Arterio-venous gradients of IL-6, plasma and serum VEGF and D-dimers in human cancer

The circulating angiogenic factors vascular endothelial growth factor-A, interleukin-6 and the fibrin D-dimer fragment were measured in the mesenteric vein, the uterine vein, as well as in peripheral venous and arterial samples in 21 randomly selected patients with operable colorectal, ovarian and cervical carcinoma. In addition, immunohistochemistry for vascular endothelial growth factor-A and interleukin-6 was performed on colorectal tumours of such patients. Serum and plasma vascular endothelial growth factor-A were not significantly elevated in the vein draining the tumours, despite tumour cell expression of vascular endothelial growth factor-A. Serum vascular endothelial growth factor-A is therefore not all tumour-derived. In contrast, serum interleukin-6 was highly elevated in the draining veins in agreement with expression of interleukin-6 in the cytoplasm of tumour cells. In the megakaryoblastic cell line MEG-01, the expression of vascular endothelial growth factor-A was found to be regulated by interleukin-6. Thus, the higher platelet vascular endothelial growth factor-A load resulting in higher serum vascular endothelial growth factor levels in cancer patients may partly result from an interleukin-6 mediated up-regulation of the expression of vascular endothelial growth factor-A in the precursor of the platelet, i.e. the megakaryocyte. We also confirmed by immunohistochemistry that platelets adhere and aggregate on tumour endothelium. We propose that interleukin-6 indirectly promotes tumour angiogenesis through its up-regulation of the vascular endothelial growth factor-A load in platelets. In addition, the correlations found between peripheral venous interleukin-6 and peripheral venous fibrinogen and D-dimers levels, and the high D-dimer levels found in the draining vein of the tumour, in agreement with fibrin deposits found in the tumour stroma, suggest an important role for interleukin-6 in extra-vascular fibrinogen metabolism. Our results suggest a pivotal role for interleukin-6 in the intrinsic link between haemostasis and angiogenesis. This might be of importance in the development of anti-angiogenic agents based on interference with haemostasis

Fibronectin and Cyclic Strain Improve Cardiac Progenitor Cell Regenerative Potential In Vitro.

Cardiac progenitor cells (CPCs) have rapidly advanced to clinical trials, yet little is known regarding their interaction with the microenvironment. Signaling cues present in the microenvironment change with development and disease. This work aims to assess the influence of two distinct signaling moieties on CPCs: cyclic biaxial strain and extracellular matrix. We evaluate four endpoints for improving CPC therapy: paracrine signaling, proliferation, connexin43 expression, and alignment. Vascular endothelial growth factor A (about 900 pg/mL) was secreted by CPCs cultured on fibronectin and collagen I. The application of mechanical strain increased vascular endothelial growth factor A secretion 2-4-fold for CPCs cultured on poly-L-lysine, laminin, or a naturally derived cardiac extracellular matrix. CPC proliferation was at least 25% higher on fibronectin than that on other matrices, especially for lower strain magnitudes. At 5% strain, connexin43 expression was highest on fibronectin. With increasing strain magnitude, connexin43 expression decreased by as much as 60% in CPCs cultured on collagen I and a naturally derived cardiac extracellular matrix. Cyclic mechanical strain induced the strongest CPC alignment when cultured on fibronectin or collagen I. This study demonstrates that culturing CPCs on fibronectin with 5% strain magnitude is optimal for their vascular endothelial growth factor A secretion, proliferation, connexin43 expression, and alignment

Evaluation of vascular endothelial growth factor A and leukemia inhibitory factor expressions at the time of implantation in diabetic rats following treatment with Metformin and Pioglitazone

Background: Implantation requires intimate crosstalk between the embryo and uterus for a successful establishment of pregnancy. Type 2 diabetes mellitus may lead to implantation failure. The effect of diabetes and its therapeutic drugs on implantation is still largely unclear. Objective: To assess the endometrial expression changes of vascular endothelial growth factor A (VEGFA) and leukemia inhibitory factor (LIF), at the time of implantation in diabetic rats following treatment with Metformin and Pioglitazone. Materials and Methods: Twenty-eight 6-8-wk-old Wistar female rats weighing 200- 250 gr were divided into four groups (n = 7/each). Type 2 diabetes was induced and Metformin and Pioglitazone were applied for 4 wk. The expression of VEGFA and LIF was measured by real-time reverse transcription-polymerase chain reaction and Western blot. Results: The relative expression of VEGFA transcript was higher in the diabetic (p = 0.02) and Metformin-treated (p = 0.04) rats compared to the control group. Furthermore, the VEGFA transcript level significantly reduced in Pioglitazone-treated diabetic rats (p = 0.03). LIF expression was elevated in the Metformin- and the Pioglitazone-treated rats and reduced in the diabetic group in comparison with the control group. Compared to the diabetic rats, the expression of LIF was significantly elevated in the Metformin- (p = 0.01) and Pioglitazone-treated (p = 0.03) groups. Conclusion: The expressions of LIF and VEGFA were altered in diabetic rats during implantation which may be associated with diabetic-related infertility. Pioglitazone is able to restore the VEGFA and LIF expressions to their baseline levels more efficiently than Metformin. Key words: Embryo implantation, Leukemia inhibitory factor, Vascular endothelial growth factor A, Metformin, Pioglitazone, Rats

Dynamic soluble changes in sVEGFR1, HGF, and VEGF promote chemotherapy and bevacizumab resistance: A prospective translational study in the BECOX (GEMCAD 09-01) trial

Despite initial responsiveness, acquired resistance to both bevacizumab and chemotherapy in metastatic colorectal cancer is universal. We have recently published that in vitro, chronically oxaliplatin resistance upregulates soluble vascular endothelial growth factor receptor 1, downregulates vascular endothelial growth factor, and also promotes c-MET, b-ca catenin/transcription factor 4, and AKT activation. We tested whether variation in three serum biomarkers such as the natural c-MET ligand (hepatocyte growth factor), soluble vascular endothelial growth factor receptor 1, and vascular endothelial growth factor-A was associated with efficacy in metastatic colorectal cancer patients treated in the prospective BECOX study. Serum levels of vascular endothelial growth factor-A165, soluble vascular endothelial growth factor receptor 1, and hepatocyte growth factor were assessed by enzyme-linked immunosorbent assay method basally and every 3 cycles (at the time of computed tomography evaluation) in a preplanned translational study in the first-line BECOX trial in metastatic colorectal cancer patients treated with CAPOX plus bevacizumab. Response was evaluated by routine contrast-enhanced computed tomography by RECIST 1.1 by investigator assessment and by three blinded independent radiologists. Ratios between soluble vascular endothelial growth factor receptor 1/vascular endothelial growth factor-A and hepatocyte growth factor/vascular endothelial growth factor-A were established and variations through time were related to RECIST 1.1 by investigator assessment and independent radiologist. The BECOX trial included 68 patients, and 27 patients were analyzed in the translational trial. A total of 80 RECIST 1.1 evaluations were done by investigator assessment and 56 by independent radiologist. We found that a 3.22-fold increase in soluble vascular endothelial growth factor receptor 1/vascular endothelial growth factor-A by investigator assessment and a 3.06-fold increase in soluble vascular endothelial growth factor receptor 1/vascular endothelial growth factor-A by independent radiologist from previous determination were associated with responses compared with 1.38-fold increase by investigator assessment and 1.59 by independent radiologist in non-responders (p= 0.0009 and p = 0.03, respectively). Responders had a 3.36-fold increase in hepatocyte growth factor/vascular endothelial growth factor-A from previous determination by investigator assessment and 3.66-fold increase in hepatocyte growth factor/vascular endothelial growth factor-A by independent radiologist compared with 1.43-fold increase by investigator assessment and 1.53 by independent radiologist for non-responders (p = 0.002 and 0.003, respectively). In conclusion, a decrease in vascular endothelial growth factor-A and an increase in soluble vascular endothelial growth factor receptor 1 during chemotherapy and bevacizumab exposure can contribute to both chemotherapy (due to c- MET/b-catenin activation) and bevacizumab (due to low vascular endothelial growth factor requirements) resistance. Because hepatocyte growth factor levels decrease also during acquired resistance, alternative strategies to hepatocyte growth factor–ligand inhibition should be investigatedThis work was supported by “beca SEOM a Jóvenes Investigadores 2009” and by the Emili Letang fellowship to Estela Pineda

Vascular endothelial growth factor-A mRNA gene expression in clinical phases of multiple sclerosis

Background: Vascular endothelial growth factor A stimulates angiogenesis, but is also pro-inflammatory and plays an important role in the development of neurological disease. This study aimed to investigate whether vascular endothelial growth factor A mRNA expression could be used as a marker for the prediction of susceptibility to multiple sclerosis and relate vascular endothelial growth factor to the clinical phases of multiple sclerosis. Methods: This was a cross-sectional study, consisting of a total of 60 subjects with multiple sclerosis and 20 healthy controls. Subjects were subjected to history taking, neurological examination and peripheral blood sampling for vascular endothelial growth factor A mRNA gene expression. Vascular endothelial growth factor A gene expression was measured by real-time polymerase chain reaction using the SYBR Green technique. Results: Vascular endothelial growth factor A mRNA gene expression level was significantly lower in the multiple sclerosis group than in the healthy control group (P<0.001). Vascular endothelial growth factor A mRNA gene expression level was higher in relapsing remitting multiple sclerosis (RRMS) patients than in those in remission (P<0.001) and in relapsing remitting multiple sclerosis compared with secondary progressive multiple sclerosis (P<0.001). There was no correlation between vascular endothelial growth factor A gene expression levels and duration of disease, multiple sclerosis progression index or expanded disability status scale. Conclusions: A lower vascular endothelial growth factor A mRNA gene expression level was independently associated with a higher risk of multiple sclerosis

Vascular endothelial growth factor-A levels in term neonates

Vascular endothelial growth factor-A (VEGF-A) plays an integral role in physiological and pathophysiological angiogenesis and has increasingly been implicated in the development of retinopathy of prematurity (ROP) in preterm infants. Application of intravitreal anti-VEGF is frequently used to treat ROP with little consideration given to the role of VEGF-A in neonatal growth and development. Previous studies have demonstrated systemic anti-VEGF persistence, reduced peripheral VEGF levels following treatment, and possible diagnostic and prognostic uses for VEGF-A determination. This study seeks to determine a normal range for serum VEGF-A (sVEGF-A) in healthy,term infants. The sVEGF-A levels were obtained from 32 neonates born at term infants (16 males and 16 females) using an enzyme-linked immunosorbent assay. No significant correlations were found between sVEGF-A levels and time of sample collection, birth weight, or gender. The median sVEGF-A level was 976 (394–1635) pg/mL (95% confidence interval for median: 496–1,318 pg/mL). This preliminary study determines a normal range for the sVEGF-A level in healthy, term neonates. This normal range will provide a tool to assist in the diagnosis, prognosis, and monitoring of treatment of infants with ROP

Vascular endothelial growth factor-A (VEGF-A) and chemokine ligand-2 (CCL2) in Amyotrophic Lateral Sclerosis (ALS) patients

Correction to Gupta P K, Prabhakar S, Sharma S, Anand A. Vascular endothelial growth factor-A (VEGF-A) and chemokine ligand-2 (CCL2) in amyotrophic lateral sclerosis (ALS) patients. Journal of Neuroinflammation 8:47

Semaphorin3a disrupts podocyte foot processes causing acute proteinuria

Semaphorin3a was discovered as a secreted guidance protein that acts as a chemorepellent to migrating axons and endothelial cells. In the adult mouse kidney, it is expressed in podocytes and collecting tubules. Here, we show that exogenous semaphorin3a caused acute nephrotic range proteinuria associated with podocyte foot process effacement and fusion, endothelial cell damage, decreased vascular endothelial growth factor-A receptor expression, and downregulation of the slit-diaphragm proteins podocin, nephrin, and CD2-associated protein. When vascular endothelial growth factor 165 was administered at the same time as Semaphorin3a, no proteinuria or renal ultrastructural abnormalities occurred, suggesting that semaphorin3a effects may be mediated, in part, by downregulation of vascular endothelial growth factor receptor 2 signaling. Our findings indicate that a balance of semaphorin3a to vascular endothelial growth factor-A may be important for glomerular filtration barrier homeostasis

The effect of methenamine on vascular development: Experimental investigation using in vivo and insilico methods

Background: Methenamine is a worldwide antibacterial agent for urinary system infections in human and animals. The effect of methenamine consumption during early phase of pregnancy is not fully clarified in previous studies. Vascular development is the essential part of the early embryonic growth. Objective: In this study, we used chicken chorioallantoic membrane to evaluate the effects of methenamine administration on angiogenesis process as a model. Materials and Methods: In this experimental study, 20 Ross 308 eggs (mean weight 55 ± 4) were incubated. The eggs were divided into two equal groups (n = 10/each). In the first group, methenamine (150 mg/kg egg weight) was injected on the shell membrane, and in the second group (control group) phosphate-buffered saline as injected. Methenamine was inoculated at 96 and 120 hr after incubation; 24 hr after the last inoculation, the eggs were removed and the egg’s shell was incised. Then, the development of vascular network and vascular endothelial growth factor A expression was evaluated. Results: Angiogenesis was significantly decreased after methenamine treatment. The indexes such as areas containing vessels, the vessels’ length, the percentage of angiogenesis developing areas, and vascular complexity in the treatment group receiving methenamine were significantly reduced compared to the control group. Vascular endothelial growth factor A expression was suppressed in the methenamine treated group. Conclusion: According to the achieved results, it was defined that methenamine could have an inhibitory effect on the growth and development procedures of extraembryonic vasculature. Key words: Methenamine, Angiogenesis modulating agents, Vascular endothelial growth factor A, Extraembryonic membranes

Simvastatin coating of TiO2 scaffold induces osteogenic differentiation of human adipose tissue-derived mesenchymal stem cells

AbstractBone tissue engineering requires an osteoconductive scaffold, multipotent cells with regenerative capacity and bioactive molecules. In this study we investigated the osteogenic differentiation of human adipose tissue-derived mesenchymal stem cells (hAD-MSCs) on titanium dioxide (TiO2) scaffold coated with alginate hydrogel containing various concentrations of simvastatin (SIM). The mRNA expression of osteoblast-related genes such as collagen type I alpha 1 (COL1A1), alkaline phosphatase (ALPL), osteopontin (SPP1), osteocalcin (BGLAP) and vascular endothelial growth factor A (VEGFA) was enhanced in hAD-MSCs cultured on scaffolds with SIM in comparison to scaffolds without SIM. Furthermore, the secretion of osteoprotegerin (OPG), vascular endothelial growth factor A (VEGFA), osteopontin (OPN) and osteocalcin (OC) to the cell culture medium was higher from hAD-MSCs cultured on scaffolds with SIM compared to scaffolds without SIM. The TiO2 scaffold coated with alginate hydrogel containing SIM promote osteogenic differentiation of hAD-MSCs in vitro, and demonstrate feasibility as scaffold for hAD-MSC based bone tissue engineering