites of TGF-β1 gene were identified: -509C/T and +869T/C. We found that the -509C/T polymorphism was associated with increased asthma risk under the heterozygous model (CT vs. CC: OR = 1.40, 95% CI = 1.03-1.90, p = 0.03) and the dominant model (TT+CT vs. CC: OR = 1.41, 95% CI = 1.05-1.90, p = 0.02). Subgroup analyses by age suggested that -509C/T variant was associated with childhood asthma. Analysis of disease severity indicated that this variant was associated with both mild-to-moderate asthma and severe asthma. However, the +869T/C polymorphism was not associated with asthma susceptibility in subgroup analysis by age or disease severity.

CONCLUSIONS

This study demonstrated that the -509C/T polymorphism of the TGF-β1 gene might be a risk factor for asthma in the Chinese population, especially in Chinese children. Further large-scale case-control studies are still required.

Butyrate produced by gut commensal bacteria activates TGF-beta1 expression through the transcription factor SP1 in human intestinal epithelial cells

The intestinal microbiota contributes to the global wellbeing of their host by their fundamental role in the induction and maintenance of a healthy immune system. Commensal bacteria shape the mucosal immune system by influencing the proportion and the activation state of anti-inflammatory regulatory T cells (Treg) by metabolites that are still only partially unravelled. Microbiota members such as Clostridiales provide a transforming growth factor β (TGFβ)-rich environment that promotes the accumulation of Treg cells in the gut. The intestinal epithelial cells (IECs) take a central part in this process, as they are a major source of TGFβ1 upon bacterial colonisation. In this study, we investigated which gut commensal bacteria were able to regulate the TGFB1 human promoter in IECs using supernatants from cultured bacteria. We reported that Firmicutes and Fusobacteria supernatants were the most potent TGFB1 modulators in HT-29 cells. Furthermore, we demonstrated that butyrate was the main metabolite in bacterial supernatants accounting for TGFβ1 increase. This butyrate-driven effect was independent of the G-protein coupled receptors GPR41, GPR43 and GPR109a, the transporter MCT1 as well as the transcription factors NF-κB and AP-1 present on TGFB1 promoter. Interestingly, HDAC inhibitors were inducing a similar TGFB1 increase suggesting that butyrate acted through its HDAC inhibitor properties. Finally, our results showed that SP1 was the main transcription factor mediating the HDAC inhibitor effect of butyrate on TGFB1 expression. This is, to our knowledge, the first characterisation of the mechanisms underlying TGFB1 regulation in IEC by commensal bacteria derived butyrate.

Lack of Association Between TGF-β1 and MDR1 Genetic Polymorphisms and Cyclosporine-Induced Gingival Overgrowth in Kidney Transplant Recipients: A Meta-analysis

BACKGROUND

Gingival overgrowth (GO) induced by cyclosporine (CsA), one of the common complications after kidney transplantation, is associated with a genetic component. However, the effect of TGF-β1 and MDR1 gene polymorphisms on the pathogenesis of CsA-induced GO remains to be determined. This study aimed to determine the association between TGF-β1 and MDR1 gene polymorphisms and CsA-induced GO in kidney transplant recipients.

METHODS

The Pubmed, Embase, Cochrane Library, and Chinese CNKI (China National Knowledge Infrastructure) and Wanfang databases were comprehensively searched. Data were extracted and pooled results estimated from odds ratios (ORs) and 95% confidence intervals (CIs). In addition, quality assessment and publication bias of each eligible study were examined.

RESULTS

Three trials focusing on the relationship between TGF-β1 +869T>C and +915G>C and 3 studies on MDR1 C3435T gene polymorphisms and the onset of CsA-induced GO were included. No association between the +869T>C polymorphism and CsA-induced GO was found in the dominant model (TT+TC vs CC: OR, 0.77; 95% CI, 0.29-2.10; P = .614). In the recessive model, no association was found between the +915G>C polymorphism and CsA-induced GO (CC vs GG+GC: OR, 1.40; 95% CI, 0.81-2.43; P = .225). And in the dominant model, no significance was calculated between MDR1 C3435T gene polymorphisms and CsA-induced GO in kidney transplant recipients (TT vs CC+CT: OR, 1.14; 95% CI, 0.62-2.09; P = .68).

CONCLUSIONS

No significant association exists between TGF-β1 +869T>C, and +915G>C and MDR1 C3435T gene polymorphisms and the pathogenesis of CsA-induced GO in kidney transplant recipients.

The functionality of African-specific variants in the TGFB1 regulatory region and their potential role in HIVAN

BACKGROUND

Transcription of transforming growth factor beta-1 (TGF-β1) is regulated by a polymorphic promoter region containing African-specific single nucleotide polymorphisms (SNPs). Some of these SNPs have higher frequencies among Southern Africans compared to other African populations and their functionality has only been partially studied. Due to the high prevalence of HIV-associated nephropathy (HIVAN) in Africans we hypothesized that functional African TGFB1-promoter SNPs may contribute to HIVAN pathogenesis.

METHODS

The functionality of the TGFB1 -1347 C>T variant and African-specific variants (-1287 G>A, -1154 C>T, -387 C>T and -14 G>A) were examined by measuring reporter gene expression in kidney and fibroblast cell lines co-transfected with TGFB1-promoter constructs and an HIV-Tat expression vector. TGF-β1 immunohistochemical staining was performed on kidney biopsies with HIVAN (n = 18) and compared to control biopsies without HIVAN or tubulointerstitial disease (n = 12) using semi-quantitative and digital image analysis. HIVAN cases were genotyped for TGFB1 -1347 and -387 SNP variants.

RESULTS

TGFB1-promoter haplotypes containing the African -387 T-allele resulted in ~ five-fold repression of TGFB1-promoter activity compared to -387 C haplotypes (p ≤ 0.024). HIV-Tat upregulated TGFB1-promoter activity for haplotypes containing -1347 T and -387 T in transfected renal cells (≈ 1.6-fold; p ≤ 0.030) and fibroblasts (≈ 1.3-fold; p ≤ 0.016). The renal interstitium from HIVAN biopsies, compared to HIV-positive and -negative controls, differed in the semi-quantitative TGF-β1 staining and digital optical density analyses. The TGFB1 -1347 and -387 genotypes in HIVAN cases were similar to population controls.

CONCLUSION

African-specific haplotypes lower TGFB1-promoter activity and expression levels and HIV-Tat upregulates TGFB1 promoter activity irrespective of the haplotype.

Ethnicity-dependent influence of innate immune genetic markers on morphine PCA requirements and adverse effects in postoperative pain

Although several genetic factors have been associated with postsurgical morphine requirements, those involving the innate immune system and cytokines have not been well investigated. The aim of this study was to investigate the contribution of genetic variability in innate immune signalling pathways to variability in morphine dosage after elective caesarean section under spinal anaesthesia in 133 Indian, 230 Malay, and 598 Han Chinese women previously studied. Twenty single nucleotide polymorphisms in 14 genes involved in glial activation (TLR2, TLR4, MYD88, MD2), inflammatory signalling (IL2, IL6, IL10, IL1B, IL6R, TNFA, TGFB1, CRP, CASP1), and neuronal regulation (BDNF) were newly investigated, in addition to OPRM1, COMT, and ABCB1 genetic variability identified previously. Postsurgical patient-controlled analgesia morphine use (mg/24 hours) was binned into 6 normally distributed groups and scored 0 to 5 to facilitate step-down multiple linear regression analysis of genetic predictors, controlling for ethnicity and nongenetic variables. Ethnicity, OPRM1 rs1799971 (increased), TLR2 rs3804100 (decreased), and an interaction between ethnicity and IL1B rs1143634 (increased), predicted 9.8% of variability in morphine use scores in the entire cohort. In the Indian cohort, 14.5% of the variance in morphine use score was explained by IL1B rs1143634 (increased) and TGFB1 rs1800469 (decreased). In Chinese patients, the incidence of postsurgical pain was significantly higher in variant COMT rs4680 genotypes (P = 0.0007) but not in the Malay or Indian cohorts. Innate immune genetics may contribute to variability in postsurgical opioid requirements in an ethnicity-dependent manner.

Transforming growth factor-β1 (C509T, G800A, and T869C) gene polymorphisms and risk of ischemic stroke in North Indian population: A hospital-based case-control study

Background:

Transforming growth factor-beta 1 (TGF-β1) is a multifunctional pleiotropic cytokine involved in inflammation and pathogenesis of cerebrovascular diseases. There is limited information on the association between variations within the TGF-β1 gene polymorphisms and risk of ischemic stroke (IS). The aim of this study was to investigate the association of the TGF-β1 gene (C509T, G800A, and T869C) polymorphisms, and their haplotypes with the risk of IS in North Indian population.

Methods:

A total of 250 IS patients and 250 age- and sex-matched controls were studied. IS was classified using the Trial of Org 10172 in Acute Stroke Treatment classification. Conditional logistic regression analysis was used to calculate the strength of association between TGF-β1 gene polymorphisms and risk of IS. Genotyping was performed using SNaPshot method.

Results:

Hypertension, diabetes, dyslipidemia, alcohol, smoking, family history of stroke, sedentary lifestyle, and low socioeconomic status were found to be associated with the risk of IS. The distribution of C509T, G800A and T869C genotypes was consistent with Hardy-Weinberg Equilibrium in the IS and control groups. Adjusted conditional logistic regression analysis showed a significant association of TGF-β1 C509T (odds ratio [OR], 2.1; 95% CI; 1.2–3.8; P = 0.006), G800A (OR, 4.4; 95% CI; 2.1–9.3; P < 0.001) and T869C (OR, 2.6; 95% CI; 1.5–4.5; P = 0.001) with the risk of IS under dominant model. Haplotype analysis showed that C509-A800-T869 and T509-G800-C869 haplotypes were significantly associated with the increased risk of IS. C509T and T869C were in strong linkage disequilibrium (D' =0.51, r² = 0.23).

Conclusion:

Our results suggest that TGF-β1 polymorphisms and their haplotypes are significantly associated with the risk of IS in North Indian population.

Otosclerosis Associated with a De Novo Mutation -832G > A in the TGFB1 Gene Promoter Causing a Decreased Expression Level

Otosclerosis (OTSC) is defined by abnormal bone remodeling in the otic capsule of middle ear which leads to conductive hearing loss. In our previous study, we have identified a de novo heterozygous mutation -832G > A in the promoter of TGFB1 in an otosclerosis patient. In the present study, we progressively screened this mutation in a cohort of 254 cases and 262 controls. The family members of the patient positive for -832G > A variation were also screened and found inheritance of this variation only to her daughter. Interestingly, this variation is associated with a decreased level of the TGFB1 transcript in the patient compared to her parents and controls. In silico analysis of this mutation predicted the altered binding of two transcription factors v-Myb and MZF1 in the mutated promoter sequence. Further, functional analysis of this mutation using in vitro luciferase and electrophoretic mobility shift assays revealed that this variation is associated with decreased gene expression. In conclusion, this study established the fact that TGFB1 mutation -832G > A altered the TGFB1 promoter activity, which could affect the susceptibility to otosclerosis development. Further, systemic analysis of TGFB1 gene sequence and expression analysis of this gene might reveal its precise role in the pathogenesis of otosclerosis.

Transforming Growth Factor-β1 T869C Gene Polymorphism Is Associated with Acquired Sick Sinus Syndrome via Linking a Higher Serum Protein Level

Background

Familial sick sinus syndrome is associated with gene mutations and dysfunction of ion channels. In contrast, degenerative fibrosis of the sinus node tissue plays an important role in the pathogenesis of acquired sick sinus syndrome. There is a close relationship between transforming growth factor-β1 mediated cardiac fibrosis and acquired arrhythmia. It is of interest to examine whether transforming growth factor-β1 is involved in the pathogenesis of acquired sick sinus syndrome.

Methods

Overall, 110 patients with acquired SSS and 137 age/gender-matched controls were screened for transforming growth factor-β1 and cardiac sodium channel gene polymorphisms using gene sequencing or restriction fragment length polymorphism methods. An enzyme-linked immunosorbent assay was used to determine the serum level of transforming growth factor-β1.

Results

Two transforming growth factor-β1 gene polymorphisms (C-509T and T+869C) and one cardiac sodium channel gene polymorphism (H588R) have been identified. The C-dominant CC/CT genotype frequency of T869C was significantly higher in acquired sick sinus syndrome patients than in controls (OR 2.09, 95% CI 1.16–3.75, P = 0.01). Consistently, the level of serum transforming growth factor-β1 was also significantly greater in acquired sick sinus syndrome group than in controls (5.3±3.4 ng/ml vs. 3.7±2.4 ng/ml, P = 0.01). In addition, the CC/CT genotypes showed a higher transforming growth factor-β1 serum level than the TT genotype (4.25 ± 2.50 ng/ml vs. 2.71± 1.76 ng/ml, P = 0.028) in controls.

Conclusion

Transforming growth factor-β1 T869C polymorphism, correlated with high serum transforming growth factor-β1 levels, is associated with susceptibility to acquired sick sinus syndrome.

The African-387 C>T TGFB1 variant is functional and associates with the ophthalmoplegic complication in juvenile myasthenia gravis

Although extraocular muscles are commonly affected by myasthenia gravis (MG) at presentation, a treatment-resistant ophthalmoplegic complication of MG (OP-MG) occurs in younger patients with African-genetic ancestry. In MG, pathogenic antibodies activate complement-mediated muscle damage and this may be potentiated in some OP-MG cases because of relative deficiency of decay-accelerating factor/CD55. Extending this argument, we hypothesized that OP-MG individuals may harbor African-specific polymorphisms in key genes influencing extraocular muscle remodeling. We screened the regulatory region of the transforming growth factor beta-1 (TGFB1) gene encoding the cytokine pivotal in muscle healing responses. We show the frequency of an African-specific polymorphism TGFB1 c.-387 T (rs11466316) among South Africans with African-genetic ancestry is higher than 1000 Genomes African controls (17.2% vs 4.8%; P<1 × 10(-7)), and associates with juvenile OP-MG (28%; P=0.043). Further, TGFB1 -387 C>T is functional because it represses the TGFB1 promoter construct basal activity by fivefold, and OP-MG fibroblasts (-387 C/T or T/T) have lower basal TGFB1 mRNA transcripts compared with controls (-387 C/C)(P=0.001). Co-transfections with Sp1 show less responsiveness of the -387 T promoter compared with wild-type -387 C (P=0.015). Our findings suggest that population-specific alleles may lower TGFB1 expression, thereby influencing OP-MG susceptibility by inhibiting extraocular muscle CD55 upregulation and/or altered endplate remodeling.

Polymorphism in TGFB1 is associated with worse non-relapse mortality and overall survival after stem cell transplantation with unrelated donors

Transforming growth factor β-1, encoded by the TGFB1 gene, is a cytokine that plays a central role in many physiological and pathogenic processes. We have sequenced TGFB1 regulatory region and assigned allelic genotypes in a large cohort of hematopoietic stem cell transplantation patients and donors. In this study, we analyzed 522 unrelated donor-patient pairs and examined the combined effect of all the common polymorphisms in this genomic region. In univariate analysis, we found that patients carrying a specific allele, 'p001', showed significantly reduced overall survival (5-year overall survival 30.7% for p001/p001 patients vs. 41.6% others; P=0.032) and increased non-relapse mortality (1-year non-relapse mortality: 39.0% vs. 25.4%; P=0.039) after transplantation. In multivariate analysis, the presence of a p001/p001 genotype in patients was confirmed as an independent factor for reduced overall survival [hazard ratio=1.53 (1.04-2.24); P=0.031], and increased non-relapse mortality [hazard ratio=1.73 (1.06-2.83); P=0.030]. In functional experiments we found a trend towards a higher percentage of surface transforming growth factor β-1-positive regulatory T cells after activation when the cells had a p001 allele (P=0.07). Higher or lower production of transforming growth factor β-1 in the inflammatory context of hematopoietic stem cell transplantation may influence the development of complications in these patients. Findings indicate that TGFB1 genotype could potentially be of use as a prognostic factor in hematopoietic stem cell transplantation risk assessment algorithms.

Pleiotropic Effects of Immune Responses Explain Variation in the Prevalence of Fibroproliferative Diseases

Many diseases are differentially distributed among human populations. Differential selection on genetic variants in ancestral environments that coincidentally predispose to disease can be an underlying cause of these unequal prevalence patterns. Selected genes may be pleiotropic, affecting multiple phenotypes and resulting in more than one disease or trait. Patterns of pleiotropy may be helpful in understanding the underlying causes of an array of conditions in a population. For example, several fibroproliferative diseases are more prevalent and severe in populations of sub-Saharan ancestry. We propose that this disparity is due to selection for an enhanced Th2 response that confers resistance to helminthic infections, and concurrently increases susceptibility to fibrosis due to the profibrotic action of Th2 cytokines. Many studies on selection of Th2-related genes for host resistance to helminths have been reported, but the pleiotropic impact of this selection on the distribution of fibrotic disorders has not been explicitly investigated. We discuss the disproportionate occurrence of fibroproliferative diseases in individuals of African ancestry and provide evidence that adaptation of the immune system has shaped the genetic structure of these human populations in ways that alter the distribution of multiple fibroproliferative diseases.

Study of the association of the T869C polymorphism of the transforming growth factor-β1 gene with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common multifactorial disorder characterized by hyperandrogenism, insulin resistance and chronic oligoanovulation. In addition, a number of females with PCOS have ovaries with multiple cysts, an irregular or no menstrual cycle and an imbalance of female hormones compared with normal controls. The transforming growth factor β1 (TGF‑β1) gene is one of the genes associated with obesity and type 2 diabetes, which are characteristic symptoms of PCOS. The present study, therefore, investigated the association between the T869C polymorphism of the TGF‑β1 gene, a single nucleotide polymorphism (SNP) of TGF‑β1 and PCOS. The genomic DNA from 285 patients with PCOS and 129 healthy control individuals was used in the present study. P<0.05 was considered to indicate a statistically significant difference between the groups. The present study findings suggested that the frequency of genotypes provided no significant association between the T869C polymorphism in the TGF‑β1 gene and patients with PCOS. Although the present study concluded that the T869C polymorphism in the TGF‑β1 gene is not associated with the pathogenesis of PCOS, further studies regarding the correlation between other SNPs of the TGF‑β1 gene and PCOS are required.

Association of Transforming Growth Factor Beta-1 (TGF-β1) Genetic Variation with Type 2 Diabetes and End Stage Renal Disease in Two Large Population Samples from North India

Geographic and ethnic differences impart an immense influence on the genetic susceptibility to Type 2 diabetes (T2D) and diabetic nephropathy (DN). Transforming growth factor-beta1 (TGF-β1), a ubiquitously expressed pro-fibrotic cytokine plays a pivotal role in mediating the hypertrophic and fibrotic manifestations of DN. The present study is aimed to study the association of TGF-β1 g.869T>C (rs1800470) and g.-509C>T (rs1800469) polymorphism in T2D and end stage renal disease (ESRD) cases from the two geographically and ethnically different populations from North India. A total of 1313 samples comprising 776 samples from Punjab (204 with ESRD, 257 without ESRD, and 315 healthy controls) and 537 samples from Jammu and Kashmir (150 with ESRD, 187 without ESRD, and 200 controls) were genotyped for TGF-β1 (rs1800470 and rs1800469) using ARMS-PCR. The CC genotype of rs1800470 increased ESRD risk by 3.1-4.5-fold in both populations. However, for rs1800469, the TT genotype provided 5.5-fold risk towards ESRD cases from Jammu and Kashmir and no risk for the cases from Punjab. The haplotype C-T conferred nearly a 2-3-fold risk towards T2D and ESRD and diplotype CC-CT conferred a 4-fold risk towards ESRD. Our results conclude that TGF-β1 (rs1800470) may increase the risk of both ESRD and T2D in both populations, but TGF-β1 (rs1800469) provided risk for only ESRD in the population of Jammu and Kashmir. The present study is one of the large sample sized genetic association studies of T2D and ESRD from Indian population and adds to the scholarship on global health omics.

Novel alleles of the transforming growth factor β-1 regulatory region and exon 1

Transforming growth factor β-1, encoded by the TGFB1 gene, is a cytokine that plays a central role in many physiologic and pathogenic processes with pleiotropic effects. Regulatory activity for this gene has been shown for 3.0 kb between positions -2665 and +423 from its translational start site. At least 17 TGFB1 regulatory region and exon 1 alleles have been defined on the basis of 18 polymorphic sites. Polymorphisms in TGFB1's regulatory region have been associated with differential levels of expression of this cytokine and to genetic risk in cancer and transplantation. In this report, we present 19 novel TGFB1 regulatory region and exon 1 alleles: p018-p036. Amplification of TGFB1's regulatory region was performed with an in-house protocol, and novel alleles were defined by either allele-specific amplification and/or molecular cloning of the amplicons, followed by sequencing in isolation. Three of these novel alleles (p018, p019, and p020) are shown to be formed by novel combinations of the aforementioned known polymorphic positions. Another 16 novel alleles are shown to carry additional known and unknown single-nucleotide polymorphisms. Polymorphism in TGFB1's regulatory region could have an impact on important processes, including embryogenesis, hematopoiesis, carcinogenesis, angiogenesis, fibrosis, immune responses, and transplantation, making its characterization necessary.

TGF-β1 genotype in pediatric migraine patients

There is no information about the role of transforming growth factor-beta 1 (TGF-β1) in the pathogenesis of pediatric migraine. This study included 100 consecutive children and adolescents in whom migraine was diagnosed and 88 healthy children and adolescents. The isolated genomic DNA was used as a template for TGFβ-1 (-800G/A, -509C/T, 869T/C [codon 10] and 915G/C [codon 25]) genotyping. The allelic frequency of 509C/T was significantly different between control and migraine without aura patients (P = .04). Codon 10 C/T genotypic and C10 C allelic frequency of TGF-β1 polymorphisms were significantly higher in migraine and migraine without aura patients versus healthy controls (P = .00; P = .00). To our knowledge, this is the first report dealing with the relationship between TGF-β1 genotype and migraine in the pediatric age group. Further studies related to this subject are needed, along with a search for new therapeutic agents with anti-inflammatory properties.

A novel association between TGFb1 and ADAMTS4 in coronary artery disease: A new potential mechanism in the progression of atherosclerosis and diabetes

Objective:

Coronary artery disease is characterized by atherosclerosis in the vessel wall. Recently, it has been thought that increasing LDL-binding capacity of subendothelial proteoglycan fragments that are formed by protease activity can be responsible for the initiation of atherosclerosis. ADAMTS4 is a member of the versican-degrading proteinases. In vitro studies demonstrated that TGFβ inhibits the expression of ADAMTS4 in macrophages. In this study, we aimed to investigate the role and association between TGFβ1 and ADAMTS4 in coronary artery disease.

Methods:

A total of 84 cases with atheroma plaque and 72 controls without plaque were analyzed. The severity of disease was determined by Gensini score. TGFβ1 gene polymorphisms were genotyped by the PCR-RFLP method. TGFβ1 and ADAMTS4 serum levels were measured by ELISA method. Statistical analyses of genotypes and their relationship with serum levels were performed by chi-square, student t test and ANOVA.

Results:

ADAMTS4 levels were higher in cases compared with controls (p<0.05). In the patient group, ADAMTS4 levels were higher than in controls and correlated with TGFβ1 serum levels (r=0.29; p<0.05) and severity of disease (r=0.20; p<0.05). The TGFβ1 gene CCA haplotype was associated with 3.3-fold increase in coronary artery disease (OR=3.26 95% CI 1.22-8.68; p<0.05). Unexpectedly, ADAMTS4 serum levels were also higher in diabetic cases (p=0.05).

Conclusion:

This study has demonstrated that ADAMTS4 may be responsible for the pathogenesis of atherosclerosis. This is the first report about the association between ADAMTS4 and TGFβ1 serum levels in the progression of atherosclerosis in CAD. Furthermore, it is seen that TGFβ1 haplotype can cause a genetic susceptibility to CAD in the Turkish population. To our knowledge, this is also the first report suggesting higher serum ADAMTS4 levels in diabetic patients.

Combined effects of TGFB1 +869 T/C and +915 G/C polymorphisms on acute rejection risk in solid organ transplant recipients: a systematic review and meta-analysis

Background

Transforming growth factor-beta 1(TGF-β1) is involved in the development of acute rejection (AR) episodes in solid organ transplant recipients; and a number of studies have been conducted to investigate the combined effects of human TGF-β1 gene (TGFB1) +869 T/C and +915 G/C polymorphisms on AR risk. However, the results obtained are inconclusive.

Methods

Eligible studies that investigated the haplotypic association between TGFB1 +869 T/C and +915 G/C polymorphisms and AR risk were comprehensively searched in the PUBMED, EMBASE, China National Knowledge Infrastructure, and Wanfang Database. Statistical analyses were performed by using STATA 12.0 and Review Manager 5.0.

Results

Fourteen eligible studies with 565 AR cases and 1219 non-AR cases were included. Overall, a significantly decreased risk was detected in patients carried with intermediate producer (IP) haplotypes (T/C G/C, T/T G/C, and C/C G/G) and/or low producer (LP) haplotypes (C/C G/C, C/C C/C, T/T C/C, and T/C C/C) compared with high producer (HP) haplotypes (T/T G/G and T/C G/G; IP vs. HP: OR = 0.75, 95% CI, 0.58–0.96, P _{heterogeneity}  = 0.238; IP/LP vs. HP: OR  = 0.77, 95% CI, 0.61–0.98, P _{heterogeneity}  = 0.144). In addition, subgroup analysis by transplant types demonstrated a similar association in patients receiving heart transplant (IP vs. HP: OR  = 0.32, 95% CI, 0.14–0.73, P _{heterogeneity}  = 0.790; IP/LP vs. HP: OR  = 0.41, 95% CI, 0.20–0.85, P _{heterogeneity}  = 0.320).

Conclusions

The current meta-analysis and systematic review indicated that recipient TGFB1 HP haplotypes were significantly associated with an increased risk for AR in solid organ transplant recipients, particularly patients receiving cardiac allograft.

Association between transforming growth factor beta-1 +869T/C polymorphism and acute rejection of solid organ allograft: A meta-analysis and systematic review

BACKGROUND

Transforming growth factor beta-1(TGFB1) is involved in the acute rejection (AR) episodes of solid organ transplant recipients. However, results from published studies on the association between donor/recipient TGFB1 +869T/C polymorphism and AR risk are conflicting and inconclusive.

METHODS

PUBMED, EMBASE, CNKI and Wanfang Database were searched to identify eligible studies investigating the association between donor/recipient TGFB1 +869T/C polymorphism and AR risk. Statistical analysis was performed by using STATA 10.0.

RESULTS

A total of 29 studies were included. Overall, the donor TGFB1 +869T/C polymorphism was significantly associated with AR risk in heterozygote comparison (CT vs. TT: OR = 1.67, 95%CI, 1.17-2.39; P heterogeneity=0.285) and dominant model (CC vs.

TC/TT

OR = 1.47, 95%CI, 1.05-2.06; P heterogeneity=0.445). In addition, subgroup analysis revealed that CT variant (CT vs. TT: OR = 1.97, 95%CI, 1.20-3.25; P heterogeneity = 0.777) and CC/CT genotype (CC/CT vs. TT: OR = 1.72, 95%CI, 1.07, 2.78; P heterogeneity = 0.619) within donors contributed to higher risk of AR in recipients administrated with CsA or FK506, compared with those applied only CsA. On the other hand, no significant association between recipient TGFB1 +869T/C polymorphism and AR was detected in all genetic models.

CONCLUSIONS

This meta-analysis and systematic review suggested that donor TGFB1 +869T/C polymorphism was significantly associated with AR of solid organ transplant recipients, and especially among patients in CsA/FK 506 group compared with those in CsA group.

Conditional radioresistance of Tet-inducible manganese superoxide dismutase bone marrow stromal cell lines

Mitochondrial targeted manganese superoxide dismutase is a major antioxidant enzyme, the levels of which modulate the response of cells, tissues and organs to ionizing irradiation. We developed a Tet-regulated MnSOD mouse (MnSOD(tet)) to examine the detailed relationship between cellular MnSOD concentration and radioresistance and carried out in vitro studies using bone marrow culture derived stromal cell lines (mesenchymal stem cells). Homozygous MnSOD(tet/tet) cells had low levels of MnSOD, reduced viability and proliferation, increased radiosensitivity, elevated overall antioxidant stores, and defects in cell proliferation and DNA strand-break repair. Doxycycline (doxy) treatment of MnSOD(tet/tet) cells increased MnSOD levels and radioresistance from ñ of 2.79 ± 1.04 to 8.69 ± 1.09 (P = 0.0060) and normalized other biologic parameters. In contrast, MnSOD(tet/tet) cells showed minimal difference in baseline and radiation induced mRNA and protein levels of TGF-β, Nrf2 and NF-κB and radiation induced cell cycle arrest was not dependent upon MnSOD level. These novel MnSOD(tet/tet) mouse derived cells should be valuable for elucidating several parameters of the oxidative stress response to ionizing radiation.

Association between transforming growth factor-beta 1 T869C polymorphism and ischemic stroke: a meta-analysis

Objective

To explore the association between transforming growth factor-beta1 (TGF-β1) T869C polymorphism and risk of ischemic stroke (IS) by performing a meta-analysis based on published articles.

Methods

Systematic electronic searches of PubMed, Science Direct, BIOSIS Previews, Chinese Biomedical Database, Chinese National Knowledge Infrastructure, and WANFANG Database were performed. The strength of the association was calculated by pooled odds ratios (ORs) with 95% confidence intervals (95%CIs). Subgroup analysis was conducted to explore potential sources of heterogeneity. Sensitivity analysis was performed to elucidate the stability of the outcomes. Publication bias was evaluated by Begg’s funnel plot and Egger’s test.

Results

A total of 6 studies involving 1701 cases were included. The overall estimates did not show any significant association between TGF-β1 T869C polymorphism and risk of IS under all genetic models (C vs. T: OR = 1.08,95%CI = 0.88–1.32; CC vs. TT:OR = 1.17,95%CI = 0.79–1.72; CT vs. TT: OR = 0.91, 95%CI = 0.68–1.22; CC+CT vs. TT: OR = 0.99, 95%CI = 0.73–1.35; CC vs. CT+TT: OR = 1.23, 95%CI = 0.95–1.59). Similar lacking associations were observed in subgroup analysis based on ethnicity and source of controls. When stratified by study design, significant increased association of IS risk was found in cohort studies under genetic models except recessive model(C vs. T: OR = 1.18, 95%CI = 1.05–1.32; CC vs. TT: OR = 1.40, 95%CI = 1.10–1.77; CT vs. TT: OR = 1.23, 95%CI = 1.02–1.49; CC+CT vs. TT: OR = 1.27, 95%CI = 1.03–1.57; CC vs. CT+TT, OR = 1.21, 95%CI = 0.99–1.47), whereas in case-control studies a significant decreased risk was detected under heterozygote comparison(CT vs. CC: OR = 0.72, 95%CI = 0.57–0.92). However, after correction for multiple testing, the associations were observed to be null significant in both cohort and case-control subgroups among all genetic models.

Conclusion

This meta-analysis suggested that current epidemiological studies of TGF-β1 T869C polymorphism are too inconsistent to draw a conclusion on the association with IS susceptibility. Given the small sample size and remarkable between-study heterogeneity, further well-designed prospective large-scale studies are warranted.

Gene polymorphism of transforming growth factor-β1 in Egyptian patients with type 2 diabetes and diabetic nephropathy

Role of the transforming growth factor-β1 (TGF-β1) gene polymorphisms located at codons 10 and 25 in the genetic predisposition to type 2 diabetes (T2D) and in diabetic nephropathy (DN) in Egyptian patients was investigated. A case control study was done for 99 unrelated Egyptian patients with T2D (50 DN(-) and 49 DN(+)) and 98 age- and sex-matched healthy controls. TGF-β1 T869C (codon 10) and G915C (codon 25) polymorphism detection was done by amplification refractory mutation system method. DN(+) patients were younger, with higher body mass index, serum triglycerides, serum creatinine, and lower serum albumin than those in DN(-) patients. Moderate and bad grades of diabetic control were associated with DN (P < 0.001). The TGF-β1 (T869C) C allele, TC and TC + CC genotypes were significantly higher in patients; the T allele and TT genotype were significantly higher in controls (Pc < 0.001). The TGF-β1 TC genotype was associated with DN (Pc < 0.05). Non-significant differences were detected between T2D patients and controls in the frequencies of TGF-β1 (G915C) alleles and genotypes. In conclusion, these preliminary data showed that the TGF-β1 codon 10 C allele, and C allele-containing genotypes may be susceptible, and T allele/TT genotype may be protective factors for T2D and DN(+) complications.

TGFB1 genetic polymorphisms and coronary heart disease risk: a meta-analysis

BACKGROUND

Genetic variations in TGFB1 gene have been studied in relation to coronary heart disease (CHD) risk, but the results were inconsistent.

METHODS

We performed a systematic review of published studies on the potential role of TGFB1 genetic variation in CHD risk. Articles that reported the association of TGFB1 genetic variants with CHD as primary outcome were searched via Medline and HuGE Navigator through July 2011. The reference lists from included articles were also reviewed.

RESULTS

Data were available from 4 studies involving 1777 cases and 7172 controls for rs1800468, 7 studies involving 5935 cases and 10677 controls for rs1800469, 7 studies involving 6634 cases and 9620 controls for rs1982073, 5 studies involving 5452 cases and 9999 controls for rs1800471, and 4 studies involving 5143 cases and 4229 controls for rs1800472. The pooled odds ratios (ORs) for CHD among minor T allele carriers of rs1800469, minor C allele carriers of rs1982073, and minor C allele carriers of rs1800471 versus homozygous major allele carriers was 1.14 (95% confidence interval [CI]: 1.05-1.24), 1.18 (95% CI: 1.04-1.35), and 1.16 (95% CI: 1.02-1.32), respectively. No substantial heterogeneity for ORs was detected among the included Caucasian populations for all SNPs. However, for rs1800471, the statistical significance disappeared after adjusting for potential publication bias. No significant association was found between rs1800468 and rs1800472 variants and CHD risk.

CONCLUSION

Minor allele carriers of two genetic variants (rs1800469 and rs1982073) in TGFB1 have a 15% increased risk of CHD.

Association of transforming growth factor β-1 (TGFB1) regulatory region polymorphisms with myasthenia gravis-related ophthalmoparesis

We investigated the association of an ophthalmoplegic complication developing in African myasthenia gravis (MG) subjects with polymorphisms in the regulatory region of TGFB1. We found significant associations with several putative functional single nucleotide polymorphisms (SNPs) (including two novel SNPs) that potentially alter transcription factor binding. Our data support a hypothesis that altered TGFB1 regulation may predispose individuals who harbour these SNPs to developing ophthalmoplegia as a result of increased TGF-β1 driven myofibrosis as a consequence to complement-mediated damage.

Association of transforming growth factor-β1 gene C-509T and T869C polymorphisms with atherosclerotic cerebral infarction in the Chinese: a case-control study

Background

Transforming growth factor-β1 (TGF-β1) is a multifunctional cytokine involved in inflammation and pathogenesis of atherosclerosis. There is scant information on the relation between variations within the TGF-β1 gene polymorphisms and risks of ischemic cerebrovascular diseases. Therefore, this case-controlled study was carried out to investigate the possible association of the TGF-β1 gene C-509T and T869C polymorphisms, and their combined genotypes with the risk of atherosclerotic cerebral infarction (CI) in the Chinese population.

Results

We recruited 164 CI patients and 167 healthy control subjects who were frequency-matched for age and gender. The frequencies of the -509TT genotype and T allele gene were significantly higher in the CI group (P = 0.007, P = 0.006). The frequencies of +869CC genotype and C allele were higher in the CI group (P = 0.002, P = 0.004). In the CI group, the individuals with -509TT genotype had a significantly higher level of plasma triglyceride (TG) (P = 0.017). +869CC genotype correlated significantly with higher level of plasma low density lipoprotein cholesterol (LDL-c) in the CI group (P = 0.015). With haplotype analysis, the frequency of the -509T/+869C combined genotype was significantly higher in the CI group than in controls (P < 0.001).

Conclusions

Our study suggests that C-509T and T869C gene polymorphisms in TGF-β1 may be a critical risk factor of genetic susceptibility to CI in the Chinese population.

Association with TGF-β1 gene polymorphisms and reproductive performance of Large white pig

As a multifunctional cytokine, transforming growth factor-beta1 (TGF-β1) was detected in the utero-placental interface during early pregnancy in the pig and believed to enhance trophoblast attachment to the endometrium. In this experiment, we selected TGF-β1 as the candidate gene affecting litter size in pigs. Four polymorphic loci of TGF-β1 gene were found by PCR-SSCP (single-strand conformation polymorphism) in Large white sows (n = 567): C→T mutation at 33nt in the intron 4; G→A mutation at 179nt in the intron 6; C→T mutation at 1043nt in the intron 6; GG→AA linkage mutations at 2490nt and 2494nt respectively. We haplotyped these SNPs as: CGCAA (denote as P) and TATGG (denote as K). The effects of three haplotypic combinations (HCs) of PP, PK and KK on litter sizes were investigated by a linear model. It was found that for the first parity litters, the least squares mean for total number born (TNB) of KK was 1.02 piglets/litter, higher than that of PK (p < 0.05), 0.49 piglets/litter higher than that of PP (p > 0.1). There were no significant differences between HCs on the second parity. The result indicated that KK HCs was significantly associated with pig litter size.

Association of polymorphisms within the transforming growth factor-β1 gene with diabetic nephropathy and serum cholesterol and triglyceride concentrations

AIM

The TGF-β gene participates in the development of chronic kidney disease. We investigated whether the 869 T > C, 915 G > C and -800 G > A polymorphisms of TGF-β1 are associated with diabetic nephropathy (DN).

METHODS

Polymorphisms were genotyped in 439 type 2 diabetes mellitus patients, 233 with diabetic nephropathy (DN+) and 206 without (DN-). The sample was characterized for relevant clinical and biochemical parameters.

RESULTS

The 869 T > C (P = 0.016; odds ratio (OR) = 1.818, 95% confidence interval (CI) = 1.128-2.930) and the 915 G > C polymorphisms (P = 0.008, OR = 4.073, 95% CI = 1.355-12.249) were associated with diabetic nephropathy. The 869 T > C variant was associated with total cholesterol levels: CC + CT genotypes had a mean cholesterol concentration of 5.62 ± 1.40 mmol/L vs a mean concentration of 5.15 ± 1.40 mmol/L for the TT genotype (P = 0.011). Triglycerides were also higher in CC + CT genotypes (2.49 ± 1.56 mmol/L) in comparison with TT homozygotes (2.1 ± 1.22 mmol/L, P = 0.042). Multivariate logistic regression showed that the polymorphisms 869 T > C and 915 G > C were independent predictors for DN (P = 0.049 and 0.046, respectively).

CONCLUSION

The 869 T > C and 915 G > C polymorphisms within the TGF-β1 gene were associated with DN+. Lower cholesterol and triglycerides levels were observed in TT homozygotes for the 869 T > C polymorphism. The TGF-β1 869 T allele seems to confer protection against DN+.

TGF-β1 869T/C polymorphism and ischemic stroke: sex difference in Chinese

BACKGROUND

Inflammation plays a pivotal role in the pathogenesis of atherosclerosis and of cerebrovascular complications. Transforming growth factor-β (TGF-β) is a pleiotropic cytokine with a central role in inflammation. To investigate whether polymorphisms of the TGF-β1 gene can modify the risk of ischemic stroke (IS) in Chinese population, we conduct this hospital-based, case-control study.

METHODS

Transforming growth factor-β1 genotype was determined in 450 Chinese patients (306 male and 144 female) with IS and 450 control subjects (326 male and 124 female).

RESULTS

Subjects carrying 869TT were susceptible to IS (odds ratio [OR] =1.58; P=0.003). Further analysis of IS data partitioned by gender revealed the female-specific association with 869T/C (OR=2.64; P=0.001).

CONCLUSIONS

Findings suggest that the TT genotype of 869T/C might be a risk factor of IS in Chinese, especially in females.

Polymorphisms in the transforming growth factor-beta1 gene and the risk of asthma: A meta-analysis

BACKGROUND AND OBJECTIVE

Polymorphisms in the transforming growth factor-beta1 (TGF-beta1) gene have been implicated in susceptibility to asthma, but a large number of studies have reported inconclusive results. A meta-analysis was performed to investigate the association between polymorphisms in the TGF-beta1 gene and asthma susceptibility.

METHODS

Searches were performed of Medline (Ovid), PubMed, the Chinese Biological Medicine Database (CBM), the Chinese Journals Full-text Database (CNKI), the Cochrane Library Database and the Web of Science, covering all papers published up to 30 April 2009. Statistical analysis was performed using Revman4.2.8 and STATA10.0 software.

RESULTS

Two polymorphisms (-509C/T and 915G/C(G25C)) were investigated in 14 studies, involving 2979 asthma patients and 4941 control subjects. The results showed that individuals carrying the -509T allele (TT+TC) had a 36% increased risk of asthma, when compared with homozygotes (-509CC) (OR 1.36, 95% CI: 1.12-1.65). However, there was no significant association with risk of asthma in carriers of the 915C allele (GC+CC) compared with 915GG homozygotes (OR 1.05, 95% CI: 0.65-1.70). In a subgroup analysis by ethnicity, the risk of asthma associated with the -509T allele was significantly elevated among Asians (OR 1.50, 95% CI: 1.04-2.17) but not Caucasians (OR 1.16, 95% CI: 1.00-1.36). In a subgroup analysis by age, the -509T allele was associated with a significantly elevated risk of asthma among adults (OR 1.45, 95% CI: 1.09-1.92) but not children (OR 1.19, 95% CI: 0.96-1.46).

CONCLUSIONS

This meta-analysis suggested that the -509C/T polymorphism in the TGF-beta1 gene may be a risk factor for asthma. To further evaluate gene-gene and gene-environment interactions between polymorphisms in the TGF-beta1 gene and asthma susceptibility, more studies involving thousands of patients are required.

Control of TCF-4 expression by VDR and vitamin D in the mouse mammary gland and colorectal cancer cell lines

Background

The vitamin D receptor (VDR) pathway is important in the prevention and potentially in the treatment of many cancers. One important mechanism of VDR action is related to its interaction with the Wnt/β-catenin pathway. Agonist-bound VDR inhibits the oncogenic Wnt/β-catenin/TCF pathway by interacting directly with β-catenin and in some cells by increasing cadherin expression which, in turn, recruits β-catenin to the membrane. Here we identify TCF-4, a transcriptional regulator and β-catenin binding partner as an indirect target of the VDR pathway.

Methodology/Principal Findings

In this work, we show that TCF-4 (gene name TCF7L2) is decreased in the mammary gland of the VDR knockout mouse as compared to the wild-type mouse. Furthermore, we show 1,25(OH)₂D₃ increases TCF-4 at the RNA and protein levels in several human colorectal cancer cell lines, the effect of which is completely dependent on the VDR. In silico analysis of the human and mouse TCF7L2 promoters identified several putative VDR binding elements. Although TCF7L2 promoter reporters responded to exogenous VDR, and 1,25(OH)₂D₃, mutation analysis and chromatin immunoprecipitation assays, showed that the increase in TCF7L2 did not require recruitment of the VDR to the identified elements and indicates that the regulation by VDR is indirect. This is further confirmed by the requirement of de novo protein synthesis for this up-regulation.

Conclusions/Significance

Although it is generally assumed that binding of β-catenin to members of the TCF/LEF family is cancer-promoting, recent studies have indicated that TCF-4 functions instead as a transcriptional repressor that restricts breast and colorectal cancer cell growth. Consequently, we conclude that the 1,25(OH)₂D₃/VDR-mediated increase in TCF-4 may have a protective role in colon cancer as well as diabetes and Crohn's disease.

Functional impact of sequence variation in the promoter region of TGFB1

Pathological deregulation of the transforming growth factor, beta 1 (TGFB1) pathway has been implicated in the development of several major diseases, including cancers. Regulatory variation in the TGFB1 gene may lead to altered TGFB1 expression and activity, and thus, modulate an individual's susceptibility to disease. Here, we performed a study of the functional relevance of cis-acting regulatory variation in the proximal promoter region of the TGFB1 gene. In a previous study, 9 promoter polymorphisms were identified in the 2kb region upstream of the transcription start site and 9 distinct promoter haplotypes were inferred from a panel of individuals from 5 distinct continental population groups. Following experimental validation, we found that the 2 major haplotypes significantly influenced TGFB1 transcriptional activity in an allele-specific manner and that 3 of the SNPs (-1886G>A, -509C>T and -1550DEL/AGG) altered DNA-protein complex formation. Though the biological relevance of these findings remains to be verified, our study suggests that polymorphisms in the TGFB1 promoter could indeed influence gene expression and potentially contribute to the pathogenesis of TGFB1 related diseases.

TNF, LTA and TGFB1 genotype distributions among acute graft-vs-host disease subsets after HLA-matched unrelated hematopoietic stem cell transplantation: a pilot study

Cytokine single nucleotide polymorphisms and consequent production levels have been associated with acute graft-vs-host disease (aGVHD) development. The aim of this pilot study was to determine whether polymorphisms in tumor necrosis factor (TNF), lymphotoxin alpha (LTA) and transforming growth factor beta 1 (TGFB1) showed any association with aGVHD severity. Novel alleles and polymorphisms were identified for each cytokine locus. Genotype distributions were examined in 38 recipient-donor pairs (all chronic myelogenous leukemia in the first chronic phase) with either low-grade (grades 0-I) or high-grade (grades III-IV) aGVHD. Although no significant differences were found, some trends were noted in genotype distributions among aGVHD-grade groups. Power calculations determined that substantially more pairs would be required to show significant associations in distributions among aGVHD-grade groups.

TGF-beta1 gene polymorphisms and primary vesicoureteral reflux in childhood

The aim of this study was to assess the association between the transforming growth factor-beta1 (TGF-beta1) gene polymorphisms rs1800469 (commonly known as T-509C) and rs1982073 (commonly known as Leu (10)-->Pro) and primary vesicoureteral reflux (VUR) and renal scarring. Using a case-control approach, we examined 121 children with primary VUR and 169 controls. Genotyping of the TGF-beta1 gene polymorphisms was performed by restriction fragment length polymorphism (RFLP) analysis. The (99m)Tc-DMSA- or (99m)Tc-unitiol-single photon emission computed tomography method was used to evaluate renal scars in 84 of 121 VUR children. Statistical analysis revealed differences in rs1800469 genotype frequencies between VUR patients and controls (p = 0.0021). Our data demonstrate that individuals homozygous for the TT genotype are at risk of primary VUR [odds ratio (95% confidence interval) = 2.7 (1.46-5.08)]. Distribution of the rs1982073 polymorphism was similar in VUR children and controls. In terms of renal scarring, patients were stratified into non-scar and scar subgroups, and no differences in the genotype frequencies of either polymorphism was found. Previous reports have shown that the TT genotype of the rs1800469 polymorphism is a risk factor for renal scarring in primary VUR, and the results of our study suggest that this same polymorphism is associated with susceptibility to this congenital uropathy.