Defining the mechanism of galectin-3-mediated TGF-ß1 activation and its role in lung fibrosis.

Integrin-mediated activation of the profibrotic mediator transforming growth factor-ß1 (TGF-ß1), plays a critical role in idiopathic pulmonary fibrosis (IPF) pathogenesis. Galectin-3 is believed to contribute to the pathological wound healing seen in IPF, although its mechanism of action is not precisely defined. We hypothesized that galectin-3 potentiates TGF-ß1 activation and/or signaling in the lung to promote fibrogenesis. We show that galectin-3 induces TGF-ß1 activation in human lung fibroblasts (HLFs) and specifically that extracellular galectin-3 promotes oleoyl-L-α-lysophosphatidic acid sodium salt-induced integrin-mediated TGF-ß1 activation. Surface plasmon resonance analysis confirmed that galectin-3 binds to αv integrins, αvß1, αvß5, and αvß6, and to the TGFßRII subunit in a glycosylation-dependent manner. This binding is heterogeneous and not a 1:1 binding stoichiometry. Binding interactions were blocked by small molecule inhibitors of galectin-3, which target the carbohydrate recognition domain. Galectin-3 binding to ß1 integrin was validated in vitro by coimmunoprecipitation in HLFs. Proximity ligation assays indicated that galectin-3 and ß1 integrin colocalize closely (≤40 nm) on the cell surface and that colocalization is increased by TGF-ß1 treatment and blocked by galectin-3 inhibitors. In the absence of TGF-ß1 stimulation, colocalization was detectable only in HLFs from IPF patients, suggesting the proteins are inherently more closely associated in the disease state. Galectin-3 inhibitor treatment of precision cut lung slices from IPF patients' reduced Col1a1, TIMP1, and hyaluronan secretion to a similar degree as TGF-ß type I receptor inhibitor. These data suggest that galectin-3 promotes TGF-ß1 signaling and may induce fibrogenesis by interacting directly with components of the TGF-ß1 signaling cascade.

Polymorphic markers of several immune regulatory genes modulate the susceptibility for eczema and related phenotypes in children.

Background: Eczema is associated with multiple genes regulating epidermal barrier functions and immunological pathways. However, their epistatic interactions are not well studied. This cross-sectional study investigated the relationship between childhood eczema phenotypes and single-nucleotide polymorphisms (SNPs) of immune regulatory genes. Methods: One thousand three hundred and twenty-nine Chinese eczematous children and 1,179 non-allergic controls were recruited. Nine SNPs of immune regulatory genes signal transducer and activator of transcription 3 (STAT3), interleukin-10 (IL10), transforming growth factor-beta 1 (TGFB1), and IL-6 receptor (IL6R) were genotyped by TaqMan genotyping assays. Logistic regression was used to analyze the associations between SNPs and eczema phenotypes. Generalized multifactor dimensionality reduction (GMDR) was used to examine epistatic interactions among these SNPs as well as those reported by our group [filaggrin (FLG) and 11q13] for eczema phenotypes. Results: TGFB1_rs1800469 was found to be associated with eczema [odds ratio (OR), 0.82; 95% confidence interval (CI): 0.73-0.92; P=0.001], atopic eczema (OR, 0.83; 95% CI: 0.72-0.95; P=0.009) and allergic rhinitis (OR, 0.84; 95% CI: 0.74-0.95; P=0.005). We also found a trend between IL10_rs1800872 and increased total immunoglobulin E (IgE) levels (P=0.009). Epistatic interaction among IL10_rs3021094, TGFB1_rs1800469, IL6R_rs2228145, and STAT3_rs4796793 were found for total IgE [testing accuracy (TA), 0.551; cross-validation consistency (CVC), 10; P=0.014]. Mean log-transformed total IgE (logIgE) levels in high-risk cases, low-risk cases, high-risk controls, and low-risk controls were 2.75, 2.60, 1.90, and 1.81 respectively (P=0.019 for trend). Conclusions: Functional TGFB1 polymorphism is associated with both eczema and allergic rhinitis, suggesting the role of TGF-ß1 in allergy susceptibility. IL10 may be associated with increased total IgE levels. Interaction among immune regulatory genes modulates total IgE levels.

Nano-chemical priming strategy to enhance TGF-ß resistance and anti-tumor activity of natural killer cells.

Immunotherapy based on adoptive transfer of natural killer (NK) cells is a promising strategy for circumventing the limitations of cancer treatments. However, components of the immunosuppressive tumor microenvironment (TME), such as transforming growth factor-beta (TGF-ß), compromise the therapeutic efficacy of NK cells significantly. To address these limitations, we developed a novel method of engineering NK cells for adaptive transfer. The method is based on nanogels that serve two functions: (1) they overcome the TGF-ß-mediated stress environment of the TME, and (2) they enhance the direct anti-tumor activity of NK cells. Previously, we demonstrated that cationic compounds such as 25 K branched polyethylenimine (25 K bPEI) prime NK cells, putting them in a 'ready-to-fight' state. Based on these findings, we designed nanogels that have two primary characteristics: (1) they encapsulate galunisertib (Gal), which is used clinically to inhibit TGF-ß receptor activity, thereby blocking TGF-ß signaling; and (2) they provide cells with a surface coating of 25 K bPEI. When grown in culture medium containing TGF-ß, nanogel-treated NK cells demonstrated greater migration ability, degranulation activity, and cytotoxicity towards cancer cells than untreated NK cells. Additionally, the in vivo efficacy of nanogel-treated NK cells against PC-3 xenografts was significantly greater than that of Chem_NK cells primed by 25 K bPEI alone. These findings suggest that Gal-loaded 25 K bPEI-coated nanogels exert anti-tumor effects via chemical priming, as well suppressing the effects of TGF-ß on NK cells. We also expect 25 K bPEI-based nanogels to have great potential to overcome the suppressive effects of the TME through their NK cell-priming activity and delivery of the desired chemicals.

KLF6 activates Sp1-mediated prolidase transcription during TGF-ß1 signaling.

Prolidase (PEPD) is the only hydrolase that cleaves the dipeptides containing C-terminal proline or hydroxyproline-the rate-limiting step in collagen biosynthesis. However, the molecular regulation of prolidase expression remains largely unknown. In this study, we have identified overlapping binding sites for the transcription factors Krüppel-like factor 6 (KLF6) and Specificity protein 1 (Sp1) in the PEPD promoter and demonstrate that KLF6/Sp1 transcriptionally regulate prolidase expression. By cloning the PEPD promoter into a luciferase reporter and through site-directed deletion, we pinpointed the minimal sequences required for KLF6 and Sp1-mediated PEPD promoter-driven transcription. Interestingly, Sp1 inhibition abrogated KLF6-mediated PEPD promoter activity, suggesting that Sp1 is required for the basal expression of prolidase. We further studied the regulation of PEPD by KLF6 and Sp1 during transforming growth factor ß1 (TGF-ß1) signaling, since both KLF6 and Sp1 are key players in TGF-ß1 mediated collagen biosynthesis. Mouse and human fibroblasts exposed to TGF-ß1 resulted in the induction of PEPD transcription and prolidase expression. Inhibition of TGF-ß1 signaling abrogated PEPD promoter-driven transcriptional activity of KLF6 and Sp1. Knock-down of KLF6 as well as Sp1 inhibition also reduced prolidase expression. Chromatin immunoprecipitation assay supported direct binding of KLF6 and Sp1 to the PEPD promoter and this binding was enriched by TGF-ß1 treatment. Finally, immunofluorescence studies showed that KLF6 co-operates with Sp1 in the nucleus to activate prolidase expression and enhance collagen biosynthesis. Collectively, our results identify functional elements of the PEPD promoter for KLF6 and Sp1-mediated transcriptional activation and describe the molecular mechanism of prolidase expression.

Proactive and reactive roles of TGF-ß in cancer.

Cancer cells adapt to varying stress conditions to survive through plasticity. Stem cells exhibit a high degree of plasticity, allowing them to generate more stem cells or differentiate them into specialized cell types to contribute to tissue development, growth, and repair. Cancer cells can also exhibit plasticity and acquire properties that enhance their survival. TGF-ß is an unrivaled growth factor exploited by cancer cells to gain plasticity. TGF-ß-mediated signaling enables carcinoma cells to alter their epithelial and mesenchymal properties through epithelial-mesenchymal plasticity (EMP). However, TGF-ß is a multifunctional cytokine; thus, the signaling by TGF-ß can be detrimental or beneficial to cancer cells depending on the cellular context. Those cells that overcome the anti-tumor effect of TGF-ß can induce epithelial-mesenchymal transition (EMT) to gain EMP benefits. EMP allows cancer cells to alter their cell properties and the tumor immune microenvironment (TIME), facilitating their survival. Due to the significant roles of TGF-ß and EMP in carcinoma progression, it is essential to understand how TGF-ß enables EMP and how cancer cells exploit this plasticity. This understanding will guide the development of effective TGF-ß-targeting therapies that eliminate cancer cell plasticity.

Evidence for the expression of vasorin in the human female reproductive tissues.

Objective: To investigate the expression and localization of Vasorin (Vasn) in human female reproductive system. Methods: The presence of Vasorin was evaluated by RT-PCR and immunoblotting analyses in patient-derived endometrial, myometrial and granulosa cells (GCs) primary cultures. Immunostaining analyses were performed to detect Vasn localization in primary cultures and in ovarian and uterine tissues. Results: Vasn mRNA was detected in patient-derived endometrial, myometrial and GCs primary cultures without significant differences at the transcript level. Otherwise, immunoblotting analysis showed that Vasn protein levels were significantly higher in GCs than proliferative endometrial stromal cells (ESCs) and myometrial cells. Immunohistochemistry performed in ovarian tissues revealed that Vasn was expressed in the GCs of ovarian follicles at different stages of development with a higher immunostaining signal in mature ovarian follicles such as the antral follicle or on the surface of cumulus oophorus cells than in early-stage follicles. The immunostaining of uterine tissues showed that Vasn was expressed in the proliferative stroma endometrium while it was significantly less expressed in the secretory endometrium. Conversely, no protein immunoreactivity was revealed in health myometrial tissue. Conclusions: Our results revealed the presence of Vasn in the ovary and the endometrium. The pattern of Vasn expression and distribution suggests that this protein may have a role in the regulation of processes such as folliculogenesis, oocyte maturation, and endometrial proliferation.

Mutual regulation between glycosylation and transforming growth factor-ß isoforms signaling pathway.

Transforming growth factor-beta (TGF-ß) superfamily members orchestrate a wide breadth of biological processes. Through Sma and Mad (Smad)-related dependent or noncanonical pathways, TGF-ß members involve in the occurrence and development of many diseases such as cancers, fibrosis, autoimmune diseases, cardiovascular diseases and brain diseases. Glycosylation is one kind of the most common posttranslational modifications on proteins or lipids. Abnormal protein glycosylation can lead to protein malfunction and biological process disorder, thereby causing serious diseases. Previously, researchers commonly make comprehensive systematic overviews on the roles of TGF-ß signaling in a specific disease or biological process. In recent years, more and more evidences associate glycosylation modification with TGF-ß signaling pathway, and we can no longer disengage and ignore the roles of glycosylation from TGF-ß signaling to make investigation. In this review, we provide an overview of current findings involved in glycosylation within TGF-ßs and theirs receptors, and the interaction effects between glycosylation and TGF-ß subfamily signaling, concluding that there is an intricate mutual regulation between glycosylation and TGF-ß signaling, hoping to present the glycosylation regulatory patterns that concealed in TGF-ßs signaling pathways.

FGF-2 Differentially Regulates Lens Epithelial Cell Behaviour during TGF-ß-Induced EMT.

Fibroblast growth factor (FGF) and transforming growth factor-beta (TGF-ß) can regulate and/or dysregulate lens epithelial cell (LEC) behaviour, including proliferation, fibre differentiation, and epithelial-mesenchymal transition (EMT). Earlier studies have investigated the crosstalk between FGF and TGF-ß in dictating lens cell fate, that appears to be dose dependent. Here, we tested the hypothesis that a fibre-differentiating dose of FGF differentially regulates the behaviour of lens epithelial cells undergoing TGF-ß-induced EMT. Postnatal 21-day-old rat lens epithelial explants were treated with a fibre-differentiating dose of FGF-2 (200 ng/mL) and/or TGF-ß2 (50 pg/mL) over a 7-day culture period. We compared central LECs (CLECs) and peripheral LECs (PLECs) using immunolabelling for changes in markers for EMT (α-SMA), lens fibre differentiation (ß-crystallin), epithelial cell adhesion (ß-catenin), and the cytoskeleton (alpha-tropomyosin), as well as Smad2/3- and MAPK/ERK1/2-signalling. Lens epithelial explants cotreated with FGF-2 and TGF-ß2 exhibited a differential response, with CLECs undergoing EMT while PLECs favoured more of a lens fibre differentiation response, compared to the TGF-ß-only-treated explants where all cells in the explants underwent EMT. The CLECs cotreated with FGF and TGF-ß immunolabelled for α-SMA, with minimal ß-crystallin, whereas the PLECs demonstrated strong ß-crystallin reactivity and little α-SMA. Interestingly, compared to the TGF-ß-only-treated explants, α-SMA was significantly decreased in the CLECs cotreated with FGF/TGF-ß. Smad-dependent and independent signalling was increased in the FGF-2/TGF-ß2 co-treated CLECs, that had a heightened number of cells with nuclear localisation of Smad2/3 compared to the PLECs, that in contrast had more pronounced ERK1/2-signalling over Smad2/3 activation. The current study has confirmed that FGF-2 is influential in differentially regulating the behaviour of LECs during TGF-ß-induced EMT, leading to a heterogenous cell population, typical of that observed in the development of post-surgical, posterior capsular opacification (PCO). This highlights the cooperative relationship between FGF and TGF-ß leading to lens pathology, providing a different perspective when considering preventative measures for controlling PCO.

AjTGFß alleviates V. splendidus-induced inflammation through SMADs pathway in Apostichopus japonicus.

The inhibition of inflammatory response is an essential process to control the development of inflammation and is an important step to protect the organism from excessive inflammatory damage. As a pleiotropic cytokine, transforming growth factor beta (TGF-ß) plays a regulatory role in inhibiting inflammation in vertebrates. To investigate the role of TGF-ß in the regulation of inflammation in invertebrates, we cloned and characterized the TGF-ß gene from Apostichopus japonicus via rapid amplification of cDNA ends, and the sample was designated as AjTGF-ß. For Vibrio splendidus-challenged sea cucumbers, the expression of AjTGF-ß mRNAs in coelomocytes decreased at 96 h (0.27-fold), which was contrary to the trend of inflammation. AjTGF-ß was expressed in all tissues with the highest expression in the body wall. When AjTGF-ß was knocked down by using small interfering RNA (siRNA-KD) to 0.45-fold, AjSMAD 2/3 and AjSMAD6 were downregulated to 0.32- and 0.05-fold compared with the control group, respectively. Furthermore, when the damaged sea cucumber was challenged by V. splendidus co-incubated with rAjTGF-ß, the damage area had no extensive inflammation, and damaged repair appeared at 72 h compared with the Vs + BSA group, in which the expression of AjSMAD 2/3 was upregulated by 1.35-fold. Under this condition, AjSMAD 2/3 silencing alleviated rAjTGF-ß-induced damage recovery. Moreover, rAjTGF-ß slightly induced the collagen I expression from 6.13 ng/mL to 7.84 ng/mL, and collagen III was upregulated from 6.23 ng/mL to 6.89 ng/mL compared with the Vs + BSA group. This finding indicates that AjTGF-ß negatively regulated the inflammatory progress and accelerated the repair of damage by AjSMADs to regulate the collagens expression.

A Review on Major Pathways Leading to Peritoneal Fibrosis in Patients Receiving Continuous Peritoneal Dialysis.

Peritoneal fibrosis (PF) is the most important complication of peritoneal dialysis (PD) that may arise among patients receiving continuous ambulatory peritoneal dialysis (CAPD). PF is a complex process, and many factors contribute to the formation of fibrosis. PD solutions with high glucose content, chronic inflammation, inflammatory cytokines, angiogenesis, and mesothelial to mesenchymal transition (MMT) are factors contributing to the fibrosis of the peritoneum. These factors, as well as stress-induced fibrosis, are going to be discussed further in this article. Although most experimental models are promising in preventing or delaying PD-related fibrosis, most of these recommended treatment options require further research. The lack of sufficient data from real PD patients and many inconclusive data make clinicians depend on conservative treatment. New therapeutics are indeed required for the management of patients undergoing PD to prevent the dreaded complication that may arise from continuous PD. Newer PD solutions are needed to improve survival and minimize the complication associated with PD. Recently, newer PD solutions have been shown to improve patient survival and peritoneal viability and reduce this complication that may arise as a result of continuous PD.

CD82 attenuates TGF-ß1-mediated epithelial-mesenchymal transition by blocking smad-dependent signaling in ARPE-19 cells.

In retinal pigment epithelial (RPE) cells, transforming growth factor-beta (TGF-ß) plays a critical role in epithelial-mesenchymal transition (EMT), which contributes to various fibrotic retinal disorders. In the present study, we investigated the effect of recombinant human cluster of differentiation 82 (rhCD82), a tumor metastasis suppressor, on TGF-ß-induced EMT in the human RPE cell line APRE-19. The results show that TGF-ß1 significantly enhanced cell migration, invasion and the expression of EMT-mediate factors in ARPE-19 cells. However, rhCD82 markedly inhibited cell mobility and the expression of epithelial marker, zonula occludens-1, as well as increased the expression of mesenchymal markers, such as vimentin and α-smooth muscle actin in TGF-ß1-treated APRE-19 cells. In addition, TGF-ß1 upregulated the phosphorylation of Smad, extracellular signal regulated kinase (ERK) and glycogen synthase kinase-3ß (GSK-3ß), but only phosphorylation of Smad was suppressed by rhCD82. Noteworthy, rhCD82 greatly suppressed the expression of TGF-ß receptor I (TGFRI), TGFRII and integrins in TGF-ß1-treated APRE-19 cells. In particular, the result of molecular docking analysis and structural modeling show that rhCD82 partially interacts with the TGF-ß1 binding sites of TGFRI, TGFRII, integrin ß1 and integrin αv. Taken together, this finding suggested that rhCD82 suppressed TGF-ß1-induced EMT of RPE by blocking of Smad-dependent pathway, which is caused by rhCD82 interaction with TGFRs and integrins, suggesting new insight into CD82 as a potential therapeutic strategy in fibrotic retinal disorders.

Insulin facilitates corneal wound healing in the diabetic environment through the RTK-PI3K/Akt/mTOR axis in vitro.

Diabetic patients can develop degenerative corneal changes, termed diabetic keratopathy, during the course of their disease. Topical insulin has been shown to reduce corneal wound area and restore sensitivity in diabetic rats, and both the insulin receptor (IR) and insulin-like growth factor 1 receptor (IGF-1R) stimulate cell signaling of the PI3K-Akt pathway. The purpose of this study was to assess a mechanism by which improved wound healing occurs by characterizing expression within the PI3K-Akt pathway in corneal epithelial and stromal cells. In vitro scratch tests were used to evaluate wound healing outcomes under variable glucose conditions in the presence or absence of insulin. Protein expression of intracellular kinases in the PI3K pathway, stromal cell markers, and GLUT-1 was evaluated by immunoblotting.TGF-ß1 expression was evaluated by ELISA. Insulin promoted in vitro wound healing in all cell types. In human corneal epithelial cells, insulin did not induce PI3K-Akt signaling; however, in all other cell types evaluated, insulin increased expression of PI3K-Akt signaling proteins compared to vehicle control. Fibroblasts variably expressed α-SMA under all treatment conditions, with significant increases in α-SMA and TGF-ß1 occurring in a dose-dependent manner with glucose concentration. These results indicate that insulin can promote corneal cellular migration and proliferation by inducing Akt signaling. Exogenous insulin therapy may serve as a novel target of therapeutic intervention for diabetic keratopathy.

Role of TGF-ß signaling in the mechanisms of tamoxifen resistance.

The transforming growth factor beta (TGF-ß) signaling pathway plays complex role in the regulation of cell proliferation, apoptosis and differentiation in breast cancer. TGF-ß activation can lead to multiple cellular responses mediating the drug resistance evolution, including the resistance to antiestrogens. Tamoxifen is the most commonly prescribed antiestrogen that functionally involved in regulation of TGF-ß activity. In this review, we focus on the role of TGF-ß signaling in the mechanisms of tamoxifen resistance, including its interaction with estrogen receptors alfa (ERα) pathway and breast cancer stem cells (BCSCs). We summarize the current reported data regarding TGF-ß signaling components as markers of tamoxifen resistance and review current approaches to overcoming tamoxifen resistance based on studies of TGF-ß signaling.

ß-cell Smad2 null mice have improved ß-cell function and are protected from diet-induced hyperglycemia.

Understanding signaling pathways that regulate pancreatic ß-cell function to produce, store, and release insulin, as well as pathways that control ß-cell proliferation, is vital to find new treatments for diabetes mellitus. Transforming growth factor-beta (TGF-ß) signaling is involved in a broad range of ß-cell functions. The canonical TGF-ß signaling pathway functions through intracellular smads, including smad2 and smad3, to regulate cell development, proliferation, differentiation, and function in many organs. Here, we demonstrate the role of TGF-ß/smad2 signaling in regulating mature ß-cell proliferation and function using ß-cell-specific smad2 null mutant mice. ß-cell-specific smad2-deficient mice exhibited improved glucose clearance as demonstrated by glucose tolerance testing, enhanced in vivo and ex vivo glucose-stimulated insulin secretion, and increased ß-cell mass and proliferation. Furthermore, when these mice were fed a high-fat diet to induce hyperglycemia, they again showed improved glucose tolerance, insulin secretion, and insulin sensitivity. In addition, ex vivo analysis of smad2-deficient islets showed that they displayed increased glucose-stimulated insulin secretion and upregulation of genes involved in insulin synthesis and insulin secretion. Thus, we conclude that smad2 could represent an attractive therapeutic target for type 2 diabetes mellitus.

Suberoylanilide hydroxamic acid (SAHA) inhibits transforming growth factor-beta 2-induced increases in aqueous humor outflow resistance.

Transforming growth factor-beta 2 (TGF-ß2) is highly concentrated in the aqueous humor of primary open-angle glaucoma patients. TGF-ß2 causes fibrosis of outflow tissues, such as the trabecular meshwork (TM), and increases intraocular pressure by increasing resistance to aqueous humor outflow. Recently, histone deacetylase (HDAC) activity was investigated in fibrosis in various tissues, revealing that HDAC inhibitors suppress tissue fibrosis. However, the effect of HDAC inhibitors on fibrosis in the eye was not determined. Here, we investigated the effect of suberoylanilide hydroxamic acid (SAHA), an HDAC inhibitor, on TGF-ß2-induced increased resistance to aqueous humor outflow. We found that SAHA suppressed TGF-ß2-induced outflow resistance in perfused porcine eyes. Moreover, SAHA cotreatment suppressed TGF-ß2-induced ocular hypertension in rabbits. The permeability of monkey TM (MTM) and Schlemm's canal (MSC) cell monolayers was decreased by TGF-ß2 treatment. SAHA inhibited the effects of TGF-ß2 on the permeability of these cells. TGF-ß2 also increased the expression of extracellular matrix proteins (fibronectin and collagen type I or IV) in MTM, MSC, and human TM (HTM) cells, while SAHA inhibited TGF-ß2-induced extracellular matrix protein expression in these cells. SAHA also inhibited TGF-ß2-induced phosphorylation of Akt and ERK, but did not inhibit Smad2/3 phosphorylation, the canonical pathway of TGF-ß signaling. Moreover, SAHA induced the expression of phosphatase and tensin homolog, a PI3K/Akt signaling factor, as well as bone morphogenetic protein 7, an endogenous antagonist of TGF-ß. These results imply that SAHA prevents TGF-ß2-induced increases in outflow resistance and regulates the non-Smad pathway of TGF-ß signaling in TM and MSC cells.

Prostate Cancer Immunotherapy-Finally in From the Cold?

PURPOSE OF REVIEW: Despite significant progress, patients with metastatic prostate cancer continue to have poor prognosis. Immunotherapy has revolutionized cancer care for many tumor types but has a limited role in the treatment of prostate cancer. This review discusses the promise of immunotherapy in prostate cancer treatment with an emphasis on emerging therapeutic targets. RECENT FINDINGS: Most prostate tumors have low tumor mutational burden and lack immunogenicity, representing significant hurdles to induction of anti-tumor immunity. However, recent research centered on deciphering key mechanisms of immune resistance in the prostate tumor microenvironment has led to the discovery of a range of new treatment targets. These discoveries are currently being translated into innovative immunotherapy clinical trials for patients with prostate cancer. Recent progress includes early evidence of activity for these novel approaches and the identification of potential predictive biomarkers of response. Novel treatment strategies using new antigen-directed therapies, drugs targeting the immunosuppressive tumor microenvironment, and combination immunotherapy therapies show great potential and are currently in clinical development. In addition, a deeper understanding of predictors of response and resistance to immunotherapy in prostate cancer is allowing for a more personalized approach to therapy.

The Fibronectin Expression Determines the Distinct Progressions of Malignant Gliomas via Transforming Growth Factor-Beta Pathway.

Due to the increasing incidence of malignant gliomas, particularly glioblastoma multiforme (GBM), a simple and reliable GBM diagnosis is needed to screen early the death-threaten patients. This study aimed to identify a protein that can be used to discriminate GBM from low-grade astrocytoma and elucidate further that it has a functional role during malignant glioma progressions. To identify proteins that display low or no expression in low-grade astrocytoma but elevated levels in GBM, glycoprotein fibronectin (FN) was particularly examined according to the mining of the Human Protein Atlas. Web-based open megadata minings revealed that FN was mainly mutated in the cBio Cancer Genomic Portal but dominantly overexpressed in the ONCOMINE (a cancer microarray database and integrated data-mining platform) in distinct tumor types. Furthermore, numerous different cancer patients with high FN indeed exhibited a poor prognosis in the PrognoScan mining, indicating that FN involves in tumor malignancy. To investigate further the significance of FN expression in glioma progression, tumor specimens from five malignant gliomas with recurrences that received at least two surgeries were enrolled and examined. The immunohistochemical staining showed that FN expression indeed determined the distinct progressions of malignant gliomas. Furthermore, the expression of vimentin (VIM), a mesenchymal protein that is strongly expressed in malignant cancers, was similar to the FN pattern. Moreover, the level of epithelial-mesenchymal transition (EMT) inducer transforming growth factor-beta (TGF-ß) was almost recapitulated with the FN expression. Together, this study identifies a protein FN that can be used to diagnose GBM from low-grade astrocytoma; moreover, its expression functionally determines the malignant glioma progressions via TGF-ß-induced EMT pathway.

Overcoming the Immunosuppressive Tumor Microenvironment in Multiple Myeloma.

SeverFigurel cellular elements of the bone marrow (BM) microenvironment in multiple myeloma (MM) patients contribute to the immune evasion, proliferation, and drug resistance of MM cells, including myeloid-derived suppressor cells (MDSCs), tumor-associated M2-like, "alternatively activated" macrophages, CD38+ regulatory B-cells (Bregs), and regulatory T-cells (Tregs). These immunosuppressive elements in bidirectional and multi-directional crosstalk with each other inhibit both memory and cytotoxic effector T-cell populations as well as natural killer (NK) cells. Immunomodulatory imide drugs (IMiDs), protease inhibitors (PI), monoclonal antibodies (MoAb), adoptive T-cell/NK cell therapy, and inhibitors of anti-apoptotic signaling pathways have emerged as promising therapeutic platforms that can be employed in various combinations as part of a rationally designed immunomodulatory strategy against an immunosuppressive tumor microenvironment (TME) in MM. These platforms provide the foundation for a new therapeutic paradigm for achieving improved survival of high-risk newly diagnosed as well as relapsed/refractory MM patients. Here we review the scientific rationale and clinical proof of concept for each of these platforms.

Potential Second-Hits in Hereditary Hemorrhagic Telangiectasia.

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant genetic disorder that presents with telangiectases in skin and mucosae, and arteriovenous malformations (AVMs) in internal organs such as lungs, liver, and brain. Mutations in ENG (endoglin), ACVRL1 (ALK1), and MADH4 (Smad4) genes account for over 95% of HHT. Localized telangiectases and AVMs are present in different organs, with frequencies which differ among affected individuals. By itself, HHT gene heterozygosity does not account for the focal nature and varying presentation of the vascular lesions leading to the hypothesis of a "second-hit" that triggers the lesions. Accumulating research has identified a variety of triggers that may synergize with HHT gene heterozygosity to generate the vascular lesions. Among the postulated second-hits are: mechanical trauma, light, inflammation, vascular injury, angiogenic stimuli, shear stress, modifier genes, and somatic mutations in the wildtype HHT gene allele. The aim of this review is to summarize these triggers, as well as the functional mechanisms involved.

Differential Expression of Circulating Plasma miRNA-370 and miRNA-10a from Patients with Hereditary Hemorrhagic Telangiectasia.

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant, vascular disorder that presents with telangiectases and arteriovenous malformations. HHT is a genetically heterogeneous disorder, involving mutations in endoglin (ENG; HHT1) and activin receptor-like kinase 1 (ACVRL1/ALK1; HHT2) genes that account for over 85% of all HHT patients. The current diagnosis of HHT patients remains at the clinical level, but many suspected patients do not have a clear HHT diagnosis or do not show pathogenic mutations in HHT genes. This situation has prompted the search for biomarkers to help in the early diagnosis of the disease. We have analyzed the plasma levels in HHT patients of selected micro-RNAs (miRNAs), small single-stranded RNAs that regulate gene expression at the transcriptional level by interacting with specific RNA targets. A total of 16 HHT1 and 17 HHT2 plasma samples from clinically confirmed patients and 16 controls were analyzed in this study. Total RNA was purified from plasma, and three selected miRNAs (miRNA-10a, miRNA-214, and miRNA-370), related to the pathobiology of cardiovascular diseases and potentially targeting ENG or ALK1, were measured by quantitative polymerase chain reaction. Compared with controls, levels of miRNA-370, whose putative target is ENG, were significantly downregulated in HHT1, but not in HHT2, whereas the levels of miRNA-10a, whose putative target is ALK1, were significantly upregulated in HHT2, but not in HHT1. In addition, the levels of miRNA-214, potentially targeting ENG and ALK1, did not change in either HHT1 or HHT2 patients versus control samples. While further studies are warranted, these results suggest that dysregulated plasma levels of miRNA-370 or miRNA-10a could help to identify undiagnosed HHT1 or HHT2 patients, respectively.