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The transforming growth factor beta (TGF-β) signaling pathway is a tumor-suppressor pathway that is commonly inactivated in colorectal cancer (CRC). The inactivation of TGFBR2 is the most common genetic event affecting the TGF-β signaling pathway. However, the mechanism by which cancer cells downregulate TGFBR2 is unclear. In this study, we found that the TGFBR2 protein levels were consistently upregulated in CRC tissues, whereas its mRNA levels varied in these tissues, suggesting that a post-transcriptional mechanism is involved in the regulation of TGFBR2. Because microRNAs (miRNAs) are powerful post-transcriptional regulators of gene expression, we performed bioinformatic analyses to search for miRNAs that potentially target TGFBR2. We identified the specific targeting site of miR-135b in the 3’-untranslated region (3’-UTR) of TGFBR2. We further identified an inverse correlation between the levels of miR-135b and TGFBR2 protein, but not mRNA, in CRC tissue samples. By overexpressing or silencing miR-135b in CRC cells, we experimentally validated that miR-135b directly binds to the 3’-UTR of the TGFBR2 transcript and regulates TGFBR2 expression. Furthermore, the biological consequences of the targeting of TGFBR2 by miR-135b were examined using in vitro cell proliferation and apoptosis assays. We demonstrated that miR-135b exerted a tumor-promoting effect by inducing the proliferation and inhibiting the apoptosis of CRC cells via the negative regulation of TGFBR2 expression. Taken together, our findings provide the first evidence supporting the role of miR-135b as an oncogene in CRC via the inhibition of TGFBR2 translation. [ABSTRACT FROM AUTHOR]

The levels and intracellular localization of wild-type transforming growth factor β superfamily (TGFβ-SF) receptors are tightly regulated by endocytic trafficking, shedding and degradation. In contrast, a main regulatory mechanism of mutation-bearing receptors involves their intracellular retention. Anti-Mullerian hormone receptor II (AMHRII, also known as AMHR2) is the type-II receptor for anti-Mullerian hormone (AMH), a TGFβ-SF ligand that mediates Mullerian duct regression in males. Here, we studied AMHRII processing and identified novel mechanisms of its constitutive negative regulation. Immunoblot analysis revealed that a significant portion of AMHRII was missing most of its extracellular domain (ECD) and, although glycosylated, was unfolded and retained in the endoplasmic reticulum. Exogenous expression of AMHRII, but not of type-II TGF-b receptor (TβRII, also known as TGFR2), resulted in its disulfide-bond-mediated homo-oligomerization and intracellular retention, and in a decrease in its AMH-binding capacity. At the plasma membrane, AMHRII differed from TβRII, forming high levels of non-covalent homomeric complexes, which exhibited a clustered distribution and restricted lateral mobility. This study identifies novel mechanisms of negative regulation of a type-II TGF-β receptor through cleavage, intracellular retention and/or promiscuous disulfide-bond mediated homo-oligomerization. [ABSTRACT FROM AUTHOR]

The members of transforming growth factor β family (TGF-β) are multifunctional proteins but their main role is to control cell proliferation and differentiation. Polypeptides of TGF-β family function by binding to two related, functionally distinct transmembrane receptor kinases, first to the type II (TβR II) followed by type I receptor (TβR I). The paper describes, in details, the stability of wt-ec-TβR II under different conditions. The stability of wt-ec-TβR II was observed at different pH and salt concentration using fluorescence spectroscopy. Stability of ec-TβR II decreases with decrease in pH. Interestingly, the addition of salt increases the stability of the TβRII at pH 5.0 as observed for halophiles. Computational analysis using DELPHI suggests that this is probably due to the decrease in repulsion between negatively charged residues at surface on the addition of salt. This is further confirmed by the change in the stability of receptor on mutation of some of the residues (D32A) at surface. [ABSTRACT FROM AUTHOR]

Angiotensin-(1–7) (Ang-(1–7))/AT 7 -Mas receptor axis is an alternative pathway within the renin–angiotensin system (RAS) that generally opposes the actions of Ang II/AT 1 receptor pathway. Advanced glycated end product (AGEs) including glucose- and methylglyoxal-modified albumin (MGA) may contribute to the development and progression of diabetic nephropathy in part through activation of the Ang II/AT 1 receptor system; however, the influence of AGE on the Ang-(1–7) arm of the RAS within the kidney is unclear. The present study assessed the impact of AGE on the Ang-(1–7) axis in NRK-52E renal epithelial cells. MGA exposure for 48 h significantly reduced the intracellular levels of Ang-(1–7) approximately 50%; however, Ang I or Ang II expression was not altered. The reduced cellular content of Ang-(1–7) was associated with increased metabolism of the peptide to the inactive metabolite Ang-(1–4) [MGA: 175 ± 9 vs. Control: 115 ± 11 fmol/min/mg protein, p < 0.05, n = 3] but no change in the processing of Ang I to Ang-(1–7). Treatment with Ang-(1–7) reversed MGA-induced cellular hypertrophy and myofibroblast transition evidenced by reduced immunostaining and protein expression of α-smooth muscle actin (α-SMA) [0.4 ± 0.1 vs. 1.0 ± 0.1, respectively, n = 3, p < 0.05]. Ang-(1–7) abolished AGE-induced activation of the MAP kinase ERK1/2 to a similar extent as the TGF-β receptor kinase inhibitor SB58059; however, Ang-(1–7) did not attenuate the MGA-stimulated release of TGF-β. The AT 7 -Mas receptor antagonist D-Ala 7 -Ang-(1–7) abolished the inhibitory actions of Ang-(1–7). In contrast, AT 1 receptor antagonist losartan did not attenuate the MGA-induced effects. We conclude that Ang-(1–7) may provide an additional therapeutic approach to the conventional RAS blockade regimen to attenuate AGE-dependent renal injury. [ABSTRACT FROM AUTHOR]

Background The pathogenesis of nonalcoholic fatty liver disease (NAFLD) has been attributed to increased systemic inflammation and insulin resistance mediated by visceral adipose tissue (VAT), although the exact mechanisms are undefined. Exosomes are membrane-derived vesicles containing messenger RNA, microRNA, and proteins, which have been implicated in cancer, neurodegenerative, and autoimmune diseases, which we postulated may be involved in obesity-related diseases. We isolated exosomes from VAT, characterized their content, and identified their potential targets. Targets included the transforming growth factor beta (TGF-β) pathway, which has been linked to NAFLD. We hypothesized that adipocyte exosomes would integrate into HepG2 and hepatic stellate cell lines and cause dysregulation of the TGF-β pathway. Methods Exosomes from VAT from obese and lean patients were isolated and fluorescently labeled, then applied to cultured hepatic cell lines. After incubation, culture slides were imaged to detect exosome uptake. In separate experiments, exosomes were applied to cultured cells and incubated 48-h. Gene expression of TGF-β pathway mediators was analyzed by polymerase chain reaction, and compared with cells, which were not exposed to exosomes. Results Fluorescent-labeled exosomes integrated into both cell types and deposited in a perinuclear distribution. Exosome exposure caused increased tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and integrin αvβ-5 expression and decreased matrix metalloproteinase-7 and plasminogen activator inhibitor-1 expression in to HepG2 cells and increased expression of TIMP-1, TIMP-4, Smad-3, integrins αvβ-5 and αvβ-8, and matrix metalloproteinase-9 in hepatic stellate cells. Conclusions Exosomes from VAT integrate into liver cells and induce dysregulation of TGF-β pathway members in vitro and offers an intriguing possibility for the pathogenesis of NAFLD. [ABSTRACT FROM AUTHOR]

Summary Seizures have been shown to upregulate the expression of numerous extracellular matrix molecules. Tenascin C (TNC) is an extracellular matrix protein involved in several physiological roles and in pathological conditions. Though TNC upregulation has been described after excitotoxins injection, to date there is no research work on the signal transduction pathway(s) participating in TNC protein overproduction. The aim of this study was to evaluate the role of TGF-β signaling pathway on TNC upregulation. In this study, we used male rats, which were injected with saline or pilocarpine to induce status epilepticus (SE) and killed 24 h, 3 and 7 days after pilocarpine administration. For evaluating biochemical changes, we measured protein content of TNC, TGF-β1 and phospho-Smad2/3 for localization of TNC in coronal brain hippocampus at 24 h, 3 and 7 days after pilocarpine-caused SE. We found a significant increase of TNC protein content in hippocampal homogenates after 1, 3, and 7 days of pilocarpine-caused SE, together with an enhancement of TNC immunoreactivity in several hippocampal layers and the dentate gyrus field where more dramatic changes occurred. We also observed a significant enhancement of protein content of both the TGF-β1 and the critical downstream transduction effector phospho-Smad2/3 throughout the chronic exposure. Interestingly, animals injected with SB-431542, a TGF-β-type I receptor inhibitor, decreased TNC content in cytosolic fraction and diminished phospho-Smad2/3 content in both cytoplasmic and nuclear fraction compared with pilocarpine vehicle-injected. These findings suggest the participation of TGF-β signaling pathway on upregulation of TNC which in turn support the idea that misregulation of this signaling pathway produces changes that may contribute to disease. [ABSTRACT FROM AUTHOR]

Apoptosis is thought to contribute to the progression of periodontitis. It has been suggested that the apoptosis of epithelial cells may contribute to the loss of epithelial barrier function. Smad2, a downstream signaling molecule of TGF-β receptors (TGF-βRs), is critically involved in apoptosis in several cell types. However, the relationship between smad2 and bacteria-induced apoptosis has not yet been elucidated. It is possible that the regulation of apoptosis induced by periodontopathic bacteria may lead to novel preventive therapies for periodontitis. Therefore, in the present study, we investigated the involvement of smad2 phosphorylation in apoptosis of human gingival epithelial cells induced by Aggregatibacter actinomycetemcomitans (Aa). Aa apparently induced the phosphorylation of smad2 in primary human gingival epithelial cells (HGECs) or the human gingival epithelial cell line, OBA9 cells. In addition, Aa induced phosphorylation of the serine residue of the TGF-β type I receptor (TGF-βRI) in OBA9 cells. SB431542 (a TGF-βRI inhibitor) and siRNA transfection for TGF-βRI, which reduced both TGF-βRI mRNA and protein levels, markedly attenuated the Aa-induced phosphorylation of smad2. Furthermore, the disruption of TGF-βRI signaling cascade by SB431542 and siRNA transfection for TGF-βRI abrogated the activation of cleaved caspase-3 expression and repressed apoptosis in OBA9 cells treated with Aa. Thus, Aa induced apoptosis in gingival epithelial cells by activating the TGF-βRI-smad2-caspase-3 signaling pathway. The results of the present study may suggest that the periodontopathic bacteria, Aa, activates the TGF-βR/smad2 signaling pathway in human gingival epithelial cells and induces apoptosis in epithelial cells, which may lead to new therapeutic strategies that modulate the initiation of periodontitis. [ABSTRACT FROM PUBLISHER]

Activation of hepatic stellate cells (HSCs) is a key event in the initiation of liver fibrosis, characterized by enhanced extracellular matrix production and altered degradation. Activation of HSCs can be modulated by cytokines produced by immune cells. Recent reports have implicated the proinflammatory cytokine IL-17A in liver fibrosis progression. We hypothesized that IL-17A may enhance activation of HSCs and induction of the fibrogenic signals in these cells. The human HSC line LX2 and primary human HSCs were stimulated with increasing doses of IL-17A and compared with TGF-β- and PBS-treated cells as positive and negative controls, respectively. IL-17A alone did not induce activation of HSCs. However, IL-17A sensitized HSCs to the action of suboptimal doses of TGF-β as confirmed by strong induction of α-smooth muscle actin, collagen type I (COL1A1), and tissue inhibitor of matrix metalloproteinase I gene expression and protein production. IL-17A specifically upregulated the cell surface expression of TGF-βRII following stimulation. Pretreatment of HSCs with IL-17A enhanced signaling through TGF-βRII as observed by increased phosphorylation of SMAD2/3 in response to stimulation with suboptimal doses of TGF-β. This enhanced TGF-β response of HSCs induced by IL-17A was JNK-dependent. Our results suggest a novel profibrotic function for IL-17A by enhancing the response of HSCs to TGF-β through activation of the JNK pathway. IL-17A acts through upregulation and stabilization of TGF-βRII, leading to increased SMAD2/3 signaling. These findings represent a novel example of cooperative signaling between an immune cytokine and a fibrogenic receptor. [ABSTRACT FROM AUTHOR]

DNA damage found in prostate cancer-associated fibroblasts (CAF) promotes tumor progression. In the absence of somatic mutations in CAF, epigenetic changes dictate how stromal coevolution is mediated in tumors. Seventy percent of prostate cancer patients lose expression of transforming growth factor-beta type II receptor (TGFBR2) in the stromal compartment (n=77, P-value=0.0001), similar to the rate of glutathione S-transferase P1 (GSTP1) silencing. Xenografting of human prostate cancer epithelia, LNCaP, resulted in the epigenetic Tgfbr2 silencing of host mouse prostatic fibroblasts. Stromal Tgfbr2 promoter hypermethylation, initiated by LNCaP cells, was found to be dependent on interleukin 6 expression, based on neutralizing antibody studies. We further found that pharmacologic and transgenic knockout of TGF-β responsiveness in prostatic fibroblasts induced Gstp1 promoter methylation. It is known that TGF-β promotes DNA stability, however, the mechanism is not well understood. Both prostatic human CAF and mouse transgenic knockout of Tgbr2 had elevated DNA methyltransferase I (DNMT1) activity and histone H3 lysine 9 trimethylation (H3K9me3) to suggest greater promoter methylation. Interestingly, the conditional knockout of Tgfbr2 in mouse prostatic fibroblasts, in modeling epigenetic silencing of Tgfbr2, had greater epigenetic gene silencing of multiple DNA damage repair and oxidative stress response genes, based on promoter methylation array analysis. Homologous gene silencing was validated by reverse transcriptase (RT)-PCR in mouse and human prostatic CAF. Not surprisingly, DNA damage repair gene silencing in the prostatic stromal cells corresponded with the presence of DNA damage. Restoring the expression of the epigenetically silenced genes in wild-type fibroblasts with radiation-induced DNA damage reduced tumor progression. Tumor progression was inhibited even when epigenetic silencing was reversed in the Tgfbr2-knockout prostatic fibroblasts. Taken together, fibroblastic epigenetic changes causative of DNA damage, initiated by association with cancer epithelia, is a dominant mediator of tumor progression over TGF-β responsiveness. [ABSTRACT FROM AUTHOR]

Possible involvement of MEK mitogen-activated protein kinase and TGF-β receptor in the processes of regeneration and morphogenesis in freshwater planarian flatworms Schmidtea mediterranea was studied using a pharmacological inhibitor analysis. It was found that pharmacological inhibitors of these kinases significantly inhibit the regeneration of the head end of the animals and that this effect is realized due to inhibition of proliferative activity of neoblasts, planarian stem cells. It is shown that that the inhibition of the studied protein kinases in regenerating planarians markedly disturbs stem cell differentiation and morphogenesis. [ABSTRACT FROM AUTHOR]

Transforming growth factor-βs (TGF-βs) regulate cellular proliferation, differentiation, and survival. TGF-βs bind to type I (TGF-βRI) and II receptors (TGF-βRII), which are transmembrane kinase receptors, and an accessory type III receptor (TGF-βRIII). TGF-β may utilize another type I receptor, activin-like kinase receptor (Alk1). TGF-β is neuroprotective in the middle cerebral artery occlusion (MCAO) model of stroke. Recently, we reported the expression pattern of TGF-β1-3 after MCAO. To establish how TGF-βs exert their actions following MCAO, the present study describes the induction of TGF-βRI, RII, RIII and Alk1 at 24 h, 72 h and 1 mo after transient 1 h MCAO as well as following 24 h permanent MCAO using in situ hybridization histochemistry. In intact brain, only TGF-βRI had significant expression: neurons in cortical layer IV contained TGF-βRI. At 24 h after the occlusion, no TGF-β receptors showed induction. At 72 h following MCAO, all four types of TGF-β receptors were induced in the infarct area, while TGF-βRI and RII also appeared in the penumbra. Most cells with elevated TGF-βRI mRNA levels were microglia. TGF-βRII co-localized with both microglial and endothelial markers while TGF-βRIII and Alk1 were present predominantly in endothels. All four TGF-β receptors were induced within the lesion 1 mo after the occlusion. In particular, TGF-βRIII was further induced as compared to 72 h after MCAO. At this time point, TGF-βRIII signal was predominantly not associated with blood vessels suggesting its microglial location. These data suggest that TGF-β receptors are induced after MCAO in a timely and spatially regulated fashion. TGF-β receptor expression is preceded by increased TGF-β expression. TGF-βRI and RII are likely to be co-expressed in microglial cells while Alk1, TGF-βRII, and RIII in endothels within the infarct where TGF-β1 may be their ligand. At later time points, TGF-βRIII may also appear in glial cells to potentially affect signal transduction via TGF-βRI and RII. [ABSTRACT FROM AUTHOR]

Objectives: Emdogain, containing an extract of fetal porcine enamel matrix proteins, is a potent stimulator of in vitro osteoclastogenesis. The underlying molecular mechanisms are, however, unclear. Material and methods: Here, we have addressed the role of transforming growth factor-beta receptor type 1 (TGF-βRI) kinase activity on osteoclastogenesis in murine bone marrow cultures. Results: Inhibition of TGF-βRI kinase activity with SB431542 abolished the effect of Emdogain on osteoclastogenesis induced by receptor activator of nuclear factor kappa-B ligand or tumor necrosis factor-alpha. SB431542 also suppressed the Emdogain-mediated increase of OSCAR, a co-stimulatory protein, and dendritic cell-specific transmembrane protein and Atp6v0d2, the latter two being involved in cell fusion. Similar to transforming growth factor-beta1 (TGF-β), Emdogain could not compensate for the inhibition of IL-4 and IFNγ on osteoclast formation. When using the murine macrophage cell line RAW246.7, SB431542 and the smad-3 inhibitor SIS3 blocked Emdogain-stimulated expression of the transcription factor NFATc1. Conclusions: Taken together, the data suggest that TGF-βRI kinase activity is necessary to mediate in vitro effects of Emdogain on osteoclastogenesis. Clinical relevance: Based on these in vitro data, we can speculate that at least part of the clinical effects of Emdogain on osteoclastogenesis is mediated via TGF-β signaling. [ABSTRACT FROM AUTHOR]

Abstract: A series of 4-([1,2,4]triazolo[1,5-a]pyridin-6-yl)-5(3)-(6-methylpyridin-2-yl)imidazoles and -pyrazoles 14a–c, 15a–c, 16a, 16b, 19a–d, 21a, and 21b has been synthesized and evaluated for their ALK5 inhibitory activity in an enzyme assay and in a cell-based luciferase reporter assay. Among them, the pyrazole derivative 21b inhibited ALK5 phosphorylation with an IC50 value of 0.018μM and showed 95% inhibition at 0.03μM in a luciferase reporter assay using HaCaT cells permanently transfected with p3TP-luc reporter construct. The 21b showed a high selectivity index of 284 against p38α MAP kinase. The binding pose of 21b generated by docking analysis reveals that it fits well into the ATP binding cavity of ALK5 by forming several hydrogen bond interactions. [Copyright &y& Elsevier]

Transforming growth factor ( TGF)-β, type I receptor ( TβRI) and c- Jun N-terminal kinases ( JNK) phosphorylate Smad3 differentially to create 2 isoforms phosphorylated (p) at the COOH-terminus ( C) or at the linker region ( L) and regulate hepatocytic fibrocarcinogenesis. This study aimed to compare the differences between how hepatitis B virus ( HBV) infection affected hepatocytic Smad3 phosphorylated isoforms before and after anti-viral therapy. To clarify the relationship between Smad3 phosphorylation and liver disease progression, we studied 10 random patients in each stage of HBV-related fibrotic liver disease ( F1-4) and also 10 patients with HBV-associated HCC. To examine changes in phosphorylated Smad3 signalling before and after anti- HBV therapies, we chose 27 patients with chronic hepatitis B who underwent baseline and follow-up biopsies at 52 weeks from the start of nucleoside analogue treatments ( Lamivudine 100 mg daily or Telbivudine 600 mg daily). Fibrosis stage, inflammatory activity and phosphorylated Smad3 positivity in the paired biopsy samples were compared. Hepatocytic p Smad3 C signalling shifted to fibrocarcinogenic p Smad3 L signalling as the livers progressed from chronic hepatitis B infection to HCC. After nucleoside analogue treatment, serum alanine aminotransferase ( ALT) and HBV- DNA levels in 27 patients with HBV-related chronic liver diseases were decreased dramatically. Decrease in HBV- DNA restored p Smad3 C signalling in hepatocytes, while eliminating prior fibrocarcinogenic p Smad3 L signalling. Oral nucleoside analogue therapies can suppress fibrosis and reduce HCC incidence by successfully reversing phosphorylated Smad3 signalling; even liver disease progressed to cirrhosis in chronic hepatitis B patients. [ABSTRACT FROM AUTHOR]

MicroRNAs have added a new dimension to our understanding of tumorigenesis and associated processes like epithelial-to-mesenchymal transition (EMT). Here, we show that miR-375 is elevated in epithelial-like breast cancer cells, and ectopic miR-375 expression suppresses EMT in mesenchymal-like breast cancer cells. We identified short stature homeobox 2 (SHOX2) as a miR-375 target, and miR-375--mediated suppression in EMT was reversed by forced SHOX2 expression. Ectopic SHOX2 expression can induce EMT in epithelial-like breast cancer cells, whereas SHOX2 knockdown diminishes EMT traits in mesenchymal-like breast cancer cells, demonstrating SHOX2 as an EMT inducer. We show that SHOX2 acts as a transcription factor to upregulate transforming growth factor β receptor I (TβR-I) expression, and TβR-I inhibitor LY364947 abolishes EMT elicited by ectopic SHOX2 expression, suggesting that transforming growth factor β signaling is essential for SHOX2-induced EMT. Manipulating SHOX2 abundance in breast cancer cells impact in vitro invasion and in vivo dissemination. Analysis of breast tumor microarray database revealed that high SHOX2 expression significantly correlates with poor patient survival. Our study supports a critical role of SHOX2 in breast tumorigenicity. [ABSTRACT FROM AUTHOR]

Renal fibrosis results from excessive accumulation of extracellular matrix mainly driven by transforming growth factor-β1 (TGF-β1). Certain microRNAs have been implicated in this disease, and here we examine the role of let-7b. Rat proximal tubular epithelial cells (NRK52E) were treated with TGF-β1 for 3 days to assess the expression of markers of fibrosis and let-7b. These factors were also assessed in two mouse models representing early and more advanced diabetic nephropathy and in the non-diabetic adenine-induced renal fibrosis model. TGF-β1 downregulated the expression of let-7b and induced fibrogenesis in NRK52E cells. Ectopic expression of let-7b repressed TGF-β1 receptor 1 (TGFBR1) expression directly by targeting the two let-7b binding sites in the 3′-untranslated region of that gene, reduced expression of extracellular matrix proteins, decreased SMAD3 activity, and attenuated the profibrotic effects of TGF-β1. Knockdown of let-7b elevated TGFBR1 expression and mimicked some of the profibrotic effects of TGF-β1. Consistent with these observations, let-7b expression was also reduced in models of both diabetic and non-diabetic renal fibrosis with the upregulation of TGFBR1. Thus, let-7b microRNA represents a potential new target for the treatment of renal fibrosis in diabetic and non-diabetic nephropathy. [ABSTRACT FROM AUTHOR]

Abstract: Loeys–Dietz syndrome (LDS) is a connective tissue disorder caused by monoallelic mutations in TGFBR1 and TGFBR2, which encode for subunits of the transforming growth factor beta (TGFβ) receptor. Affected patients are identified by vascular aneurysms with tortuosity and distinct morphological presentations similar to Marfan syndrome; however, an additional predisposition towards asthma and allergy has recently been found. We describe two patients with a novel missense mutation in TGFBR1 presenting with highly elevated levels of IgE and severe eczema similar to autosomal-dominant Hyper-IgE syndrome (HIES). Mild allergic manifestations with normal up to moderately increased IgE were observed in 3 out of 6 additional LDS patients. A comparison of this cohort with 4 HIES patients illustrates the significant overlap of both syndromes including eczema and elevated IgE as well as skeletal and connective tissue manifestations. [Copyright &y& Elsevier]

MicroRNA-208a (mir-208a) is essential for cardiac hypertrophy and fibrosis. Endoglin, a co-receptor of transforming growth factor-β is also essential for cardiac fibrosis. Endoglin has been shown to be a target of mir-208a in the in vitro mechanical stress model. Volume overload can lead to heart failure and cardiac fibrosis. The role of mir-208a and endoglin in volume overload heart failure is well known. We sought to investigate the mechanism of regulation of mir-208a and endoglin in volume overload-induced heart failure. Aorta-caval (AV) shunt was performed in adult Sprague-Dawley rats to induce volume overload. Heart weight and heart weight/body weight ratio significantly increased in AV shunt animals. AV shunt significantly increased left ventricular end-diastolic dimension as compared to sham group. Mir-208a was significantly induced by AV shunt from 3 to 14 days. Endoglin, myosin heavy chain-β and brain natriuretic peptide were significantly induced by AV shunt from 3 to 14 days. Overexpression of mir-208a in the sham group without AV shunt significantly increased endoglin expression similar to the AV shunt group. Antagomir-208a attenuated the endoglin expression induced by AV shunt. Pretreatment with atorvastatin also attenuated the endoglin expression induced by AV shunt. AV shunt significantly increased myocardial fibrosis as compared to sham group. Overexpression of mir-208a in the sham group significantly increased myocardial fibrosis. Antagomir-208a and atorvastatin significantly attenuated the myocardial fibrosis induced by AV shunt. In conclusion, mir-208a increased endoglin expression to induce myocardial fibrosis in volume overloaded heart failure. Treatment with atorvastatin can attenuate the myocardial fibrosis induced by volume overload through inhibition of endoglin expression. [ABSTRACT FROM AUTHOR]

Highlights: [•] TGF-β receptor and PI3K/AKT pathways show diverse mechanisms of crosstalk. [•] PI3K/AKT activation antagonizes the TGF-β/SMAD-induced cytostatic response. [•] PI3K/AKT activation can convert tumor-suppressing into tumor promoting TGF-β function. [•] TGF-β receptor and PI3K/AKT pathways cooperate in cancer progression. [Copyright &y& Elsevier]

Abstract: In our previous study, a dominant sequence called aptamer S58 antagonized TGF-β-induced myofibroblast transdifferentiation in human Tenon's capsule fibroblasts (HTFs) through sealing the targeting site of TGF-β receptor II (TβR II). However, rapid degradation by ubiquitous nucleases limited the aptamer's efficacy. Chitosan-nanoparticles (CS-NP) are good drug carriers. Herein we synthesises novel chitosan nanoparticle–aptamer S58 complexes called CS(S58)-NP in order to preserve and prolong S58's efficacy. We synthesised CS(S58)-NP at various molar ratios of CS-NP to S58 using an ionic gelation method. Then, the properties of the CS(S58)-NP including particle size, zeta potential, protection capacity, slow-release effect and cytotoxicity were studied. The targeting effect of the CS(S58)-NP was also studied. CS(S58)-NP at molar ratios of 20 and 30 showed high aptamer encapsulation efficiency, powerful aptamer protection, stable sustained-release ability and low cytotoxicity. FITC-labelled CS(S58)-NP could successfully bind to TβR II. As a result, TGF-β-induced cell proliferation and α-SMA expression were both inhibited. Furthermore, the CS(S58)-NP could inhibit TGF-β-induced α-SMA expression for a longer time than naked S58, even in serum. This research applied CS-NP as the aptamer carrier. The research results demonstrate that CS-NP are potentially able to preserve and prolong aptamer S58's efficacy. This study reveals that the use of CS-NP is promising for aptamer delivery and CS(S58)-NP can be a potential anti-scarring therapeutic approach after glaucoma filtration surgery. [Copyright &y& Elsevier]

Objective: To analyze the differentially expressed genes and identify featured biomarkers from prostatic carcinoma. Methods: The software "Significance Analysis of Microarray" (SAM) was used to identify the differentially coexpressed genes (DCGs). The DCGs existed in two datasets were analyzed by GO (Gene Ontology) functional annotation. Results: A total of 389 DCGs were obtained. By GO analysis, we found these DCGs were closely related with the acinus development, TGF-ß receptor and signal transduction pathways. Furthermore, five featured biomarkers were discovered by interaction analysis. Conclusion: These important signal pathways and oncogenes may provide potential therapeutic targets for prostatic carcinoma. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Fibroblasts are key components of the tumor microenvironment. We clarified the role of transforming growth factor (TGF)-β and interleukin (IL)-6 in the interaction between fibroblasts and non-small-cell lung cancer (NSCLC) cells. Methods: We used NSCLC cells (A549, NCI-H358) and normal human lung fibroblast (NHLF) cells to evaluate phenotypic changes in the presence of human IL-6, TGF-β1, and conditioned media (CM) from these cells. Possible pathways were evaluated with SB431542, a TGF-β receptor inhibitor, or an anti-human IL-6 receptor neutralizing antibody (IL-6R-Ab). Results: A549 and NCI-H358 cells incubated with IL-6 (50ng/mL) and TGF-β1 (2ng/mL) showed significantly increased epithelial–mesenchymal transition (EMT) signaling compared to those treated with TGF-β1 alone. Furthermore, NHLF cells were synergistically activated by IL-6 and TGF-β1. IL-6 increased the expression of TGF-β type I receptors on the surface of A549, NCI-H358 and NHLF cells and enhanced TGF-β signaling. TGF-β1 induced phenotypic changes were attenuated by IL-6R-Ab. NHLF cells were activated and A549 cells showed induction of EMT in response to CM from the other cell type. These activities were attenuated by SB431542 or IL-6R-Ab, suggesting that interplay between NSCLC cells and NHLF may lead to increased EMT signaling in NSCLC cells and activation of NHLF cells through TGF-β and IL-6 signaling. Subcutaneous co-injection of A549 and NHLF cells into mice resulted in a high rate of tumor formation compared with injection of A549 cells without NHLF cells. SB431542 or IL-6R-Ab also attenuated the tumor formation enhanced by co-injection of the two cell types. Conclusion: IL-6 enhanced epithelial cell EMT and stimulated tumor progression by enhancing TGF-β signaling. IL-6 and TGF-β may play a contributing role in maintenance of the paracrine loop between these two cytokines in the communication between fibroblasts and NSCLC cells for tumor progression. [Copyright &y& Elsevier]

We recently discovered a novel signaling pathway involving activin receptor-like kinase 7 (ALK7), one of the type I transforming growth factor-β receptors. ALK7 and activated Smads 2, 3, and 4 inhibit the master regulators of adipogenesis, CCAAT/enhancer-binding protein α (C/EBPα) and peroxisome proliferator-activated receptor γ (PP ARγ) specifically in differentiated adipocytes, but surprisingly increase both the adipocyte size and lipid content by suppressing lipolysis. Here, we show that, although both transcription factors are suppressed by ALK7 in either the obese or lean state, PPARγ, but not C/EBPα, is further suppressed under obesity through an ALK7-independent pathway. As a result, PPARγ and adipose lipolytic activities are severely downregulated in obesity. Reactivation of PPARγ by ALK7 inactivation leads to downregulation of inflammatory adipocytokines and upregulation of adiponectin. We propose that PPARγ promotes lipid turnover and remodeling by stimulating both triglyceride synthesis and breakdown in differentiated adipocytes. Finally, we discuss the physiological and evolutionary roles of the ALK7-signaling pathway and consider it as a potential target of therapy for obesity. [ABSTRACT FROM AUTHOR]

Based on the chain A structures of hemoglobin (PDB code: 1HDS, 1IBE, 1FAW, 3AT5), the three dimensional (3D) structure of natural velvet antler polypeptide (nVAP) was constructed by homology modeling and molecular dynamics (MD) method. The structural rationality was further checked by Profile-3D and Procheck, both of which confirmed that the 3D structure of nVAP was reasonable. The modeled structure indicates that the stable conformation of nVAP is composed of two α-helixes. The extracellular domains of transforming growth factor-β1 receptor I (TβRI-ED) and II (TβRII-ED) were docked with nVAP, respectively. The results show that both of TβR-EDs have high affinity with nVAP which locates near the active center of TβRII-ED integrating with transforming growth factor-β1 (TGF-β1). Otherwise, nVAP can also insert near the 'pre-helix extension' of TβRI-ED, which is the key domain to interact on TGF-β1 and TβRII-ED. With the perturbation of nVAP, TβRI-ED can not be recruited by TGF-β1:TβRII-ED complex rigorously. The intracellular domain of TβRI (TβRI-ID) is not phosphorylated and activated by TβRII. This study shows that nVAP prefers tethering TβRI-ED which is more crucial in TGF-β1:TβRII-ED:TβRI-ED complex. Thus nVAP can disturb the TGF-β1 binding pattern by interacting on TβRs (TβRI and TβRII), further intercepting TGF-β1 pathway downstream. [ABSTRACT FROM AUTHOR]

We present a 37-year-old woman who underwent extensive facial surgery for removal of multiple eruptive squamous cell carcinoma ( SCC)-like lesions resembling invasive SCC histologically. The patient's mother had undergone numerous surgical procedures and radiotherapy for facial SCC. A review of the histology and immunohistochemistry for DNA mismatch repair proteins excluded Muir- Torre syndrome. A diagnosis of Ferguson- Smith disease (or multiple self-healing squamous epitheliomata) was suspected. Blood was sent for DNA analysis. Twelve months later, mutations of the TGFBR1 gene were demonstrated in 18 families (67 individuals) with Ferguson- Smith disease; among whom our patient and her mother were family 11. [ABSTRACT FROM AUTHOR]

Aim:To study the influence of acute experimental diabetes on the regenerative potential of muscle stem (satellite) cells in mice.Methods:Male C57BL/6 young mice were injected with a single dose of streptozotocin (STZ, 180 mg/kg, ip) to induce diabetes. The diabetic mice were treated with insulin (0.75 U/kg, ip), follistatin (12 μg/kg, im) or Alk5 inhibitor (5 μmol/L per kg, sc) once a day. On the first day when high glucose levels were found, cardiotoxin (CTX) was focally injected into tibialis anterior and gastronemius muscles of the mice. The muscles were harvested 3 d and 5 d after CTX injection, and myofibers and satellite cells were isolated. Quantitative ex-vivo and in-vivo assays of myogenic potential were used to evaluate the muscle regenerative responses.Results:The satellite cells from the diabetic mice 3 d after CTX injection fail to activate, and the repair of muscle deteriorates, resembling that observed in old control mice. Furthermore, the satellite cells have excessive levels of myostatin, TGF-β receptor 1, pSmad3 and the cell cycle inhibitor p15, while the level of TGF-β1 remain unchanged. Treatment of the diabetic mice with insulin rescued muscle regenerative responses, and restored the expression levels of myostatin, TGF-β receptor 1, pSmad3, and p15 to those similar of healthy controls. Treatment of the diabetic mice with the myostatin antagonist follistatin, or with the Alk5 inhibitor of TGF-β receptor 1 (which did not diminish the blood glucose levels) rescued muscle regenerative responses and attenuated the myostatin/TGFβ receptor/pSmad3 signaling.Conclusion:The muscle regenerative responses are incapacitated and repair of the tissue fails within hours after the initiation of hyperglycemia in a mouse model of type 1 diabetes, but stem cell function is rescued by insulin, as well as follistatin or an Alk5 inhibitor that blocks TGF-β receptor signaling. [ABSTRACT FROM AUTHOR]

Inflammatory and anti-inflammatory cytokines play an important role in the generation of effector and memory CD8+ T cells. We used two different models, transgenic expression of truncated (dominant negative) form of TGF-βRII (dnTGFβRII) and Cre-mediated deletion of the floxed TGF-βRII to examine the role of TGF-β signaling in the formation, function, and homeostatic proliferation of memory CD8+ T cells. Blocking TGF-β signaling in effector CD8+ T cells using both of these models demonstrated a role for TGF-β in regulating the number of short-lived effector cells but did not alter memory CD8+ T cell formation and their function upon Listeria monocytogenes infection in mice. Interestingly, however, a massive lymphoproliferative disorder and cellular transformation were observed in Ag-experienced and homeostatically generated memory CD8+ T cells only in cells that express the dnTGFβRII and not in cells with a complete deletion of TGF-βRII. Furthermore, the development of transformed memory CD8+ T cells expressing dnTGFβRII was IL-7- and IL-15-independent, and MHC class I was not required for their proliferation. We show that transgenic expression of the dnTGFβRII, rather than the absence of TGF-βRII-mediated signaling, is responsible for dysregulated expansion of memory CD8+ T cells. This study uncovers a previously unrecognized dominant function of the dnTGFβRII in CD8+ T cell proliferation and cellular transformation, which is caused by a mechanism that is different from the absence of TGF-β signaling. These results should be considered during both basic and translational studies where there is a desire to block TGF-β signaling in CD8+ T cells. [ABSTRACT FROM AUTHOR]

NPC (nasopharyngeal carcinoma) is a common malignancy in southern China without defined aetiology. Recent studies have shown that TGFBR3 (transforming growth factor type III receptor, also known as betaglycan), exhibits anticancer activities. This study was to investigate the effects of TGFBR3 on NPC growth and the mechanisms for its actions. Effects of TGFBR3 overexpression on cell viability and apoptosis were measured by MTT [3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl-2H-tetrazolium bromide], AO/EB (acridine orange/ethidium bromide) staining and electron microscopy in human NPC CNE-2Z cells. The expression of apoptosis-related proteins, p-Bad, Bad, XIAP (X-linked inhibitor of apoptosis), AIF (apoptosis-inducing factor), Bax and Bcl-2, was determined by Western blot or immunofluorescence analysis. Caspase 3 activity was measured by caspase 3 activity kit and [Ca2+ ]i (intracellular Ca2+ concentration) was detected by confocal microscopy. Transfection of TGFBR3 containing plasmid DNA at concentrations of 0.5 and 1 μg/ml reduced viability and induced apoptosis in CNE-2Z in concentration- and time-dependent manners. Forced expression of TGFBR3 up-regulated pro-apoptotic Bad and Bax protein, and down-regulated anti-apoptotic p-Bad, Bcl-2 and XIAP protein. Furthermore, transient overexpression of TGFBR3 also enhanced caspase 3 activity, increased [Ca2+ ]i and facilitated AIF redistribution from the mitochondria to the nucleus in CNE-2Z cells, which is independent of the caspase 3 pathway. These events were associated with TGFBR3-regulated multiple targets involved in CNE-2Z proliferation. Therefore transient overexpression of TGFBR3 may be a novel strategy for NPC prevention and therapy. [ABSTRACT FROM AUTHOR]

Abstract: The Transforming Growth Factor beta (TGFβ) signaling pathway is necessary for a variety of normal cellular processes. However, the distinct mechanisms involved in TGFβ receptor turnover and the effect on signal transduction have yet to be fully elucidated. We have previously shown that TβRIII is able to interact with the TβRII/TβRI complex to increase clathrin-dependent endocytosis and receptor half-life. Others have shown that βarrestin2 binds TβRIII to mediate TβRII/TβRIII endocytosis. To further understand the mechanism regulating TGFβ receptor signaling, we evaluated the role of βarrestin2 in TGFβ receptor signal transduction, half-life and trafficking. We have found that TβRII binds βarrestin2 in the absence of TβRIII. Furthermore, using immunofluorescence microscopy we show that βarrestin2 traffics to the early endosome with TβRII. We investigated the effect of loss of βarrestin2 on TβRII dynamics and found that loss of βarrestin2 increases steady-state levels of TβRII at the cell surface. The interaction of TβRII with βarrestin2 is involved in modulating TGFβ signal transduction, as loss of βarrestin2 increases the phosphorylation of p38 and modestly affects pSmad levels. Using a luciferase assay to assess TGFβ-dependent transcription we show that loss of βarrestin2 decreases Smad-dependent TGFβ-stimulated transcription. Furthermore, loss of βarrestin2 increases p38 signal transduction, which correlated with increased cell death via apoptosis. Overall, our results suggest a role for βarrestin2 in the regulation of Smad-dependent and independent TGFβ pathways. [Copyright &y& Elsevier]

Background Mutations in the receptor genes of the transforming growth factor β pathway, TGFBR1 and TGFBR2, cause syndromes with thoracic aortic aneurysms, while genetic variants in TGFBR1 and TGFBR2 are associated with abdominal aortic aneurysms. The transforming growth factor-β pathway may be involved in aneurysm development in general. Aims To analyze whether genetics variants in TGFBR1 and TGFBR2 are also involved in the pathogenesis of intracranial aneurysms. Methods Using tag single nucleotide polymorphisms, we analyzed all common genetic variants in TGFBR1 (five single nucleotide polymorphisms) and TGFBR2 (26 single nucleotide polymorphisms) in a Dutch intracranial aneurysm case-control population approach using a two-stage genotyping approach. Results In stage 1, on analyzing 481 patients and 648 controls, two of the five single nucleotide polymorphisms in TGFBR1 were associated with intracranial aneurysm with P<0·10. In an independent cohort of 310 intracranial aneurysm patients and 376 controls, a predominance of the allele of the two single nucleotide polymorphisms found more frequently in patients in stage 1 was also observed in patients of stage 2 but the associations were not statistically significant. On combined analyses of both stages, there was a statistically significant association of both single nucleotide polymorphisms with intracranial aneurysm (single nucleotide polymorphism rs1626340, odds ratio 1·24, 95% confidence intervals 1·05-1·46, P=0·01; single nucleotide polymorphism rs10819634, odds ratio 1·23, 95% confidence intervals 1·03-1·46, P=0·02) but these associations did not hold after multiple testing correction (i.e., P<0·0016, 0·05/31). Also, no differences in the single nucleotide polymorphism frequency were observed for TGFBR2 between patients and controls. Conclusions We found no evidence for TGFBR1 and TGFBR2 as susceptibility genes for intracranial aneurysm in the Dutch population. [ABSTRACT FROM AUTHOR]

Objectives The aim of this study was to characterize the antileishmanial activity of heat-killed Mycobacterium indicus pranii (Mw) alone or in combination with a subtoxic dose of amphotericin B [AMB(st)]. Methods Mw- and Mw + AMB(st)-mediated antileishmanial activity was evaluated by microscopic counting of intracellular amastigotes in Giemsa-stained macrophages and real-time PCR analysis of inducible nitric oxide synthase (iNOS) expression and measurement of nitric oxide generation by Griess reagent. The relationship between Mw and Toll-like receptor 4 (TLR4) signalling was studied by fluorescence-activated cell sorting, western blot and confocal microscopy. The effect of Mw alone or in combination with AMB(st) on the expression and production of interleukin (IL)-12, tumour necrosis factor-α, IL-10 and transforming growth factor-β was analysed by real-time PCR and ELISA, respectively. Results Mw treatment alone or with AMB(st) caused a significant increase in TLR4 expression of L. donovani-infected macrophages along with the activation of TLR4 downstream signalling, facilitating active nuclear translocation of nuclear factor κB (NF-κB). These events culminated in the up-regulation of the proinflammatory response, which was abrogated by treatment with TLR4-specific small-interfering RNA. In addition, this study demonstrates that this chemoimmunotherapeutic strategy confers protection against leishmanial pathogenesis via TLR4-dependent counter-regulation of inducible nitric oxide synthase (iNOS) and arginase1 activity. Conclusions These results provide a mechanistic understanding of Mw- or Mw + AMB(st)-mediated protection against leishmanial parasites within host macrophages. [ABSTRACT FROM AUTHOR]

Summary: TGF-β1 is a multifunctional cytokine that mediates diverse biological processes. However, the mechanisms by which the intracellular signals of TGF-β1 are terminated are not well understood. Here, we demonstrate that DRAK2 serves as a TGF-β1-inducible antagonist of TGF-β signaling. TGF-β1 stimulation rapidly induces DRAK2 expression and enhances endogenous interaction of the type I TGF-β receptor with DRAK2, thereby blocking R-Smads recruitment. Depletion of DRAK2 expression markedly augmented the intensity and the extent of TGF-β1 responses. Furthermore, a high level of DRAK2 expression was observed in basal-like and HER2-enriched breast tumors and cell lines, and depletion of DRAK2 expression suppressed the tumorigenic ability of breast cancer cells. Thus, these studies define a function for DRAK2 as an intrinsic intracellular antagonist participating in the negative feedback loop to control TGF-β1 responses, and aberrant expression of DRAK2 increases tumorigenic potential, in part, through the inhibition of TGF-β1 tumor suppressor activity. [Copyright &y& Elsevier]

Abstract: Our laboratory has proved that 15-hydroxyeicosatetraenoic acid, a product of arachidonic acid catalyzed by 15-lipoxygenase (15-LO), plays a pivotal role in hypoxic pulmonary arterial hypertension. However, the mechanisms of how hypoxia regulates 15-LO expression are still unclear. As the formation of endogenous transforming growth factor-beta1 (TGF-β1), implicated in pulmonary arterial hypertension pathogenesis, was promoted by hypoxia, we suspect whether hypoxia-induced the expression of 15-LO is via the TGF-β1 pathway. We found that treatment of pulmonary artery smooth muscle cells with TGF-β1 significantly increased the expression of 15-LO and levels of 15-hydroxyeicosatetraenoic acid, product of 15-LO, which were inhibited by transforming growth factor-beta receptor I (TGFβRI) inhibitor, SD-208 and siRNA targeted to knockdown rat TGFβRI. Moreover, our results showed that TGF-β1 regulated the cell cycle progression and made more cells from the G0/G1 phase to the G2/M+S phase and enhanced the microtubule formation in cell nucleus. Additionally, we found that the 15-LO pathway was involved in TGFβ-1-mediated cell viability, DNA synthesis and the cell cycle progression. Our data provide novel evidence that hypoxia induced 15-LO expression is through TGF-β1, and 15-LO pathway plays a critical role in TGFβRI mediated the proliferation of pulmonary artery smooth muscle cells induced by hypoxia. Thus, new strategies aimed at combined blockade of TGFβRI as well as 15-LO may yield optimal therapeutic benefits. [Copyright &y& Elsevier]

Purpose: To examine the effectiveness of small-molecule inhibitor of transforming growth factor-β (TGF-β) type I receptor, an activin receptor-like kinase 5 (ALK5), on erectile dysfunction (ED) in a rat model of cavernous fibrosis, in which fibrosis was induced by intracavernous injection of adenovirus expressing TGF-β1 (Ad-TGF-β1). Materials and Methods: Four-month-old Sprague-Dawley rats were divided into four groups (n=10 per group): age-matched controls without treatment, age-matched controls receiving intracavernous injection of LacZ adenovirus, and cavernous fibrosis rats receiving an intracavernous injection of saline or ALK5 inhibitor (5 mg/kg). ALK5 inhibitor or saline was administered on day 5 after injection of Ad-TGF-β1. On day 30, erectile function was assessed by electrical stimulation of the cavernous nerve and the penis was then harvested for histologic studies (n=6 per group) and for the measurement of the hydroxyproline level (n=4 per group). Results: Ad-TGF-β1-induced cavernous fibrosis rats treated with saline showed a significant decrease in cavernous smooth muscle and endothelial content, and an increase in collagen deposition, which resulted in profound deterioration of all erectile function parameters, such as the ratios of maximal intracavernous pressure (ICP), total ICP, and slope to mean arterial pressure. ALK5 inhibitor significantly restored erectile function in a rat model of cavernous fibrosis by increasing cavernous smooth muscle and endothelial content, and by blocking cavernous fibrosis. Conclusions: The results suggest that inhibition of the TGF-β pathway is a promising therapeutic strategy for the treatment of ED related to cavernous fibrosis from various causes. [ABSTRACT FROM AUTHOR]

Abstract: A novel series of 4-thiazolylimidazoles was synthesized as transforming growth factor-β (TGF-β) type I receptor (also known as activin receptor-like kinase 5 or ALK5) inhibitors. These compounds were evaluated for their ALK5 inhibitory activity in an enzyme assay and their TGF-β-induced Smad2/3 phosphorylation inhibitory activity in a cell-based assay. N-{[5-(1,3-benzothiazol-6-yl)-4-(4-methyl-1,3-thiazol-2-yl)-1H-imidazol-2-yl]methyl}butanamide 20, a potent and selective ALK5 inhibitor, exhibited good enzyme inhibitory activity (IC50 =8.2nM) as well as inhibitory activity against TGF-β-induced Smad2/3 phosphorylation at a cellular level (IC50 =32nM). [Copyright &y& Elsevier]

Abstract: Pallister–Killian syndrome (PKS) is a potentially lethal disorder with facial dysmorphism, pigmentary skin anomalies, developmental delay and major visceral anomalies, such as diaphragmatic hernia, anorectal malformation, and congenital heart disease. PKS is causally associated with mosaic tetrasomy of chromosome 12p. A routine chromosome analysis in peripheral lymphocytes usually fails to detect the mosaic state. A prompt diagnosis rests on clinical awareness and a subsequent chromosome or molecular analysis in fibroblasts, buccal mucosal cells, or bone marrow cells. We report here on three infants with PKS. One infant had aortic dilatation, a previously unreported association in PKS. More importantly, all infants showed a recognizable, though mild, pattern of skeletal changes mainly affecting axial bones, including delayed ossification of the vertebral bodies and pubic bones, flared anterior ribs, and broad metaphyses of the long bones, particularly of the femora. These skeletal changes should be considered as a useful diagnostic sign in PKS. Awareness of the axial skeletal alterations can be helpful in prompting clinicians to search for mosaic tetrasomy 12p and perform chromosomal analysis in appropriate tissue types. [Copyright &y& Elsevier]

The type III TGF-β receptor (TβRIII or betagylcan) is a TGF-β superfamily coreceptor with emerging roles in regulating TGF-β superfamily signaling and cancer progression. Alterations in TGF-β superfamily signaling are common in colon cancer; however, the role of TβRIII has not been examined. Although TβRIII expression is frequently lost at the message and protein level in human cancers and suppresses cancer progression in these contexts, here we demonstrate that, in colon cancer, TβRIII messenger RNA expression is not significantly altered and TβRIII expression is more frequently increased at the protein level, suggesting a distinct role for TβRIII in colon cancer. Increasing TβRIII expression in colon cancer model systems enhanced ligand-mediated phosphorylation of p38 and the Smad proteins, while switching TGF-β and BMP-2 from inhibitors to stimulators of colon cancer cell proliferation, inhibiting ligand-induced p21 and p27 expression. In addition, increasing TβRIII expression increased ligand-stimulated anchorage-independent growth, a resistance to ligand- and chemotherapy-induced apoptosis, cell migration and modestly increased tumorigenicity in vivo. In a reciprocal manner, silencing endogenous TβRIII expression decreased colon cancer cell migration. These data support a model whereby TβRIII mediates TGF-β superfamily ligand-induced colon cancer progression and support a context-dependent role for TβRIII in regulating cancer progression. [ABSTRACT FROM AUTHOR]

Objective: Osteoarthritis (OA) is characterized by erosion of cartilage and formation of osteophytes. Since transforming growth factor beta (TGF-β) is known to be involved in chondrogenesis and osteogenesis, we studied by immunochemistry the expression of TGF-β isoform types 1, 2, and 3 and their receptor types I and II in slightly and strongly altered areas of human OA cartilage and in osteophytes. Methods: Specimens were collected from femoral heads at the time of hip arthroplasty, selecting osteophytic regions and areas of slight or severe degradation according to the Mankin score. Cryostat sections were prepared and submitted to immunohistochemistry using appropriate antibodies to TGF-β1-3 and TGF-β receptors I and II. Results: TGF-β1 expression was shown to be depressed in strongly degraded cartilage, compared to normal and slightly altered areas. TGF-β2 was barely detectable in all samples studied. In osteophytes, a marked overexpression of TGF-β1 and -β3 was observed. An important decrease in TGF-β receptor II was found in fibrillated cartilage areas. Conclusions: The three major isoforms of TGF-β are expressed in human OA cartilage, albeit the TGF-β2 level is very low. Their expression patterns and the ratio of receptors I and II varies according to the degree of OA severity. The decrease in TGF-β1 production and marked downregulation of receptor II in fibrillated cartilage may lead to reduced chondrocyte responsiveness to TGF-β and contribute to the irreversibility of the disease. Overexpression of TGF-β1 and -β3 in osteophytes suggests that the two isoforms are involved in the formation of these structures. [ABSTRACT FROM AUTHOR]

Numerous studies have demonstrated the involvement of the transforming growth factor (TGF) isoform β1 in the pathogenesis of renal fibroproliferative diseases. Although in vitro studies suggest that TGF-β2 is equally potent to TGF-β1 in terms of its antimitogenic and fibrogenic effects, much less is known about the regulation of TGF-β2 in renal diseases associated with glomerular cell hyperplasia and matrix expansion. Here we investigated the glomerular expression patterns of TGF-β2 and of the TGF-β receptors I, II, and III during the course of rat anti-Thy1.1 nephritis (days 2, 6, 12, and 56), a model characterized by transient mesangial hypercellularity and extracellular matrix accumulation. TGF-β2 exhibited dynamic changes in expression. Immunohistochemical double-staining of renal sections revealed that most TGF-β2-positive cells in control glomeruli were podocytes with few TGF-β2-positive mesangial cells. This staining pattern could also be observed in human kidney. On day 6 of anti-Thy1.1 nephritis both TGF-β2 positive podocytes and mesangial cells were more abundant. By western blot analysis of isolated glomeruli from nephritic rats, protein expression of TGF-β2 was upregulated tenfold over control glomeruli, peaking on day 6 of the disease. In cultured rat mesangial cells we found that the TGF-β2 and TGF-β1 isoforms were equally potent in terms of nuclear accumulation of phosphorylated Smad 2/3, inhibition of DNA synthesis, and induction of β1-integrin and type I collagen protein synthesis. Protein expression of the TGF-β receptor I was not detected by immunohistochemistry in control glomeruli but was markedly induced in the mesangium on day 6 of nephritis. Mesangial staining for TGF-β receptors II and III was detected in normal kidneys. Expression of TGF-β receptor II was strongly enhanced on days 6 and 12 of disease, while TGF-β receptor III was upregulated only on day 6. In summary, we report marked yet transient upregulation of TGF-β2 protein and of TGF-β receptors I, II, and III in glomerular cells during anti-Thy1.1 nephritis. These results are in keeping with the notion that TGF-β2 and its receptors participate in the pathogenesis and/or resolution of this transient form of glomerulonephritis. [ABSTRACT FROM AUTHOR]

Mutations in the genes encoding transforming growth factor b receptors 1 and 2 (TGFBR1 and TGFBR2) have recently been associated with hereditary connective tissue disorders with widespread vascular involvement, including arterial dissection. To determine whether mutations in these genes cause spontaneous cervical artery dissection (sCAD), all coding exons of TGFBR1 and TGFBR2 were sequenced in 56 consecutive patients with sCAD. Novel TGFBR2 disease causing mutations were found in two patients. The two mutations were the pK327R substitution affecting the kinase domain of TGFBR2 and the pC138R substitution falling in the extracellular domain of the protein, involved in TGFb binding and signalling. No TGFBR1 mutation was found. The findings indicate that TGFBR2 gene mutations are responsible for sCAD in 3.6% (95% CI 0.0 to 8.4) of cases, have implications in understanding the role of TGFb signalling in the pathogenesis of sCAD and emphasise the importance of considering molecular characterisation of the TGFBR2 gene in these patients, regardless of the presence of clinical features suggestive of hereditary connective tissue disorders. [ABSTRACT FROM AUTHOR]

Latent HIV infection is the main barrier to cure, and most HIV-infected cells reside in the gut, where distinct but unknown mechanisms may promote viral latency. Transforming growth factor β (TGF-β), which induces the expression of CD103 on tissue-resident memory T cells, has been implicated in HIV latency. Using CD103 as a surrogate marker to identify cells that have undergone TGF-β signaling, we compared the HIV RNA/DNA contents and cellular transcriptomes of CD103 + and CD103 - CD4 T cells from the blood and rectum of HIV-negative (HIV - ) and antiretroviral therapy (ART)-suppressed HIV-positive (HIV + ) individuals. Like gut CD4 + T cells, circulating CD103 + cells harbored more HIV DNA than did CD103 - cells but transcribed less HIV RNA per provirus. Circulating CD103 + cells also shared a gene expression profile that is closer to that of gut CD4 T cells than to that of circulating CD103 - cells, with significantly lower expression levels of ribosomal proteins and transcriptional and translational pathways associated with HIV expression but higher expression levels of a subset of genes implicated in suppressing HIV transcription. These findings suggest that blood CD103 + CD4 T cells can serve as a model to study the molecular mechanisms of HIV latency in the gut and reveal new cellular factors that may contribute to HIV latency. IMPORTANCE The ability of HIV to establish a reversibly silent, "latent" infection is widely regarded as the main barrier to curing HIV. Most HIV-infected cells reside in tissues such as the gut, but it is unclear what mechanisms maintain HIV latency in the blood or gut. We found that circulating CD103 + CD4 + T cells are enriched for HIV-infected cells in a latent-like state. Using RNA sequencing (RNA-seq), we found that CD103 + T cells share a cellular transcriptome that more closely resembles that of CD4 + T cells from the gut, suggesting that they are homing to or from the gut. We also identified the cellular genes whose expression distinguishes gut CD4 + or circulating CD103 + T cells from circulating CD103 - T cells, including some genes that have been implicated in HIV expression. These genes may contribute to latent HIV infection in the gut and may serve as new targets for therapies aimed at curing HIV., (Copyright © 2020 American Society for Microbiology.)

Summary Alveolar macrophages (AMs) derive from fetal liver monocytes, which colonize the lung during embryonic development and give rise to fully mature AMs perinatally. AM differentiation requires granulocyte macrophage colony-stimulating factor (GM-CSF), but whether additional factors are involved in AM regulation is not known. Here we report that AMs, in contrast to most other tissue macrophages, were also dependent on transforming growth factor-β receptor (TGF-βR) signaling. Conditional deletion of TGF-βR in mice at different time points halted the development and differentiation of AMs. In adult mice, TGF-β was also critical for AM homeostasis. The source of TGF-β was AMs themselves, indicative of an autocrine loop that promotes AM self-maintenance. Mechanistically, TGF-βR signaling resulted in upregulation of PPAR-γ, a signature transcription factor essential for the development of AMs. These findings reveal an additional layer of complexity regarding the guidance cues, which govern the genesis, maturation, and survival of AMs. [ABSTRACT FROM AUTHOR]

The article discusses the study "Integrin-mediated type II TGF-ß receptor tyrosine dephosphorylation controls SMAD-dependent profibrotic signaling," by X. Chen and colleagues in the August 1, 2014 issue of "The Journal of Clinical Investigation." Topics addressed include the role of transforming growth factor beta (TGF-ß) as a mediator of fibrosis, tyrosine kinases involved in TßRII phosphorylation, and the activation of the tyrosine phosphatase TCPTP.