Higher Levels Of VEGF Research Articles

Proliferative activity of liver growth factor is associated with an improvement of cigarette smoke-induced emphysema in mice.

Cigarette smoke (CS)-induced emphysema is a major component of chronic obstructive pulmonary disease (COPD). COPD treatment is based on the administration of bronchodilators and corticosteroids to control symptoms and exacerbations, however, to date, there are no effective therapies to reverse disease progression. Liver growth factor (LGF) is an albumin-bilirubin complex with mitogenic properties, whose therapeutic effects have previously been reported in a model of emphysema and several rodent models of human disease. To approach the therapeutic effect of LGF in a model of previously established emphysema, morphometric and lung function parameters, matrix metalloproteinase (MMP) activity and the expression of several markers, such as VEGF, PCNA, 3NT and Nrf2, were assessed in air-exposed and CS-exposed C57BL/6J male mice with and without intraperitoneal (i.p.) injection of LGF. CS-exposed mice presented a significant enlargement of alveolar spaces, higher alveolar internal area and loss of lung function that correlated with higher MMP activity, higher expression of 3NT and lower expression of VEGF. CS-exposed mice injected with LGF, showed an amelioration of emphysema and improved lung function, which correlated with lower MMP activity and 3NT expression and higher levels of VEGF, PCNA and Nrf2. Taken together, this study suggests that LGF administration ameliorates CS-induced emphysema, highlights the ability of LGF to promote alveolar cell proliferation and may be a promising strategy to revert COPD progression.

GAPDH enhances the aggressiveness and the vascularization of non-Hodgkin's B lymphomas via NF-κB-dependent induction of HIF-1α.

Deregulated expression of glycolytic enzymes contributes not only to the increased energy demands of transformed cells but also has non-glycolytic roles in tumors. However, the contribution of these non-glycolytic functions in tumor progression remains poorly defined. Here, we show that elevated expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), but not of other glycolytic enzymes tested, increased aggressiveness and vascularization of non-Hodgkin's lymphoma. Elevated GAPDH expression was found to promote nuclear factor-κB (NF-κB) activation via binding to tumor necrosis factor receptor-associated factor-2 (TRAF2), enhancing the transcription and the activity of hypoxia-inducing factor-1α (HIF-1α). Consistent with this, inactive mutants of GAPDH failed to bind TRAF2, enhance HIF-1 activity or promote lymphomagenesis. Furthermore, elevated expression of gapdh mRNA in biopsies from diffuse large B-cell non-Hodgkin's lymphoma patients correlated with high levels of hif-1α, vegf-a, nfkbia mRNA and CD31 staining. Collectively, these data indicate that deregulated GAPDH expression promotes NF-κB-dependent induction of HIF-1α and has a key role in lymphoma vascularization and aggressiveness.

AI-10 * DISTINCT EGFR SIGNALING IN GLIOBLASTOMA: WILD-TYPE EGFR PROMOTES INVASION WHILE EGFRvIII DRIVES PROTOTYPICAL SFK c-SRC ACTIVATION TO FOSTER ANGIOGENESIS

EGFR gene amplification is observed in upwards of 40% of glioblastoma (GBM) biopsies, and genetic aberration to EGFR at large has been described to occur in excess of 50%. Our lab has developed a clinically relevant in vivo xenograft model derived from patient biopsies in which we are able to accurately study EGFR signaling in human GBM. We previously reported that wild-type EGFR amplification and activation promotes invasion and development of GBM independent of angiogenesis. Importantly, detected in half of GBMs harboring EGFR amplification, the most prominent EGFR mutation arises upon deletion of exons 2 through 7 to generate the constitutively active truncation mutant EGFRvIII. Here we report that while wild-type EGFR overexpression sustains invasion, EGFRvIII, in contrast, induces more aggressive and angiogenic tumor growth. We further performed signaling complex immunocapture mass spectrometry which revealed that EGFRvIII-mediated signaling is divergent from that of its wild-type counterpart. In particular the non-receptor tyrosine kinase c-SRC was highly upregulated and activated in EGFRvIII tumors as verified on western blots and by immunohistochemistry. Inhibition of c-SRC activity by shRNA and Src inhibitors decreased VEGF levels in EGFRvIII tumor cells. Furthermore, EGFRvIII+ xenograft tumors expressing c-SRC shRNA became less angiogenic and aggressive - indeed similar to control tumors lacking EGFRvIII. When overexpressing constitutively activated Src in control tumor cells, we could recapitulate the oncogenic phenotype of EGFRvIII as the tumor cells secreted higher levels of VEGF and became more aggressive and angiogenic in vivo. We hereby report evidence that the EGFRvIII-driven oncogenic activity and angiogenic tumor growth is mediated by c-SRC. In conclusion, our results suggest that the EGFRvIII-SRC-VEGF axis represents an important mechanism of tumor angiogenesis in GBM.

Expression of Lymphangiogenic Markers in Rejected Human Corneal Buttons after Penetrating Keratoplasty

Purpose: To investigate the extent and distribution of lymphangiogenesis in the rejected corneal graft, we determined the expression of several lymphangiogenic markers in rejected human corneal buttons. Material and methods: Thirty-four corneal buttons were obtained from patients who underwent re-keratoplasty for graft rejection after penetrating keratoplasty. All corneas showed signs of rejection, such as, sudden mutton-fat keratic precipitates (KPs) or lines before re-keratoplasty. The corneas were halved, and one half was used for immunostaining and the other half was used for RT-PCR. Expression of vascular endothelial growth factor (VEGF)-A, VEGF-C, VEGF-D, VEGFR-2, VEGFR-3, LYVE-1 and podoplanin were measured as lymphangiogenic markers. Four non-operated normal corneas were used as controls. Results: Numerous podoplanin positive cells were found in the anterior and posterior stroma. However, LYVE-1 positive mature lymphatics were found only in herpetic keratitis (HK)-induced graft rejection, and not in pseudophakic bullous keratopathy (PBK). RT-PCR showed that levels of VEGF-A, VEGF-C, VEGFR-2, and VEGFR-3 mRNAs were elevated in rejected corneal buttons versus the non-operated control corneas. Based upon the pre-keratoplasty pathologic conditions, HK cases showed higher levels of VEGF-A and VEGFR-2 than PBK. The mRNA ratios (keratoplastic cornea/normal cornea) for VEGF-A and VEGFR-2 were 8.9 and 5.8, respectively. Conclusions: The results suggested that the VEGF-A and the VEGFR-2 may be a more important pathway for lymphangiogenesis in rejected corneal grafts than the VEGFR-3. In addition, organized lymphangiogenesis is more prominent in HK than PBK.

The involvement of high mobility group 1 cytokine and phospholipases A2 in diabetic retinopathy

BackgroundDiabetic retinopathy, the main microvascular complications of diabetes and one of the leading causes of blindness worldwide. Interesting reports on the role of inflammatory/proangiogenic high mobility group 1 (HMGB-1) cytokine and phospholipases A2 (PLA2) in neovascularization have diverted our concentration to reveal whether HMGB-1 and PLA2 plays role in diabetic retinopathy.MethodsWe performed our study in streptozotocin (STZ)-induced diabetic rat model. The expression levels of the cytokines, chemokines, and cell adhesion molecules in retinal tissues were evaluated by quantitative RT-PCR. HMGB-1 and PLA2 protein levels along with VEGF, TNF-α, IL-1β and ICAM-1 levels were also measured.ResultsWe observed the retinal pericytes, endothelial injury/death and breakdown of blood–retinal barrier (BRB). The protein expression of HMGB-1, PLA2 and IL-1β were significantly increased in micro vessels from retina of diabetic rats. Diabetic rats had also high retinal levels of VEGF, ICAM-1 and TNF-α. Further investigation revealed that pericyte death is mediated by HMGB-1-induced cytotoxic activity of glial cells, while HMGB-1 can directly mediate endothelial cell death. Similarly, increased expression of PLA2 represents the diabetic mediated alteration of BRB, perhaps up regulating the VEGF.ConclusionsOur data suggest that HMGB-1 and PLA2 involved in retinal pericyte and endothelial injury and cell death in diabetic retinopathy. From this study, we suggest that HMGB-1 and PLA2 may be interesting targets in managing diabetic retinopathy.

Abstract 4097: Vacuolar ATPase subunit a2 is associated with immunosuppression in cancer

Abstract Macrophage polarization contributes to distinct human pathologies. In tumors, a polarized M2 phenotype called tumor-associated macrophages (TAMs), are associated with promotion of invasion and angiogenesis. In cancer cells, vacuolar ATPase (V-ATPase), a multi-subunit enzyme, is expressed on the plasma/vesicular membranes and critically influences the metastatic behavior. In addition, the soluble, cleaved N-terminal domain of a2 isoform of V-ATPase (a2NTD) is associated with in vitro induction of pro-tumorigenic properties in monocytes. Monocytes induced with recombinant a2NTD showed polarization towards M2 macrophage subtype by expressing high levels of mannose receptor-1, Arginase-1, IL-10, MMP-9, VEGF and TGF-β. Additionally, co-culture of these macrophages enhances invasion and angiogenesis of tumor cells and suppression of T cell activation. This activity of the a2 isoform of V-ATPase (a2V) caused us to further investigate its role in cancer progression by evaluating the effects of a2V knock down on tumor cells. In this study, we have successfully deleted a2V gene in mouse 4T1 breast cancer cells using shRNA mediated knock down. These knock down cell lines are co-cultured with macrophages to evaluate previously observed immuno-modulatory effect of a2NTD. In addition, a2V knock down cells are injected into the Balb/c mice to generate tumors. The effect of a2V gene deletion on tumor progression and immune responses are evaluated in mice. We show that in the absence of a2V (finally a2NTD) growth and progression of tumor are suppressed by dominated host immune responses. Citation Format: Gajendra K. Katara, Arpita Kulshrestha, Mukesh Jaiswal, Alice Gilman-Sachs, Kenneth D. Beaman. Vacuolar ATPase subunit a2 is associated with immunosuppression in cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4097. doi:10.1158/1538-7445.AM2014-4097

A Randomized Phase Ii Study of Paclitaxel-Carboplatin-Bevacizumab (Pcb) with or Without Nitroglycerin Patches (Ntg) in Patients (Pts) with Stage Iv Non-Squamous-Non-Small Cell Lung Cancer (Ns-Nsclc)(Nvalt 12), Impact of Circulating Vascular Endothelial Growth Factor (Vegf) Levels

ABSTRACT Aim: NTG added to standard chemotherapy has been shown to improve clinical outcome. NTG is hypothesized to increase tumor blood flow and may augment drug delivery to the tumor and diminish tumor hypoxia causing a decrease in VEGF. High circulating VEGF is a prognostic factor for unfavourable outcome. We showed that adding NTG to PCB (PCB + N) did not improve progression free survival (PFS), response rate (RR) and overall survival (OS) in pts with stage IV NS-NSCLC (NCT01171170; Dingemans, ASCO 2014). Here we present impact of baseline VEGF on clinical outcome. Methods: In this open-label multicenter phase II trial chemo-naive pts with stage IV NS-NSCLC were randomized 1:1 to PCB or PCB + N. Pts were treated with P 200 mg/m2 day (d) 1-C AUC 6 d1-B 15 mg/kg d1 every 3 weeks (wks) or PCB + NTG 15 mg/24 h for 5 d (d -2 to +3) every cycle for 4 cycles and B + N until progression. The study was powered (80%) to detect a decrease in the hazard of progression of 33% at a = 0.05 with a two-sided log rank test. As pre-planned exploratory analysis baseline, wks 3 and 6 free circulating VEGF levels by ELISA were assessed. Results: 223 pts were randomized; 112 PCB and 111 PCB + N; Median (95% CI) PFS in PCB was 6.8 months (m) (5.6-7.3) and 5.0 m (4.2-5.8) in PCB + N, HR 1.22 (0.91-1.63). OS was 11.6 m (8.7-14) in PCB and 9.5 m (7.8-11.9) in PCB + N, HR 1.12 (0.76-1.67). Baseline median VEGF (n = 178) was 111 pg/ml (inter-quartile range 55-218), equal between 2 arms. High VEGF levels (n = 89) at baseline was associated with worse OS (p = 0.02) and PFS (p = 0.0003). For pts with above median VEGF at baseline, OS and PFS were not different for PCB and PCB + N, for pts with below median VEGF there was a trend for worse PFS HR 1.46 (0.95 – 2.24) and OS HR1.55 (0.97-2.49) in the pts treated with PCB + N. In both arms VEGF became undetectable or very low at 3 and 6 wks. Conclusions: Adding NTG to first line PCB does not improve PFS and OS in pts with stage IV NS-NSCLC. As the mechanism of action of NTG is presumably through the VEGF pathway, decrease of VEGF levels by B may preclude an additional effect of NTG. Disclosure: A.C. Dingemans: advisory board Roche; H.J.M. Groen: advisory board roche E.F. Smit: advisory board roche; J.G. Aerts: advisory board roche. All other authors have declared no conflicts of interest.

In vitro differentiation of human tooth germ stem cells into endothelial- and epithelial-like cells.

Current clinical techniques in dental practice include stem cell and tissue engineering applications. Dental stem cells are promising primary cell source for mainly tooth tissue engineering. Interaction of mesenchymal stem cell with epithelial and endothelial cells is strictly required for an intact tooth morphogenesis. Therefore, it is important to investigate whether human tooth germ stem cells (hTGSCs) derived from wisdom tooth are suitable for endothelial and epithelial cell transformation in dental tissue regeneration approaches. Differentiation into endothelial and epithelial cell lineages were mimicked under defined conditions, confirmed by real time PCR, western blotting and immunocytochemical analysis by qualitative and quantitative methods. HUVECs and HaCaT cells were used as positive controls for the endothelial and epithelial differentiation assays, respectively. Immunocytochemical and western blotting analysis revealed that terminally differentiated cells expressed cell-lineage markers including CD31, VEGFR2, VE-Cadherin, vWF (endothelial cell markers), and cytokeratin (CK)-17, CK-19, EpCaM, vimentin (epithelial cell markers) in significant levels with respect to undifferentiated control cells. Moreover, high expression levels of VEGFR1, VEGFR2, VEGF, CK-18, and CK-19 genes were detected in differentiated endothelial and epithelial-like cells. Endothelial-like cells derived from hTGSCs were cultured on Matrigel, tube-like structure formations were followed as an indication for functional endothelial differentiation. hTGSCs successfully differentiate into various cell types with a broad range of functional abilities using an in vitro approach. These findings suggest that hTGSCs may serve a potential stem cell source for tissue engineering and cell therapy of epithelial and endothelial tissue.

An in vitro retinoblastoma human triple culture model of angiogenesis: A modulatory effect of TGF-β

Retinoblastoma is the most common intraocular tumour in children. In view of understanding the molecular mechanisms through which angiogenic switch on happens in the early phases of reciprocal interaction between tumour and cells constituting retinal microvessel, Transwell co-cultures constituted by human retinal endothelial cells (HREC), pericytes (HRPC), and human retinoblastoma cell line Y-79 were performed. Y-79 enhanced HREC proliferation, reduced by the introduction of HRPC in triple culture. In HREC/HRPC cultures, TGF-β in media increased, decreasing in triple cultures. High VEGF levels in triple cultures witnessed the establishment of a strongly in vitro angiogenic environment. Y-79 induced in HREC an increase in c- and iPLA2, phospho-cPLA2, inducible COX-2 protein expressions, PLA2 activities and prostaglandin E2 (PGE2) release. These effects were attenuated when HRPC were introduced in triple culture. Moreover, antibody silencing of TGF-β demonstrated a strong correlation between the signalling pathway triggered by TGF-β of pericytal origin and the phospholipase activation and the modulation of PGE2 release. Inhibiting VEGFA effect, the HRPC loss in triple culture decreased, showing its modulatory effect on their survival. Relying on the data here presented, sustaining the pericytal survival in a tumour retinal environment could ensure the integrity of microvessels and the TGF-β supply, essential for controlling aberrant endothelial pruning and angiogenesis.

Abstract 131: Age dependent regenrative ability of ckit+ cells Derived from Neonatal and adult Hearts

Background: Human adult c-kit + cardiac stem cells (CSCs) alleviates post-myocardial infarction left ventricle dysfunction in animal models and a Phase I clinical study. The regenerative capacity of CSCs in the very young patients with non-ischemic congenital heart defects has not been explored, even in the most surgically challenging Hypoplastic Left Heart Syndrome (HLHS) patients. We hypothesized that isolated neonatal-derived ckit + CSCs have higher regenerative abilities than adult-derived CSCs and might address the anatomical deficiency of HLHS myocardium. Methods and Results: Human specimens were obtained during routine cardiac surgical procedures from right atrial appendage tissue discarded from 2 age groups: neonates and adults patients. We developed a reproducible isolation method that generated c-kit + cells using immune-activated magnetic bead selection, regardless of the initial weight or age. More than 85% ckit+ cells were isolated from both groups and these cells were negative for tryptase, collagen, CD45, CD34 and CD31. Single cell proliferation assay showed neonatal ckit+ cells are significantly more proliferative compare to adult ckit + cells. Neonatal c-kit + cells showed significantly higher telomere length (p=0.0286) compare to Adult. The neonatal-derived c-kit + cells secreted higher levels of VEGF-A, ANG, and SDF-1α when compared to adult-derived c-kit + cells. When transplanted into infarcted myocardium, neonatal-derived c-kit + cells had a significantly higher ability to preserve myocardial function, prevent adverse remodeling, and enhance blood vessel preservation when compared to adult-derived c-kit + CSCs. . Treatment with Neonatal-derived ckit + cells also augmented the preservation/formation of neovessels (isolectin B4) and arterioles (α-SMA) compared to adult-derived ckit + cells Conclusions: Neonatal-derived c-kit + cells have a strong regenerative ability when compared with adult-derived c-kit + cells that may depend on angiogenic cytokines. This has important implications in the potential use of CSCs in future HLHS clinical trials.

Analysis of Primary Urethral Wound Healing in the Rat

To analyze the process of urethral healing, which is the basis of urethral reconstructive surgery but remains poorly understood, we have developed a rat model of urethroplasty. Understanding this process may provide strategies to prevent aberrant urethral healing and improve the healing process. We performed urethroplasties on 36 male Sprague-Dawley rats. On postoperative days 2, 4, 6, 8, 10, and 12, animals were sacrificed. The number of neutrophils, macrophages, fibroblasts, blood vessels, and Ki67 proliferative index was evaluated with immunostaining and collagen I and III contents with picrosirius staining. Expression of VEGF, PDGF, TNFα, TGFβ, and FGF was analyzed with quantitative real-time PCR. Urethral healing occurs in phases of inflammation, proliferation, maturation, and remodeling analogous to dermal healing, however, with extended duration of each phase. The inflammatory phase reached to postoperative day 4 being characterized by neutrophil and macrophage predominance and high levels of VEGF, PDGF, TGFβ, TNFα, and IL-10. The proliferative phase extended until day 10 characterized by myofibroblast proliferation and angiogenesis. Maturation and remodeling started on day 10 with decreasing proliferation and angiogenesis, increasing collagen I formation, and periurethral alignment of connective tissue. The healing process involved >50% of the periurethral/spongiosum area in the inflammatory and >80% in the maturation and remodeling phase. Urethral healing occurs in phases similar to those observed in dermal healing, however, with extension of each phase. The healing process is not limited to the site of injury but involves the vast majority of periurethral tissue and corpus spongiosum. This appears to be the result of the unique anatomical features of the urethra.

Osteoblast-secreted factors promote proliferation and osteogenic differentiation of bone marrow stromal cells via VEGF/heme-oxygenase-1 pathway.

The hypoxia-inducible factors (HIFα) are the critical factors that couple angiogenesis and osteogenesis by activating transcription of VEGF in osteoblasts. Mice lacking von Hippel–Lindau gene (Vhl), thus overexpressing HIFα in osteoblasts develop extremely dense and highly vascularized long bones. Here we provide evidence that osteoblasts lacking Vhl overexpress and secrete high levels of VEGF, which subsequently promotes the proliferation and osteogenic differentiation of bone marrow stromal cells (BMSC) by promoting expression of Heme oxygenase-1 (HO-1) in BMSC. Conditioned medium from osteoblasts Vhl (CM-CRE) promoted the proliferation and osteogenic differentiation of BMSC, in comparison with conditioned medium derived from normal osteoblasts (CM-GFP). Recombinant VEGF stimulated the proliferation and osteogenic differentiation of BMSC culturing in CM-GFP. By contrast, VEGF-neutralizing antibody inhibited the proliferation and osteogenic differentiation of BMSC culturing in CM-CRE. Treatment with a HO-1 inhibitor, SnPP, significantly inhibited VEGF-induced BMSC proliferation and osteogenic differentiation. On the contrary, activation of HO-1 with CoPP reversed the suppressing of VEGF-antibody on the proliferation and osteogesis of BMSC culturing in CM-CRE. These studies suggest that osteoblasts promote the proliferation and osteogenic differentiation of BMCS by VEGF/HO-1 pathway.

Serum level and immunohistochemical expression of vascular endothelial growth factor for the prediction of postoperative recurrence in renal cell carcinoma.

BackgroundVascular endothelial growth factor (VEGF) plays a major role in angiogenesis. One of the functions of VEGF is to regulate neovascularization in clear cell renal cell carcinoma (CCRCC). The objective of our study was to examine whether before nephrectomy serum levels of VEGF or expression of VEGF using immunohistochemistry (IHC) could predict postoperative recurrence in nonmetastatic CCRCC.ResultsTwelve patients (14.5%) had recurrence during a mean follow-up of 52.6 ± 31.2 months. The serum VEGF level was significantly higher in patients with recurrence than in those without recurrence (P = 0.038). High serum VEGF levels were above 416 pg/mL; this value was chosen based on a receiver operating characteristic analysis. The recurrence-free survival rate in patients with a high serum VEGF level was significantly lower than in those with a low serum VEGF level (P = 0.003). In total, tumors from 26 patients (31.3%) showed overexpression of VEGF using IHC. The recurrence-free survival rate in the IHC-positive group was significantly lower than that in the IHC-negative group (P = 0.044). Multivariate analysis indicated that preoperative serum VEGF levels (P = 0.013) and female gender (P = 0.004) were independent predictors of postoperative recurrence in nonmetastatic CCRCC.ConclusionsPreoperative serum VEGF levels is a useful predictor compared with IHC analysis of VEGF of postoperative recurrence in nonmetastatic CCRCC.

Quantitative expression of serum biomarkers involved in angiogenesis and inflammation, in patients with glioblastoma multiforme: correlations with clinical data.

Glioblastoma multiforme (GBM) represents a very aggressive brain tumor. Angiogenesis is the formation of a network of new blood vessels, from preexisting ones. It plays an important role in the formation of the tumor, as it supplies it with oxygen and nutrients. Angiogenesis and inflammation play essential roles in glioblastoma development. These processes are regulated by the balance of a few molecules, acting as pro- or antiangiogenic and pro- or anti-inflammatory factors. The purpose of our study was to evaluate the expression of 7 markers involved in angiogenesis and inflammation pathways in patients with glioblastoma. VEGF, PDGF-bb, IGF-1, TGF-β, TNF-α, IL-6 and IL-8 levels were measured using the ELISA method, in the preoperative sera of 14 patients with histopathologically confirmed glioblastoma multiforme and 32 healthy patients. Serum levels of PDGF-bb, IGF-1 and IL-8 were significantly higher in patients with GBM, compared to the control group (p-value < 0.01). A statistically significant correlation has been found between IGF-1 and IL-6 levels (rho= -0.53, p-value < 0.05) and also between TNF-α and IL-6 levels (rho=0.60, p-value < 0.05). Statistically significant associations have been found between the presence of low levels of IL-8 and the development of coagulation necrosis (p-value < 0.05), high levels of VEGF and development of ischemic necrosis (p-value < 0.01) and high levels of IL-8 and the development of endothelial hyperplasia (p-value < 0.05). We have observed no statistically significant associations between the serum levels of the markers and the survival rates.

Bidirectional crosstalk between periventricular endothelial cells and neural progenitor cells promotes the formation of a neurovascular unit

Interactions between neural progenitor cells (NPC) and endothelial cells (EC) from adult vascular beds have been well explored previously. However, the factors and signaling mechanisms that regulate neurogenesis and angiogenesis are most prevalent during embryonic development. This study aimed to determine whether embryonic brain endothelial cells from the periventricular region (PVEC) present an advantage over adult brain EC in supporting NPC growth and differentiation. PVEC were isolated from E15 mouse brains, processed, and sorted with immunomagnetic beads using antibodies against CD31/PECAM. On immunofluorescence (IF) staining, nearly all cells were positive for EC markers CD31 and CD144/VE-Cadherin. In proliferation studies, NPC proliferation was highest in transwell co-culture with PVEC, approximately 2.3 fold increase compared to baseline versus 1.4 fold increase when co-cultured with adult brain endothelial cells (ABEC). These results correlated with the PVEC mediated delay in NPC differentiation, evidenced by high expression of progenitor marker Nestin evaluated by IF staining. Upon further characterization of PVEC in an angiogenesis assay measuring cord length, PVEC exhibited a high capacity to form cords in basal conditions compared to ABEC. This was enhanced in the presence of NPC, with both cell types displaying a preferential structural alignment resembling neurovascular networks. PVEC also expressed high Vegfa levels at baseline in comparison to NPC and ABEC. Vegfa levels increased when co-cultured with NPC. We demonstrate that PVEC and NPC co-cultures act synergistically to promote the formation of a neurovascular unit through dynamic and reciprocal communication. Our results suggest that PVEC/NPC could provide promising neuro-regenerative therapies for patients suffering brain injuries.

4-Phenylbutyric acid suppresses inflammation through regulation of endoplasmic reticulum stress of endothelial cells stimulated by uremic serum

AimsEndoplasmic reticulum (ER) stress is involved in the pathogenesis of atherosclerosis (AS). Endothelial cell (EC) dysfunction and monocyte migration to the subendothelium are considered to be essential manifestations of AS. We conducted this study to determine whether ER stress was involved in uremic serum-induced EC dysfunction and whether the regulation of ER stress using a chemical chaperone 4-phenylbutyric acid (4-PBA) had a preventative effect. Main methodsHuman umbilical vein endothelial cells (HUVECs) were divided into 4 groups: a control serum group (C.S), a uremic serum group (U.S), a uremic serum plus 4-PBA (5mM) treatment group (4-PBA), and a uremic serum plus pyrrolidine dithiocarbamate (PDTC:50μM) treatment group (PDTC). Key findingsLower concentrations of uremic serum (<10%) facilitated the proliferation of HUVECs. In contrast, the proliferative capability of HUVECs was gradually decreased when we continuously increased the concentration of uremic serum. Compared with C.S, HUVEC incubation with uremic serum had high expression levels of GRP78, p-PERK, NF-κB, MCP-1, and VEGF. THP-1 migration was markedly higher than C.S over the indicated time. These alterations were inhibited by the administration of 4-PBA. SignificanceThese findings suggest that regulation of ER stress coupled with inflammatory activation by 4-PBA would be a promising therapy to reverse the process and development of uremic serum-induced EC dysfunction.

High Serum Levels of Vascular Endothelial Growth Factor-A and Transforming Growth Factor-β1 Before Neoadjuvant Chemoradiotherapy Predict Poor Outcomes in Patients with Esophageal Squamous Cell Carcinoma Receiving Combined Modality Therapy

This study was aimed at using proximity ligation assay (PLA) followed by enzyme-linked immunosorbent assay (ELISA) to identify serum biomarkers that predict treatment response and survival for patients with esophageal squamous cell carcinoma (ESCC) undergoing neoadjuvant concurrent chemoradiotherapy (CCRT) followed by esophagectomy. Seventy-nine patients with ESCC receiving CCRT of taxane-based/5-fluorouracil-based chemotherapy and 40 Gy followed by surgery were enrolled. Serum samples were collected before and <1 month after CCRT. Fifteen biomarkers were analyzed using PLA. Biomarkers significantly correlating with pathological response/survival were verified by ELISA. Associations of the serum level of biomarkers and clinical factors with pathological response, disease-free survival (DFS), and overall survival (OS) were evaluated by analysis of variance and log-rank tests. Thirty patients had complete response (38 %), 37 had microscopic residual disease (47 %), and 12 had macroscopic residual disease (15 %). With a median follow-up of 52.8 months, the median DFS was 43 months. Among the 15 biomarkers screened by PLA, vascular endothelial growth factor (VEGF)-A and transforming growth factor (TGF)-β1 were significantly associated with pathological response and/or DFS. These biomarkers were further analyzed by ELISA to confirm initial biomarker findings by PLA. After ELISA of these two markers, only VEGF-A levels were significantly correlated with pathological response. On multivariate analysis, patients with combined high pre-CCRT VEGF-A and TGF-β1 levels (greater than or equal to the median), independent of pathological response, had significantly worse DFS (11 months vs. median not reached; p = 0.007) and OS (16 vs. 46 months; p = 0.07). Pre-CCRT serum VEGF-A and TGF-β1 levels may be used to predict pathological response and survivals for ESCC patients receiving combined-modality therapy.

Association of polymorphisms in the vascular endothelial growth factor gene and its serum levels with diabetic retinopathy in Chinese patients with type 2 diabetes: A cross-sectional study

Background Vascular endothelial growth factor (VEGF) is a major mediator of angiogenesis, and plays a key role in the pathogenesis of diabetic retinopathy (DR). This study was designed to identify the possible role of VEGF gene polymorphisms in the development of DR in type 2 diabetic patients in Chinese and clarify the relationship between VEGF serum levels and the risk of DR. Methods This cross-sectional study included 1 040 Chinese subjects with type 2 diabetes mellitus. There were 372 patients diagnosed with DR in the case group and 668 patients without DR in the control group. DNA from each patient was analyzed for VEGF polymorphisms of -2578A/C (rs699947), -1154G/A (rs1570360), -460C/T (rs833061), +405C/G (rs2010963), and +936C/T (rs3025039) using MassARRAY compact analyzer. The VEGF serum levels were quantified by enzyme-linked immunosorbent assay (ELISA). Results No evidence of association was observed between -2578 A/C (rs699947), +405C/G (rs2010963), +936C/T (rs3025039), and DR risk under stringent Bonferroni's correction. However, VEGF serum levels were significantly higher in DR patients than those of control group. The genetic variation of VEGF polymorphisms influenced VEGF serum levels; subjects carrying the VEGF -2578 C/C (rs699947) genotype had greater VEGF serum levels than those carrying the C/A genotype and VEGF serum levels were significantly higher in CC genotype of the +405C/G (rs2010963) compared with those of the other genotypes. Conclusions The data did not suggest significant association between the VEGF polymorphisms and DR risk under stringent Bonferroni's correction. However, our study indicated that DR patients have higher VEGF levels than diabetic patients without retinopathy, and -2578A/C (rs699947) and +405C/G (rs2010963) may be important factors in determining serum VEGF levels.

COX-2 silencing enhances tamoxifen antitumor activity in breast cancer in vivo and in vitro

Tamoxifen (Tam), a selective estrogen receptor modulator, is in wide clinical use for the treatment and prevention of breast cancer. However, extended TAM administration for breast cancer induces increased VEGF levels in patients, promoting new blood vessel formation and thereby limiting its efficacy and highlighting the need for improved therapeutic strategies. Cyclooxygenase-2 (COX-2) silencing via a replication-incompetent lentivirus (LV-COX-2) induce cancer apoptosis and suppresses VEGF gene expression. In this study, the effect of LV-COX-2 infection, either alone or in combination with TAM, was analyzed in a breast cell lines for suppressing VEGF expression and simultaneously reducing doses of TAM. Cell proliferation, apoptosis, angiogenesis, metastasis, cell cycle distribution, an receptor signaling were determined after LV-COX-2 combination with TAM treatment. In addition, tumor growth ability in nude mice was detected to define the combination treatment effect in tumorigenesis in vivo. It is found that LV-COX-2 combination with TAM treatment in breast cancer cell significantly suppressed the proliferation and metastasis, and induced tumor apoptosis in vitro, and tumor growth also was suppressed in vivo. In addition, we also found that LV-COX-2 combination with TAM treatment could inhibit angiogenesis and VEGF expression. Taken together, our experimental results indicate that LV-COX-2 combination with TAM has promising outcome in anti-metastatic and apoptotic studies. Furthermore, these results showed that LV-COX-2 combination with TAM is a potential drug candidate for treatment of breast tumors expressing high levels of VEGF.

Thromboxane synthase expression and correlation with VEGF and angiogenesis in non-small cell lung cancer

Background: Thromboxane synthase (TXS) metabolizes prostaglandin H2 into thromboxanes, which are biologically active on cancer cells. TXS over-expression has been reported in a range of cancers, and associated with angiogenesis and poor outcome. TXS has been identified as a potential therapeutic target in NSCLC. This study examines a link between TXS expression, angiogenesis, and survival in NSCLC. Methods: TXS and VEGF metabolite levels were measured in NSCLC serum samples (n=46) by EIA. TXB2 levels were correlated with VEGF. A 204-patient TMA was stained for TXS, VEGF, and CD-31 expression. Expression was correlated with a range of clinical parameters, including overall survival. TXS expression was correlated with VEGF and CD-31. Stable TXS clones were generated and the effect of overexpression on tumor growth and angiogenesis markers was examined in-vitro and in-vivo (xenograft mouse model). Results: Serum TXB2 levels were correlated with VEGF (p<0.05). TXS and VEGF were expressed to a varying degree in NSCLC tissue. TXS was associated with VEGF (p<0.0001) and microvessel density (CD-31; p<0.05). TXS and VEGF expression levels were higher in adenocarcinoma (p<0.0001) and female patients (p<0.05). Stable overexpression of TXS increased VEGF secretion in-vitro. While no significant association with patient survival was observed for either TXS or VEGF in our patient cohort, TXS overexpression significantly (p<0.05) increased tumor growth in-vivo. TXS overexpression was also associated with higher levels of VEGF, microvessel density, and reduced apoptosis in xenograft tumors. Conclusion: TXS promotes tumor growth in-vivo in NSCLC, an effect which is at least partly mediated through increased tumor angiogenesis.