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Peripheral nerves and blood vessels have similar patterns in quail forelimb development. Usually, nerves extend adjacent to existing blood vessels, but in a few cases, vessels follow nerves. Nerves have been proposed to follow vascular smooth muscle, endothelium, or their basal laminae. Focusing on the major axial blood vessels and nerves, we found that when nerves grow into forelimbs at E3.5-E5, vascular smooth muscle was not detectable by smooth muscle actin immunoreactivity. Additionally, transmission electron microscopy at E5.5 confirmed that early blood vessels lacked smooth muscle and showed that the endothelial cell layer lacks a basal lamina, and we did not observe physical contact between peripheral nerves and these endothelial cells. To test more generally whether lack of nerves affected blood vessel patterns, forelimb-level neural tube ablations were performed at E2 to produce aneural limbs; these had completely normal vascular patterns up to at least E10. To test more generally whether vascular perturbation affected nerve patterns, VEGF(165), VEGF(121), Ang-1, and soluble Flt-1/Fc proteins singly and in combination were focally introduced via beads implanted into E4.5 forelimbs. These produced significant alterations to the vascular patterns, which included the formation of neo-vessels and the creation of ectopic avascular spaces at E6, but in both under- and overvascularized forelimbs, the peripheral nerve pattern was normal. The spatial distribution of semaphorin3A protein immunoreactivity was consistent with a negative regulation of neural and/or vascular patterning. Semaphorin3A bead implantations into E4.5 forelimbs caused failure of nerves and blood vessels to form and to deviate away from the bead. Conversely, semaphorin3A antibody bead implantation was associated with a local increase in capillary formation. Furthermore, neural tube electroporation at E2 with a construct for the soluble form of neuropilin-1 caused vascular malformations and hemorrhage as well as altered nerve trajectories and peripheral nerve defasciculation at E5-E6. These results suggest that neurovascular congruency does not arise from interdependence between peripheral nerves and blood vessels, but supports the hypothesis that it arises by a shared patterning mechanism that utilizes semaphorin3A. (C) 2003 Elsevier Science (USA). All fights reserved.

Kidney disease affects over 20 million people in the United States alone. Although the causes of renal failure are diverse, the glomerular filtration barrier is often the target of injury. Dysregulation of VEGF expression within the glomerulus has been demonstrated in a wide range of primary and acquired renal diseases, although the significance of these changes is unknown. In the glomerulus, VEGF-A is highly expressed in podocytes that make up a major portion of the barrier between the blood and urinary spaces. In this paper, we show that glomerular-selective deletion or overexpression of VEGF-A leads to glomerular disease in mice. Podocyte-specific heterozygosity for VEGF-A resulted in renal disease by 2.5 weeks of age, characterized by proteinuria and endotheliosis, the renal lesion seen in preeclampsia. Homozygous deletion of VEGF-A in glomeruli resulted in perinatal lethality. Mutant kidneys failed to develop a filtration barrier due to defects in endothelial cell migration, differentiation, and survival. In contrast, podocyte-specific overexpression of the VEGF-164 isoform led to a striking collapsing glomerulopathy, the lesion seen in HIV-associated nephropathy. Our data demonstrate that tight regulation of VEGF-A signaling is critical for establishment and maintenance of the glomerular filtration barrier and strongly supports a pivotal role for VEGF-A in renal disease.

It has been recognized that there is a group of patients with severe disabling angina and coronary artery disease who are refractory to conventional forms of treatment. Although this issue has already been debated at the level of the National Societies, we felt that it was appropriate to also tackle it at the European level. This is particularly important in view of the rapid pace of growth of this problem and the lack of a standardized approach. This has encouraged the development of a variety of treatments that vary considerably in terms of cost-effectiveness and safety and require proper validation procedures. The aim of this paper is to draw attention to the problem and start a process that will lead to improvement and harmonization of the care of patients with refractory angina.

Our aim was to establish, in patients with solid tumors, the dose-limiting toxicity, maximum tolerated dose (MTD), and pharmacology of PNU-145156E, a new sulfonated distamycin A derivative that blocked circulating angiogenesis-promoting growth factors in animal studies and exhibited an antitumor effect in murine solid tumors. In a Phase I study, PNU-145156E was administered Lv. every 6 weeks. Included were patients with solid tumors; an Eastern Cooperative Oncology Group performance score less than or equal to1; and normal bone marrow, renal, and liver functions and blood clotting tests. Excluded were patients with brain metastases or on steroid medication. Toxicity was scored with the National Cancer Institute Common Toxicity Criteria. Plasma and urine PNU-145156E was measured for pharmacokinetic analysis. The effect of PNU-145156E on serum basic fibroblast growth factor (bFGF) was measured by sandwich ELISA. Twenty-nine patients (median age, 54 years; range, 33-71 years; 19 males and 10 females; median performance score = 1) were treated at dose levels of 100-1050 mg/m(2). We observed, during 47 treatment cycles, erratic but short-lasting decreases of antithrombin III levels (

Background-Hypoxia-inducible factor-1 (HIF-1) is a heterodimeric transcription factor that regulates expression of genes involved in O-2 homeostasis, including vascular endothelial growth factor (VEGF), a potent stimulator of angiogenesis. We sought to exploit this native adaptive response to hypoxia as a treatment for chronic ischemia. Methods and Results-A hybrid protein consisting of DNA-binding and dimerization domains from the HIF-1 alpha subunit and the transactivation domain from herpes simplex virus VP16 protein was constructed to create a strong, constitutive transcriptional activator. After transfection into HeLa, C6, and Hep3B cells, this chimeric transcription factor was shown to activate expression of the endogenous VEGF gene, as well as several other HIF-1 target genes in vitro. The bioactivity of HIF-1 alpha /VP16 hybrid gene transfer in vivo was examined in a rabbit model of hindlimb ischemia. Administration of HIF-1 alpha /VP16 was associated with significant improvements in calf blood pressure ratio, angiographic score, resting and maximal regional blood flow, and capillary density (all P Conclusions-The HIF-1/VP16 hybrid transcription factor is able to promote significant improvement in perfusion of an ischemic limb. These results confirm the feasibility of a novel approach for therapeutic angiogenesis in which neovascularization may be achieved indirectly by use of a transcriptional regulatory strategy.

Based on their location and central role in solid tumor growth, tumor vascular endothelial cells may present an attractive target for the delivery of therapeutic drugs or cells. The potency of blocking the tumor blood supply in eradicating solid tumors was demonstrated recently in a mouse model of tumor vasculature targeting (Huang et al., Science 275: 547-550, 1997). For clinical application of such strategies, tumor endothelium specific target epitopes need to be identified. Recent studies on angiogenesis have identified angiogenesis related molecules as potential target epitopes. Among these are vascular endothelial growth factor (VEGF)/VEGF-receptor complex, alpha v integrins, and Tie receptor tyrosine kinases. Besides blockade of their signalling cascades leading to inhibition of angiogenesis, these epitopes may also be instrumental in tumor vessel specific delivery of therapeutics. Data on the efficacy of therapeutic modalities aimed at these, mostly heterogeneously distributed tumor endothelial epitopes are scarce, and sophisticated experimentation is required to rationalize the development of new therapeutic strategies. Importantly, only detailed evaluations in cancer patients will provide the blueprint for the development of clinically effective tumor vascular targeted therapies. BIOCHEM PHARMACOL 55;12:1939-1945, 1998. (C) 1998 Elsevier Science Inc.

Selective occlusion of tumor vasculature was tested as a therapy for solid tumors in a mouse model. The formation of blood clots (thrombosis) within the tumor vessels was initiated by targeting the cell surface domain of human tissue factor, by means of a bispecific antibody, to an experimentally induced marker on tumor vascular endothelial cells. This truncated form of tissue factor (tTF) had limited ability to initiate thrombosis when free in the circulation, but became an effective and selective thrombogen when targeted to tumor endothelial cells. Intravenous administration of the antibody-tTF complex to mice with large neuroblastomas resulted in complete tumor regressions in 38 percent of the mice.

Pediatric sarcomas, including rhabdomyosarcomas, Ewing's sarcoma, and osteosarcoma, are aggressive tumors with poor survival rates. To overcome problems associated with nonselectivity of the current therapeutic approaches, targeted therapeutics have been developed. Currently, an increasing number of such drugs are used for treating malignancies of adult patients but little is known about their effects in pediatric patients. We analyzed expression of 24 clinically approved target genes in a wide variety of pediatric normal and malignant tissues using a novel high-throughput systems biology approach. Analysis of the Genesapiens database of human transcriptomes demonstrated statistically significant up-regulation of VEGFC and EPHA2 in Ewing's sarcoma, and ERBB3 in alveolar rhabdomyosarcomas. In silico data for ERBB3 was validated by demonstrating ErbB3 protein expression in pediatric rhabdomyosarcoma in vitro and in vivo. ERBB3 overexpression promoted whereas ERBB3-targeted siRNA suppressed rhabdomyosarcoma cell gowth, indicating a functional role for ErbB3 signaling in rhabdomyosarcoma. These data suggest that drugs targeting ErbB3, EphA2 or VEGF-C could be further tested as therapeutic targets for pediatric sarcomas.

Purpose To evaluate quantitatively the apoptotic activity after intravitreal injections of pegaptanib sodium and bevacizumab in the rabbit retina. Methods Different doses of bevacizumab (0.25, 0.625, 1.25, and 2.5 mg) and pegaptanib sodium (0.15, 0.3, and 0.6 mg) were injected intravitreally in 48 rabbits. The eyes were enucleated at different times for early studies at day 14 and for late studies at 3 months after a single injection or at 3 months, with 1 injection in each of the 3 months (day 90). The time course and dose-response of photoreceptor cells in the rabbit retina after intravitreal injection of bevacizumab or pegaptanib sodium were examined by histologic analysis with hematoxylin and eosin (H&E) staining, caspase-3 and -9 immunostaining, and in situ terminal-deoxynucleotidyl transferase-mediated biotin-deoxyuridine triphosphate nick-end labeling (TUNEL) of DNA fragments of paraffin-embedded sections. Results No sign of retinal toxicity was seen in H&E stained histologic sections of eyes that had received bevacizumab or pegaptanib sodium. Nuclear DNA fragmentation in the outer retinal layers shown by the TUNEL method was evident in the high-dose groups (55.3% with 1.25 mg and 64.5% with 2.5 mg bevacizumab, and 48.5% with 0.6 mg pegaptanib sodium) at 14 days and also in the clinical dose groups (49.8% with three injections [1 each month] of 0.625 mg bevacizumab and 44.3% with 0.15 mg pegaptanib sodium) at 90 days. The ratios of TUNEL-positive cells in physiologic saline and the sham-control groups were 32.3% and 21%, respectively. Conclusions Intravitreal injection of bevacizumab and pegaptanib sodium caused a significant increase in apoptotic activity in rabbit photoreceptor cells. However, although bevacizumab caused increasing apoptotic activity at higher doses, similar dose-dependent adverse effects were not evident for pegaptanib sodium.

Here we describe a triple transgenic mouse system, which combines the tissue specificity of any Cre-transgenic line with the inducibility of the reverse tetracycline transactivator (rtTA)/tetracycline-responsive element (tet-O)-driven transgenes. To ensure reliable rtTA expression in a broad range of cell types, we have targeted the rtTA transgene into the ROSA26 locus. The rtTA expression, however, is conditional to a Cre recombinase-mediated excision of a STOP region from the ROSA26 locus. We demonstrate the utility of this technology through the inducible expression of the vascular endothelial growth factor (VEGF-A) during embryonic development and postnatally in adult mice. Our results of adult induction recapitulate several different hepatic and immune cell pathological phenotypes associated with increased systemic VEGF-A protein levels. This system will be useful for studying genes in which temporal control of expression is necessary for the discovery of the full spectrum of functions. The presented approach abrogates the need to generate tissue-specific rtTA transgenes for tissues where well-characterized Cre lines already exist.

Potent sequence selective gene inhibition by siRNA 'targeted' therapeutics promises the ultimate level of specificity, but siRNA therapeutics is hindered by poor intracellular uptake, limited blood stability and non-specific immune stimulation. To address these problems, ligand-targeted, sterically stabilized nanoparticles have been adapted for siRNA. Self-assembling nanoparticles with siRNA were constructed with polyethyleneimine (PEI) that is PEGylated with an Arg-Gly-Asp (RGD) peptide ligand attached at the distal end of the polyethylene glycol (PEG), as a means to target tumor neovasculature expressing integrins and used to deliver siRNA inhibiting vascular endothelial growth factor receptor-2 (VEGF R2) expression and thereby tumor angiogenesis. Cell delivery and activity of PEGylated PEI was found to be siRNA sequence specific and depend on the presence of peptide ligand and could be competed by free peptide. Intravenous administration into tumor-bearing mice gave selective tumor uptake, siRNA sequence-specific inhibition of protein expression within the tumor and inhibition of both tumor angiogenesis and growth rate. The results suggest achievement of two levels of targeting: tumor tissue selective delivery via the nanoparticle ligand and gene pathway selectivity via the siRNA oligonucleotide. This opens the door for better targeted therapeutics with both tissue and gene selectivity, also to improve targeted therapies with less than ideal therapeutic targets.

Fibrosis represents the end-stage of a broad range of disorders affecting organ function. These disorders are often associated with aberrant angiogenesis, but whether vascular abnormalities during fibrosis are characterized by excessive or diminished neo-vascularization remains questionable. Strikingly, activation of the coagulation cascade is frequently observed in association with the progression of fibroproliferative disorders. As we recently showed that coagulation factor (F)Xa induced fibrotic responses in fibroblasts, we hypothesized that FXa might indirectly induce angiogenesis by triggering fibroblasts to secrete proangiogenic factors. In the present study, we show that although FXa induces p42/44 MAP Kinase phosphorylation in endothelial cells, it has no direct effect on endothelial cell proliferation, protein synthesis and tube formation. In contrast, conditioned medium of fibroblasts stimulated with FXa enhanced endothelial cell proliferation, extra cellular matrix synthesis, wound healing and endothelial tube formation. FXa induced VEGF production by fibroblasts and a VEGF neutralizing antibody blocked the indirect effect of FXa on proliferation and realignment of endothelial cells identifying VEGF as a crucial player in angiogenesis during coagulation factor-induced fibrosis. Overall, our results establish a link between the coagulation cascade and angiogenesis during fibrosis. (C) 2009 Elsevier B.V. All rights reserved.

Angiogenesis, the process of blood vessel formation, is necessary for tissue survival in normal and pathologic conditions. Increased angiogenesis in BM niche is correlated with leukemia progression and resistance to treatment. Angiogenesis can interfere with disease progression and several angiogenic (such as vascular growth factors) as well as anti-angiogenic factors (i.e. angiostatin) can affect angiogenesis. Furthermore, miRs can affect the angiogenic process by inhibiting angiogenesis or increasing the expression of growth factors. Given the importance of angiogenesis in BM for maintenance of leukemic clones, recognition of angiogenic and anti-angiogenic factors and miRs as well as drug resistance mechanisms of leukemic blasts can improve the therapeutic strategies. We highlight the changes in angiogenic balance within the BM niche in different leukemia types. Moreover, we explored the pathways leading to drug resistance in relation to angiogenesis and attempted to assign interesting candidates for future research.

From developmental stages until adulthood, the circulatory system remodels in response to changes in blood flow in order to maintain vascular homeostasis. Remodeling processes can be driven by de novo formation of vessels or angiogenesis, and by the restructuration of already existing vessels, such as vessel enlargement and regression. Notably, vessel enlargement can occur as fast as in few hours in response to changes in flow and pressure. The high plasticity and responsiveness of blood vessels rely on endothelial cells. Changes within the bloodstream, such as increasing shear stress in a narrowing vessel or lowering blood flow in redundant vessels, are sensed by endothelial cells and activate downstream signaling cascades, promoting behavioral changes in the involved cells. This way, endothelial cells can reorganize themselves to restore normal circulation levels within the vessel. However, the dysregulation of such processes can entail severe pathological circumstances with disturbances affecting diverse organs, such as human hereditary telangiectasias. There are different pathways through which endothelial cells react to promote vessel enlargement and mechanisms may differ depending on whether remodeling occurs in the adult or in developmental models. Understanding the molecular mechanisms involved in the fast-adapting processes governing vessel enlargement can open the door to a new set of therapeutical approaches to be applied in occlusive vascular diseases. Therefore, we have outlined here the latest advances in the study of vessel enlargement in physiology and pathology, with a special insight in the pathways involved in its regulation. ispartof: Frontiers In Physiology vol:12 ispartof: location:Switzerland status: published

Purpose: Vascular endothelial growth factor (VEGF) is a potent angiogenic agent and plays a major role in tumor growth and metastases. We have previously reported the locoregional (i.p.) delivery of adenovirus-mediated antiangiogenic soluble FLT-1 (sFLT-1; a naturally encoded potent VEGF antagonist) gene therapy to inhibit VEGF action in a murine ovarian carcinoma model. This study was predicated on the fact that systemic delivery of sFLT-1 might allow an approach for therapy of disseminated tumor. The purpose of this study is to test the effects of i.v. delivered, adenovirus-mediated sFLT-1 on the survival duration in a murine ovarian tumor model and to evaluate the safety of i.v.-delivered versus i.p.-delivered adenovirus-mediated sFLT-1 in non-tumor-bearing mice. Experimental Design: To determine the effects of i.v.administered adenovirus-mediated sFLT-1 on survival duration of mice bearing i.p. human ovarian tumors, an E1A/B-deleted, (replication-deficient) infectivity-enhanced recombinant adenovirus AdRGDGFPsFLT-1 encoding cDNA for both sFLT-1 and GFP (green fluorescent protein), a control adenovirus AdRGDGFP encoding GFP alone, or PBS was delivered i.v. The therapeutic effect of sFLT-1 was evaluated by survival duration of the mice. Furthermore, the safety of i.v.- or i.p.-delivered adenovirus-mediated sFLT-1 was evaluated by administering AdRGDGFPsFLT-1, AdRGDGFP, or PBS either i.v. or i.p. into non-tumor-bearing mice. Adenovirus-mediated gene expression was determined by determining GFP expression using fluorescent microscopy and by assessing sFLT-1 expression in liver, lungs, spleen, and kidneys by immunohistochemistry using anti-FLT-1 monoclonal antibody. Systemic levels of sFLT-1 were evaluated by ELISA and the toxicity was evaluated by histopathology. Results: The i.v. delivery of AdRGDGFPsFLT-1 in the ovarian tumor model resulted in a shorter duration of survival of the mice as compared with the control group. Furthermore, in the safety evaluation experiment, i.v. administration of AdRGDGFPsFLT-1 in non-tumor-bearing mice principally localized to the liver. This localization lead to sFLT-1 overexpression, mainly in the liver, resulting in hemorrhage and tissue toxicity. However, i.p. delivery of AdRGDGFPsFLT-1 did not localize principally to the liver, leading to negligible expression of sFLT-1, and no intrahepatic hemorrhage or toxicity was observed. The i.v. delivery of the control virus AdRGDGFP also principally localized to the liver, leading to GFP expression mainly in the liver. However, neither hemorrhage nor morphological cytotoxicity was observed. i.p. delivery of AdRGDGFP resulted in ectopic localization to the liver with very little GFP expression and no toxicity. These results suggest that overexpression of sFLT-1 in the liver as a result of i.v. delivery is hepatotoxic. Conclusions: Our results suggest that i.v. delivery of the sFLT-1 gene via replication-deficient, infectivity-enhanced recombinant adenoviral vectors will result in overexpression of sFLT-1 in the liver leading to unacceptable hepatotoxicity. Tumor-specific targeting of the vectors and tumor-specific expression strategies should be used to ensure a clinically useful antiangiogenesis gene therapy.

The purpose of this study is to examine the usefulness of histogram analysis combined with vessel size index (VSI) magnetic resonance imaging for the specific characterization of brain tumor microvasculature in a panel of six volume-matched glioma xenografts. Using a simple descriptive histogram analysis, significant differences of the mean tumoral VSI (P = 0.0035 for 9L, P = 0.008 for glioma mix, P = 0.05 for C6), the 75th VSI percentile (P = 0.003-0.075) as well as the 25th and median blood volume (BV) percentiles were found in murine gliomas compared to their contralateral healthy brain. Using a segmented histogram analysis, dilatation of already existing vessels in murine gliomas and development of new small caliber vessels in human glioblastomas were suggested. Most gliomas showed a higher proportion of pixels with BV below 1% (glioma mix [21% vs 1%], Glioblastoma 2 (GBM2) [9% vs 3.7%]) and a smaller proportion of pixels with BV in the range 1.7-6.3% (65 vs 90% for glioma mix, 80 vs 85% in GBM2) relative to their contralateral part. In glioblastomas, VSI and BV distributions were similar to normal brain distributions and in agreement with immunohistochemical findings. The histogram analysis of VSI and BV heterogeneity in experimental brain tumors allowed detection of microregional differences in gliomas from different origins. Magn Reson Med 65:778-789, 2011. (c) 2010 Wiley-Liss, Inc.

This study was supported by Scientific Research Projects Unit of Pamukkale University (PAU-BAP2019BSP008). OBJECTIVE Defects in apoptotic cell death which restrict the success of conventional cytotoxic therapies have pivotal roles in a number of pathological conditions including cancer. However, a novel drug class targeting pro-survival Bcl-2 protein family members has been developed with the understanding of the structures and interactions of Bcl-2 proteins. Within this new class, Bcl-2/Bcl-xL inhibitor Navitoclax and Bcl-2 specific inhibitor Venetoclax have been shown to demonstrate strong anticancer activities on several types of cancers. But their low affinity to other anti-apoptotic proteins limits their clinical usage. Here, we investigated the cytotoxic and apoptotic effects of Navitoclax/Venetoclax and their combinations with specific tyrosine kinase inhibitor Apatinib on estrogen receptor (ER)-positive MCF-7 and ER-negative MDA-MB-231 breast cancer cell lines. METHODS MTT assay was used for the evaluation of the inhibition of cancer cell proliferation. ELISA test and Quantitative real-time PCR assay was performed to determine the role of caspase-3, Bak, Bax, Bcl-2, Bcl-xL and Mcl-1 proteins in the inhibition of cell proliferation triggered by the tested agents. RESULTS We found that aggressive MDA-MB-231 cell line was more sensitive to all tested agents. Apatinib significantly enhanced Navitoclax/Venetoclax mediated inhibition of cell viability in both cancer cell lines despite up-regulation in the expression levels of Bcl-2 and Mcl-1 genes. We further demonstrated significant Bak/Bax and caspase-3 expression in less aggressive MCF-7 cells. CONCLUSION Our findings have impacts on Navitoclax/Venetoclax plus Apatinib based therapy for breast adenocarcinoma. On the other hand, further studies should be conducted to elucidate the mechanisms underlying synergistic effects of Navitoclax/Venetoclax plus Apatinib combinations. Pamukkale University PAU-BAP2019BSP008

Rats injected in the hind paw with a mixture of Mycobacterium butirricum emulsified in mineral oil (FA) developed a severe polyarthritis that shared some immunological features with human rheumatoid arthritis. After this local administration, rats developed a secondary lesion (edema) in the contralateral paw, which is a hallmark of immune system activation. In vivo intravenous treatment with a monoclonal anti-very late antigen (VLA)-1 antibody (HA31/8) significantly reduced the edema formation in the contralateral paw. T cells isolated from contralateral paw draining lymph nodes of FA rats treated with HA31/8 showed a reduced cell proliferation in vitro, after stimulation with concanavalin A. Furthermore FACS analysis showed that the reduction in proliferation was concomitant to a reduction in the number of T cells positive to surface IL-2 receptor expression. Our data indicate that after in vivo treatment with a monoclonal anti-very late antigen-1 antibody, there is a beneficial effect on the development of the secondary lesion, which correlates to the reduced ability of T cells to proliferate in vitro as well as to a reduced surface expression of IL-2 receptor. The association of this antibody to other drugs interfering at other levels in rheumatoid arthritis may open a new therapeutic window.

AIM: To investigate the efficacy of sunitinib in patients with advanced melanoma and to correlate angiogenic biomarkers with response and survival. PATIENTS AND METHODS: We performed a phase II study in patients with advanced pre-treated melanoma. The primary endpoint was tumor response. Blood samples for biomarker analysis including vascular endothelial growth factor (VEGF), and its receptors VEGFR1 and -2, placental growth factor (PlGF) and circulating endothelial cells (CEC) were collected at baseline and during the first cycle. RESULTS: Four out of 39 patients (13%) achieved a partial response and eight (26%) stable disease. Time to progression was at least six months in seven patients. High baseline VEGFR1 levels and high baseline PlGF levels were both associated with a non-significant worse survival (p=0.08 for both). CONCLUSION: Sunitinib demonstrates limited activity in unselected patients with refractory advanced melanoma, but a minority of patients experienced long-term disease control. Identification of these patients remains a challenge.

A major challenge for therapeutic delivery of angiogenic agents such as vascular endothelial growth factor (VEGF) is to achieve sustained, low dose signaling leading to durable neovessel formation. To this end, we recently created a variant of VEGF(121), TG-VEGF(121) that directly binds to fibrin and gets released locally in proteolysis-triggered manner. Here we combined noninvasive biophotonic monitoring of VEGF receptor 2 gene activation in transgenic VEGFR2-luc mice and histomorphometry to compare endothelial activation and long-term neovascularization by actively released TG-VEGF(121) versus passively released, diffusible wild-type VEGF(121) in subcutaneous fibrin implants. Monitoring in real-time over 3 weeks of luciferase signal driven by the VEGFR2 promoter revealed endothelial activation in skin exposed to wild-type VEGF(121), but no detectable elevation over fibrin alone by TG-VEGF(121). Histology at 3 weeks, however, demonstrated that TG-VEGF(121) promoted vessel growth significantly more effectively and reliably than wild-type VEGF(121). The majority of vessels surviving to 3 weeks contained stabilizing smooth muscle cells. Yet, by 6 weeks, no extra vessels induced by exogenous VEGF were left. In conclusion, release of fibrin-conjugated variant TG-NEGF(121) elicited lower VEGFR2-luc activation than wild-type VEGF(121) yet significantly more vascularization. In the absence of true physiological demand, even stabilized vessels are ultimately regressed. (c) 2007 Elsevier Ltd. All rights reserved.

Macrophages sustain tumour progression by facilitating angiogenesis, promoting immunosuppression, and enhancing cancer cell invasion and metastasis. They also modulate tumour response to anti-cancer therapy in pre-clinical models. This knowledge has motivated the development of agents that target tumour-associated macrophages (TAMs), some of which have been investigated in early clinical trials. Here, we provide a comprehensive overview of the biology and therapeutic targeting of TAMs, highlighting opportunities, setbacks, and new challenges that have emerged after a decade of intense translational and clinical research into these multifaceted immune cells. (c) 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Purpose: To report multimodal imaging findings including optical coherence tomography angiography (OCT-A) of a patient presenting with a quiescent choroidal neovascularization (CNV) in one eye and an active CNV in the fellow eye, complicating retinitis pigmentosa (RP) linked to PRPH2 pathogenic variant, with follow-up and management of both eyes. Methods: Observational case report. Results: A 40-year-old female with history of autosomal dominant RP consulted for acute visual loss in her right eye (RE). Multimodal imaging including OCT-A confirmed the diagnosis of active type 2 CNV in the RE and highlighted an incidental asymptomatic non-exudative "quiescent" CNV in the left eye (LE). This complication was managed by intra-vitreal Bevacizumab injections in the RE and regular monitoring of the LE. Frequent follow-up could detect early CNV activation signs in LE allowing early treatment. Mutation analysis of PRPH2 exons identified a known heterozygous pathogenic missense variation c.646C>T, p.P216S in exon 2. Conclusion: Multimodal imaging and especially OCT-A can be of a great help in the diagnosis and the management of CNV complicating RP, even at the stage of quiescent CNV. In presence of neovascular complication, PRPH2 gene should be investigated because of its frequent macular involvement despite high phenotypic variability.

Aim To investigate the feasibility of using bevacizumab to improve the survival of American Joint Committee on Cancer (AJCC) stage III melanoma patients, we investigated how a single bevacizumab treatment affected nodal disease and a panel of biomarkers in clinically fluorodeoxyglucose positron emission tomography (FDG-PET)/computed tomography (CT)-staged, stage III melanoma patients, prior to therapeutic lymph node dissection (TLND). Methods Four weeks before TLND, nine patients (median age 50, range 28.8–62.1 years; two male, seven female) with palpable lymph node metastases received 7.5 mg/kg bevacizumab. Before and after this treatment, all patients were assessed by measurements of the maximum standardized uptake value (SUVmax) by FDG-PET scan, and serum S-100B and lactate dehydrogenase (LDH). After TLND, the dissection specimen was analyzed for number of removed lymph nodes, number of metastatic lymph nodes, and tumor necrosis. Results Median follow-up was 15.5 (2.2–32.9) months. Histopathological analysis revealed tumor necrosis in six patients, of whom five had an S-100B decline and one had an unchanged S-100B level after bevacizumab. The other three patients showed an S-100B increase and no necrosis. Tumor necrosis was correlated with S-100B decrease (P = 0.048). No association was found between necrosis and the markers SUVmax and LDH. No wound healing disturbances were encountered. Conclusion Tumor necrosis in dissection specimens was associated with declining S-100B levels, while elevated S-100B was only found in cases with no necrosis. Bevacizumab might be useful in treating AJCC stage III melanoma patients prior to TLND, and S100-B appears to be a useful marker for assessment of treatment effects.

Aims and Background Matrix metalloproteinase (MMP) family member MMP-9 degrades type IV collagen, which is one of the main constituents of the basement membrane. MMP-9 is closely associated with the invasive and metastatic potential of most types of lung cancer. In this study we investigated the levels of MMP-9 in serum and bronchial lavage fluid from lung cancer patients and compared them with the levels in patients with nonmalignant lung disease. We also attempted to clarify the possible relationship between serum and bronchial lavage fluid MMP-9 levels and histopathology, staging and metastasis of lung cancer. Study Design The study group consisted of 34 patients with lung cancer. The control group comprised 21 patients with nonmalignant lung disease. MMP-9 levels in serum and bronchial lavage fluid were evaluated by ELISA. Results MMP-9 levels in serum samples from the group with malignant disease were significantly higher than those from the control group (P 0.05). Serum MMP-9 levels were two-fold higher than those in bronchial lavage, but there was no correlation between bronchial lavage and serum levels in both groups (r = 0.18, P >0.05). In the group with malignant disease, MMP-9 levels in serum and bronchial lavage fluid did not show any relationship with histopathological type and tumor stage. There was a statistically significant correlation between serum MMP-9 levels and local tumor stage in smoking nonsmall cell lung cancer (NSCLC) patients (r = 0.33, P Conclusion From our data it can be concluded that MMP-9 levels of serum but not of bronchial lavage fluid can be helpful in differentiating between malignant and benign lung diseases, and are related to the local stage in NSCLC patients and general clinical status of lung cancer patients.

Summary Hematopoietic stem and progenitor cell (HSPC) engraftment after transplantation during anticancer treatment depends on support from the recipient bone marrow (BM) microenvironment. Here, by studying physiological homing of fetal HSPCs, we show the critical requirement of balanced local crosstalk within the skeletal niche for successful HSPC settlement in BM. Transgene-induced overproduction of vascular endothelial growth factor (VEGF) by osteoprogenitor cells elicits stromal and endothelial hyperactivation, profoundly impacting the stromal-vessel interface and vascular architecture. Concomitantly, HSPC homing and survival are drastically impaired. Transcriptome profiling, flow cytometry, and high-resolution imaging indicate alterations in perivascular and endothelial cell characteristics, vascular function and cellular metabolism, associated with increased oxidative stress within the VEGF-enriched BM environment. Thus, developmental HSPC homing to bone is controlled by local stromal-vascular integrity and the oxidative-metabolic status of the recipient milieu. Interestingly, irradiation of adult mice also induces stromal VEGF expression and similar osteo-angiogenic niche changes, underscoring that our findings may contribute targets for improving stem cell therapies., Graphical abstract, Highlights • Establishment of BM hematopoiesis is coupled to development of the skeletal niches • Primary HSPC seeding of bone depends on balanced molecular crosstalk in the niche • Stromal VEGF triggers EC activation and controls stromal-vascular niche integrity • Excessive skeletal VEGF deranges cell metabolism and induces oxidative stress in BM, Mesnieres et al. show that increased VEGF in fetal bone disrupts stromal-vascular integrity, alters cell metabolism, and induces oxidative stress in the developing bone marrow niche, blocking the homing of endogenous hematopoietic stem/progenitor cells. Post-natal irradiation, a common stem cell transplantation pretreatment, induces similar niche alterations, thus opening therapeutic strategies.

BackgroundBv8, prokineticin-1, or endocrine gland-vascular endothelial growth factor, and prokineticin-2 are recently isolated peptide agonists of two G protein-coupled receptors, prokineticin receptor-1 (PROKR 1) and PROKR 2, and have been described as affecting a number of myeloid cell functions. We evaluated the impact of Bv8 on lymphoid cells by investigating its ability to modulate T cell cytokine balance in mouse.ResultsThe production of T-helper1 cytokines (IL-2, IFN-γ and IL-1β), the T-helper 2 cytokine IL-4, and the anti-inflammatory cytokine IL-10 by mouse splenocytes was evaluated after polyclonal stimulation or immunisation with the keyhole limpet hemocyanin protein antigen by measuring cytokine levels. When addedin vitroto Con-A-stimulated splenocytes, Bv8 significantly increased IL-1β and decreased IL-4 and IL-10; IL-2 and IFN-γ were not affected. Similar results were obtained when Bv8 was administeredin vivo. In KLH-immunised mice, splenocytes restimulatedin vitrowith KLH and Bv8 produced significantly smaller amounts of IL-4 and IL-10. KLH-induced IL-10 and IL-4 production was also significantly blunted in animals administered Bv8in vivoat the time of KLH immunisation or two weeks later. The Bv8-induced effects were lost in mice lacking the PROKR 1 gene, thus indicating that PROKR 1 is the receptor involved in the modulation of cytokines.ConclusionThese findings indicate that Bv8/prokineticin-1 is a novel modulator of lymphoid functions, and may be a suitable target for new immunopharmacological strategies.