Cytokines and chemokines as regulators of angiogenesis in health and disease

Decellularized tissues as platforms for digestive system cancer models

The extracellular matrix (ECM) is a multifunctional network of macromolecules that regulate various cellular functions and physically support the tissues. Besides physiological conditions, the ECM also changes during pathological conditions such as cancer. As tumor cells proliferate, notable changes occur in the quantity and makeup of the surrounding ECM. Therefore, the role of this noncellular component of tissues in studies of tumor microenvironments should be considered. So far, many attempts have been made to create 2-dimensional (2D) or 3-dimensional (3D) models that can replicate the intricate connections within the tumor microenvironment. Decellularized tissues are proper scaffolds that imitate the complex nature of native ECM. This review aims to summarize 3D models of digestive system cancers based on decellularized ECMs. These ECM-based scaffolds will enable us to study the interactive communication between cells and their surrounding environment which brings new potential for a better understanding of the pathophysiology of cancer.

Costic acid, a sesquiterpene from Nectandra barbellata (Lauraceae), attenuates sponge implant-induced inflammation, angiogenesis and collagen deposition in vivo

Sesquiterpenes are a class of metabolites derived from plant species with immunomodulatory activity. In this study, we evaluated the effects of treatment with costic acid on inflammation, angiogenesis, and fibrosis induced by subcutaneous sponge implants in mice. One sponge disc per animal was aseptically implanted in the dorsal region of the mice and treated daily with costic acid (at concentrations of 0.1, 1, and 10 μg diluted in 10 μL of 0.5% DMSO) or 0.5% DMSO (control group). After 9 days of treatment, the animals were euthanized, and the implants collected for further analysis. Treatment with costic acid resulted in the reduction of the inflammatory parameters evaluated compared to the control group, with a decrease in the levels of inflammatory cytokines and chemokines (TNF, CXCL-1, and CCL2) and in the activity of MPO and NAG enzymes. Costic acid administration altered the process of mast cell degranulation. We also observed a reduction in angiogenic parameters, such as a decrease in the number of blood vessels, the hemoglobin content, and the levels of VEGF and FGF cytokines. Finally, when assessing implant-induced fibrogenesis, we observed a reduction in the levels of the pro-fibrogenic cytokine TGF-β1, and lower collagen deposition. The results of this study demonstrate, for the first time, the anti-inflammatory, anti-angiogenic, and anti-fibrotic effects of costic acid in an in vivo model of chronic inflammation and reinforce the therapeutic potential of costic acid.

Atovaquone inhibits colorectal cancer metastasis by regulating PDGFRβ/NF-κB signaling pathway

BACKGROUND

Colorectal cancer is a common malignant tumour. Invasive growth and distant metastasis are the main characteristics of its malignant biological behaviour, and they are also the primary factors leading to death in colon cancer patients. Atovaquone is an antimalarial drug, and its anticancer effect has recently been demonstrated in several cancer models in vitro and in vivo, but it has not been examined in the treatment of colorectal cancer.

METHODS

To elucidate the effect of atovaquone on colorectal cancer. We used RNA transcriptome sequencing, RT‒PCR and Western blot experiments to examine the expression of NF-κB (p-P65), EMT-related proteins and related inflammatory factors (IL1B, IL6, CCL20, CCL2, CXCL8, CXCL6, IL6ST, FAS, IL10 and IL1A). The effect of atovaquone on colorectal cancer metastasis was validated using an animal model of lung metastases. We further used transcriptome sequencing, the GCBI bioinformatics database and the STRING database to predict relevant target proteins. Furthermore, pathological sections were collected from relevant cases for immunohistochemical verification.

RESULTS

This study showed that atovaquone could inhibit colorectal cancer metastasis and invasion in vivo and in vitro, inhibit the expression of E-cadherin protein, and promote the protein expression of N-cadherin, vimentin, ZEB1, Snail and Slug. Atovaquone could inhibit EMT by inhibiting NF-κB (p-P65) and related inflammatory factors. Further bioinformatics analysis and verification showed that PDGFRβ was one of the targets of atovaquone.

CONCLUSION

In summary, atovaquone can inhibit the expression of NF-κB (p-P65) and related inflammatory factors by inhibiting the protein expression of p-PDGFRβ, thereby inhibiting colorectal cancer metastasis. Atovaquone may be a promising drug for the treatment of colorectal cancer metastasis.

Effects of 1-year tofacitinib therapy on angiogenic biomarkers in rheumatoid arthritis

OBJECTIVES

Cardiovascular (CV) morbidity and mortality, and perpetuated synovial angiogenesis have been associated with RA. In our study we evaluated angiogenic factors in relation to vascular inflammation and function, and clinical markers in RA patients undergoing 1-year tofacitinib therapy.

METHODS

Thirty RA patients treated with either 5 mg or 10 mg twice daily tofacitinib were included in a 12-month follow-up study. Eventually, 26 patients completed the study and were included in data analysis. Levels of various angiogenic cytokines (TNF-α, IL-6), growth factors [VEGF, basic fibroblast (bFGF), epidermal (EGF), placental (PlGF)], cathepsin K (CathK), CXC chemokine ligand 8 (CXCL8), galectin-3 (Gal-3) and N-terminal prohormone brain natriuretic peptide (NT-proBNP) were determined at baseline, and at 6 and 12 months after initiating tofacitinib treatment. In order to assess flow-mediated vasodilation, common carotid intima-media thickness (ccIMT) and carotid-femoral pulse-wave velocity, ultrasonography was performed. Synovial and aortic inflammation was also assessed by 18F-fluorodeoxyglucose-PET/CT.

RESULTS

One-year tofacitinib therapy significantly decreased IL-6, VEGF, bFGF, EGF, PlGF and CathK, while it increased Gal-3 production (P < 0.05). bFGF, PlGF and NT-proBNP levels were higher, while platelet-endothelial cell adhesion molecule 1 (PECAM-1) levels were lower in RF-seropositive patients (P < 0.05). TNF-α, bFGF and PlGF correlated with post-treatment synovial inflammation, while aortic inflammation was rather dependent on IL-6 and PECAM-1 as determined by PET/CT (P < 0.05). In the correlation analyses, NT-proBNP, CXCL8 and Cath variables correlated with ccIMT (P < 0.05).

CONCLUSIONS

Decreasing production of bFGF, PlGF or IL-6 by 1-year tofacitinib therapy potentially inhibits synovial and aortic inflammation. Although NT-proBNP, CXCL8 and CathK were associated with ccIMT, their role in RA-associated atherosclerosis needs to be further evaluated.

Cellular and molecular mechanisms in vascular repair after traumatic brain injury: a narrative review

Traumatic brain injury (TBI) disrupts normal brain function and is associated with high morbidity and fatality rates. TBI is characterized as mild, moderate or severe depending on its severity. The damage may be transient and limited to the dura matter, with only subtle changes in cerebral parenchyma, or life-threatening with obvious focal contusions, hematomas and edema. Blood vessels are often injured in TBI. Even in mild TBI, dysfunctional cerebral vascular repair may result in prolonged symptoms and poor outcomes. Various distinct types of cells participate in vascular repair after TBI. A better understanding of the cellular response and function in vascular repair can facilitate the development of new therapeutic strategies. In this review, we analyzed the mechanism of cerebrovascular impairment and the repercussions following various forms of TBI. We then discussed the role of distinct cell types in the repair of meningeal and parenchyma vasculature following TBI, including endothelial cells, endothelial progenitor cells, pericytes, glial cells (astrocytes and microglia), neurons, myeloid cells (macrophages and monocytes) and meningeal lymphatic endothelial cells. Finally, possible treatment techniques targeting these unique cell types for vascular repair after TBI are discussed.

Vascular Contribution to Lung Repair and Fibrosis

Lungs are constantly exposed to environmental perturbations and therefore have remarkable capacity to regenerate in response to injury. Sustained lung injuries, aging, and increased genomic instability, however, make lungs particularly susceptible to disrepair and fibrosis. Pulmonary fibrosis constitutes a major cause of morbidity and is often relentlessly progressive, leading to death from respiratory failure. The pulmonary vasculature, which is critical for gas exchanges and plays a key role during lung development, repair, and regeneration, becomes aberrantly remodeled in patients with progressive pulmonary fibrosis. Although capillary rarefaction and increased vascular permeability are recognized as distinctive features of fibrotic lungs, the role of vasculature dysfunction in the pathogenesis of pulmonary fibrosis has only recently emerged as an important contributor to the progression of this disease. This review summarizes current findings related to lung vascular repair and regeneration and provides recent insights into the vascular abnormalities associated with the development of persistent lung fibrosis.

Antiangiogenic potential of Lepista nuda extract suppressing MAPK/p38 signaling-mediated developmental angiogenesis in zebrafish and HUVECs

The medicinal properties of natural/edible plant products and their use are popular in traditional practice owing to their nutritional contents with little to no side effects. Lepista nuda (L. nuda), an edible mushroom (Clitocybe nuda, commonly known as blewit), has attracted researchers to evaluate its contents and the mechanism of its activities. In the current study, we focused on evaluating the antiangiogenic effects of L. nuda water extract on zebrafish development and in vitro human umbilical vein endothelial cell (HUVEC) tube formation. Bioactive components such as ergothioneine, eritadenine, and adenosine were identified and quantified by HPLC analysis. The L. nuda extract showed antiangiogenic properties and inhibited intersegmental vessel (ISV), caudal vein plexus (CVP), hyaloid vessel (HV), and subintestinal vessel (SIV) development in Tg (fli1: EGFP) zebrafish embryos. The expression of angiogenesis-related genes (vegfaa, kdrl, vegfba, flt1, kdr) was affected following L. nuda extract treatment. L. nuda extract attenuated in vitro HUVEC tube formation, migration, and invasion. Furthermore, inhibition of MAPK/p38 signaling and depletion of proangiogenic genes, including growth factors (fgf, ang2, and vegfa); primary and accessory receptors (tie2, vegfr2, and eng); MMPs (mmp1 and mmp2); and cytokines (il-1α, il-1β, il-6, and tnf-α) was observed in HUVECs following L. nuda treatment. An in vivo zebrafish xenograft assay showed that L. nuda extract inhibited HuCCT1 cell-induced SIV sprouting in HuCCT1-injected embryos. Collectively, the results suggest that L. nuda could be a potential inhibitor of angiogenesis limiting cancer progression.

Inhalant cannabidiol impedes tumor growth through decreased tumor stemness and impaired angiogenic switch in NCI-H1437-induced human lung cancer model

Lung cancer remains the most chronic form of cancer and the leading cause of cancer mortality in the world. Despite significant improvements in the treatment of lung cancer, the current therapeutic interventions are only partially effective, necessitating the continued search for better, novel alternative treatments. Angiogenesis and cancer stem cells play a central role in the initiation and propagation of cancers. Tumor angiogenesis is triggered by an angiogenic switch when pro-angiogenic factors exceed anti-angiogenic components. Although many anti-angiogenic agents are used in cancer treatment, there are therapeutic limitations with significant side effects. In recent years, cannabinoids have been investigated extensively for their potential anti-neoplastic effects. Our previous findings showed that cannabidiol (CBD) could impede tumor growth in mouse models of melanoma and glioblastoma. Importantly, CBD has been suggested to possess anti-angiogenic activity. In this study, we tested, for the first time, inhalant CBD in the treatment of heterotopic lung cancer and whether such potential effects could reduce cancer stem cell numbers and inhibit tumor angiogenesis. We implanted NCI H1437 human lung cancer cells in nude mice and treated the mice with inhalant CBD or placebo. The outcomes were measured by tumor size and imaging, as well as by immunohistochemistry and flow cytometric analysis for CD44, VEGF, and P-selectin. Our findings showed that CBD decreased tumor growth rate and suppressed expression of CD44 and the angiogenic factors VEGF and P-selectin. These results suggest, for the first time, that inhalant CBD can impede lung cancer growth by suppressing CD44 and angiogenesis.

Recent Developments in the Study of the Microenvironment of Cancer and Drug Delivery

Cancer is characterized by disrupted molecular variables caused by cells that deviate from regular signal transduction. The uncontrolled segment of such cancerous cells annihilates most of the tissues that contact them. Gene therapy, immunotherapy, and nanotechnology advancements have resulted in novel strategies for anticancer drug delivery. Furthermore, diverse dispersion of nanoparticles in normal stroma cells adversely affects the healthy cells and disrupts the crosstalk of tumour stroma. It can contribute to cancer cell progression inhibition and, conversely, to acquired resistance, enabling cancer cell metastasis and proliferation. The tumour's microenvironment is critical in controlling the dispersion and physiological activities of nano-chemotherapeutics which is one of the targeted drug therapy. As it is one of the methods of treating cancer that involves the use of medications or other substances to specifically target and kill off certain subsets of malignant cells. A targeted therapy may be administered alone or in addition to more conventional methods of care like surgery, chemotherapy, or radiation treatment. The tumour microenvironment, stromatogenesis, barriers and advancement in the drug delivery system across tumour tissue are summarised in this review.

Chemokines and NSCLC: Emerging role in prognosis, heterogeneity, and therapeutics

Lung cancer persists to contribute to one-quarter of cancer-associated deaths. Among the different histologies, non-small cell lung cancer (NSCLC) alone accounts for 85% of the cases. The development of therapies involving immune checkpoint inhibitors and angiogenesis inhibitors has increased patients' survival probability and reduced mortality rates. Developing targeted therapies against essential genetic alterations also translates to better treatment strategies. But the benefits still seem farfetched due to the development of drug resistance and refractory tumors. In this review, we have highlighted the interplay of different tumor microenvironment components, essentially discussing the chemokine families (CC, CXC, C, and CX3C) that regulate the tumor biology in NSCLC and promote tumor growth, metastasis, and associated heterogeneity. The development of therapeutics and prognostic markers is a complex and multipronged approach. However, some essential chemokines can act as critical players for being considered potential prognostic markers and therapeutic targets.

Correlation between Cancer Stem Cells, Inflammation and Malignant Transformation in a DEN-Induced Model of Hepatic Carcinogenesis

Chronic inflammation and cancer stem cells are known risk factors for tumorigenesis. The aetiology of hepatocellular carcinoma (HCC) involves a multistep pathological process that is characterised by chronic inflammation and hepatocyte damage, but the correlation between HCC, inflammation and cancer stem cells remains unclear. In this study, we examined the role of hepatic progenitor cells in a mouse model of chemical-induced hepatocarcinogenesis to elucidate the relationship between inflammation, malignant transformation and cancer stem cells. We used diethylnitrosamine (DEN) to induce liver tumour and scored for H&E and reticulin staining. We also scored for immunohistochemistry staining for OV-6 expression and analysed the statistical correlation between them. DEN progressively induced inflammation at week 7 (40%, 2/5); week 27 (75%, 6/8); week 33 (62.5%, 5/8); and week 50 (100%, 12/12). DEN progressively induced malignant transformation at week 7 (0%, 0/5); week 27 (87.5%, 7/8); week 33 (100%, 8/8); and week 50 (100%, 12/12). The obtained data showed that DEN progressively induced high-levels of OV-6 expression at week 7 (20%, 1/5); week 27 (37.5%, 3/8); week 33 (50%, 4/8); and week 50 (100%, 12/12). DEN-induced inflammation, malignant transformation and high-level OV-6 expression in hamster liver, as shown above, as well as applying Spearman’s correlation to the data showed that the expression of OV-6 was significantly correlated to inflammation (p = 0.001) and malignant transformation (p < 0.001). There was a significant correlation between the number of cancer stem cells, inflammation and malignant transformation in a DEN-induced model of hepatic carcinogenesis in the hamster.

Noscapine, an Emerging Medication for Different Diseases: A Mechanistic Review

Noscapine is a benzylisoquinoline alkaloid isolated from poppy extract, used as an antitussive since the 1950s, and has no addictive or euphoric effects. Various studies have shown that noscapine has excellent anti-inflammatory effects and potentiates the antioxidant defences by inhibiting nitric oxide (NO) metabolites and reactive oxygen species (ROS) levels and increasing total glutathione (GSH). Furthermore, noscapine has indicated antiangiogenic and antimetastatic effects. Noscapine induces apoptosis in many cancerous cell types and provides favourable antitumour activities and inhibitory cell proliferation in solid tumours, even drug-resistant strains, via mitochondrial pathways. Moreover, this compound attenuates the dynamic properties of microtubules and arrests the cell cycle in the G2/M phase. Noscapine can reduce endothelial cell migration in the brain by inhibiting endothelial cell activator interleukin 8 (IL-8). In fact, this study aimed to elaborate on the possible mechanisms of noscapine against different disorders.

Designing biomaterials for the modulation of allogeneic and autoimmune responses to cellular implants in Type 1 Diabetes

The effective suppression of adaptive immune responses is essential for the success of allogeneic cell therapies. In islet transplantation for Type 1 Diabetes, pre-existing autoimmunity provides an additional hurdle, as memory autoimmune T cells mediate both an autoantigen-specific attack on the donor beta cells and an alloantigen-specific attack on the donor graft cells. Immunosuppressive agents used for islet transplantation are generally successful in suppressing alloimmune responses, but dramatically hinder the widespread adoption of this therapeutic approach and fail to control memory T cell populations, which leaves the graft vulnerable to destruction. In this review, we highlight the capacity of biomaterials to provide local and nuanced instruction to suppress or alter immune pathways activated in response to an allogeneic islet transplant. Biomaterial immunoisolation is a common approach employed to block direct antigen recognition and downstream cell-mediated graft destruction; however, immunoisolation alone still permits shed donor antigens to escape into the host environment, resulting in indirect antigen recognition, immune cell activation, and the creation of a toxic graft site. Designing materials to decrease antigen escape, improve cell viability, and increase material compatibility are all approaches that can decrease the local release of antigen and danger signals into the implant microenvironment. Implant materials can be further enhanced through the local delivery of anti-inflammatory, suppressive, chemotactic, and/or tolerogenic agents, which serve to control both the innate and adaptive immune responses to the implant with a benefit of reduced systemic effects. Lessons learned from understanding how to manipulate allogeneic and autogenic immune responses to pancreatic islets can also be applied to other cell therapies to improve their efficacy and duration. STATEMENT OF SIGNIFICANCE: This review explores key immunologic concepts and critical pathways mediating graft rejection in Type 1 Diabetes, which can instruct the future purposeful design of immunomodulatory biomaterials for cell therapy. A summary of immunological pathways initiated following cellular implantation, as well as current systemic immunomodulatory agents used, is provided. We then outline the potential of biomaterials to modulate these responses. The capacity of polymeric encapsulation to block some powerful rejection pathways is covered. We also highlight the role of cellular health and biocompatibility in mitigating immune responses. Finally, we review the use of bioactive materials to proactively modulate local immune responses, focusing on key concepts of anti-inflammatory, suppressive, and tolerogenic agents.

Evaluation of gingival microcirculation in patients with gestational diabetes mellitus

OBJECTIVE

The aim of this study was to evaluate the possible microcircularity variations at periodontal mucous level in patients with gestational diabetes mellitus (GDM).

MATERIAL AND METHODS

Overall 55 periodontally healthy and non-smoker participants were enrolled in the study by whom 30 were diagnosed with GDM (26 to 34 weeks pregnant) and 25 were systemically healthy unpregnant controls. The analysis was performed in the masticatory/gingival mucosa of maxillary anterior region and by the optical probe videocapillaroscopy technique equipped with 200× lenses. The following parameters were recorded: capillary loop visibility, capillary orientation to surface, microhemorrhages, capillary density and tortuosity.

RESULTS

The average capillary density was significantly higher in participants with GDM (27 ± 5.46 no. loops/mm²) compared to controls (21.16 ± 3 no. loops/mm²) (P = 0.035) while increased tortuosity scores was observed in controls compared with the GDM group (P = 0.017). There was not any significantly difference between study groups among the other variables (P > 0.05).

CONCLUSIONS

Capillary alterations including capillary density and tortuosity were demonstrated in gingival microcirculation of patients with GDM. These microcirculatory changes could provide us new understanding on the dynamics of the relationship between GDM and periodontal tissues.

Extensive Histopathological Characterization of Inflamed Bowel in the Dextran Sulfate Sodium Mouse Model with Emphasis on Clinically Relevant Biomarkers and Targets for Drug Development

This study aims to develop a reliable and reproducible inflammatory bowel disease (IBD) murine model based on a careful spatial-temporal histological characterization. Secondary aims included extensive preclinical studies focused on the in situ expression of clinically relevant biomarkers and targets involved in IBD. C57BL/6 female mice were used to establish the IBD model. Colitis was induced by the oral administration of 2% Dextran Sulfate Sodium (DSS) for 5 days, followed by 2, 4 or 9 days of water. Histological analysis was performed by sectioning the whole colon into rings of 5 mm each. Immunohistochemical analyses were performed for molecular targets of interest for monitoring disease activity, treatment response and predicting outcome. Data reported here allowed us to develop an original scoring method useful as a tool for the histological assessment of preclinical models of DSS-induced IBD. Immunohistochemical data showed a significant increase in TNF-α, α4β7, VEGFRII, GR-1, CD25, CD3 and IL-12p40 expression in DSS mice if compared to controls. No difference was observed for IL-17, IL-23R, IL-36R or F480. Knowledge of the spatial-temporal pattern distribution of the pathological lesions of a well-characterized disease model lays the foundation for the study of the tissue expression of meaningful predictive biomarkers, thereby improving translational success rates of preclinical studies for a personalized management of IBD patients.

Angiogenesis in Adipose Tissue: The Interplay Between Adipose and Endothelial Cells

Obesity is a worldwide health problem, and as its prevalence increases, so does the burden of obesity-associated co-morbidities like type 2 diabetes or cardiovascular diseases (CVDs). Adipose tissue (AT) is an endocrine organ embedded in a dense vascular network. AT regulates the production of hormones, angiogenic factors, and cytokines. During the development of obesity, AT expands through the increase in fat cell size (hypertrophy) and/or fat cell number (hyperplasia). The plasticity and expansion of AT is related to its angiogenic capacities. Angiogenesis is a tightly orchestrated process, which involves endothelial cell (EC) proliferation, migration, invasion, and new tube formation. The expansion of AT is accelerated by hypoxia, inflammation, and structural remodeling of blood vessels. The paracrine signaling regulates the functional link between ECs and adipocytes. Adipocytes can secrete both pro-angiogenic molecules, e.g., tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), or vascular endothelial growth factor (VEGF), and anti-angiogenic factors, e.g., serpins. If the pro-angiogenic molecules dominate, the angiogenesis is dysregulated and the endothelium becomes dysfunctional. However, if anti-angiogenic molecules are overexpressed relative to the angiogenic regulators, the angiogenesis is repressed, and AT becomes hypoxic. Furthermore, in the presence of chronic nutritional excess, endothelium loses its primary function and contributes to the inflammation and fibrosis of AT, which increases the risk for CVDs. This review discusses the current understanding of ECs function in AT, the cross-talk between adipose and ECs, and how obesity can lead to its dysfunction. Understanding the interplay of angiogenesis with AT can be an approach to therapy obesity and obesity-related diseases such as CVDs.

A practical toolkit to study aspects of the metastatic cascade in vitro

While metastasis - the spread of cancer from the primary location to distant sites in the body - remains the principle cause of cancer death, it is incompletely understood. It is a complex process, requiring the metastatically successful cancer cell to negotiate a formidable series of interconnected steps, which are described in this paper. For each step, we review the range of in vitro assays that may be used to study them. We also provide a range of detailed, step-by-step protocols that can be undertaken in most modestly-equipped laboratories, including methods for converting qualitative observations into quantitative data for analysis. Assays include: (1) a gelatin degradation assay to study the ability of endothelial cells to degrade extracellular matrix during tumour angiogenesis; (2) the morphological characterisation of cells undergoing epithelial-mesenchymal transition (EMT) as they acquire motility; (3) a 'scratch' or 'wound-healing' assay to study cancer cell migration; (4) a transwell assay to study cancer cell invasion through extracellular matrix; and (5) a static adhesion assay to examine cancer cell interactions with, and adhesion to, endothelial monolayers. This toolkit of protocols will enable researchers who are interested in metastasis to begin to focus on defined aspects of the process. It is only by further understanding this complex, fascinating and clinically relevant series of events that we may ultimately devise ways of better treating, or even preventing, cancer metastasis. The assays may also be of more broad interest to researchers interested in studying aspects of cellular behaviour in relation to other developmental and disease processes.

Targeted inhibition of endothelial calpain delays wound healing by reducing inflammation and angiogenesis

Wound healing is a multistep phenomenon that relies on complex interactions between various cell types. Calpains are a well-known family of calcium-dependent cysteine proteases that regulate several processes, including cellular adhesion, proliferation, and migration, as well as inflammation and angiogenesis. CAPNS1, the common regulatory subunit of Calpain-1 and 2, is indispensable for catalytic subunit stabilization and activity. Calpain inhibition has been shown to reduce organ damage in various disease models. Here, we report that endothelial calpain-1/2 is crucially involved in skin wound healing. Using a mouse genetic model where Capns1 is deleted only in endothelial cells, we showed that calpain-1/2 disruption is associated with reduced injury-activated inflammation, reduced CD31⁺ blood vessel density, and delayed wound healing. Moreover, in cultured HUVECs, inhibition of calpain reduced TNF-α-induced proliferation, migration, and tube formation. Deletion of Capns1 was associated with elevated levels of IκB and downregulation of β-catenin expression in endothelial cells. These observations delineate a novel mechanistic role for calpain in the crosstalk between inflammation and angiogenesis during skin repair.

IL-6 trans-Signaling Impairs Sprouting Angiogenesis by Inhibiting Migration, Proliferation and Tube Formation of Human Endothelial Cells

Sprouting angiogenesis is the formation of new capillaries from existing vessels in response to tissue hypoxia due to growth/development, repair/healing, and also chronic inflammation. In this study, we aimed to elucidate the effect of IL-6, a pleiotropic cytokine with both pro-inflammatory and anti-inflammatory functions, in regulating the sprouting angiogenic response of endothelial cells (ECs). We found that activation of IL-6 trans-signaling inhibited the migration, proliferation, and tube formation ability of ECs. In addition, inhibition of the autocrine IL-6 classic-signaling by depleting endogenous IL-6 from ECs impaired their tube formation ability. At the molecular level, we found that IL-6 trans-signaling in ECs upregulated established endogenous anti-angiogenic factors such as CXCL10 and SERPINF1 while at the same time downregulated known endogenous pro-angiogenic factors such as cKIT and CXCL8. Furthermore, prior activation of ECs by IL-6 trans-signaling alters their response to vascular endothelial growth factor-A (VEGF-A), causing an increased p38, but decreased Erk1/2 phosphorylation. Collectively, our data demonstrated the dual facets of IL-6 in regulating the sprouting angiogenic function of ECs. In addition, we shed light on molecular mechanisms behind the IL-6 trans-signaling mediated impairment of endothelial sprouting angiogenic response.

Tumor angiogenesis: causes, consequences, challenges and opportunities

Tumor vascularization occurs through several distinct biological processes, which not only vary between tumor type and anatomic location, but also occur simultaneously within the same cancer tissue. These processes are orchestrated by a range of secreted factors and signaling pathways and can involve participation of non-endothelial cells, such as progenitors or cancer stem cells. Anti-angiogenic therapies using either antibodies or tyrosine kinase inhibitors have been approved to treat several types of cancer. However, the benefit of treatment has so far been modest, some patients not responding at all and others acquiring resistance. It is becoming increasingly clear that blocking tumors from accessing the circulation is not an easy task to accomplish. Tumor vessel functionality and gene expression often differ vastly when comparing different cancer subtypes, and vessel phenotype can be markedly heterogeneous within a single tumor. Here, we summarize the current understanding of cellular and molecular mechanisms involved in tumor angiogenesis and discuss challenges and opportunities associated with vascular targeting.

Human PRPF40B regulates hundreds of alternative splicing targets and represses a hypoxia expression signature

Altered splicing contributes to the pathogenesis of human blood disorders including myelodysplastic syndromes (MDS) and leukemias. Here we characterize the transcriptomic regulation of PRPF40B, which is a splicing factor mutated in a small fraction of MDS patients. We generated a full PRPF40B knockout (KO) in the K562 cell line by CRISPR/Cas9 technology and rescued its levels by transient overexpression of wild-type (WT), P383L or P540S MDS alleles. Using RNA sequencing, we identified hundreds of differentially expressed genes and alternative splicing (AS) events in the KO that are rescued by WT PRPF40B, with a majority also rescued by MDS alleles, pointing to mild effects of these mutations. Among the PRPF40B-regulated AS events, we found a net increase in exon inclusion in the KO, suggesting that this splicing factor primarily acts as a repressor. PRPF40B-regulated splicing events are likely cotranscriptional, affecting exons with A-rich downstream intronic motifs and weak splice sites especially for 5' splice sites, consistent with its PRP40 yeast ortholog being part of the U1 small nuclear ribonucleoprotein. Loss of PRPF40B in K562 induces a KLF1 transcriptional signature, with genes involved in iron metabolism and mainly hypoxia, including related pathways like cholesterol biosynthesis and Akt/MAPK signaling. A cancer database analysis revealed that PRPF40B is lowly expressed in acute myeloid leukemia, whereas its paralog PRPF40A expression is high as opposed to solid tumors. Furthermore, these factors negatively or positively correlated with hypoxia regulator HIF1A, respectively. Our data suggest a PRPF40B role in repressing hypoxia in myeloid cells, and that its low expression might contribute to leukemogenesis.

The role of enteric neurons in the development and progression of colorectal cancer

The enteric nervous system (ENS) is the intrinsic neural network of the gastrointestinal tract, which is essential for regulating gut functions and intestinal homeostasis. The importance of the ENS is underscored by the existence of severe gastrointestinal diseases, such as Hirschsprung's disease and intestinal pseudo-obstruction, which arise when the ENS fails to develop normally or becomes dysregulated. Moreover, it is known that enteric neurons are involved in intestinal inflammation. However, the role of the ENS in colorectal cancer (CRC) carcinogenesis remains poorly understood, even though processes like perineural invasion and neoneurogenesis are important factors in CRC. Here we summarize how enteric neurons are affected during CRC and discuss the influence of enteric neurons, either direct or indirect, on the development and/or progression of CRC. Finally, we illustrate how the ENS could be targeted as a potential anti-cancer therapy, establishing the ENS as an integral part of the tumor microenvironment.

Effect of Niacin on Inflammation and Angiogenesis in a Murine Model of Ulcerative Colitis

Butyrate and niacin are produced by gut microbiota, however butyrate has received most attention for its effects on colonic health. The present study aimed at exploring the effect of niacin on experimental colitis as well as throwing some light on the ability of niacin to modulate angiogenesis which plays a crucial role of in the pathogenesis of inflammatory bowel disease. Rats were given niacin for 2 weeks. On day 8, colitis was induced by intrarectal administration of iodoacetamide. Rats were sacrificed on day 15 and colonic damage was assessed macroscopically and histologically. Colonic myeloperoxidase (MPO), tumour necrosis factor (TNF)-α, interleukin (IL)-10, vascular endothelial growth factor (VEGF), angiostatin and endostatin levels were determined. Niacin attenuated the severity of colitis as demonstrated by a decrease in weight loss, colonic wet weight and MPO activity. Iodoacetamide-induced rise in the colonic levels of TNF-α, VEGF, angiostatin and endostatin was reversed by niacin. Moreover, niacin normalized IL-10 level in colon. Mepenzolate bromide, a GPR109A receptor blocker, abolished the beneficial effects of niacin on body weight, colon wet weight as well as colonic levels of MPO and VEGF. Therefore, niacin was effective against iodoacetamide-induced colitis through ameliorating pathologic angiogenesis and inflammatory changes in a GPR109A-dependent manner.

Endothelial cells: From innocent bystanders to active participants in immune responses

The endothelium is crucially important for the delivery of oxygen and nutrients throughout the body under homeostatic conditions. However, it also contributes to pathology, including the initiation and perpetuation of inflammation. Understanding the function of endothelial cells (ECs) in inflammatory diseases and molecular mechanisms involved may lead to novel approaches to dampen inflammation and restore homeostasis. In this article, we discuss the various functions of ECs in inflammation with a focus on pathological angiogenesis, attraction of immune cells, antigen presentation, immunoregulatory properties and endothelial-to-mesenchymal transition (EndMT). We also review the current literature on approaches to target these processes in ECs to modulate immune responses and advance anti-inflammatory therapies.

Dual Therapeutic Action of a Neutralizing Anti-FGF2 Aptamer in Bone Disease and Bone Cancer Pain

Fibroblast growth factor 2 (FGF2) plays a crucial role in bone remodeling and disease progression. However, the potential of FGF2 antagonists for treatment of patients with bone diseases has not yet been explored. Therefore, we generated a novel RNA aptamer, APT-F2, specific for human FGF2 and characterized its properties in vitro and in vivo. APT-F2 blocked binding of FGF2 to each of its four cellular receptors, inhibited FGF2-induced downstream signaling and cells proliferation, and restored osteoblast differentiation blocked by FGF2. APT-F2P, a PEGylated form of APT-F2, effectively blocked the bone disruption in mouse and rat models of arthritis and osteoporosis. Treatment with APT-F2P also exerted a strong analgesic effect, equivalent to morphine, in a mouse model of bone cancer pain. These findings demonstrated dual therapeutic action of APT-F2P in bone diseases and pain, providing a promising approach to the treatment of bone diseases.

Distinct patterns of angiogenic factor expression as a predictive factor of response to chemotherapy in stage IIIA non-small-cell lung cancer patients

The expression of various angiogenic factors was assessed in tumour samples of patients with stage III non-small-cell lung cancer (NSCLC) and further evaluated in terms of response to induction paclitaxel-ifosfamide-cisplatin chemotherapy. Freshly isolated lung tumour specimens obtained by bronchoscopy from 70 stage IIIA NSCLC chemotherapy-naïve patients were sampled and analysed for vascular endothelial growth factor receptor (VEGFR)-1, VEGFR-2 and VEGFR-3. Microvessel density was assessed through evaluating the angiogenic markers CD34 and CD105. Immunostaining scores were calculated by multiplying the percentage of labeled cells by the intensity of staining for each examined parameter. The overall mean immunostaining score value from all NSCLC samples was 7.83, 5.56 and 15.86 for VEGFR-1, VEGFR-2 and VEGFR-3, respectively. The overall mean value of the endothelial antigen CD34 was 16.29, whereas the expression of the CD105 antigen in endothelial cells yielded a multivariate distribution. Patients who responded to chemotherapy expressed significantly higher VEGFR-1 and VEGFR-3 mean values compared with non-responders (P<0.001). No significant difference was noted in VEGFR-2 mean values between these two groups (P=0.06). The CD34 mean value was significantly higher in responders (P<0.001), whereas there was no significant difference in CD105 expression between the two groups (P=0.07). Angiogenic marker expression proved to be a potential predictive factor of response to chemotherapy in stage III NSCLC. which merits further investigation.

TL1A increased IL-6 production on fibroblast-like synoviocytes by preferentially activating TNF receptor 2 in rheumatoid arthritis

TNF-like protein 1A (TL1A), a member of tumor necrosis factor family, recognized as a ligand of death receptor 3 (DR3) and decoy receptor 3 (DcR3). The interaction of TL1A and DR3 may participate in the pathogenesis of some autoimmune diseases including rheumatoid arthritis (RA). Our previous results showed that high concentrations of TL1A could be found in synovial and serum in RA patients, and it was correlated with disease severity. In addition, TL1A could promote Th17 differentiation induced by TGF-β and IL-6 and increased the production of IL-17A. In the present study, we found that TL1A could promote the expression of IL-6 on fibroblast-like synoviocytes (FLS) of RA patients via NF-κB and JNK signaling pathway. TL1A-stimulated FLS increased the percentage of Th17 of peripheral blood mononuclear cells (PBMC) in RA via the production of IL-6, a critical cytokine involved in the differentiation of Th17. Moreover, the blocking of tumor necrosis factor receptor 2 (TNFR2) decreased TL1A-stimulated IL-6 production by RA FLS. Our results suggest that TL1A was capable of acting on RA FLS to elevate IL-6 expression, which promoted the production of Th17. More importantly, we showed that TL1A could influence RA FLS through binding to TNFR2 rather than DR3 on FLS, which indicated that the treatment of TNF inhibitors not only blocked the TNF but also suppressed the TL1A in RA patients.

Follicular thyroid carcinoma but not adenoma recruits tumor-associated macrophages by releasing CCL15

BACKGROUND

The differential diagnosis of follicular thyroid carcinoma (FTC) and follicular adenoma (FA) before surgery is a clinical challenge. Many efforts have been made but most focusing on tumor cells, while the roles of tumor associated macrophages (TAMs) remained unclear in FTC. Here we analyzed the differences between TAMs in FTC and those in FA.

METHODS

We first analyzed the density of TAMs by CD68 immunostaining in 59 histologically confirmed FTCs and 47 FAs. Cytokines produced by FTC and FA were profiled using antibody array, and validated by quantitative PCR. Chemotaxis of monocyte THP-1 was induced by condition medium of FTC cell lines (FTC133 and WRO82-1) with and without anti-CCL15 neutralizing antibody. Finally, we analyzed CCL15 protein level in FTC and FA by immunohistochemistry.

RESULTS

The average density of CD68(+) cells was 9.5 ± 5.4/field in FTC, significantly higher than that in FA (4.9 ± 3.4/field, p < 0.001). Subsequently profiling showed that CCL15 was the most abundant chemokine in FTC compared with FA. CCL15 mRNA in FTC was 51.4-folds of that in FA. CM of FTC cell lines induced THP-1 cell chemotaxis by 33 ~ 77%, and anti-CCL15 neutralizing antibody reduced THP-1 cell migration in a dose-dependent manner. Moreover, we observed positive CCL15 immunostaining in 67.8% of FTCs compared with 23.4% of FAs.

CONCLUSION

Our study suggested FTC might induce TAMs infiltration by producing CCL15. Measurement of TAMs and CCL15 in follicular thyroid lesions may be applied clinically to differentiate FTC from FA pre-operation.

In Vitro Assays for Endothelial Cell Functions Required for Angiogenesis: Proliferation, Motility, Tubular Differentiation, and Matrix Proteolysis

This chapter deconstructs the process of angiogenesis into its component parts in order to provide simple assays to measure discrete endothelial cell functions. The techniques described will be suitable for studying stimulators and/or inhibitors of angiogenesis and determining which aspect of the process is modulated. The assays are designed to be robust and straightforward, using human umbilical vein endothelial cells, but with an option to use other sources such as microvascular endothelial cells from various tissues or lymphatic endothelial cells. It must be appreciated that such reductionist approaches cannot cover the complexity of the angiogenic process as a whole, incorporating as it does a myriad of positive and negative signals, three-dimensional interactions with host tissues and many accessory cells including fibroblasts, macrophages, pericytes and platelets. The extent to which in vitro assays predict physiological or pathological processes in vivo (e.g., wound healing, tumor angiogenesis) or surrogate techniques such as the use of Matrigel™ plugs, sponge implants, corneal assays etc remains to be determined.

Angiogenesis in Inflammatory Bowel Disease

Angiogenesis is an important component of pathogenesis of inflammatory bowel disease (IBD). Chronic inflammation and angiogenesis are two closely related processes. Chronic intestinal inflammation is dependent on angiogenesis and this angiogenesis is modulated by immune system in IBD. Angiogenesis is a very complex process which includes multiple cell types, growth factors, cytokines, adhesion molecules, and signal transduction. Lymphangiogenesis is a new research area in the pathogenesis of IBD. While angiogenesis supports inflammation via leukocyte migration, carrying oxygen and nutrients, on the other hand, it has a major role in wound healing. Angiogenic molecules look like perfect targets for the treatment of IBD, but they have risk for serious side effects because of their nature.

Trial Watch-Immunostimulation with cytokines in cancer therapy

During the past decade, great efforts have been dedicated to the development of clinically relevant interventions that would trigger potent (and hence potentially curative) anticancer immune responses. Indeed, developing neoplasms normally establish local and systemic immunosuppressive networks that inhibit tumor-targeting immune effector cells, be them natural or elicited by (immuno)therapy. One possible approach to boost anticancer immunity consists in the (generally systemic) administration of recombinant immunostimulatory cytokines. In a limited number of oncological indications, immunostimulatory cytokines mediate clinical activity as standalone immunotherapeutic interventions. Most often, however, immunostimulatory cytokines are employed as immunological adjuvants, i.e., to unleash the immunogenic potential of other immunotherapeutic agents, like tumor-targeting vaccines and checkpoint blockers. Here, we discuss recent preclinical and clinical advances in the use of some cytokines as immunostimulatory agents in oncological indications.

Targeting of proangiogenic signalling pathways in chronic inflammation

Angiogenesis is de novo capillary outgrowth from pre-existing blood vessels. This process not only is crucial for normal development, but also has an important role in supplying oxygen and nutrients to inflamed tissues, as well as in facilitating the migration of inflammatory cells to the synovium in rheumatoid arthritis, spondyloarthritis and other systemic autoimmune diseases. Neovascularization is dependent on the balance of proangiogenic and antiangiogenic mediators, including growth factors, cytokines, chemokines, cell adhesion molecules and matrix metalloproteinases. This Review describes the various intracellular signalling pathways that govern these angiogenic processes and discusses potential approaches to interfere with pathological angiogenesis, and thereby ameliorate inflammatory disease, by targeting these pathways.

IL-37 Is a Novel Proangiogenic Factor of Developmental and Pathological Angiogenesis

OBJECTIVE

Angiogenesis is tightly controlled by growth factors and cytokines in pathophysiological settings. Interleukin 37 (IL-37) is a newly identified cytokine of the IL-1 family, some members of which are important in inflammation and angiogenesis. However, the function of IL-37 in angiogenesis remains unknown. We aimed to explore the regulatory role of IL-37 in pathological and physiological angiogenesis.

APPROACH AND RESULTS

We found that IL-37 was expressed and secreted in endothelial cells and upregulated under hypoxic conditions. IL-37 enhanced endothelial cell proliferation, capillary formation, migration, and vessel sprouting from aortic rings with potency comparable with that of vascular endothelial growth factor. IL-37 activates survival signals including extracellular signal-regulated kinase 1/2 and AKT in endothelial cells. IL-37 promoted vessel growth in implanted Matrigel plug in vivo in a dose-dependent manner with potency comparable with that of basic fibroblast growth factor. In the mouse model of retinal vascular development, neonatal mice administrated with IL-37 displayed increased neovascularization. We demonstrated further that IL-37 promoted pathological angiogenesis in the mouse model of oxygen-induced retinopathy.

CONCLUSIONS

Our findings suggest that IL-37 is a novel and potent proangiogenic cytokine with essential role in pathophy siological settings.

Intracellular signaling pathways involved in the release of IL-4 and VEGF from human keratinocytes by activation of kinin B1 receptor: functional relevance to angiogenesis

The injured skin produces a number of mediators that directly or indirectly modulate cell chemotaxis, migration, proliferation, and angiogenesis. Components of the kinin pathway including the kinin B1 receptor (B1R) have been found to occur in the human skin, but information about its role on keratinocyte biology is still scarce. Our aim was to determine whether stimulation of B1R causes the secretion of IL-4 and/or VEGF from human keratinocytes and to evaluate the role of the B1R agonist Lys-des[Arg(9)]bradykinin and IL-4 on various stages of angiogenesis, such as cell migration, proliferation, and release of metalloproteases. By using ELISA and Western blotting, we showed that HaCaT keratinocytes stimulated with the B1R agonist release IL-4 and VEGF. Stimulation of B1R also caused transient c-JunN-terminal kinase phosphorylation and JunB nuclear translocation, transcription factor that regulates IL-4 expression. The 3D-angiogenesis assay, performed on spheroids of EA.hy923 endothelial cells embedded in a collagen matrix, showed that their cumulative sprout area increased significantly following stimulation with either IL-4 or B1R agonist. Furthermore, these ligands produced significant endothelial cell migration and release of metalloproteases 2 and 9, but did not increase endothelial cell proliferation as measured by 5-bromo-2'-deoxyuridine incorporation. Our results provide experimental evidence that establishes IL-4 and B1R agonist as important angiogenic factors of relevance for skin repair.

Role of Chemokines in Non-Small Cell Lung Cancer: Angiogenesis and Inflammation

Non-small cell lung cancer (NSCLC) is one of the most common types of aggressive cancer. The tumor tissue, which shows an active angiogenesis, is composed of neoplastic and stromal cells, and an abundant inflammatory infiltrate. Angiogenesis is important to support tumor growth, while infiltrating cells contribute to the tumor microenvironment through the secretion of growth factors, cytokines and chemokines, important molecules in the progression of the disease. Chemokines are important in development, activation of the immune response, and physiological angiogenesis. Chemokines have emerged as important regulators in the pathophysiology of cancer. These molecules are involved in the angiogenesis/angiostasis balance and in the recruitment of tumor infiltrating hematopoietic cells. In addition, chemokines promote tumor cell survival, as well as the directing and establishment of tumor cells to metastasis sites. The findings summarized here emphasize the central role of chemokines as modulators of tumor angiogenesis and their potential role as therapeutic targets in the inflammatory process of NSCLC angiogenesis.

Absence of multiple atypical chemokine binders (ACBs) and the presence of VEGF and MMP-9 predict axillary lymph node metastasis in early breast carcinomas

The aim of this study was to determine the frequency of axillary lymph node (ALN) metastasis of early breast cancers by evaluating the status of DARC, D6 and CCX-CKR and the levels of VEGF and MMP-9. The status of DARC, D6 and CCX-CKR and the levels VEGF and MMP-9 were evaluated in ALN- (n = 130) and ALN + (n = 88) patients with T1 breast cancer by immunohistochemical staining. For ALN, likelihood ratio χ (2)-tests were used for univariate analysis and logistic regression for multivariate analysis. Univariate analysis identified the nuclear grade, VEGF and MMP-9 expression and absence of DARC, D6 and CCX-CKR as predictors of ALN involvement. When combining the three receptors (DARC, D6 and CCX-CKR) together, tumors with multiple absence (multi-absence, any two or three loss) had a higher likelihood of being ALN positive than non-multi-absence (coexpression of any two or three) tumors (56.2 vs. 27.9 %, P < 0.001). The final multivariate logistic regression revealed nuclear grade, VEGF, MMP-9 and non-multi-absence versus multi-absence to be independent predictors of ALN involvement; the odds ratio (OR) and 95 % CI for non-multi-absence tumors versus multi-absence were 0.469 (0.233-0.943). Multi-absence was also associated with the involvement of four or more lymph nodes among ALN + tumors. Moreover, tumors with multi-absence had higher VEGF (78.1 vs. 50.0 %, P < 0.001) and MMP-9 (81.3 vs. 36.1 %, P < 0.001) expression than non-multi-absence tumors. Our data highlight that the absence of DARC, D6 and CCX-CKR in combination, which is associated with higher VEGF and MMP-9 expression, predicts the presence and extent of ALN metastasis in breast cancer.

Orchestration of angiogenesis by immune cells

It is widely accepted that the tumor microenvironment (TUMIC) plays a major role in cancer and is indispensable for tumor progression. The TUMIC involves many "players" going well beyond the malignant-transformed cells, including stromal, immune, and endothelial cells (ECs). The non-malignant cells can acquire tumor-promoting functions during carcinogenesis. In particular, these cells can "orchestrate" the "symphony" of the angiogenic switch, permitting the creation of new blood vessels that allows rapid expansion and progression toward malignancy. Considerable attention within the context of tumor angiogenesis should focus not only on the ECs, representing a fundamental unit, but also on immune cells and on the inflammatory tumor infiltrate. Immune cells infiltrating tumors typically show a tumor-induced polarization associated with attenuation of anti-tumor functions and generation of pro-tumor activities, among these angiogenesis. Here, we propose a scenario suggesting that the angiogenic switch is an immune switch arising from the pro-angiogenic polarization of immune cells. This view links immunity, inflammation, and angiogenesis to tumor progression. Here, we review the data in the literature and seek to identify the "conductors" of this "orchestra." We also suggest that interrupting the immune → inflammation → angiogenesis → tumor progression process can delay or prevent tumor insurgence and malignant disease.

A prognostic classifier consisting of 17 circulating cytokines is a novel predictor of overall survival for metastatic colorectal cancer patients

We aimed to determine the prognostic values of 39 circulating cytokines in Chinese patients with metastatic colorectal cancer (CRC) and to develop a novel cytokine-based prognostic classifier (CBPC) for prognostic prediction. A total of 176 patients were divided into two cohorts based on the date of first-line chemotherapy. The first 99 cases were assigned to the training cohort, and the remaining 77 cases were assigned to the validation cohort. Thirty-nine cytokines were simultaneously analyzed in the patient serum samples using multiplex bead-based Luminex technology. We used support vector machine-based methods and Cox proportional hazards models to develop a CBPC from the training cohort, which we then validated using the second patient cohort. Univariate analysis showed that FGF-2, TGFα, Flt-3L, GM-CSF, INFα2, GRO, IL-10, MCP-3, MDC, sIL-2Rα, IL-2, IL-7, IL-8, MCP-1, MIP-1β, TNFα and VEGF were significant risk factors affecting the overall survival (OS) of both the training cohort and the validation cohort. We developed a CBPC to predict the OS of metastatic CRC patients using these 17 cytokines (sensitivity, 0.835; specificity, 0.800). In the validation cohort, the CBPC was found to have significant power in predicting the OS of metastatic CRC patients. Our study showed that there were significant associations between cytokine expression and prognosis of the patients with metastatic CRC. The CBPC that we developed includes multiple circulating cytokines and may serve as a novel screening tool for identifying metastatic CRC patients with a high risk of short OS. These high-risk individuals may also be suitable for cytokine-targeted therapies.

Antioxidants and human diseases

Oxidative stress plays a pivotal role in the development of human diseases. Reactive oxygen species (ROS) that includes hydrogen peroxide, hyphochlorus acid, superoxide anion, singlet oxygen, lipid peroxides, hypochlorite and hydroxyl radical are involved in growth, differentiation, progression and death of the cell. They can react with membrane lipids, nucleic acids, proteins, enzymes and other small molecules. Low concentrations of ROS has an indispensable role in intracellular signalling and defence against pathogens, while, higher amounts of ROS play a role in number of human diseases, including arthritis, cancer, diabetes, atherosclerosis, ischemia, failures in immunity and endocrine functions. Antioxidants presumably act as safeguard against the accumulation of ROS and their elimination from the system. The aim of this review is to highlight advances in understanding of the ROS and also to summarize the detailed impact and involvement of antioxidants in selected human diseases.

Trial watch: Immunostimulatory cytokines in cancer therapy

Tumor-targeting immune responses provide a significant contribution to (when they do not entirely account for) the clinical activity of diverse antineoplastic regimens, encompassing not only a large panel of immunotherapeutic strategies but also conventional cytotoxic molecules, targeted anticancer agents and irradiation. In line with this notion, several approaches have been devised to elicit novel or boost existing anticancer immune responses, including the administration of immunomodulatory cytokines. Such a relatively unspecific intervention suffices to mediate clinical effects in (at least a subset of) patients bearing particularly immunogenic tumors, like melanoma and renal cell carcinoma. More often, however, immunostimulatory cytokines are administered to boost the immunogenic potential of other agents, including (but not limited to) immune checkpoint-blocking antibodies, anticancer vaccines, oncolytic viruses and immunogenic chemotherapeutics. Here, we summarize the latest advances in the clinical development of recombinant cytokines as an immunomodulatory intervention for cancer therapy.

Effects of sesquiterpene, flavonoid and coumarin types of compounds from Artemisia annua L. on production of mediators of angiogenesis

BACKGROUND

In addition to recognized antimalarial effects, Artemisia annua L. (Qinghao) possesses anticancer properties. The underlying mechanisms of this activity are unknown. The aim of our experiments was to investigate the effects of distinct types of compounds isolated from A. annua on the immune-activated production of major mediators of angiogenesis playing a crucial role in growth of tumors and formation of metastasis.

METHODS

Included in the study were the sesquiterpene lactones artemisinin and its biogenetic precursors arteannuin B and artemisinic acid. The semi-synthetic analogue dihydroartemisinin was used for comparative purposes. The flavonoids were represented by casticin and chrysosplenol D, the coumarin type of compounds by 4-methylesculetin. Their effects on the lipopolysaccharide (LPS)-induced in vitro production of nitric oxide (NO) were analyzed in rat peritoneal cells using Griess reagent. The LPS-activated production of prostaglandin E2 (PGE2) and cytokines (VEGF, IL-1β, IL-6 and TNF-α) was determined in both rat peritoneal cells and human peripheral blood mononuclear cells using ELISA.

RESULTS

All sesquiterpenes (artemisinin, dihydroartemisinin, artemisinic acid, arteannuin B) significantly reduced production of PGE2. Arteannuin B also inhibited production of NO and secretion of cytokines. All NO, PGE2 and cytokines were suppressed by flavonoids casticin and chrysosplenol D. The coumarin derivative, 4-methylesculetin, was ineffective to change the production of any of these factors.

CONCLUSIONS

The inhibition of immune mediators of angiogenesis by sesquiterpene lactones and flavonoids may be one of the mechanisms of anticancer activity of Artemisia annua L.

The potential role of angiogenic factors in rheumatoid arthritis

Angiogenesis is an important phenomenon in the pathogenesis of some diseases, such as numerous types of tumors and autoimmunity, and also a number of soluble and cell-bound factors may stimulate neovascularization in inflammatory reaction processes. Here, by highlighting the significance of angiogenesis reaction in rheumatoid arthritis (RA), we will mainly focus on the role of various growth factors, cytokines, enzymes, cells, hypoxic conditions and transcription factors in the angiogenic process and we will then explain some therapeutic strategies based on blockage of angiogenesis and modification of the vascular pathology in RA.

Phosphorylated VEGFR2 and hypertension: potential biomarkers to indicate VEGF-dependency of advanced breast cancer in anti-angiogenic therapy

The efficacy of anti-VEGF agents probably lies on VEGF-dependency. Apatinib, a specific tyrosine kinase inhibitor that targets VEGF receptor 2, was assessed in patients with advanced breast cancer (ABC) (ClinicalTrials.gov NCT01176669 and NCT01653561). This substudy was to explore the potential biomarkers for VEGF-dependency in apatinib-treated breast cancer. Eighty pretreated patients received apatinib 750 or 500 mg/day orally in 4-week cycles. Circulating biomarkers were measured using a multiplex assay, and tissue biomarkers were identified with immunostaining. Baseline characteristics and adverse events (AEs) were included in the analysis. Statistical confirmation of independent predictive factors for anti-tumor efficacy was performed using Cox and Logistic regression models. Median progression-free survival (PFS) was 3.8 months, and overall survival (OS) was 10.6 months, with 17.5 % of objective response rate. Prominent AEs (≥60 %) were hypertension, hand-foot skin reaction (HFSR), and proteinuria. Higher tumor phosphorylated VEGFR2 (p-VEGFR2) expressions (P = 0.001), higher baseline serum soluble VEGFR2 (P = 0.031), hypertension (P = 0.011), and HFSR (P = 0.018) were significantly related to longer PFS, whereas hypertension (P = 0.002) and HFSR (P = 0.001) were also related to OS. Based on multivariate analysis, only p-VEGFR2 (adjusted HR, 0.40; P = 0.013) and hypertension (adjusted HR, 0.58; P = 0.038) were independent predictive factors for both PFS and clinical benefit rate. Apatinib had substantial antitumor activity in ABC and manageable toxicity. p-VEGFR2 and hypertension may be surrogate predictors of VEGF-dependency of breast cancer, which may identify an anti-angiogenesis sensitive population.

Pulmonary oxidative stress, inflammation and cancer: respirable particulate matter, fibrous dusts and ozone as major causes of lung carcinogenesis through reactive oxygen species mechanisms

Reactive oxygen or nitrogen species (ROS, RNS) and oxidative stress in the respiratory system increase the production of mediators of pulmonary inflammation and initiate or promote mechanisms of carcinogenesis. The lungs are exposed daily to oxidants generated either endogenously or exogenously (air pollutants, cigarette smoke, etc.). Cells in aerobic organisms are protected against oxidative damage by enzymatic and non-enzymatic antioxidant systems. Recent epidemiologic investigations have shown associations between increased incidence of respiratory diseases and lung cancer from exposure to low levels of various forms of respirable fibers and particulate matter (PM), at occupational or urban air polluting environments. Lung cancer increases substantially for tobacco smokers due to the synergistic effects in the generation of ROS, leading to oxidative stress and inflammation with high DNA damage potential. Physical and chemical characteristics of particles (size, transition metal content, speciation, stable free radicals, etc.) play an important role in oxidative stress. In turn, oxidative stress initiates the synthesis of mediators of pulmonary inflammation in lung epithelial cells and initiation of carcinogenic mechanisms. Inhalable quartz, metal powders, mineral asbestos fibers, ozone, soot from gasoline and diesel engines, tobacco smoke and PM from ambient air pollution (PM₁₀ and PM₂.₅) are involved in various oxidative stress mechanisms. Pulmonary cancer initiation and promotion has been linked to a series of biochemical pathways of oxidative stress, DNA oxidative damage, macrophage stimulation, telomere shortening, modulation of gene expression and activation of transcription factors with important role in carcinogenesis. In this review we are presenting the role of ROS and oxidative stress in the production of mediators of pulmonary inflammation and mechanisms of carcinogenesis.

Chemokines mRNA expression in relation to the Macrophage Migration Inhibitory Factor (MIF) mRNA and Vascular Endothelial Growth Factor (VEGF) mRNA expression in the microenvironment of endometrial cancer tissue and normal endometrium: a pilot study

Tumor microenvironment inflammatory cells play a major role in cancer progression. Among these, the Tumor Associated Macrophages (TAMs) infiltration depends on the kind of chemokine, cytokines and growth factors secreted by the tumor cells and by the stroma in response to the cancer invasion. TAMs have been found to promote anti-tumor response in early stages and to stimulate neovascularization and metastases in advanced disease. In the microenvironment chemo-attractants of many human cancers, MIF and VEGF correlate with an increased TAMs recruitment. In addition, MIF enhances tumor cells metastases by modulating the immune responses and by promoting the angiogenesis related to VEGF. On the contrary the inhibition of MIF can lead to cell cycle arrest and apoptosis. Some chemokines (e.g. CXCL12, CXCL11, CXCL8) and their receptors, thanks to their ability to modulate migration and proliferation, are involved in the angiogenetic process. In this study we compared the expression of MIF mRNA with VEGF mRNA expression and with mRNA expression of other chemokines related to neo-angiogenesis, such as CXCL12, CXCL11, CXCL8 and CXCR4, in human endometrial cancer tissue (EC) and normal endometrium (NE). Fresh samples of EC tissue and NE were extracted from 15 patients with FIGO stage I-III undergoing primary surgery. Some of the tissue was sent for histology and part of it was treated with RNA later and stored at -80°C. Four patients dropped out. A significant up-regulation of MIF mRNA in EC tissue versus NE samples (P=0.01) was observed in all 11 patients. The MIF mRNA over-expression was coincident with a VEGF mRNA overexpression in 54% of patients (P=NS). MIF mRNA was inversely related to CXCL12 mRNA expression (P=0.01). MIF over-expression was significantly related to low grading G1-2 (P=0.01), endometrial type I (P=0.05), no lymphovascular spaces invasion (P=0.01) and 3years DFS (P=0.01). As reported in previous studies on patients with breast cancer, our data suggest that the up-regulation of MIF in patients with endometrial cancer might be related to the inhibition of distant and lymphatic spread.

Differential expression of capillary VEGF isoforms following traumatic brain injury

OBJECTIVES

While it is known that angiogenesis occurs after trauma, we sought to characterize the expression of vascular endothelial growth factor (VEGF) subtypes, vascular endothelial growth factor receptor 2 (VEGFR2) and angiopoietin within capillaries of animals subjected to traumatic brain injury (TBI). Further, we sought to characterize pericyte cell death in isolated capillaries.

METHODS

We used Marmarou's acceleration impact model to induce head trauma and measured VEGF, VEGFR2 and angiopoietin levels in isolated capillaries. TUNEL was used to determine pericyte cell death.

RESULTS

The VEGF response was restricted to the VEGF120 isoform. No increase in transcripts for VEGF164 and VEGF188 was observed. VEGFR2 was marginally increased and angiopoietin was increased. A subset of pericytes were TUNEL-positive.

DISCUSSION

These results show a distinct expression pattern of angiogenic factors following injury and suggest that pericyte involvement in adaptive angiogenesis may be altered following TBI.