Characterization of the Promoter Region of the Human Transforming Growth Factor-β1 Gene

The Erk1/2-EGR1 signaling pathway is involved in lipopolysaccharide-induced transforming growth factor-beta 1 expression in mouse macrophages

Numerous studies have demonstrated that lipopolysaccharide (LPS) stimulates TGF-β1 expression. Although studies have implicated the NF-κB/METTL3/METTL14 transactivation/m6A-dependent and AMPK-dependent signaling pathways are engaged in this process in a variety of cell types, the underlying regulatory mechanism in murine macrophages is still not fully understood. To address this issue, in vitro studies were performed using the murine macrophage cell line, RAW264.7. The results showed that LPS challenge resulted in a significant increase in TGF-β1 expression at both mRNA and protein levels. Subsequent studies revealed that the MAPK (including p38, Erk1/2, and JNK) and NF-κB signaling pathways were activated in response to LPS stimulation, but only blocking the Erk1/2 singling pathway completely abolished LPS-induced TGF-β1 expression. Further studies revealed that the levels of a downstream regulator of the Erk1/2 pathway, EGR1, were significantly increased after LPS treatment, and its knockdown significantly reduced LPS-induced Tgf-β1 expression levels. Finally, dual luciferase reporter and ChIP-PCR assays confirmed that EGR1 is a key transcription factor in the regulation of Tgf-β1 expression by binding to its promoter region in response to LPS stimulation. In conclusion, we elucidated the molecular events by which LPS regulates TGF-β1 expression in murine macrophages through the Erk1/2-EGR1 signaling pathway. These findings provide a conceptually novel pathway for LPS-induced TGF-β1 expression beyond the known NF-κB/METTL3/METTL14 transactivation/m6A-dependent and AMPK-dependent signaling pathways.

Interaction and Collaboration of SP1, HIF-1, and MYC in Regulating the Expression of Cancer-Related Genes to Further Enhance Anticancer Drug Development

Specificity protein 1 (SP1), hypoxia-inducible factor 1 (HIF-1), and MYC are important transcription factors (TFs). SP1, a constitutively expressed housekeeping gene, regulates diverse yet distinct biological activities; MYC is a master regulator of all key cellular activities including cell metabolism and proliferation; and HIF-1, whose protein level is rapidly increased when the local tissue oxygen concentration decreases, functions as a mediator of hypoxic signals. Systems analyses of the regulatory networks in cancer have shown that SP1, HIF-1, and MYC belong to a group of TFs that function as master regulators of cancer. Therefore, the contributions of these TFs are crucial to the development of cancer. SP1, HIF-1, and MYC are often overexpressed in tumors, which indicates the importance of their roles in the development of cancer. Thus, proper manipulation of SP1, HIF-1, and MYC by appropriate agents could have a strong negative impact on cancer development. Under these circumstances, these TFs have naturally become major targets for anticancer drug development. Accordingly, there are currently many SP1 or HIF-1 inhibitors available; however, designing efficient MYC inhibitors has been extremely difficult. Studies have shown that SP1, HIF-1, and MYC modulate the expression of each other and collaborate to regulate the expression of numerous genes. In this review, we provide an overview of the interactions and collaborations of SP1, HIF1A, and MYC in the regulation of various cancer-related genes, and their potential implications in the development of anticancer therapy.

Transforming growth factor beta-3 localization in the corneal response to epithelial-stromal injury and effects on corneal fibroblast transition to myofibroblasts

The purpose of this study was to evaluate the localization of TGF beta-3 in situ in unwounded rabbit corneas and corneas that had epithelial-stromal injuries produced by photorefractive keratectomy (PRK) in rabbits and to evaluate the in vitro effects of TGF beta-3 compared to TGF beta-1 on alpha-smooth muscle actin (α-SMA) protein expression and myofibroblast development in corneal fibroblasts. Forty-eight New Zealand white rabbits underwent either -3 diopter (D) or -9D PRK and were studied from one to eight weeks (four corneas in each group at each time point) after surgery with immunohistochemistry for TGF beta-3, laminin alpha-5, and alpha-smooth muscle actin (α-SMA). Rabbit corneal fibroblasts were treated with activated TGF beta-1 and/or TGF beta-3 at different concentrations and duration of exposure and studied with immunocytochemistry for myofibroblast development and the expression of α-SMA using Jess automated Western blotting. TGF beta-3 was detected at high levels in the stroma of unwounded corneas and corneas at one to eight weeks after -3D or -9D PRK, as well as in the epithelium and epithelial basement membrane (EBM). No difference was noted between corneas that healed with and without myofibroblast-mediated fibrosis, although TGF beta-3 was commonly associated with myofibroblasts. TGF beta-3 effects on corneal fibroblasts in vitro were similar to TGF beta-1 in stimulating transition to α-SMA-positive myofibroblasts and promoting α-SMA protein expression. The corneal stromal localization pattern of TGF beta-3 protein in unwounded corneas and corneas after epithelial-stromal injury was found to be higher and different from TGF beta-1 and TGF beta-2 reported in previous studies. TGF beta-3 had similar effects to TGF beta-1 in driving myofibroblast development and α-SMA expression in corneal fibroblasts cultured in medium with 1% fetal bovine serum.

Ral GTPase promotes metastasis of pancreatic ductal adenocarcinoma via elevation of TGF-β1 production

Pancreatic ductal adenocarcinoma (PDAC), caused by activating mutations in K-Ras, is an aggressive malignancy due to its early invasion and metastasis. Ral GTPases are activated downstream of Ras and play a crucial role in the development and progression of PDAC. However, the underlying mechanisms remain unclear. In this study, we investigated the mechanism of Ral-induced invasion and metastasis of PDAC cells using RalGAPβ-deficient PDAC cells with highly activated Ral GTPases. Array analysis and enzyme-linked immunosorbent assays revealed increased expression and secretion of TGF-β1 in RalGAPβ-deficient PDAC cells compared to control cells. Blockade of TGF-β1 signaling suppressed RalGAPβ deficiency-enhanced migration and invasion in vitro and metastasis in vivo to levels similar to controls. Phosphorylation of c-Jun N-terminal kinase (JNK), a repressor of TGF-β1 expression, was decreased by RalGAPβ deficiency. These results indicate that Ral contributes to invasion and metastasis of PDAC cells by elevating autocrine TGF-β1 signaling at least in part by decreasing JNK activity.

Downregulation of lncRNA Miat contributes to the protective effect of electroacupuncture against myocardial fibrosis

Background

Myocardial fibrosis changes the structure of myocardium, leads to cardiac dysfunction and induces arrhythmia and cardiac ischemia, threatening patients’ lives. Electroacupuncture at PC6 (Neiguan) was previously found to inhibit myocardial fibrosis. Long non-coding RNAs (lncRNAs) play a variety of regulatory functions in myocardial fibrosis, but whether electroacupuncture can inhibit myocardial fibrosis by regulating lncRNA has rarely been reported.

Methods

In this study, we constructed myocardial fibrosis rat models using isoproterenol (ISO) and treated rats with electroacupuncture at PC6 point and non-point as control. Hematoxylin–eosin, Masson and Sirius Red staining were performed to assess the pathological changes and collagen deposition. The expression of fibrosis-related markers in rat myocardial tissue were detected by RT-qPCR and Western blot. Miat, an important long non-coding RNA, was selected to study the regulation of myocardial fibrosis by electroacupuncture at the transcriptional and post-transcriptional levels. In post-transcriptional level, we explored the myocardial fibrosis regulation effect of Miat on the sponge effect of miR-133a-3p. At the transcriptional level, we studied the formation of heterodimer PPARG–RXRA complex and promotion of the TGF-β1 transcription.

Results

Miat was overexpressed by ISO injection in rats. We found that Miat can play a dual regulatory role in myocardial fibrosis. Miat can sponge miR-133a-3p in an Ago2-dependent manner, reduce the binding of miR-133a-3p target to the 3ʹUTR region of CTGF mRNA and improve the protein expression level of CTGF. In addition, it can also directly bind with PPARG protein, inhibit the formation of heterodimer PPARG–RXRA complex and then promote the transcription of TGF-β1. Electroacupuncture at PC6 point, but not at non-points, can reduce the expression of Miat, thus inhibiting the expression of CTGF and TGF-β1 and inhibiting myocardial fibrosis.

Conclusion

We revealed that electroacupuncture at PC6 point can inhibit the process of myocardial fibrosis by reducing the expression of lncRNA Miat, which is a potential therapeutic method for myocardial fibrosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-022-00615-6.

The effect of TGF-β1 polymorphisms on pulmonary disease progression in patients with cystic fibrosis

BACKGROUND

Transforming Growth Factor-β1 (TGF-β1) is a genetic modifier in patients with cystic fibrosis (CF). Several single nucleotide polymorphisms (SNPs) of TGF-β1 are associated with neutrophilic inflammation, lung fibrosis and loss of pulmonary function.

AIM

The aim of this study was to assess the relationship between genetic TGF-β1 polymorphisms and pulmonary disease progression in CF patients. Furthermore, the effect of TGF-β1 polymorphisms on inflammatory cytokines in sputum was investigated.

METHODS

56 CF-patients and 62 controls were genotyped for three relevant SNPs in their TGF-β1 sequence using the SNaPshot® technique. Individual "slopes" in forced expiratory volume in 1 s (FEV1) for all patients were calculated by using documented lung function values of the previous five years. The status of Pseudomonas aeruginosa (Pa) infection was determined. Sputum concentrations of the protease elastase, the serine protease inhibitor elafin and the cytokines IL-1β, IL-8, IL-6, TNF-α were measured after a standardized sputum induction and processing.

RESULTS

The homozygous TT genotype at codon 10 was associated with a lower rate of chronic Pa infection (p < 0.05). The heterozygous GC genotype at codon 25 was associated with lower lung function decline (p < 0.05). Patients with homozygous TT genotype at the promotor SNP showed higher levels of TNF-α (p < 0,05). Higher levels of TGF-β1 in plasma were associated with a more rapid FEV1 decline over five years (p < 0.05).

CONCLUSIONS

Our results suggest that polymorphisms in the TGF-β1 gene have an effect on lung function decline, Pa infection as well as levels of inflammatory cytokines. Genotyping these polymorphisms could potentially be used to identify CF patients with higher risk of disease progression. TGF-β1 inhibition could potentially be developed as a new therapeutic option to modulate CF lung disease.

Age-associated callus senescent cells produce TGF-β1 that inhibits fracture healing in aged mice

Cellular senescence plays an important role in human diseases, including osteoporosis and osteoarthritis. Senescent cells (SCs) produce the senescence-associated secretory phenotype to affect the function of neighboring cells and SCs themselves. Delayed fracture healing is common in the elderly and is accompanied by reduced mesenchymal progenitor cells (MPCs). However, the contribution of cellular senescence to fracture healing in the aged has not to our knowledge been studied. Here, we used C57BL/6J 4-month-old young and 20-month-old aged mice and demonstrated a rapid increase in SCs in the fracture callus of aged mice. The senolytic drugs dasatinib plus quercetin enhanced fracture healing in aged mice. Aged callus SCs inhibited the growth and proliferation of callus-derived MPCs (CaMPCs) and expressed high levels of TGF-β1. TGF-β-neutralizing Ab prevented the inhibitory effects of aged callus SCs on CaMPCs and promoted fracture healing in aged mice, which was associated with increased CaMPCs and proliferating cells. Thus, fracture triggered a significant cellular senescence in the callus cells of aged mice, which inhibited MPCs by expressing TGF-β1. Short-term administration of dasatinib plus quercetin depleted callus SCs and accelerated fracture healing in aged mice. Senolytic drugs represent a promising therapy, while TGF-β1 signaling is a molecular mechanism for fractures in the elderly via SCs.

Inhibition of CtBP-Regulated Proinflammatory Gene Transcription Attenuates Psoriatic Skin Inflammation

Psoriasis is a chronic immune-mediated disease characterized by excessive proliferation of epidermal keratinocytes and increased immune cell infiltration to the skin. Although it is well-known that psoriasis pathogenesis is driven by aberrant production of proinflammatory cytokines, the mechanisms underlying the imbalance between proinflammatory and anti-inflammatory cytokine expression are incompletely understood. In this study, we report that the transcriptional coregulators CtBP1 and 2 can transactivate a common set of proinflammatory genes both in the skin of imiquimod-induced mouse psoriasis model and in human keratinocytes and macrophages stimulated by imiquimod. We find that mice overexpressing CtBP1 in epidermal keratinocytes display severe skin inflammation phenotypes with increased expression of T helper type 1 and T helper type 17 cytokines. We also find that the expression of CtBPs and CtBP-target genes is elevated both in human psoriatic lesions and in the mouse imiquimod psoriasis model. Moreover, we were able to show that topical treatment with a peptidic inhibitor of CtBP effectively suppresses the CtBP-regulated proinflammatory gene expression and thus attenuates psoriatic inflammation in the imiquimod mouse model. Together, our findings suggest to our knowledge previously unreported strategies for therapeutic modulation of the immune response in inflammatory skin diseases.

TGF beta -1, -2 and -3 in the modulation of fibrosis in the cornea and other organs

The TGF beta-1, -2 and -3 isoforms are transcribed from different genes but bind to the same receptors and signal through the same canonical and non-canonical signal transduction pathways. There are numerous regulatory mechanisms controlling the action of each isoform that include the organ-specific cells producing latent TGF beta growth factors, multiple effectors that activate the isoforms, ECM-associated SLRPs and basement membrane components that modulate the activity and localization of the isoforms, other interactive cytokine-growth factor receptor systems, such as PDGF and CTGF, TGF beta receptor expression on target cells, including myofibroblast precursors, receptor binding competition, positive and negative signal transduction effectors, and transcription and translational regulatory mechanisms. While there has long been the view that TGF beta-1and TGF beta-2 are pro-fibrotic, while TGF beta-3 is anti-fibrotic, this review suggests that view is too simplistic, at least in adult tissues, since TGF beta-3 shares far more similarities in its modulation of fibrotic gene expression with TGF beta-1 and TGF beta-2, than it does differences, and often the differences are subtle. Rather, TGF beta-3 should be seen as a fibro-modulatory partner to the other two isoforms that modulates a nuanced and better controlled response to injury. The complex interplay between the three isoforms and numerous interactive proteins, in the context of the cellular milieu, controls regenerative non-fibrotic vs. fibrotic healing in a response to injury in a particular organ, as well as the resolution of fibrosis, when that occurs.

Deciphering the functional role of EGR1 in Prostaglandin F2 alpha induced luteal regression applying CRISPR in corpus luteum of buffalo

Background

PGF2α is essential for the induction of the corpus luteum regression which in turn reduces progesterone production. Early growth response (EGR) proteins are Cys2-His2-type zinc-finger transcription factor that are strongly linked to cellular proliferation, survival and apoptosis. Rapid elevation of EGR1 was observed after luteolytic dose of PGF2α. EGR1 is involved in the transactivation of many genes, including TGFβ1, which plays an important role during luteal regression.

Methods

The current study was conducted in buffalo luteal cells with the aim to better understand the role of EGR1 in transactivation of TGFβ1 during PGF2α induced luteal regression. Luteal cells from mid stage corpus luteum of buffalo were cultured and treated with different doses of PGF2α for different time durations. Relative expression of mRNAs encoding for enzymes within the progesterone biosynthetic pathway (3βHSD, CYP11A1 and StAR); Caspase 3; AKT were analyzed to confirm the occurrence of luteolytic event. To determine if EGR1 is involved in the PGF2α induced luteal regression via induction of TGFβ1 expression, we knocked out the EGR1 gene by using CRISPR/Cas9.

Result

The present experiment determined whether EGR1 protein expression in luteal cells was responsive to PGF2α treatment. Quantification of EGR1 and TGFβ1 mRNA showed significant up regulation in luteal cells of buffalo at 12 h post PGF2α induction. In order to validate the role of PGF2α on stimulating the expression of TGFβ1 by an EGR1 dependent mechanism we knocked out EGR1. The EGR1 ablated luteal cells were stimulated with PGF2α and it was observed that EGR1 KO did not modulate the PGF2α induced expression of TGFβ1. In PGF2α treated EGR1 KO luteal cell, the mRNA expression of Caspase 3 was significantly increased compared to PGF2α treated wild type luteal cells maintained for 12 h. We also studied the influence of EGR1 on steroidogenesis. The EGR1 KO luteal cells with PGF2α treatment showed no substantial difference either in the progesterone concentration or in StAR mRNA expression with PGF2α-treated wild type luteal cells.

Conclusion

These results suggest that EGR1 signaling is not the only factor which plays a role in the regulation of PGF2α induced TGFβ1 signaling for luteolysis.

CRISPRi-mediated functional analysis of lung disease-associated loci at non-coding regions

Genome-wide association studies have identified lung disease-associated loci; however, the functions of such loci are not well understood in part because the majority of such loci are located at non-coding regions. Hi-C, ChIP-seq and eQTL data predict potential roles (e.g. enhancer) of such loci; however, they do not elucidate the molecular function. To determine whether these loci function as gene-regulatory regions, CRISPR interference (CRISPRi; CRISPR/dCas9-KRAB) has been recently used. Here, we applied CRISPRi along with Hi-C, ChIP-seq and eQTL to determine the functional roles of loci established as highly associated with asthma, cystic fibrosis (CF), chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF). Notably, Hi-C, ChIP-seq and eQTL predicted that non-coding regions located at chromosome 19q13 or chromosome 17q21 harboring single-nucleotide polymorphisms (SNPs) linked to asthma/CF/COPD and chromosome 11p15 harboring an SNP linked to IPF interact with nearby genes and function as enhancers; however, CRISPRi indicated that the regions with rs1800469, rs2241712, rs12603332 and rs35705950, but not others, regulate the expression of nearby genes (single or multiple genes). These data indicate that CRISPRi is useful to precisely determine the roles of non-coding regions harboring lung disease-associated loci as to whether they function as gene-regulatory regions at a genomic level.

Transcriptional Regulation of Transforming Growth Factor β1 by Glucose: Investigation into the Role of the Hexosamine Biosynthesis Pathway

BACKGROUND

The hexosamine biosynthesis pathway (HBP) is hypothesized to mediate many of the adverse effects of hyperglycemia. We have shown previously that increased flux through this pathway leads to induction of the growth factor transforming growth factor-α (TGF-α) and to insulin resistance in cultured cells and transgenic mice. TGF-β is regulated by glucose and is involved in the development of diabetic nephropathy. We therefore hypothesized that the HBP was involved in the regulation of TGF-β by glucose in rat vascular and kidney cells.

METHODS

A plasmid containing the promoter region of TGF-β1 cloned upstream of the firefly luciferase gene was electroporated into rat aortic smooth muscle, mesangial, and proximal tubule cells. Luciferase activity was measured in cellular extracts from cells cultured in varying concentrations of glucose and glucosamine.

RESULTS

Glucose treatment of all cultured cells led to a time- and dose-dependent stimulation in TGF-β1 transcriptional activity, with high (20 mM) glucose causing a 1.4- to 2.0-fold increase. Glucose stimulation did not occur until after 12 hours and disappeared after 72 hours of treatment. Glucosamine was more potent than glucose, with 3 mM stimulating up to a 4-fold increase in TGFβ1-transcriptional activity. The stimulatory effect of glucosamine was also dose-dependent but was slower to develop and longer lasting than that of glucose.

CONCLUSIONS

The metabolism of glucose through the HBP mediates extracellular matrix production, possibly via the stimulation of TGF-β in kidney cells. Hexosamine metabolism therefore, may play a role in the development of diabetic nephropathy.

A Positive Feedback Loop of TET3 and TGF-β1 Promotes Liver Fibrosis

Pathological activation of TGF-β signaling is universal in fibrosis. Aberrant TGF-β signaling in conjunction with transdifferentiation of hepatic stellate cells (HSCs) into fibrogenic myofibroblasts plays a central role in liver fibrosis. Here we report that the DNA demethylase TET3 is anomalously upregulated in fibrotic livers in both humans and mice. We demonstrate that in human HSCs, TET3 promotes profibrotic gene expression by upregulation of multiple key TGF-β pathway genes, including TGFB1. TET3 binds to target gene promoters, inducing demethylation, which in turn facilitates chromatin remodeling and transcription. We also reveal a positive feedback loop between TGF-β1 and TET3 in both HSCs and hepatocytes. Furthermore, TET3 knockdown ameliorates liver fibrosis in mice. Our results uncover a TET3/TGF-β1 positive feedback loop as a crucial determinant of liver fibrosis and suggest that inhibiting TET3 may represent a therapeutic strategy for liver fibrosis and perhaps other fibrotic diseases.

Type 2 diabetes-associated polymorphisms correlate with SIRT1 and TGF-β1 gene expression

The polymorphisms rs3758391 and rs1800470 located in SIRT1 and TGF-β1 have been associated with type 2 diabetes in different populations but its functional effect is not clear. In this study, we evaluated their effect on the expression of SIRT1 and TGF-β1 in peripheral blood as well as their participation in the formation of DNA-protein complexes in a pancreas-derived cell line. It has been described that SIRT1 and TGF-β1 participate in cell growth and regulation of production and secretion of insulin in the pancreas. Anthropometric and biochemical profiles of 127 adults were measured. Genotypes for rs3758391 and rs1800470 were determined using TaqMan assays. Expression analysis of SIRT1 and TGF-β1 were performed using real-time PCR. Gene expression of these genes increased 1.8 ± 0.6- and 1.3 ± 0.6-fold in patients carrying the TT genotype of rs3758391 and rs1800470 when compared to carriers of the CC genotype. Then, we tested whether these single-nucleotide polymorphisms (SNPs) (and rs932658, which is in linkage disequilibrium with rs3758391) are located in regulatory DNA-protein binding sites by electrophoretic mobility shift assays using nuclear extract from the pancreas-derived cell line BxPC-3. The electrophoretic mobility shift assay showed no binding of nuclear proteins to DNA. In conclusion, the genotypes of rs3758391 and rs1800470 are associated with modifications in the expression of the genes SIRT1 and TGF-β1, respectively, but none of the tested SNPs are located in regulatory DNA-protein binding sites.

MPPED2 Polymorphism Is Associated With Altered Systemic Inflammation and Adverse Trauma Outcomes

Trauma is a leading cause of morbidity and mortality. It is unclear why some trauma victims follow a complicated clinical course and die, while others, with apparently similar injury characteristics, do not. Interpatient genomic differences, in the form of single nucleotide polymorphisms (SNPs), have been associated previously with adverse outcomes after trauma. Recently, we identified seven novel SNPs associated with mortality following trauma. The aim of the present study was to determine if one or more of these SNPs was also associated with worse clinical outcomes and altered inflammatory trajectories in trauma survivors. Accordingly, of 413 trauma survivors, DNA samples, full blood samples, and clinical data were collected at multiple time points in the first 24 h and then daily over 7 days following hospital admission. Subsequently, single-SNP groups were created and outcomes, such as hospital length of stay (LOS), ICU LOS, and requirement for mechanical ventilation, were compared. Across a broad range of Injury Severity Scores (ISS), patients carrying the rs2065418 TT SNP in the metallophosphoesterase domain-containing 2 (MPPED2) gene exhibited higher Marshall MODScores vs. the control group of rs2065418 TG/GG patients. In patients with high-severity trauma (ISS ≥ 25, n = 94), those carrying the rs2065418 TT SNP in MPPED2 exhibited higher Marshall MODScores, longer hospital LOS (21.8 ± 2 days), a greater requirement for mechanical ventilation (9.2 ± 1.4 days on ventilator, DOV), and higher creatinine plasma levels over 7 days vs. the control group of rs2065418 TG/GG high-severity trauma patients (LOS: 15.9 ± 1.2 days, p = 0.03; DOV: 5.7 ± 1 days, p = 0.04; plasma creatinine; p < 0.0001 MODScore: p = 0.0003). Furthermore, rs2065418 TT patients with ISS ≥ 25 had significantly different plasma levels of nine circulating inflammatory mediators and elevated dynamic network complexity. These studies suggest that the rs2065418 TT genotype in the MPPED2 gene is associated with altered systemic inflammation, increased organ dysfunction, and greater hospital resource utilization. A screening for this specific SNP at admission might stratify severely injured patients regarding their lung and kidney function and clinical complications.

Chemoprevention of gastric cancer by Helicobacter pylori eradication and its underlying mechanism

The cascade of gastric cancer, a leading cause of cancer incidence and mortality, is multifactorial. Helicobacter pylori (HP) infection plays a major role in gastric cancer (GC), and there has been an accumulation of data regarding the chemopreventive effect of HP eradication. However, it remains unclear how HP infection causes GC and how HP eradication prevents GC. To clarify this issue, the following approaches were performed in this review article. First, how HP-induced atrophic gastritis (AG) and intestinal metaplasia (IM) provoke the development of GC is shown, followed by how long HP eradication takes to induce a reversible change in AG and IM. Second, epigenetic studies of PTPN6, MOS, DCC, CRK, and VAV1 were performed in noncancerous gastric specimens in terms of HP status. Among these genes, MOS was found to be a possible surrogate marker for GC development. HP eradication decreased aberrant DNA methylation in a gene-specific manner, and MOS played a role in metachronous gastric neoplasms. Third, transforming growth factor-β1 (TGF-β1) and TGF-β1-induced epithelial-mesenchymal transition (EMT) markers were investigated in gastric mucosa. HP infection triggered the TGF-β1-induced EMT pathway and caused the emergence of GC stem cells, such as CD44v8-10. When HP was eradicated, these two pathways were inhibited. Finally, a 2222 cohort study showed that HP eradication significantly decreased the risk of noncardiac GC. Taken together, HP eradication is effective as a primary GC prevention method, and its underlying mechanism includes reversibility of AG and IM, methylation, EMT, and stem cells.

CGK062, a small chemical molecule, inhibits cancer upregulated gene 2‑induced oncogenesis through NEK2 and β‑catenin

The mechanisms through which cancer‑upregulated gene 2 (CUG2), a novel oncogene, affects Wnt/β‑catenin signaling, essential for tumorigenesis, are unclear. In this study, we aimed to elucidate some of these mechanisms in A549 lung cancer cells. Under the overexpression of CUG2, the protein levels and activity of β‑catenin were evaluated by western blot analysis and luciferase assay. To examine a biological consequence of β‑catenin under CUG2 overexpression, cell migration, invasion and sphere formation assay were performed. The upregulation of β‑catenin induced by CUG2 overexpression was also accessed by xenotransplantation in mice. We first found that CUG2 overexpression increased β‑catenin expression and activity. The suppression of β‑catenin decreased cancer stem cell (CSC)‑like phenotypes, indicating that β‑catenin is involved in CUG2‑mediated CSC‑like phenotypes. Notably, CUG2 overexpression increased the phosphorylation of β‑catenin at Ser33/Ser37, which is known to recruit E3 ligase for β‑catenin degradation. Moreover, CUG2 interacted with and enhanced the expression and kinase activity of never in mitosis gene A‑related kinase 2 (NEK2). Recombinant NEK2 phosphorylated β‑catenin at Ser33/Ser37, while NEK2 knockdown decreased the phosphorylation of β‑catenin, suggesting that NEK2 is involved in the phosphorylation of β‑catenin at Ser33/Ser37. Treatment with CGK062, a small chemical molecule, which promotes the phosphorylation of β‑catenin at Ser33/Ser37 through protein kinase C (PKC)α to induce its degradation, reduced β‑catenin levels and inhibited the CUG2‑induced features of malignant tumors, including increased cell migration, invasion and sphere formation. Furthermore, CGK062 treatment suppressed CUG2‑mediated tumor formation in nude mice. Taken together, the findings of this study suggest that CUG2 enhances the phosphorylation of β‑catenin at Ser33/Ser37 by activating NEK2, thus stabilizing β‑catenin. CGK062 may thus have potential for use as a therapeutic drug against CUG2‑overexpressing lung cancer cells.

Cancer upregulated gene (CUG)2 elevates YAP1 expression, leading to enhancement of epithelial-mesenchymal transition in human lung cancer cells

Although our previous studies have showed that a novel oncogene, cancer upregulated gene (CUG)2 induced epithelial-mesenchymal transition (EMT), the detailed molecular mechanism remains unknown. Because several lines of evidence documented that Yes-Associated Protein (YAP)1 is closely associated with cancer stem cell (CSC)-like phenotypes including EMT, stemness, and drug resistance, we wondered if YAP1 is involved in CUG2-induced EMT. We herein found that the overexpression of CUG2 increased YAP1 expression at the transcriptional as well as protein levels. Chromatin immunoprecipitation assay revealed that the elevated YAP1 transcripts are attributed to c-Jun and AP2 bindings to the YAP1 promoter. Akt and MAPK kinases including ERK, JNK, and p38 MAPK enhanced the level of YAP1 protein. In spite of a close relationship between β-catenin and YAP1, not β-catenin but NEK2 played the role in increasing YAP1 expression. Silencing YAP1 inhibited CUG2-induced cell migration and invasion. N-cadherin and vimentin expressions were decreased during YAP1 knockdown. The suppression of YAP1 diminished TGF-β transcriptional activity and expression as well as phosphorylation level of Smad2 and Twist protein. Conversely, LY2109761 or Smad2 siRNA treatment reduced YAP1 protein levels, indicating a close interplay between YAP1 and TGF-β signaling. Taken together, we suggest that CUG2 induces up-regulation of YAP1 expression, leading to enhancing CUG2-induced EMT via a close crosstalk between YAP1 and TGF-β signaling.

Activation of renal profibrotic TGFβ controlled signaling cascades by calcineurin and mTOR inhibitors

The calcineurin inhibitors (CNI) cyclosporine A (CsA) and tacrolimus represent potent immunosuppressive agents frequently used for solid organ transplantation and treatment of autoimmune disorders. Despite of their immense therapeutic benefits, residual fibrosis mainly in the kidney represents a common side effect of long-term therapy with CNI. Regardless of the immunosuppressive action, an increasing body of evidence implicates that a drug-induced increase in TGFβ and subsequent activation of TGFβ-initiated signaling pathways is closely associated with the development and progression of CNI-induced nephropathy. Mechanistically, an increase in reactive oxygen species (ROS) generation due to drug-induced changes in the intracellular redox homeostasis functions as an important trigger of the profibrotic signaling cascades activated under therapy with CNI. Although, inhibitors of the mechanistic target of rapamycin (mTOR) kinase have firmly been established as alternative compounds with a lower nephrotoxic potential, an activation of fibrogenic signaling cascades has been reported for these drugs as well. This review will comprehensively summarize recent advances in the understanding of profibrotic signaling events modulated by these widely used compounds with a specific focus put on mechanisms occurring independent of their respective immunosuppressive action. Herein, the impact of redox modulation, the activation of canonical TGFβ and non-Smad pathways and modulation of autophagy by both classes of immunosuppressive drugs will be highlighted and discussed in a broader perspective. The comprehensive knowledge of profibrotic signaling events specifically accompanying the immunomodulatory activity of these widely used drugs is needed for a reliable benefit-risk assessment under therapeutic regimens.

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.

Cancer upregulated gene 2 induces epithelial-mesenchymal transition of human lung cancer cells via TGF-β signaling

Cancer upregulated gene 2 (CUG2) enhances cell migration and invasion, but the underlying mechanism has not been revealed. Herein, CUG2 decreased the expression of E-cadherin and increased the expression of N-cadherin and vimentin, characteristics of the epithelial-mesenchymal transition (EMT). A CUG2 deletion mutant, lacking interaction with nucleophosmin 1 (NPM1), or suppression of NPM1 reduced wound healing and cell invasion, indicating that CUG2-mediated EMT requires NPM1. CUG2 enhanced activation of Smad2/3 and expression of Snail and Twist, while the CUG2 silence decreased these TGF-β signaling pathways, leading to suppression of EMT. NPM silence also inhibited the CUG2-induced TGF-β signaling. These results suggest that TGF-β signaling is involved in CUG2-induced EMT. Treatment with EW-7197, a novel inhibitor of TGF-β signaling, diminished CUG2-mediated EMT and inhibition of Akt, ERK, JNK, and p38 MAPK, non-canonical TGF-β signaling molecules, also decreased expression of Smad2/3, Snail and Twist, leading to inhibition of EMT. The results confirm that TGF-β signaling is essential for CUG2-mediated EMT. Interestingly, TGF-β enhanced CUG2 expression. We further found that both CUG2-induced TGF-β production and TGF-β-induced CUG2 up-regulation required a physical interaction between Sp1 and Smad2/3 in the CUG2 and TGF-β promoter, as demonstrated by a promoter reporter assay, immunoprecipitation, and ChIP assay. These results indicated close crosstalk between CUG2 and TGF-β. Conversely, suppression of CUG2 or NPM1 did not completely inhibit TGF-β-induced EMT, indicating that the effect of TGF-β on EMT is dominant over the effect of CUG2 on EMT. Collectively, our findings suggest that CUG2 induces the EMT via TGF-β signaling.

Influence of cytokine gene polymorphism on the risk of rheumatic heart disease - A meta-analysis

RHD is an inflammatory disease resulting from interactive immune, genetic, and environmental factors. Various, epidemiological studies have shown the association of genetic variants of cytokine genes with a predisposition to RHD. However, the results from different populations are inconsistent. Therefore, we carried out a meta- analysis of twenty-three published case-control studies and the results indicated that TGF-β1 +869 T/C (T vs. C: OR = 7.68, 95% CI = 1.62-36.50; TT + CT vs. CC OR = 1.83, 95%CI = 1.39-2.41), TGF-β1-509 (T vs. C: OR = 2.76, 95% CI = 1.33-5.75), TNF-α(AA vs. GG: OR = 4.93,95% CI = 2.83-8.58; A vs. G: OR = 2.15, 95% CI = 1.13-4.12) and IL-1β -511C/T (CC + CT vs. TT: OR = 1.35, 95%CI = 1.02-1.78; C vs. T: OR = 2.36, 95% CI = 1.66-3.37) were significantly associated with increased risk of RHD. On the other hand, IL-10(-1082)G/A polymorphism (GA vs. AA: OR = 0.91, 95% CI = 0.36-2.33; G vs. A: OR = 1.90, 95% CI = 0.58-6.22) and IL-6-174 G/C (CC + GC vs. GG: OR = 0.68, 95%CI = 0.32-1, C vs. G: OR = 1.14, 95% CI = 0.82-1.60) were not associated with modified RHD risk. The meta-analysis results were similar in Asians and non-Asians. Therefore, cytokine gene polymorphisms play important role in the genetic susceptibility of RHD in rheumatic fever patients.

Transmission analysis of TGFB1 gene polymorphisms in non-syndromic cleft lip with or without cleft palate

OBJECTIVES

Transforming growth factor beta1 (TGF-β1) plays a significant role in craniofacial development. Previous linkage studies reported that the TGF-β1-locus at 19q13.1 harbour predisposing genes for non-syndromic oral clefts. In the present study case parents triads were evaluated to find the transmission effects of genetic variants in TGF- β1 towards non-syndromic cleft lip or palate (NSCL/P).

METHODS

Using allelic discrimination method148 families (case-parent triads) were assessed for single nucleotide polymorphisms (SNPs) in TGF-β1 gene. The SNPs were checked for mendelian errors and Hardy-Weinberg equilibrium (HWE). Transmission disequilibrium test and haplotype frequencies were estimated.

RESULTS

The TGF-β1 SNPs showed very low minor allele frequencies (MAFs) and observed heterozygosity (Hobs). The transmission disequilibrium test (TDT) and parent-of-origin likelihood ratio tests (PO-LRT) were not significant for any of the SNPs tested. Strong linkage disequilibrium (r2 = 0.722) was found between rs1800469 and rs1800470 SNPs. Haplotype analysis ignoring parent of origin showed strong evidence of excess transmission but it is not significant (p-value = 0.293).

CONCLUSION

Transmission of minor alleles were not observed from either parent indicating that the TGF-β1 gene polymorphisms by themselves do not confer risk for non-syndromic oral clefts but, rather, modify the stability and the activation process of TGF-β1. As the number of families included in the study are less, results must be considered still preliminary and require replication using more families.

LIM-Only Protein FHL2 Is a Negative Regulator of Transforming Growth Factor β1 Expression

Transforming growth factor β1 (TGF-β1) is a master cytokine in many biological processes, including tissue homeostasis, epithelial-to-mesenchymal transition, and wound repair. Here, we report that four and a half LIM-only protein 2 (FHL2) is a critical regulator of TGF-β1 expression. Devoid of a DNA-binding domain, FHL2 is a transcriptional cofactor that plays the role of coactivator or corepressor, depending on the cell and promoter contexts. We detected association of FHL2 with the TGF-β1 promoter, which showed higher activity in Fhl2^-/- cells than in wild-type (WT) cells in a reporter assay. Overexpression of FHL2 abrogates the activation of the TGF-β1 promoter, whereas the upregulation of TGF-β1 gene transcription correlates with reduced occupancy of FHL2 on the promoter. Moreover, ablation of FHL2 facilitates recruitment of RNA polymerase II on the TGF-β1 promoter, suggesting that FHL2 may be involved in chromatin remodeling in the control of TGF-β1 gene transcription. Enhanced expression of TGF-β1 mRNA and cytokine was evidenced in the livers of Fhl2^-/- mice. We tested the in vivo impact of Fhl2 loss on hepatic fibrogenesis that involves TGF-β1 activation. Fhl2^-/- mice developed more severe fibrosis than their WT counterparts. These results demonstrate the repressive function of FHL2 on TGF-β1 expression and contribute to the understanding of the TGF-β-mediated fibrogenic response.

Persicarin isolated from Oenanthe javanica protects against diabetes-induced oxidative stress and inflammation in the liver of streptozotocin-induced type 1 diabetic mice

Persicarin is one of the major components of the Oenanthe javanica (water dropwort). The present study was aimed to evaluate the role of persicarin in the hepatic tissue of streptozotocin-induced type 1 diabetic mice. Diabetes was induced by single intra-peritoneal injection of streptozotocin (120 mg/kg body weight) and then oral administration of persicarin at a dose 2.5 and 5 mg/kg body weight for 10 days. Serum and hepatic glucose levels were increased in diabetic control mice, while persicarin treatment groups were markedly reduced. Also, the increased levels of ALT and AST in serum were improved by persicarin. In our results revealed that persicarin suppressed increased oxidative stress parameter (reactive oxygen species, peroxinitrite, and thiobarbituric acid-reactive substance), nicotinamide adenine dinucleotide phosphate oxidase subunit (Nox-4 and P47^phox) and inflammatory related makers (NF-κB, AP-1, TGF-β, COX-2, and iNOS). These results suggest that persicarin protects against liver damage by attenuating oxidative stress and inflammatory response under hyperglycemic conditions. Thus, persicarin could perform as a potential therapeutic agent for the treatment of diabetic mellitus.

Dysregulation of TGFβ1 Activity in Cancer and Its Influence on the Quality of Anti-Tumor Immunity

TGFβ1 is a pleiotropic cytokine that exhibits a variety of physiologic and immune regulatory functions. Although its influence on multiple cell types is critical for the regulation of numerous biologic processes in the host, dysregulation of both TGFβ1 expression and activity is frequently observed in cancer and contributes to various aspects of cancer progression. This review focuses on TGFβ1’s contribution to tumor immune suppression and escape, with emphasis on the influence of this regulatory cytokine on the differentiation and function of dendritic cells and T cells. Clinical trials targeting TGFβ1 in cancer patients are also reviewed, and strategies for future therapeutic interventions that build on our current understanding of immune regulation by TGFβ1 are discussed.

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.

Effects of Two Common Promoter Polymorphisms of Transforming Growth Factor-β1 on Breast Cancer Risks in Ahvaz, West South of Iran

BACKGROUND

Transforming growth factor-β1 (TGF-β1) has a critical role in breast cancer initiation and progression.

OBJECTIVES

We have investigated the possible differences in two promoter polymorphisms (-509C/T and -800G/A) of TGF-β1 gene between breast cancer cases and controls.

PATIENTS AND METHODS

A total of 100 patients with confirmed breast cancer and 100 subjects without breast cancer was selected. Two promoter polymorphisms (-509C/T and -800G/A) of TGF-β1 gene were genotyped using PCR-based restriction fragment length polymorphism (RFLP) method.

RESULTS

The allele frequencies were 63% for C allele and 37% for T allele of SNP -509C/T and 66% for G allele and 34% for A allele of SNP -800G/A. Although no significant difference has observed between two groups, according to the genotype distribution, However, the TT genotype of -509 and AA genotype of -800 was significantly associated with breast cancer risk [odds ratio (OR) = 2.409; 95% confidence interval (CI) = 1.087 - 5.337, P = 0.030; and OR = 2.383; CI = 1.039 - 5.40, P = 0.040, respectively]. In addition, a multinomial logistic regression model shown, homozygous of -800 G/A (OR = 0.570; 95% CI = 0.362 - 0.896, P = 0.015); and HDL-C (OR = 0.935; 95% CI = 0.906 - 0.965, P < 0.001) were the selected variables associated with the presence of breast cancer. Haplotype analysis has shown no significant association between TGF-β1 haplotypes and breast cancer risk.

CONCLUSIONS

Our results indicated that among two promoter polymorphisms of the TGF-β1gene, -800G/A compared to -509C/T is more associated with breast cancer.

Hepatitis C virus infection stimulates transforming growth factor-β1 expression through up-regulating miR-192

The objective of this study was to determine the molecular mechanisms underlying chronic liver injury and fibrosis caused by hepatitis C virus (HCV). This study revealed that miR-192 expreßsion was induced by HCV infection without affecting viral replication. However, viral-induced miR-192 up-regulated transforming growth factor-ß1 (TGF-ß1) expreßsion in liver cells at transcriptional level. TGF-ß1 stimulation by HCV-induced miR-192 was caused through ZEB1 down-regulation and TGF-ß1 increased miR-192 level via positive feedback pathway. Increase in miR-192 expreßsion by HCV infection was due to HCV core protein released and/or expressed by viral infection. TGF-ß1 promoter activity was also increased by HCV core protein in liver cells. Taken together, HCV infection resulted in increased TGF-ß1 transcription in hepatocytes through ZEB1 down-regulation by HCV core-mediated miR-192 stimulation. Importantly, miR-192 inhibition with anti-miR-192 rescued ZEB1 expression down-regulated by HCV infection, thus reducing the level of TGF-ß1 expression increased by HCV infection in hepatocytes. These results suggest a novel mechanism of HCV-mediated liver fibrogenesis with miR-192 being a potential molecular target to ameliorate viral pathogenesis.

SARS coronavirus papain-like protease induces Egr-1-dependent up-regulation of TGF-β1 via ROS/p38 MAPK/STAT3 pathway

SARS coronavirus (SARS-CoV) papain-like protease (PLpro) has been identified in TGF-β1 up-regulation in human promonocytes (Proteomics 2012, 12: 3193-205). This study investigates the mechanisms of SARS-CoV PLpro-induced TGF-β1 promoter activation in human lung epithelial cells and mouse models. SARS-CoV PLpro dose- and time-dependently up-regulates TGF-β1 and vimentin in A549 cells. Dual luciferase reporter assays with TGF-β1 promoter plasmids indicated that TGF-β1 promoter region between -175 to -60, the Egr-1 binding site, was responsible for TGF-β1 promoter activation induced by SARS-CoV PLpro. Subcellular localization analysis of transcription factors showed PLpro triggering nuclear translocation of Egr-1, but not NF-κB and Sp-1. Meanwhile, Egr-1 silencing by siRNA significantly reduced PLpro-induced up-regulation of TGF-β1, TSP-1 and pro-fibrotic genes. Furthermore, the inhibitors for ROS (YCG063), p38 MAPK (SB203580), and STAT3 (Stattic) revealed ROS/p38 MAPK/STAT3 pathway involving in Egr-1 dependent activation of TGF-β1 promoter induced by PLpro. In a mouse model with a direct pulmonary injection, PLpro stimulated macrophage infiltration into lung, up-regulating Egr-1, TSP-1, TGF-β1 and vimentin expression in lung tissues. The results revealed that SARS-CoV PLpro significantly triggered Egr-1 dependent activation of TGF-β1 promoter via ROS/p38 MAPK/STAT3 pathway, correlating with up-regulation of pro-fibrotic responses in vitro and in vivo.

Functional activity of the porcine Gnrhr2 gene promoter in testis-derived cells is partially conferred by nuclear factor-κB, specificity protein 1 and 3 (SP1/3) and overlapping early growth response 1/SP1/3 binding sites

Unlike the classical gonadotropin-releasing hormone (GnRH1), the second mammalian isoform (GnRH2) is ubiquitously expressed, suggesting a divergent function. Indeed, we demonstrated that GnRH2 governs LH-independent testosterone secretion in porcine testes via interaction with its receptor (GnRHR2) on Leydig cells. Transient transfections with luciferase reporter vectors containing 3009bp of 5' flanking sequence for the porcine Gnrhr2 gene (-3009pGL3) revealed promoter activity in all 15 cell lines examined, including swine testis-derived (ST) cells. Therefore, ST cells were utilized to explore the molecular mechanisms underlying transcriptional regulation of the porcine Gnrhr2 gene in the testis. Reporter plasmids containing progressive 5' deletions of the Gnrhr2 promoter indicated that the -708/-490 region contained elements critical to promoter activity. Electrophoretic mobility shift assays (EMSAs) with radiolabeled oligonucleotides spanning the -708/-490bp region and ST nuclear extracts, identified specific binding complexes for the -513/-490, -591/-571 and -606/-581bp segments of promoter. Antibody addition to EMSAs indicated that the p65 and p52 subunits of nuclear factor-κB (NF-κB) comprised the specific complex bound to the oligonucleotide probe for the -513/-490bp promoter region, specificity protein (SP) 1 and 3 bound the -591/-571bp probe and early growth response 1 (EGR1), SP1 and SP3 bound the -606/-581 radiolabeled oligonucleotide. Transient transfections with vectors containing mutations of the NF-κB (-499/-493), SP1/3 (-582/-575) or overlapping EGR1/SP1/3 (-597/-587) binding sites reduced luciferase activity by 26%, 61% and 56%, respectively (P<0.05). Thus, NF-κB, SP1/3 and overlapping EGR1/SP1/3 binding sites are critical to expression of the porcine Gnrhr2 gene in ST cells.

Influence of TGFB1 C-509T polymorphism on gastric cancer risk associated with TGF-β1 expression in the gastric mucosa

BACKGROUND

Transforming growth factor-β1 (TGF-β1) has dual roles inhibiting and promoting carcinogenesis. Although many researchers have conducted association studies between TGFB1 C-509T polymorphism and the risk of developing gastric cancer, the results are not uniform.

METHODS

We genotyped 1028 gastric cancer patients and 958 controls by the polymerase chain reaction-restriction fragment length polymorphism method. Immunohistochemistry was performed to assess the expression of TGF-β1 in the cancer and noncancerous tissues of 120 gastric cancer patients. mRNA expression was also measured in noncancerous gastric mucosa by qRT-PCR in the 282 subjects.

RESULTS

The CT genotype in the TGFB1 C-509T polymorphism was associated with an increased risk of gastric cancer development (adjusted OR 1.35, 95 % CI 1.07-1.71, P = 0.013), especially for intestinal-type cancer (adjusted OR 1.43, 95 % CI 1.08-1.90, P = 0.014). More frequent TGF-β1 expression was found in the center of cancer tissue in the TGFB1-509T carrier group than in the others (90.5 % vs. 72.2 %, P = 0.010). T-carriers also presented higher expression level of gastric TGF-β1 mRNA than non T-carriers (median 1.29 vs. 0.80, P = 0.004) when they were infected by H. pylori. Cancer patients showed elevated gastric TGFB1gene expression compared to the control group (median 1.22 vs. 0.89, P = 0.009).

CONCLUSIONS

The carcinogenic effect of TGF-β1 might be associated with increased gastric TGF-β1 expression in subjects with the T allele of TGFB1-509.

Preclinical Study of Novel Gene Silencer Pyrrole-Imidazole Polyamide Targeting Human TGF-β1 Promoter for Hypertrophic Scars in a Common Marmoset Primate Model

We report a preclinical study of a pyrrole-imidazole (PI) polyamide that targets the human transforming growth factor (hTGF)-β1 gene as a novel transcriptional gene silencer in a common marmoset primate model. We designed and then synthesized PI polyamides to target the hTGF-β1 promoter. We examined effects of seven PI polyamides (GB1101-1107) on the expression of hTGF-β1 mRNA stimulated with phorbol 12-myristate 13-acetate (PMA) in human vascular smooth muscle cells. GB1101, GB1105 and GB1106 significantly inhibited hTGF-β1 mRNA expression. We examined GB1101 as a PI polyamide to hTGF-β1 for hypertrophic scars in marmosets in vivo. Injection of GB1101 completely inhibited hypertrophic scar formation at 35 days post-incision and inhibited cellular infiltration, TGF-β1 and vimentin staining, and epidermal thickness. Mismatch polyamide did not affect hypertrophic scarring or histological changes. Epidermis was significantly thinner with GB1101 than with water and mismatch PI polyamides. We developed the PI polyamides for practical ointment medicines for the treatment of hypertrophic scars. FITC-labeled GB1101 with solbase most efficiently distributed in the nuclei of epidermal keratinocytes, completely suppressed hypertropic scarring at 42 days after incision, and considerably inhibited epidermal thickness and vimentin-positive fibroblasts. PI polyamides targeting hTGF-β1 promoter with solbase ointment will be practical medicines for treating hypertrophic scars after surgical operations and skin burns.

Osteopontin mediates an MZF1-TGF-β1-dependent transformation of mesenchymal stem cells into cancer-associated fibroblasts in breast cancer

Interactions between tumor cells and cancer-associated fibroblasts (CAFs) in the tumor microenvironment (TMEN) significantly influence cancer growth and metastasis. Transforming growth factor-β (TGF-β) is known to be a critical mediator of the CAF phenotype, and osteopontin (OPN) expression in tumors is associated with more aggressive phenotypes and poor patient outcomes. The potential link between these two pathways has not been previously addressed. Utilizing in vitro studies using human mesenchymal stem cells (MSCs) and MDA-MB231 (OPN+) and MCF7 (OPN−) human breast cancer cell lines, we demonstrate that OPN induces integrin-dependent MSC expression of TGF-β1 to mediate adoption of the CAF phenotype. This OPN-TGF-β1 pathway requires the transcription factor, myeloid zinc finger 1 (MZF1). In vivo studies with xenotransplant models in NOD-scid mice showed that OPN expression increases cancer growth and metastasis by mediating MSC-to-CAF transformation in a process that is MZF1- and TGF-β1-dependent. We conclude that tumor-derived OPN engenders MSC-to-CAF transformation in the microenvironment to promote tumor growth and metastasis via the OPN-MZF1-TGF-β1 pathway.

Identification and association of the single nucleotide polymorphisms, C-509T, C+466T and T+869C, of the TGF-β1 gene in patients with asthma and their influence on the mRNA expression level of TGF-β1

Transforming growth factor-β1 (TGF-β1) is an important fibrogenic and immunomodulatory cytokine participating in the pathogenesis of a number of illnesses related to the growth, differentiation and migration of cells. It also plays a key role in inflammation, atherosclerosis, vascular inflammation and asthma. The aim of the present study was to evaluate the association between the expression of the TGF-β1 gene and its genetic polymorphisms, and the disease phenotype. The study comprised 173 patients with asthma, as well as 163 healthy volunteers as a control group. The gender profiles of the groups were similar (p=0.8415). Genotyping was performed by polymerase chain reaction (PCR)-high resolution melting (HRM). The results were verified by sequencing. Gene expression was evaluated by RT-PCR. This study evaluated the role and frequency of genetic polymorphisms (C−509T, C+466T and T+869C) of the TGF-β1 gene in the study group (patients with asthma) and the control group (healthy volunteers). The results obtained for the patients and healthy controls were as follows: C−509T single nucleotide polymorphism (SNP) (controls, TT/CT/CC-0.4444/0.5309/0.0247; patients, TT/CT/CC-0.3699/0.6012/0.0289), C+466T SNP (controls, TT/CT/CC-1.000/0.000/0.000; patients, TT/CT/CC-1.000/0.000/0.000) and T+869C SNP (controls, TT/CT/CC-1.000/0.000/0.000; patients, TT/CT/CC-1.000/0.000/0.000). Only the C−509T polymorphism was found to play a significant role in the pathogenesis of asthma, as well as a risk factor in the loss of the clinical control of the disease [TT vs. CC/CT, odds ratio (OR) 2.38; confidence interval (CI) 1.22–4.66; p=0.0103]. A significant difference was noted between the study and control groups with regard to the mRNA expression of TGF-β1 (p=0.0133). A higher level of expression of the TGF-β1 gene correlated with the time of diagnosis of patients over 16 years of age (p=0.0255). This study demonstrates that the C−509T SNP is a significant clinical risk factor for asthma and that the TGF-β1 cytokine contributes to the progression of the illness.

Pin1 induction in the fibrotic liver and its roles in TGF-β1 expression and Smad2/3 phosphorylation

BACKGROUND & AIMS

Therapeutic management of liver fibrosis remains an unsolved clinical problem. Hepatic accumulation of extracellular matrix, mainly collagen, is mediated by the production of transforming growth factor-β1 (TGF-β1) in stellate cells. Pin1, a peptidyl-prolyl isomerase, plays an important pathophysiological role in several diseases, including neurodegeneration and cancer. Herein, we determined whether Pin1 regulates liver fibrogenesis and examined its mechanism of action by focusing on TGF-β1 signalling and hepatic stellate cell (HSC) activation.

METHODS

Pin1 expression was assessed by immunohistochemistry, Western blot or real-time-polymerase chain reaction (RT-PCR) analyses of human and mouse fibrotic liver samples. The role of Pin1 during HSC activation was estimated using Pin1-null mouse embryonic fibroblast (MEF) cells and Pin1-overexpressing LX-2 human hepatic stellate cells.

RESULTS

Pin1 expression was elevated in human and mouse fibrotic liver tissues, and Pin1 inhibition improved dimethylnitrosamine (DMN)-induced liver fibrosis in mice. Pin1 inhibition reduced the mRNA or protein expression of TGF-β1 and α-smooth muscle actin (α-SMA) by DMN treatment. Pin1 knockdown suppressed TGFβ1 gene expression in both LX-2 and MEF cells. Pin1-mediated TGFβ1 gene transcription was controlled by extracellular signal-regulated kinase (ERK)- and phosphoinositide 3-kinase/Akt-mediated activator protein-1 (AP-1) activation. Moreover, TGFβ1-stimulated Smad2/3 phosphorylation and plasminogen activator inhibitor-1 expression were inhibited by Pin1 knockdown.

CONCLUSIONS

Pin1 induction during liver fibrosis is involved in hepatic stellate cell activation, TGFβ1 expression, and TGFβ1-mediated fibrogenesis signalling.

Associations of genetic variants in ADAM33 and TGF-β1 genes with childhood asthma risk

The aim of the present study was to explore the associations of genetic variants in the ADAM33 and TGF-β1 genes with the risk of childhood asthma. A total of 299 asthmatic children and 311 healthy controls were recruited in the hospital-based case-control study. The asthmatic subjects were further divided into mild and severe groups according to disease severity. Single-nucleotide polymorphisms (SNP) at ADAM33 V4, T2, S2 and T1, and TGF-β1 C-509T and T869C were selected and detected with PCR-RFLP. The associations of the SNPs with asthma risk and severity were analyzed. The associations between the haplotypes of ADAM33 and TGF-β1 were also evaluated. Compared with the GG genotype, the GC and CC genotypes at V4 were associated with an increased asthma risk in children and the ORs were 2.92 and 10.56, respectively. Compared with the CC genotype, the CT/TT genotype at C-509T was associated with an increased asthma risk and the OR was 2.26. Subsequent to stratification by asthma severity, compared with the V4 GG genotype, it was found that the CG and CC genotypes were associated with a mild asthma risk and the ORs were 3.00 and 5.99, respectively. The SNP at C-509T (CT/TT vs. CC) was associated with mild asthma (OR=2.34), whereas a marginally significant association was detected between the SNP (CT/TT vs. CC) and severe asthma risk (OR=2.19). The haplotype analysis revealed that, compared with the GGCA haplotype of ADAM33, significant associations of the haplotypes of CGCG, CGGA, GACA, GACG and GAGA with asthma risk were observed, and the ORs were 31.12, 12.24, 4.73, 30.85 and 4.83, respectively. No significant association was detected between the TGF-β1 haplotypes and asthma risk. The genetic variants at V4 and C-509T had the potential to modify the childhood asthma risk and the associations showed no notable difference with the disease severity. Thus, ADAM33 haplotypes provided more useful information in the prediction of asthma risk.

Computational identification of potential transcriptional regulators of TGF-ß1 in human atherosclerotic arteries

TGF-ß is protective in atherosclerosis but deleterious in metastatic cancers. Our aim was to determine whether TGF-ß transcriptional regulation is tissue-specific in early atherosclerosis. The computational methods included 5 steps: (i) from microarray data of human atherosclerotic carotid tissue, to identify the 10 best co-expressed genes with TGFB1 (TGFB1 gene cluster), (ii) to choose the 11 proximal promoters, (iii) to predict the TFBS shared by the promoters, (iv) to identify the common TFs co-expressed with the TGFB1 gene cluster, and (v) to compare the common TFs in the early lesions to those identified in advanced atherosclerotic lesions and in various cancers. Our results show that EGR1, SP1 and KLF6 could be responsible for TGFB1 basal expression, KLF6 appearing specific to atherosclerotic lesions. Among the TFs co-expressed with the gene cluster, transcriptional activators (SLC2A4RG, MAZ) and repressors (ZBTB7A, PATZ1, ZNF263) could be involved in the fine-tuning of TGFB1 expression in atherosclerosis.

TGF-beta1 gene polymorphism in association with diabetic retinopathy susceptibility: a systematic review and meta-analysis

Background

Transforming growth factor-beta (TGF-β1) gene has been regarded as an important mechanism in angiogenesis, endothelial cell proliferation, adhesion,and the deposition of extracellular matrix. The TGF-β1 gene may be involved in the development of diabetic retinopathy (DR) through disrupting angiogenesis. However, studies investigating the relationship between −509C/T and +869T/C(L10P) polymorphisms and DR yielded contradictory and inconclusive outcomes. In order to realize these ambiguous findings, a meta-analysis was performed to assess the association between the TGF-β1 gene polymorphisms and susceptibility to DR.

Methodology/Principal Findings

We conducted a search of all English reports on studies for the association between the TGF-β1 gene polymorphisms and susceptibility to DR using Medline, the Cochrane Library, EMbase, Web of Science, Google (scholar), and all Chinese reports were identified manually and on-line using CBMDisc, Chongqing VIP database, and CNKI database. The strict selection criteria and exclusion criteria were determined, and odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations. The fixed or random effect model was selected based on the heterogeneity test among studies. Publication bias was estimated using Begg's funnel plots and Egger's regression test.

Results

A total of three studies were included in the meta-analysis and all included studies analyzed patients with type 2 diabetes. For +869T/C(L10P) polymorphism, significant association was observed in an allele model (L versus P: OR = 1.34, 95%CI = 1.03–1.73) and the recessive model (LL versus LP+PP: OR = 1.70, 95%CI = 1.13–2.56). As regards −509C/T polymorphism, no obvious associations were found for all genetic models.

Conclusions

This meta-analysis suggested that the +869T/C(L10P) polymorphism in TGFβ1 gene would be a potential protect factor for DR. However, the −509C/T polymorphism is not associated with DR.

Lack of Association Between Transforming Growth Factor Beta 1 -509C/T and +915G/C Polymorphisms and Chronic Hepatitis B in Iranian Patients

BACKGROUND

Chronic hepatitis B is one of the world's major health concerns [corrected]. The etiological agent of this infection is hepatitis B virus (HBV), which can evade the immune system response. Transforming growth factor beta 1 (TGF-β1) can act against HBV by suppressing the viral replication. The TGF-β1 also plays an important role in preventing liver damage in chronically HBV infected patients.

OBJECTIVES

In this study, the association of TGF-β1 +915G/C and -509C/T gene polymorphisms with chronic hepatitis B was evaluated in Iranian patients.

MATERIALS AND METHODS

A population-based case-control study was conducted in Taleghani Hospital, Tehran. A number of 220 patients with chronic hepatitis B and the same number of healthy control subjects were designated the case and the control groups. The PCR-Restriction Fragment Length Polymorphism Method (PCR-RFLP) method was used for genotyping both polymorphisms. Ten percent of the control samples were sequenced to confirm the results.

RESULTS

No statically significant differences in genotype distribution and allele frequency were observed for both polymorphisms between healthy controls and patients with chronic hepatitis B.

CONCLUSIONS

There was no association between TGF-β1 -509C/T and +915G/C polymorphisms with chronic hepatitis B and it seems that these changes do not play a significant role in increasing the risk of chronic infection in Iranian patients [corrected].

Genetic association and gene expression profiles of TGFB1 and the contribution of TGFB1 to otosclerosis susceptibility

Otosclerosis (OTSC) is a common form of acquired hearing loss resulting from disturbed bone remodeling in the otic capsule of the middle ear. Transforming growth factor-beta1 (TGFB1) produced by osteoblasts is the most abundant growth factor in human bone. Previous studies have shown the contribution of single-nucleotide polymorphisms (SNPs) in TGFB1 toward the risk of developing OTSC in some ethnic populations. The present study was aimed at investigating the genetic association and expression profiles of TGFB1 in OTSC patients. Two SNPs (c.-800G > A and c.-509C > T) in the promoter region and three SNPs (c.29T > C, c.74G > C, and c.788C > T) in the coding region were genotyped in 170 cases and 170 controls. The genetic association analysis revealed the significant association between c.-509C > T (p = 0.0067; odds ratio [OR] = 1.562; 95% confidence interval [CI], 1.140-2.139) and OTSC. The increased minor allele "T" frequency in cases (0.42) compared to controls (0.31) indicates its possible role in the etiology of the disease. The minor allele frequencies for the SNPs c.-800G > A, c.29T > C, and c.74G >C were similar among the cases (0.04, 0.47, and 0.08, respectively) and controls (0.05, 0.42, 0.07, respectively). We found that c.788C > T was monomorphic in this population. Interestingly, a four-locus haplotype (G-T-T-G) from these SNPs was found to be significantly associated with OTSC (p = 0.0077). We identified a de novo heterozygous mutation c.-832G > A in the promoter region of TGFB1 in 1 patient. In a secondary analysis, we investigated the possibility of abnormal TGFB1 expression and irregular bone growth in OTSC by expression analysis of TGFB1 mRNA in disease tissue compared to control. We found relatively increased expression of TGFB1 mRNA in the stapes tissues of cases compared to controls (p = 0.0057). In conclusion, this study identified a risk variant c.-509C > T and a risk haplotype G-T-T-G in the TGFB1 gene that contribute toward the susceptibility to OTSC.

In vivo, in vitro, and in silico studies suggest a conserved immune module that regulates malaria parasite transmission from mammals to mosquitoes

Human malaria can be caused by the parasite Plasmodium falciparum that is transmitted by female Anopheles mosquitoes. "Immunological crosstalk" between the mammalian and anopheline hosts for Plasmodium functions to control parasite numbers. Key to this process is the mammalian cytokine transforming growth factor-β1 (TGF-β1). In mammals, TGF-β1 regulates inducible nitric oxide (NO) synthase (iNOS) both positively and negatively. In some settings, high levels of NO activate latent TGF-β1, which in turn suppresses iNOS expression. In the mosquito, ingested TGF-β1 induces A. stephensi NOS (AsNOS), which limits parasite development and which in turn is suppressed by activation of the mosquito homolog of the mitogen-activated protein kinases MEK and ERK. Computational models linking TGF-β1, AsNOS, and MEK/ERK were developed to provide insights into this complex biology. An initial Boolean model suggested that, as occurs in mammalian cells, MEK/ERK and AsNOS would oscillate upon ingestion of TGF-β1. An ordinary differential equation (ODE) model further supported the hypothesis of TGF-β1-induced multiphasic behavior of MEK/ERK and AsNOS. To achieve this multiphasic behavior, the ODE model was predicated on the presence of constant levels of TGF-β1 in the mosquito midgut. Ingested TGF-β1, however, did not exhibit this behavior. Accordingly, we hypothesized and experimentally verified that ingested TGF-β1 induces the expression of the endogenous mosquito TGF-β superfamily ligand As60A. Computational simulation of these complex, cross-species interactions suggested that TGF-β1 and NO-mediated induction of As60A expression together may act to maintain multiphasic AsNOS expression via MEK/ERK-dependent signaling. We hypothesize that multiphasic behavior as represented in this model allows the mosquito to balance the conflicting demands of parasite killing and metabolic homeostasis in the face of damaging inflammation.

Activation of TGF-β1 promoter by hepatitis C virus-induced AP-1 and Sp1: role of TGF-β1 in hepatic stellate cell activation and invasion

Our previous studies have shown the induction and maturation of transforming growth factor-beta 1 (TGF-β1) in HCV-infected human hepatoma cells. In this study, we have investigated the molecular mechanism of TGF-β1 gene expression in response to HCV infection. We demonstrate that HCV-induced transcription factors AP-1, Sp1, NF-κB and STAT-3 are involved in TGF-β1 gene expression. Using chromatin immunoprecipitation (ChIP) assay, we further show that AP-1 and Sp1 interact with TGF-b1 promoter in vivo in HCV-infected cells. In addition, we demonstrate that HCV-induced TGF-β1 gene expression is mediated by the activation of cellular kinases such as p38 MAPK, Src, JNK, and MEK1/2. Next, we determined the role of secreted bioactive TGF-β1 in human hepatic stellate cells (HSCs) activation and invasion. Using siRNA approach, we show that HCV-induced bioactive TGF-β1 is critical for the induction of alpha smooth muscle actin (α-SMA) and type 1 collagen, the markers of HSCs activation and proliferation. We further demonstrate the potential role of HCV-induced bioactive TGF-β1 in HSCs invasion/cell migration using a transwell Boyden chamber. Our results also suggest the role of HCV-induced TGF-β1 in HCV replication and release. Collectively, these observations provide insight into the mechanism of TGF-β1 promoter activation, as well as HSCs activation and invasion, which likely manifests in liver fibrosis associated with HCV infection.