PlGF/VEGFR-1 Signaling Promotes Macrophage Polarization and Accelerated Tumor Progression in Obesity

PURPOSE

Obesity promotes pancreatic and breast cancer progression via mechanisms that are poorly understood. Although obesity is associated with increased systemic levels of placental growth factor (PlGF), the role of PlGF in obesity-induced tumor progression is not known. PlGF and its receptor VEGFR-1 have been shown to modulate tumor angiogenesis and promote tumor-associated macrophage (TAM) recruitment and activity. Here, we hypothesized that increased activity of PlGF/VEGFR-1 signaling mediates obesity-induced tumor progression by augmenting tumor angiogenesis and TAM recruitment/activity.

EXPERIMENTAL DESIGN

We established diet-induced obese mouse models of wild-type C57BL/6, VEGFR-1 tyrosine kinase (TK)-null, or PlGF-null mice, and evaluated the role of PlGF/VEGFR-1 signaling in pancreatic and breast cancer mouse models and in human samples.

RESULTS

We found that obesity increased TAM infiltration, tumor growth, and metastasis in pancreatic cancers, without affecting vessel density. Ablation of VEGFR-1 signaling prevented obesity-induced tumor progression and shifted the tumor immune environment toward an antitumor phenotype. Similar findings were observed in a breast cancer model. Obesity was associated with increased systemic PlGF, but not VEGF-A or VEGF-B, in pancreatic and breast cancer patients and in various mouse models of these cancers. Ablation of PlGF phenocopied the effects of VEGFR-1-TK deletion on tumors in obese mice. PlGF/VEGFR-1-TK deletion prevented weight gain in mice fed a high-fat diet, but exacerbated hyperinsulinemia. Addition of metformin not only normalized insulin levels but also enhanced antitumor immunity.

CONCLUSIONS

Targeting PlGF/VEGFR-1 signaling reprograms the tumor immune microenvironment and inhibits obesity-induced acceleration of tumor progression. Clin Cancer Res; 22(12); 2993-3004. ©2016 AACR.

Effect of Adipocyte Secretome in Melanoma Progression and Vasculogenic Mimicry

Obesity, favored by the modern lifestyle, acquired epidemic proportions nowadays. Obesity has been associated with various major causes of death and morbidity including malignant neoplasms. This increased prevalence has been accompanied by a worldwide increase in cutaneous melanoma incidence rates during the last decades. Obesity involvement in melanoma aetiology has been recognized, but the implicated mechanisms remain unclear. In the present study, we address this relationship and investigate the influence of adipocytes secretome on B16-F10 and MeWo melanoma cell lines. Using the 3T3-L1 adipocyte cell line, as well as ex vivo subcutaneous (SAT) and visceral (VAT) adipose tissue conditioned medium, we were able to show that adipocyte-released factors play a dual role in increasing melanoma cell overall survival, both by enhancing proliferation and decreasing apoptosis. B16-F10 cell migration and cell-cell and cell-matrix adhesion capacity were predominantly enhanced in the presence of SAT and VAT released factors. Melanocytes morphology and melanin content were also altered by exposure to adipocyte conditioned medium disclosing a more dedifferentiated phenotype of melanocytes. In addition, exposure to adipocyte-secreted molecules induced melanocytes to rearrange, on 3D cultures, into vessel-like structures, and generate characteristic vasculogenic mimicry patterns. These findings are corroborated by the released factors profile of 3T3-L1, SAT, and VAT assessed by microarrays, and led us to highlight the mechanisms by which adipose secretome from sub-cutaneous or visceral depots promote melanoma progression. J. Cell. Biochem. 117: 1697-1706, 2016. © 2015 Wiley Periodicals, Inc.

Progesterone in Breast Cancer Angiogenesis

The involvement of steroid hormones in breast carcinogenesis is well established. Recent evidence suggests that angiogenesis can be regulated by hormones. Both oestrogen and progesterone have been implicated in the angiogenic process of hormone-dependent cancers, such as breast cancer. Vascular Endothelial Growth Factor (VEGF) is a growth factor involved in angiogenesis in breast cancer that is up-regulated by estrogens. In our study we evaluated the role of progesterone in the expression of this angiogenic growth factor commonly up-regulated in breast cancer. Our findings indicate that progesterone activates an angiogenic pathway involving VEGF stimulation. The elucidation of specific angiogenic pathways promoted by progesterone can raise new therapeutic targets at least in a subset of breast cancers responsive to progesterone.

Decreased expression of neuropilin-1 as a novel key factor contributing to peripheral microvasculopathy and defective angiogenesis in systemic sclerosis

OBJECTIVES

In systemic sclerosis (SSc), vascular involvement is characterised by vascular endothelial growth factor (VEGF)-A/VEGF receptor (VEGFR) system disturbances. Neuropilin-1 (NRP1), a receptor for both class-3 semaphorins (Sema3s) and VEGF-A, is required for optimal VEGF-A/VEGFR-2 signalling. Here, we investigated the possible involvement of Sema3A/NRP1 axis in SSc.

METHODS

Circulating Sema3A and soluble NRP1 (sNRP1) were measured in patients with SSc and controls. NRP1 and Sema3A expression in skin biopsies was evaluated by immunofluorescence and western blotting. NRP1 expression was assessed in SSc and healthy dermal microvascular endothelial cells (SSc-MVECs and H-MVECs), and in SSc and control endothelial progenitor cell (EPC)-derived endothelial cells (ECs). The possible impact of transcription factor Friend leukaemia integration 1 (Fli1) deficiency on endothelial NRP1 expression was investigated by gene silencing. The binding of Fli1 to NRP1 gene promoter was evaluated using chromatin immunoprecipitation. Capillary morphogenesis was performed on Matrigel.

RESULTS

Decreased sNRP1 levels in SSc were associated with active and late nailfold videocapillaroscopy patterns and digital ulcers. No difference in Sema3A was found between patients and controls. NRP1 was significantly decreased in SSc-MVECs both ex vivo and in vitro. NRP1 and Fli1 significantly decreased in H-MVECs challenged with SSc sera, while they were not different in SSc and control EPC-derived ECs. Fli1 occupied the NRP1 gene promoter and Fli1 gene silencing reduced NRP1 expression in H-MVECs. NRP1 gene silencing in H-MVECs resulted in a significantly impaired angiogenic capacity comparable to that of cells treated with SSc sera.

CONCLUSION

In SSc, NRP1 deficiency may be an additional factor in the perturbed VEGF-A/VEGFR-2 system contributing to peripheral microvasculopathy and defective angiogenesis.

Obesity and cancer phenotype: Is angiogenesis a missed link?

Obesity remains nowadays one of the main threats to human health, being a problem of worldwide proportions. It is characterized by augmented storage of fatty acids in an enlarged adipose tissue. This process is possible thanks to a rich capillary network, supported by a mechanism that has also a crucial role on cancer: angiogenesis. Given that several studies point obesity as a risk factor for cancer development, angiogenesis may be approached as the missed link between these two pathologies. Understanding the different pathways behind angiogenesis becomes essential to break this link by developing new anti-angiogenic therapies or improving the actual ones. In the first phase, this paper will focus the structural and cellular changes that adipose tissue suffers in obesity. Then, the main pro-angiogenic players will be reviewed, taking into account the pathways that explain their putative role in obesity-cancer link. Finally, the clinical implications of the presented mechanisms will also be regarded, being the main focus on the anti-angiogenic therapies.

Abstract LB-267: Role of VEGFR-1 signaling in obesity-induced tumor progression

Background: Obesity associates with angiogenesis and increased macrophage infiltration in adipose tissues during weight gain. Whether these effects also occur in cancer to promote tumor progression in obese condition remains unclear. We have shown that the vascular endothelial growth factor receptor-1 (VEGFR-1) pathway can modulate tumor angiogenesis and recruitment of tumor-associated macrophages (TAMs). Here, we tested the emerging hypothesis that obesity enhances tumor progression and metastasis by augmenting angiogenesis and TAM recruitment via activation of the VEGFR-1 pathway.

Methods: We used a high-fat diet-induced obesity model in either wild type (WT) or VEGFR-1 tyrosine kinase null (Flt1TK-/-) C57BL/6 mice. Then, we implanted orthotopically syngeneic pancreatic (PAN02) or breast (E0771) carcinomas. We evaluated the role of VEGFR-1 activity on systemic metabolism, tumor angiogenesis and immune environment, and tumor growth and metastasis.

Results: Obesity increased p38-MAPK activation and TAM infiltration, tumor growth (p = 0.001) and metastasis (p = 0.035) in PAN02 tumors. VEGFR-1 inhibition reduced tumor growth (p = 0.007) and metastasis (p = 0.017) in obese but not lean mice. This was associated with a decreased p38-MAPK activity and a shift in TAM polarization towards the M1 phenotype with reduced secretion of pro-tumor cytokines, but no change in vascular density or number of TAMs. In the E0771 model, VEGFR-1 inhibition reduced MMP-9 expression and decreased lung metastatic burden (p = 0.026) in obese mice. In addition to these tumor effects, VEGFR-1 inhibition reduced weight gain, but caused metabolic disorder-hyperinsulinemia-during obesity. Combining metformin with VEGFR-1 inhibition not only prevented this metabolic alteration, but also by recruiting cytotoxic cells further decreased tumor growth in the PAN02 model (p = 0.047).

Conclusion: Inactivation of VEGFR-1 signaling prevents weight gain and obesity-induced acceleration of tumor progression in pancreatic and breast cancer models. Targeting VEGFR-1 signaling axis in combination with an anti-diabetic drug such as metformin might be a considerable cancer therapeutic option in the obese setting.

Note: This abstract was not presented at the meeting.

Citation Format: Joao Incio, Joshua Tam, Nuh Rahbari, Priya Suboj, Daniel McManus, Shan Chin, Trupti Vardan-Kaur, Ana Batista, Suboj Babycutty, Keehoon Jung, Anna Khachatryan, Masabumi Shibuya, Raquel Soares, Dan Duda, Rakesh K. Jain, Dai Fukumura. Role of VEGFR-1 signaling in obesity-induced tumor progression. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-267. doi:10.1158/1538-7445.AM2015-LB-267

Key endothelial cell angiogenic mechanisms are stimulated by the circulating milieu in sickle cell disease and attenuated by hydroxyurea

As hypoxia-induced inflammatory angiogenesis may contribute to the manifestations of sickle cell disease, we compared the angiogenic molecular profiles of plasma from sickle cell disease individuals and correlated these with in vitro endothelial cell-mediated angiogenesis-stimulating activity and in vivo neovascularization. Bioplex demonstrated that plasma from patients with steady-state sickle cell anemia contained elevated concentrations of pro-angiogenic factors (angiopoietin-1, basic fibroblast growth factor, vascular endothelial growth factor, vascular endothelial growth factor-D and placental growth factor) and displayed potent pro-angiogenic activity, significantly increasing endothelial cell proliferation, migration and capillary-like structure formation. In vivo neovascularization of Matrigel plugs was significantly greater in sickle cell disease mice than in non-sickle cell disease mice, consistent with an up-regulation of angiogenesis in the disease. In plasma from patients with hemoglobin SC disease without proliferative retinopathy, anti-angiogenic endostatin and thrombospondin-2 were significantly elevated. In contrast, plasma from hemoglobin SC individuals with proliferative retinopathy had a pro-angiogenic profile and more significant effects on endothelial cell proliferation and capillary formation than plasma from patients without retinopathy. Hydroxyurea therapy was associated with significant reductions in plasma angiogenic factors and inhibition of endothelial cell-mediated angiogenic mechanisms and neovascularization. Thus, individuals with sickle cell anemia or hemoglobin SC disease with retinopathy present a highly angiogenic circulating milieu, capable of stimulating key endothelial cell-mediated angiogenic mechanisms. Combination anti-angiogenic therapy to prevent the progression of unregulated neovascularization and associated manifestations in sickle cell disease, such as pulmonary hypertension, may be indicated; furthermore, the benefits and drawbacks of the potent anti-angiogenic effects of hydroxyurea should be clarified.

Surgical treatment of high-risk prostate cancer

High-risk prostate cancer (HRPC) currently comprises 17-35% of newly diagnosed cases and has the highest rate of metastasis and cancer-related death, making its management a top priority for improving prostate cancer outcomes. The definition of HRPC is not consensual and several risk stratification criteria have been used, which hinders the interpretation of data and the comparison of different studies. All classifications include prostate-specific antigen (PSA) level, biopsy Gleason score and clinical stage as criteria, but others have been added in an attempt to make stratification more accurate and clinically useful, to enable identification of the patients that can be cured by local treatment of the disease. HRPC was traditionally treated with radiotherapy (RT) and/or androgen deprivation therapy (ADT), but radical prostatectomy (RP) has slowly gained more importance in this context. This article aims to discuss the role of surgery in HRPC, highlighting the advantages of RP as primary treatment option: the ability to provide a definitive stage and grade of the cancer; allowing an early detection of treatment failure by having an undetectable PSA as treatment target; providing excellent local control of the disease; reducing the risk of metastatic progression to a greater extent than does RT. We will try to show the benefits and risks of a "surgery first" approach, keeping in mind that, despite the curative intent, a significant number of patients will still need adjuvant or salvage RT and/or ADT.

Metabolic syndrome and risk of cancer: which link?

Metabolic syndrome (MS) is characterized by a group of metabolic disturbances which lead to an enhanced risk of cardiovascular diseases and type 2 diabetes mellitus. MS constitutes a preoccupant issue with elevated prevalence in the western countries and is often related with cancer development. Elucidating the mechanisms linking these two pathologies is, therefore, essential to identify potential therapeutic molecular targets for cancer treatment in MS patients. The main goals of this review are, to identify the relation between MS and cancer development, handling specifically each one of the main players on this process: insulin and IGF system, estrogen, pro-inflammatory cytokines and others; and, given that colorectal cancer is one of the most prevalent types of cancer in MS patients, we intend to particularly highlight the mechanisms that promote colorectal cancer development in MS individuals. Finally, we will also focus on the clinical implications of the presented mechanisms on cancer therapy and care.

Fibroblast-endothelial partners for vascularization strategies in tissue engineering

Cell-based approaches have emerged as a promising therapy to achieve successful vascularization in tissue engineering. Since fibroblasts activation and migration is required for physiological events relying on angiogenesis, we hypothesize herein that different fibroblasts exhibit distinct capacity to promote capillary-like structures assembly, by mature and progenitor endothelial cells (ECs). Outgrowth endothelial cells (OECs) were isolated from human umbilical cord blood samples and characterized by immunofluorescence and imaging flow cytometry for endothelial markers. Coculture systems were established using either human umbilical vein ECs (HUVECs) or OECs with fibroblasts, being evaluated at 7, 14, and 21 days of culture. Two types of human dermal fibroblasts (HDF) were used, namely neonatal human foreskin fibroblasts-1 (HFF-1) and juvenile HDF. OECs expressed EC markers and formed capillary-like structures. HFF-1 exhibited higher expression of transglutaminase-2, while HDF exhibited a higher expression of α-smooth muscle actin (α-SMA) and podoplanin, which were not observed for HFF-1. Formation of capillary-like structures was only observed in cocultures with HDF and not with HFF-1. No significant differences were found between HDF and OECs or HUVECs cocultures. These findings suggest that HDF is a preferential cell source for promoting vascularization, either using mature or progenitor ECs, probably due to their higher expression of α-SMA and podoplanin, and increased synthesis of extracellular matrix. This work opens new research possibilities regarding the use of specific fibroblast populations cocultured with ECs, as efficient partners for vascular development in regenerative medicine strategies.

Idiopathic intracranial hypertension and oxaliplatin: a causal association?

We report a case of a 54-year-old woman presented at the emergency service with complaints of transitory visual obscurations for four days, and headache, nausea and occasional vomiting in the last two months. She had been diagnosed of colorectal cancer one year ago and she was on treatment with oxaliplatin on a FOLFOX schedule. On ophthalmic examination, the vision was of 20/20 in both eyes and bilateral disc swelling was noted. The neurologic examination was normal. Magnetic resonance revealed no changes. A diagnostic lumbar puncture demonstrated an elevated opening pressure of 290 mm H2O with normal compounds. Due to the suspicion of ocular toxicity, oxaliplatin treatment was stopped. Treatment with oral acetazolamide was started and maintained for one month. In three weeks ocular and systemic symptoms totally disappeared and disc swelling gradually improved in the following months. Ocular toxicity has been reported as an infrequent adverse effect of oxaliplatin, but intracranial idiopathic pressure has not yet been described. Findings in this case suggest that oxaliplatin could be the cause for these symptoms. As the use of oxaliplatin is increasing as first-line treatment in colorectal cancer, we have to be alert to its potential toxicity.

The independent contribution of diabetic foot ulcer on lower extremity amputation and mortality risk

AIMS

To estimate 3-year risk for diabetic foot ulcer (DFU), lower extremity amputation (LEA) and death; determine predictive variables and assess derived models accuracy.

MATERIAL AND METHODS

Retrospective cohort study including all subjects with diabetes enrolled in our diabetic foot outpatient clinic from beginning 2002 until middle 2010. Data were collected from clinical records.

RESULTS

644 subjects with mean age of 65.1 (±11.2) and diabetes duration of 16.1 (±10.8) years. Cumulative incidence was 26.6% for DFU, 5.8% for LEA and 14.0% for death. In multivariate analysis, physical impairment, peripheral arterial disease complication history, complication count and previous DFU were associated with DFU; complication count, foot pulses and previous DFU with LEA and age, complication count and previous DFU with death. Predictive models' areas under the ROC curves ranged from 0.80 to 0.83. A simplified model including previous DFU and complication count presented high accuracy. Previous DFU was associated with all outcomes, even when adjusted for complication count, in addition to more complex models.

CONCLUSIONS

DFU seems more than a marker of complication status, having independent impact on LEA and mortality risk. Proposed models may be applicable in healthcare settings to identify patients at higher risk of DFU, LEA and death.

Neonatal Human Dermal Fibroblasts Immobilized in RGD–Alginate Induce Angiogenesis

Promoting angiogenesis in a damaged tissue is a major challenge for tissue regeneration. Recent findings in tissue engineering suggest that fibroblasts (FBs) play an important role in orchestrating the angiogenic process. Fibroblasts maintain the structural integrity of connective tissue by continuously secreting growth factors and extracellular matrix precursors, which are essential for endothelial cell (EC) adhesion and spreading, thus playing a crucial role in angiogenesis. We hypothesized that FBs immobilized in alginate gels grafted with the RGD peptidic sequence could influence the recruitment of ECs to improve vascularization. In this work, the modulation of immobilized human FBs within the 3D synthetic extracellular matrix was assessed. Experiments using cocultures of ECs and FBs in indirect contact as well as angiogenic assays were performed to assess the influence of FBs immobilized in RGD–alginate in ECs' viability, stabilization, sprouting, and assembly into capillary-like structures. This study demonstrates the ability of FBs immobilized within RGD–alginate microspheres to modulate and support capillary-like structures' assembly. These findings indicate that the microenvironment created by these stromal cells in the scaffold modulates capillary morphogenesis, thus stimulating angiogenesis in situ and can potentially be used in regenerative medicine in clinical scenarios where vascularization is essential.

Cellular strategies to promote vascularisation in tissue engineering applications

Vascularisation is considered to be one of the greatest challenges in tissue engineering. Different strategies exist but cell-based approaches have emerged as a promising therapy to achieve successful vascularisation. The use of endothelial cells to engineer vascularised tissues has been extensively investigated. This field of research has evolved with the discovery of endothelial progenitor cells, a subpopulation with a high regenerative potential. However, the survival of endothelial cell populations alone seems to be impaired. To overcome this problem, co-culture systems, involving supporting cells, like mural cells, fibroblasts, or more tissue-specific cells have been developed. Endothelial cells benefit from the extracellular matrix components and growth factors produced by the supporting cells, which results in neovessel stabilisation and maturation. The use of endothelial progenitor cells in co-culture systems appears to be a promising strategy to promote vascularisation in approaches of increasing complexity. Herein, the authors provide an overview of the cellular strategies that can be used for increasing vascularisation in tissue engineering and regeneration.

Implanted neonatal human dermal fibroblasts influence the recruitment of endothelial cells in mice

The vascularization of new tissue within a reasonable time is a crucial prerequisite for the success of different cell- and material-based strategies. Considering that angiogenesis is a multi-step process involving humoral and cellular regulatory components, only in vivo assays provide the adequate information about vessel formation and the recruitment of endothelial cells. The present study aimed to investigate if neonatal human dermal fibroblasts could influence in vivo neovascularization. Results obtained showed that fibroblasts were able to recruit endothelial cells to vascularize the implanted matrix, which was further colonized by murine functional blood vessels after one week. The vessels exhibited higher levels of hemoglobin, compared with the control matrix, implanted without fibroblasts, in which no vessel formation could be observed. No significant differences were detected in systemic inflammation. The presence of vessels originated from the host vasculature suggested that host vascular response was involved, which constitutes a fundamental aspect in the process of neovascularization. Fibroblasts implanted within matrigel increased the presence of endothelial cells with positive staining for CD31 and for CD34 and the production of collagen influencing the angiogenic process and promoting the formation of microvessels. New strategies in tissue engineering could be delineated with improved angiogenesis using neonatal fibroblasts.

Schizophrenia and cancer: is angiogenesis a missed link?

Cancer prevalence and risk in schizophrenia (SZ) patients, as well as their implicated molecular pathways, is a debate that has become increasingly appreciated, despite lacking evidence. Since angiogenesis is imbalanced in both conditions, a non-systematic review of the existing literature using the PubMed database was performed to summarize current knowledge and to elucidate hypothesis regarding the reduced incidence of cancer in SZ, exploring possible angiogenesis biology aspects that can be interrelated both with SZ and cancer. Some lines of evidence based in epidemiology, genetic, molecular and biochemical studies suggest a putative interplay between SZ pathophysiology and angiogenesis, involving different molecular pathways and also influencing cancer biology. Studying angiogenesis in SZ and its implications to cancer is an unexplored field that could provide more insightful knowledge regarding its pathophysiology and promote the development of treatment applications.

Xanthohumol modulates inflammation, oxidative stress, and angiogenesis in type 1 diabetic rat skin wound healing

Type 1 diabetes mellitus is responsible for metabolic dysfunction, accompanied by chronic inflammation, oxidative stress, and endothelium dysfunction, and is often associated with impaired wound healing. Phenol-rich food improves vascular function, contributing to diabetes prevention. This study has evaluated the effect of phenol-rich beverage consumption in diabetic rats on wound healing, through angiogenesis, inflammation, and oxidative stress modulation. A wound-healing assay was performed in streptozotocin-induced diabetic Wistar rats drinking water, 5% ethanol, and stout beer with and without 10 mg/L xanthohumol (1), for a five-week period. Wounded skin microvessel density was reduced to normal values upon consumption of 1 in diabetic rats, being accompanied by decreased serum VEGF-A and inflammatory markers (IL-1β, NO, N-acetylglucosaminidase). Systemic glutathione and kidney and liver H2O2, 3-nitrotyrosine, and protein carbonylation also decreased to healthy levels after treatment with 1, implying an improvement in oxidative stress status. These findings suggest that consumption of xanthohumol (1) by diabetic animals consistently decreases inflammation and oxidative stress, allowing neovascularization control and improving diabetic wound healing.

Isoxanthohumol modulates angiogenesis and inflammation via vascular endothelial growth factor receptor, tumor necrosis factor alpha and nuclear factor kappa B pathways

Angiogenesis and inflammation are becoming distinguished players in the pathogenesis of many heterogeneous diseases, such as diabetes, cardiovascular disease, and cancer. Therefore, it is crucial to study new compounds that are able to modulate these events. Isoxanthohumol (IXN) is a polyphenol with antioxidant, anti-inflammatory, and antiangiogenic properties. The aim of this study was to evaluate the effects of IXN on blood vessel proliferation and maturation and describe underlying molecular mechanisms in endothelial cells (ECs) and vascular smooth muscle cells (VSMCs). Angiogenic profile of IXN was analyzed by retinal angiogenesis at different time points. IXN modulation of angiogenic and inflammatory signaling pathways was evaluated by Western blotting on EC and VSMC cultures. IXN inhibited by 20% sprouting angiogenesis and decreased vascular coverage by mural cells up to 39%. IXN of 10 µM also decreased inflammatory signals, namely tumor necrosis factor alpha (TNF-α) (26 and 40%) and factor nuclear kappa B (24 and 42%) in human aortic smooth muscle cells (HASMCs) and human umbilical vein endothelial cells (HUVECs). Angiogenic regulators, including vascular endothelial growth factor receptor 2 (HUVEC, 55%), angiopoietins 1 (HUVEC, 39%; HASMC, 35%), angiopoietin 2 (HUVEC, 38%), and Tie2 (HUVEC, 56%) were also inhibited by 10 µM of IXN treatments. Akt activation was reduced by 47% in HUVEC-treated cells and Erk activation was also reduced by 52 and 69% upon IXN treatment of HUVEC and HASMC. IXN seems to regulate in vivo vascular proliferation and stabilization and the EC-VSMC-inflammatory crosstalk, leaving this molecule as an interesting nutritional player for angiogenesis and inflammation-related diseases.

Increased circulating platelet microparticles as a potential biomarker in asthma

BACKGROUND

Endothelial (EMPs) and platelet microparticles (PMPs) have been studied as biomarkers in several inflammatory diseases and as central players in intercellular communication.

METHODS

In this cross-sectional study, we aimed to assess microparticle levels in asthma. Circulating microparticles and inflammatory and angiogenic markers were assessed by clinical and laboratorial evaluation, flow cytometry, and immunoassays, in a group of 20 asthmatic and 15 nonasthmatic subjects.

RESULTS

Circulating levels of PMPs (either CD31+/42b+ or CD31+/42b+/AnV+) were significantly increased in asthmatics (P = 0.021) even after adjustment for confounders. Apoptotic EMPs (CD31+/42b--/AnV+) were significantly increased before (P = 0.005) but not after adjustments (P = 0.117).

CONCLUSIONS

We propose that PMPs may be putative asthma biomarkers, playing a role in asthma pathophysiology.