Efficacy, durability, and safety of faricimab in patients from Asian countries with neovascular age-related macular degeneration: 1-Year subgroup analysis of the TENAYA and LUCERNE trials

PURPOSE

To evaluate 1-year efficacy, durability, and safety of faricimab among patients from Asian countries in the TENAYA/LUCERNE trials of neovascular age-related macular degeneration (nAMD).

METHODS

Treatment-naïve patients with nAMD were randomly assigned (1:1) to faricimab 6.0 mg up to every 16 weeks (Q16W), based on disease activity at weeks 20 and 24, or aflibercept 2.0 mg Q8W. The primary endpoint was change in best-corrected visual acuity (BCVA) from baseline averaged over weeks 40, 44, and 48.

RESULTS

In the pooled TENAYA/LUCERNE trials, there were 120 (9.0%) and 1209 (91.0%) patients in the Asian (faricimab n = 61; aflibercept n = 59) and non-Asian country (faricimab n = 604; aflibercept n = 605) subgroups, respectively. In the Asian country subgroup, mean BCVA change from baseline at the primary endpoint visits was 7.1 (95% CI, 4.3-9.8) letters with faricimab and 7.2 (4.4-10.0) letters with aflibercept. In non-Asian country patients, mean vision gains were 6.1 (5.2-7.1) and 5.7 (4.8-6.7) letters with faricimab and aflibercept, respectively. At week 48, 59.6% of Asian country patients in the faricimab group achieved Q16W dosing (vs. 43.9% non-Asian) and 91.2% achieved ≥ Q12W dosing (vs. 77.5% non-Asian). Central subfield thickness reductions were similar between the subgroups, with meaningful and similar reductions from baseline observed at the primary endpoint visits and over time. Faricimab was well tolerated in both subgroups, with an acceptable safety profile.

CONCLUSION

Consistent with the global TENAYA/LUCERNE findings, faricimab up to Q16W showed sustained visual and anatomical benefits in patients with nAMD from Asian and non-Asian countries.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03823287 (TENAYA); NCT03823300 (LUCERNE). Date of registration: January 30, 2019.

PRMT5 promotes retinoblastoma development

Epigenetic mechanism, including DNA methylation and histone modifications, contributes to alterations in the expression patterns of genes regulating malignant phenotype of cancer cells. However, the epigenetic modulation of vascular endothelial growth factor-A (VEGFA) in retinoblastoma (RB) has not been clearly established. We aimed to examine the epigenetic regulation of VEGFA by protein arginine methyltransferase 5 (PRMT5) in RB. Using the GEO database, we identified VEGFA as a pathogenic gene in RB. Silencing of VEGFA in SO-RB50 and Y79 cells inhibited cell proliferation, angiogenesis, and migration, promoted apoptosis, and suppressed tumor growth in mice. Mechanistically, PRMT5 promoted H3K4me3 modification of the VEGFA promoter, thereby activating VEGFA expression. VEGFA could regulate the expression of MMP1, MMP2, and MMP9. Further silencing of VEGFA in RB cells overexpressing PRMT5 constrained the expression of MMP1, MMP2 and MMP9, and suppressed the growth of tumors in mice. In conclusion, this study clarifies that the depletion of PRMT5 reduces H3K4me3-mediated VEGFA transcription and retards the carcinogenesis of RB by suppressing the expression of MMPs.

Angiogenic factors measured in aspirated placental tissue between the 10 + 6 and 18 + 3 weeks of gestation

This study was designed to determine the level of vascular endothelial growth factor-A (VEGF-A), basic fibroblast growth factor (bFGF) and endothelial nitric oxide synthase (eNOS) in chorionic villi during in first and second trimester, and their association with nuchal translucency (NT) measured by ultrasound. Seventy-five singleton healthy pregnancies with no detected congenital malformation were collected for NT measurements and chorionic villus sampling (CVS). Concentrations of angiogenic factors were assayed in chorionic villi sampled between 10 + 6 and 18 + 3 weeks of gestation. ENOS level was steady during this gestational period, while the concentrations of VEGF-A and bFGF significantly decreased. Placental concentrations of VEGF-A and bFGF correlated positively with each other (semi-partial correlation in multivariable linear regression (r): 0.90) and both correlated negatively with the eNOS level (r: -0.64 and r: -0.83, respectively). NT was positively correlated with eNOS concentration and negatively correlated with bFGF levels (r: 0.85 and r: -0.78, respectively). Inverse correlation was found between gestational age and VEGF-A and bFGF concentrations (r: -0.57 and r: 0.73, respectively). Alterations of angiogenic factors in chorionic villi might be an adjunct modality to NT and foetal growth as sonographic markers.

Alginic acid inhibits non-small cell lung cancer-induced angiogenesis via activating miR-506 expression

Angiogenesis is a key event in non-small cell lung cancer progression. Alginic acid (AA), a kind of naturally occurring polyuronic acid, is generally enriched in edible brown algae. Recent studies have uncovered its anti-anaphylactic and anti-inflammatory properties. However, the effects of AA on human malignancies remain unknown. Herein, efficient inhibition of AA on NSCLC-induced angiogenesis was observed with tube formation and xenograft models. Subsequent results indicated that AA downregulated the expression of VEGF-A, a key angiogenesis-inducing cytokine. In addition, AA downregulated STAT3, a transcriptional inducer of VEGF-A and increased non-coding RNA miR-506 expression, respectively. Furthermore, miR-506 directly modulated STAT3 relying on base pairing the 3'-UTR in STAT3 mRNA. We also found that abrogation of miR-506 abolished the inhibitory effect of AA on VEGF-A expression and NSCLC-induced angiogenesis. Finally, xenografts experiments also showed that oral administration of AA could significantly attenuate NSCLC angiogenesis, indicated by decreased micro-vessel density (MVD) and the MVD marker CD31 expression in xenografts tissues. Correspondingly, AA treatment also downregulated VEGF-A, STAT3 and increased miR-506 expression in xenografts samples, respectively. Taken together, these results suggested that AA could suppress NSCLC-induced angiogenesis via miR-506/STAT3/VEGF-A axis. .

Fork head box M1 regulates vascular endothelial growth factor-A expression to promote the angiogenesis and tumor cell growth of gallbladder cancer

BACKGROUND

Gallbladder cancer (GBC) is an aggressive type of biliary tract cancer that lacks effective therapeutic targets. Fork head box M1 (FoxM1) is an emerging molecular target associated with tumor progression in GBC, and accumulating evidence suggests that vascular endothelial growth factor (VEGF) promotes various tumors by inducing neoangiogenesis.

AIM

To investigate the role of FoxM1 and the angiogenesis effects of VEGF-A in primary GBC.

METHODS

Using immunohistochemistry, we investigated FoxM1 and VEGF-A expression in GBC tissues, paracarcinoma tissues and cholecystitis tissues. Soft agar, cell invasion, migration and apoptosis assays were used to analyze the malignant phenotype influenced by FoxM1 in GBC. Kaplan-Meier survival analysis was performed to evaluate the impact of FoxM1 and VEGF-A expression in GBC patients. We investigated the relationship between FoxM1 and VEGF-A by regulating the level of FoxM1. Next, we performed MTT assays and Transwell invasion assays by knocking out or overexpressing VEGF-A to evaluate its function in GBC cells. The luciferase assay was used to reveal the relationship between FoxM1 and VEGF-A. BALB/c nude mice were used to establish the xenograft tumor model.

RESULTS

FoxM1 expression was higher in GBC tissues than in paracarcinoma tissues. Furthermore, the high expression of Foxm1 in GBC was significantly correlated with a malignant phenotype and worse overall survival. Meanwhile, high expression of FoxM1 influenced angiogenesis; high expression of FoxM1 combined with high expression of VEGF-A was related to poor prognosis. Attenuated FoxM1 significantly suppressed cell proliferation, transfer and invasion in vitro. Knockdown of FoxM1 in GBC cells reduced the expression of VEGF-A. Luciferase assay showed that FoxM1 was the transcription factor of VEGF-A, and knockdown VEGF-A in FoxM1 overexpressed cells could partly reverse the malignancy phenotype of GBC cells. In this study, we found that FoxM1 was involved in regulation of VEGF-A expression.

CONCLUSION

FoxM1 and VEGF-A overexpression were associated with the prognosis of GBC patients. FoxM1 regulated VEGF-A expression, which played an important role in the progression of GBC.

miR-126-3p and miR-16-5p as novel serum biomarkers for disease activity and treatment response in symptomatic dermographism

Symptomatic dermographism (SD) is the most common form of physical urticaria. So far no promising serum biomarkers for SD have been reported. Recently, microRNAs (miRNAs) have been reported to be serum biomarkers for chronic spontaneous urticaria. However, association of miRNAs with SD remains unclear. We enrolled 55 SD patients and 52 healthy controls in this study. We found that serum expressions of miR-126-3p and miR-16-5p were significantly downregulated in active SD patients and upregulated in remission. The area under the curve values of miR-126-3p (0.769) and miR-16-5p (0.789) showed significant ability to diagnostic SD. Serum level of vascular endothelial growth factor (VEGF)-A, a known target of the two miRNAs, was significantly increased in active SD patients and decreased in remission. Moreover, serum VEGF-A level was inversely correlated with expressions of miR-126-3p and miR-16-5p. Our findings indicate that miR-126-3p and miR-16-5p can serve as potential serum biomarkers for SD.

Vascular Endothelial Growth Factor-A Is Associated with Platelets and Complement 4 in Patients with Primary Sjögren's Syndrome

OBJECTIVE

We aimed at investigating the expression level of vascular endothelial growth factor-A (VEGF-A) in patients with primary Sjögren's Syndrome (pSS) and evaluating the relationship between serum VEGF-A and the laboratory indicators that are associated with it in pSS.

METHODS

The VEGF-A levels were measured by ELISA in a total of 88 participants, including 58 patients with pSS and 30 healthy people. The VEGF-A levels between two groups were analyzed.

RESULTS

The serum levels of VEGF-A in pSS and control groups were 175.50 (112.00,296.50) pg/mL and 181.50 (155.25,288.50) pg/mL, without statistically significant difference. The associations were found between serum levels of VEGF-A with C reactive protein (CRP) (r=0.265, P<0.05), white blood cells (WBC) (r=0.302, P<0.05), neutrophils (NEUT) (r=0.349, P<0.05), platelets(PLT) (r=0.276, P<0.05), complement 3 (C3) (r=0.477, P<0.05), complement 4 (C4) (r=0.387, P<0.05) and CA19-9 (r=0.392, P<0.05). Among these laboratory indicators, VEGF-A was correlated with platelets and complement 4 in patients with pSS.

CONCLUSIONS

In patients with pSS, the levels of VEGF-A were independently influenced by the levels of platelet and complement 4, which indicated the intermodulation between the growth factor and immune system in the autoimmune disease.

Dietary patterns and relative expression levels of PPAR-γ, VEGF-A and HIF-1α genes in benign breast diseases: case-control and consecutive case-series designs

We aimed to study dietary patterns in association with the relative expression levels of PPAR-γ, vascular endothelial growth factor-A (VEGF-A) and hypoxia-inducible factor-1α (HIF-1α) in women with benign breast disease (BBD). The study design was combinative, included a case-series and case-control compartments. Initially, eligible BBD patients (n 77, aged 19-52 years old) were recruited at Nour-Nejat hospital, Tabriz, Iran (2012-2014). A hospital-based group of healthy controls was matched for age (n 231, aged 20-63 years old) and sex. Dietary data were collected using a valid 136-item FFQ. Principal component analysis generated two main components (Kaiser-Meyer-Olkin = 0·684), including a Healthy pattern (whole bread, fruits, vegetables, vegetable oils, legumes, spices, seafood, low-fat meat, skinless poultry, low-fat dairy products, nuts and seeds) and a Western pattern (starchy foods, high-fat meat and poultry, high-fat dairy products, hydrogenated fat, fast food, salt and sweets). High adherence to the Western pattern increased the risk of BBD (ORadj 5·59; 95 % CI 2·06, 15·10; P < 0·01), whereas high intake of the Healthy pattern was associated with a 74 % lower risk of BBD (95 % CI 0·08, 0·81; P < 0·05). In the BBD population, the Western pattern was correlated with over-expression of HIF-1α (radj 0·309, P < 0·05). There were inverse correlations between the Healthy pattern and expressions of PPAR-γ (radj -0·338, P < 0·05), HIF-1α (radj -0·340, P < 0·05) and VEGF-A (radj -0·286, P < 0·05). In conclusion, new findings suggested that the Healthy pattern was associated inversely with the risk of BBD, and this could be correlated with down-regulation of PPAR-γ, VEGF-A and HIF-1α genes, which might hold promise to preclude BBD of malignant pathological transformation.

4'-hydroxywogonin inhibits colorectal cancer angiogenesis by disrupting PI3K/AKT signaling

Angiogenesis is fundamental for solid tumor growth and metastasis, and anti-angiogenic therapy has been an important therapeutic option for cancer treatment. Colorectal cancer (CRC) represents the fourth leading cause of cancer-related death worldwide. The current studies were aimed at investigating the anti-angiogenic effects of the natural compound 4'-hydroxywogonin (4'-HW) on CRC-related angiogenesis. Human CRC cell line SW620 cells and normal human intestinal epithelial HIEC cells were cultured and treated with interleukin-6 to mimic the tumor inflammatory microenvironment. Our data showed that 4'-HW reduced the viability of SW620 cells in a concentration- and time-dependent manner. 4'-HW also suppressed the proliferation of SW620 cells, but had little effect on the viability of HIEC cells. Moreover, 4'-HW concentration-dependently decreased the mRNA and protein expression of vascular endothelial growth factor-A (VEGF-A), the predominant pro-angiogenic cytokine in tumor angiogenesis. Subsequently, 4'-HW concentration-dependently inhibited the phosphorylation of phosphatidylinositol 3-kinase (PI3K) and AKT. PI3K inhibitor wortmannin, similar to 4'-HW, significantly downregulated the VEGF-A expression in SW620 cells, and combination of wortmannin and 4'-HW produced more significant effects. Finally, human umbilical vein endothelial cells (HUVECs) incubated with the conditioned medium of 4'-HW-treated SW620 cells exhibited impaired angiogenic capacity at Matrigel. Incubation with the neutralizing antibody against VEGF-Aalone also suppressed the angiogenic properties of HUVECs in vitro. Collectively, 4'-HW decreased the viability and reduced angiogenesis in CRC, which was associated with downregulation of VEGF-A expression by disrupting the PI3K/AKT pathway. Our discoveries suggested 4'-HW as a promising anticancer agent against CRC targeting angiogenesis.

Balance between angiogenic and anti-angiogenic isoforms of VEGF-A is associated with the complexity and severity of coronary artery disease

INTRODUCTION

Assessing the complexity of coronary artery disease (CAD) is clinically important. Vascular endothelial growth factor A (VEGF-A) is a powerful and the most important regulator of angiogenesis. It has been reported that the anti-angiogenic isoform of VEGF-A (VEGF-A₁₆₅b) inhibits angiogenesis. The purpose of this study was to evaluate the relationship between the complexities of CAD using the Syntax score (SS) and the levels of circulating total VEGF-A or VEGF-A₁₆₅b.

METHODS

A total of 268 patients who underwent percutaneous coronary intervention (PCI) were enrolled. Of these, 73 patients without acute coronary syndrome or previous revascularization were included in this study. These subjects were divided into two groups according to the SS. Circulating total VEGF-A and VEGF-A₁₆₅b levels were measured using an enzyme-linked immunosorbent assay.

RESULTS

Circulating levels of total VEGF-A were significantly higher in the SS>22 (high SS) group than in the SS≤22 (low SS) group (p=0.018). Moreover, the ratio of VEGF-A₁₆₅b to total VEGF-A was significantly lower for the high SS group (p=0.004). The levels of total VEGF-A independently predicted high SS after adjusting for other significant variables among patients who underwent PCI (odds ratio, 1.004; 95% CI, 1.001 to 1.006; p=0.01).

CONCLUSIONS

These data indicated that high SS was associated with circulating levels of total VEGF-A and the ratio of VEGF-A₁₆₅b to total VEGF-A in patients with complex CAD.

Advanced glycation end products induced IL-6 and VEGF-A production and apoptosis in osteocyte-like MLO-Y4 cells by activating RAGE and ERK1/2, P38 and STAT3 signalling pathways

Advanced glycation end products (AGEs) are involved in osteopenia in people with diabetes and the elderly. Interleukin-6 (IL-6) and vascular endothelial growth factor-A (VEGF-A) are potent regulators of bone metabolism, and in bone tissue, osteocytes are an important source of these regulators. However, whether AGEs can directly regulate IL-6 and VEGF-A secretion by osteocytes is unknown. In this study, we evaluated the effect of AGEs on IL-6 and VEGF- A production as well as apoptosis in osteocyte-like MLO-Y4 cells. We also studied the involvement of receptor for advanced glycation end products (RAGE) and the role of extracellular signal-regulated kinases 1 and 2 (ERK1/2), P38 and signal transducer and activator of transcription 3 (STAT3) signalling pathways. We found that 100μg/ml AGEs significantly induced apoptosis and up-regulated the expression of IL-6 and VEGF-A in MLO-Y4 cells. Additionally, AGEs significantly activated the ERK1/2, P38 and STAT3 signalling pathways. The ERK1/2 inhibitor U0126, the P38 inhibitor SB239063 and the STAT3 inhibitor S3I-201 all attenuated the effects of AGEs on MLO-Y4 cell apoptosis and IL-6 and VEGF-A secretion. Moreover, activation of the three signalling pathways was abolished by their respective inhibitors. Additionally, the AGEs-induced effects, including increased apoptosis, up-regulated expression of IL-6 and VEGF-A and activation of the three signalling pathways, were all abolished by pre-treating the osteocytes with the RAGE antagonist FPS-ZM1. Together, these data convince us that AGEs can activate the ERK1/2, P38 and STAT3 signalling pathways via RAGE and that their activation involves the AGEs-induced up-regulation of IL-6 and VEGF-A production as well as apoptosis in osteocytes. These results highlight the role of osteocytes in the regulation of bone metabolism by AGEs.

Vascular endothelial growth factor-A gene polymorphism is associated with congenital renal lesions in children with urinary tract infections

AIM

This study investigated the relationship between vascular endothelial growth factor-A (VEGF-A)-460C/T functional gene polymorphism and renal parenchymal lesions, vesicoureteral reflux and other urinary tract abnormalities in children with a urinary tract infection (UTI).

METHODS

VEGF-A-460C/T gene polymorphism was investigated with restriction length polymorphism analysis in 76 children with their first UTI and in 63 controls without infections. Genotype and allele frequencies were compared between children with UTIs and controls and between different groups with UTIs.

RESULTS

The VEGF-A-460C/T genotype frequencies differed significantly between those with and without renal parenchymal lesions in the UTI cohort. Allele C homozygosity was significantly more common in those with renal parenchymal lesions (36.6% versus 8.7%, p = 0.007). A separate analysis showed that allele C was associated with lesions compatible with hypodysplasia, rather than with focal ones associated with infections, with an odds ratio of 11.55 and 95% confidence interval of 3.03-43.9 (p = 0.0001). No significant differences in genotypes or allele frequencies were found between children with and without reflux or other urinary tract anomalies.

CONCLUSION

In children with UTIs, C allele polymorphism of the VEGF-A gene was associated with hypodysplastic renal parenchymal lesions, which were possibly congenital and existed before the infection.

Prognostic significance of vascular endothelial growth factor polymorphisms in colorectal cancer patients

AIM

To investigate the associations of the genetic polymorphisms of vascular endothelial growth factor A (VEGF-A) -1498C>T and -634G>C, with the survival of patients with colorectal cancer (CRC).

METHODS

A prospective cohort consisting of 131 Brazilians patients consecutively operated on with a curative intention as a result of sporadic colorectal carcinoma was studied. DNA was extracted from peripheral blood and its amplification and allelic discrimination for each genetic polymorphism was performed using the technique of polymerase chain reaction (PCR) in real-time. The real-time PCR technique was used to identify the VEGF-A -1498C>T (rs833031) and -634G>C (rs2010963) polymorphisms. Genotyping was validated for VEGF-A -1498C>T polymorphism in 129 patients and for VEGF-A -634G>C polymorphism in 118 patients. The analysis of association between categorical variables was performed using logistic regression, survival by Kaplan-Meier method and multivariate analysis by the Cox regression method.

RESULTS

In the univariate analysis there was a significant association (OR = 0.32; P = 0.048) between genotype CC of the VEGF-A -1498C>T polymorphism and the presence of CRC liver metastasis. There was no association between VEGF-A -1498C>T polymorphism and VEGF-A -634G>C polymorphism with further clinical or anatomopathologic variables. The genotype CC of the VEGF-A -1498C>T polymorphism was significantly correlated with the 5-year survival (P = 0.032), but not significant difference (P = 0.27) was obtained with the VEGF-A -634G>C polymorphism with the 5-year survival in the univariate analysis. The genotype CT (HR = 2.79) and CC (HR = 4.67) of the polymorphism VEGF-A -1498C>T and the genotype CC (HR = 3.76) of the polymorphism VEGF-A -634C>G acted as an independent prognostic factor for the risk of death in CRC patients.

CONCLUSION

The CT and CC genotypes of the VEGF-A -1498C>T and the CC genotype of the VEGF-A -634C>G polymorphisms are prognostic factors of survival in Brazilians patients with sporadic colorectal carcinoma.

A polysaccharide from Sargassum thunbergii inhibits angiogenesis via downregulating MMP-2 activity and VEGF/HIF-1α signaling

A water-soluble polysaccharide (STPC2) was isolated from the boiling-water extract of Sargassum thunbergii, purified by CaCl2 precipitation and chromatography on DEAE-cellulose and Sephacryl S-300 column. It was found that STPC2, with a molecular weight of 57kD, was composed of fucose, xylose, galactose and glucuronic acid, in a ratio of 8.1: 3.8: 2.1: 1.0. Additionally, we found that STPC2 significantly inhibited endothelial cell migration and tube formation without toxicity. Moreover, STPC2 significantly inhibited lung cancer cell A549 migration and proliferation. It was found that STPC2 treatment suppressed MMP-2 gene expression at transcriptional level and enzymatic activity. Furthermore, STPC2 reduced the mRNA and protein expression of vascular endothelial growth factor-A (VEGF-A) and hypoxia-inducible factor (HIF)-1 alpha in the endothelial cells. Taken together, our findings indicated that STPC2 was a potent bioactive polysaccharide with distinct anti-angiogenesis activity against tumor migration via down-regulation of MMP-2 activity and VEGF/HIF-1α signaling pathway.

Naringenin exerts anti-angiogenic effects in human endothelial cells: Involvement of ERRα/VEGF/KDR signaling pathway

Naringenin (Nar), most abundant in oranges and tomatoes, are known for the hypocholesterolemic, anti-estrogenic, hypolipidemic, anti-hypertensive, and anti-inflammatory activities. Here, the present study was designed to investigate the in vitro and in vivo anti-angiogenesis of Nar. Inhibition of angiogenesis was determined in vitro by using proliferation, apoptosis, migration, and tube-formation assays in Nar-treated human endothelial cell. Finally, CAM assays were used to assess inhibitory effect of Nar on physiological angiogenesis in vivo. The data suggest that Nar should be a direct ERRα inhibitor capable of inhibiting angiogenesis in vitro and in vivo, including endothelial cell proliferation, survival, migration and capillary-like structures formation of HUVECs, as well as reduced neovascularization of the CAM. Furthermore, the effects exerted by Nar are cell cycle related and mediated by VEGF/KDR signaling pathway along with downregulation of certain proangiogenic inflammatory cytokines. Our data thus provide potential molecular mechanisms through which Nar manifests it as a promising anti-angiogenic and anti-cancer agent.

Down-regulation of microRNA-126-5p contributes to overexpression of VEGFA in lipopolysaccharide-induced acute lung injury

OBJECTIVES

To investigate the role of microRNA-126-5p (miR-126-5p) in acute lung injury induced by bronchial instillation of lipopolysaccharide (LPS), and to explore the potential target(s) of miR-126-5p in acute lung injury.

RESULTS

In the mice with LPS-induced acute lung injury, the level of miR-126-5p in the pulmonary tissues was decreased by 41 % whilst pulmonary vascular endothelial growth factor-A (VEGFA) doubled in its mRNA content and increased threefold in its protein level. Similar results were observed in the alveolar type II (ATII) cells treated with LPS. By using luciferase reporter assay, we found that miR-126-5p inhibited VEGFA expression by targeting its 3'-untranslated region. In addition, overexpression of miR-126-5p attenuated LPS-induced reduction of epithelial sodium channel and aquaporin 1 in ATII cells

CONCLUSIONS

MiR-126-5p was down-regulated in LPS-induced acute lung injury in mice. Thus overexpression of miR-126-5p may alleviate acute lung injury by down-regulating VEGFA.

Role of VEGF-A in angiogenesis promoted by umbilical cord-derived mesenchymal stromal/stem cells: in vitro study

BACKGROUND

Mesenchymal stromal/stem cells derived from human umbilical cord (UC-MSCs) uniquely combine properties of embryonic and postnatal MSCs and may be the most acceptable, safe, and effective source for allogeneic cell therapy e.g. for therapeutic angiogenesis. In this report we describe pro-angiogenic properties of UC-MSCs as manifested in vitro.

METHODS

UC-MSCs were isolated from human Wharton's jelly by enzymatic digestion. Presence of soluble forms of VEGF-A in UC-MSC-conditioned media was measured by ELISA. Effects of the conditioned media on human umbilical vein-derived endothelial EA.hy926 cells proliferation were measured by MTT-assay; changes in cell motility and directed migration were assessed by scratch wound healing and transwell chamber migration assays. Angiogenesis was modeled in vitro as tube formation on basement membrane matrix. Progressive differentiation of MSCs to endothelioid progeny was assessed by CD31 immunostaining.

RESULTS

Although no detectable quantities of soluble VEGF-A were produced by UC-MSCs, the culture medium, conditioned by the UC-MSCs, effectively stimulated proliferation, motility, and directed migration of EA.hy926 cells. In 2D culture, UC-MSCs were able to acquire CD31(+) endothelial cell-like phenotype when stimulated by EA.hy926-conditioned media supplemented with VEGF-A165. UC-MSCs were capable of forming unstable 2D tubular networks either by themselves or in combinations with EA.hy926 cells. Active spontaneous sprouting from cell clusters, resulting from disassembling of such networks, was observed only in the mixed cultures, not in pure UC-MSC cultures. In 3D mode of sprouting experimentation, structural support of newly formed capillary-like structures was provided by UC-MSCs that acquired the CD31(+) phenotype in the absence of exogenous VEGF-A.

CONCLUSION

These data suggest that a VEGF-A-independent paracrine mechanism and at least partially VEGF-A-independent differentiation mechanism are involved in the pro-angiogenic activity of UC-MSCs.

Abnormalities in three-dimensional capillary architecture and imbalance between vascular endothelial growth factor-A and thrombospondin-1 in soleus muscle of ovariectomized rat

Reduced ovarian hormone levels associated with menopause or ovariectomy (OVX) not only result in vascular dysfunction but also lead to structural abnormalities in capillaries. Therefore, the effect of OVX on the three-dimensional (3-D) architecture of capillary networks and the underlying molecular mechanisms were investigated in rat soleus muscle. Seven-week-old female Wistar rats were divided into the OVX and sham-treated (Sham) groups. The OVX group exhibited lower endurance exercise capacity compared to the sham group and resulted in decreased capillary diameter, number of anastomoses and capillary/anastomosis volume in soleus muscle, indicating 3-D structural abnormalities of capillary networks. Furthermore, OVX led to increased concentrations of thrombospondin-1 (TSP-1) protein and a decreased VEGF-A/TSP-1 ratio, an indicator of angio-adaptations, in soleus muscle compared with the Sham group. These results indicate OVX may induce 3-D capillary regression in soleus muscle through an imbalance between VEGF-A and TSP-1 expression, possibly associated with decreased exercise tolerance in ovariectomized rats.

Effect of zoledronate on the expression of vascular endothelial growth factor-a by articular chondrocytes and synovial cells: an in vitro study

Background

The aim of this in vitro study was to determine the effect of zoledronate, which is frequently used to treat osteoporosis, on osteoarthritis by analyzing zoledronate-induced expression of vascular endothelial growth factor-A (VEGF-A) in chondrocytes and synovial cells.

Methods

After chondrocytes and synovial cells were separated and cultured, zoledronate was added, and VEGF-A and pigment epithelium-derived factor (PEDF) expression were quantified by real-time polymerase chain reaction and Western blotting.

Results

There was no significant difference in the expression of VEGF-A mRNA in chondrocytes between the zoledronate group and the control group on the 8th day of culture. The expression of both VEGF-A and PEDF mRNA in synovial cells was significantly decreased in the zoledronate group (P<0.05).

Conclusions

Zoledronate decreases the expression of VEGF-A in synovial cells and may affect the development and progression of osteoarthritis.

The SK-N-AS human neuroblastoma cell line develops osteolytic bone metastases with increased angiogenesis and COX-2 expression

Neuroblastoma (NB), which arises from embryonic neural crest cells, is the most common extra-cranial solid tumor of childhood. Approximately half of NB patients manifest bone metastasis accompanied with bone pain, fractures and bone marrow failure, leading to disturbed quality of life and poor survival. To study the mechanism of bone metastasis of NB, we established an animal model in which intracardiac inoculation of the SK-N-AS human NB cells in nude mice developed osteolytic bone metastases with increased osteoclastogenesis. SK-N-AS cells induced the expression of receptor activator of NF-κB ligand and osteoclastogenesis in mouse bone marrow cells in the co-culture. SK-N-AS cells expressed COX-2 mRNA and produced substantial amounts of prostaglandin E₂ (PGE₂). In contrast, the SK-N-DZ and SK-N-FI human NB cells failed to develop bone metastases, induce osteoclastogenesis, express COX-2 mRNA and produce PGE₂. Immunohistochemical examination of SK-N-AS bone metastasis and subcutaneous tumor showed strong expression of COX-2. The selective COX-2 inhibitor NS-398 inhibited PGE₂ production and suppressed bone metastases with reduced osteoclastogenesis. NS-398 also inhibited subcutaneous SK-N-AS tumor development with decreased angiogenesis and vascular endothelial growth factor-A expression. Of interest, metastasis to the adrenal gland, a preferential site for NB development, was also diminished by NS-398. Our results suggest that COX2/PGE₂ axis plays a critical role in the pathophysiology of osteolytic bone metastases and tumor development of the SK-NS-AS human NB. Inhibition of angiogenesis by suppressing COX-2/PGE₂ may be an effective therapeutic approach for children with NB.

Expression levels of vascular endothelial growth factors a and C in patients with peptic ulcers and gastric cancer

Purpose

Vascular endothelial growth factor (VEGF) is one of the most important growth factors for metastatic tumors. To clarify the role of VEGF-A and C in patients with peptic ulcer disease (PUD) or gastric cancer (GC), we evaluated the expression levels of these two molecules. We also analyzed the effect of Helicobacter pylori infection on VEGF-A and C expression levels.

Materials and Methods

Patients with dyspepsia who needed diagnostic endoscopy were selected and divided into three groups: non-ulcer dyspepsia (NUD), PUD, and GC, according to their endoscopic and histopathological results. Fifty-two patients with NUD, 50 with PUD, and 38 with GC were enrolled in this study. H. pylori infection was diagnosed by the rapid urease test. After RNA extraction and synthesis of cDNA, the expression levels of VEGF-A and C were determined by quantitative reverse transcriptase polymerase chain reaction.

Results

The VEGF-C expression level in the PUD and GC groups was significantly higher than that in the NUD group. Moreover, the VEGF-A expression level in the PUD and GC groups was higher than in the NUD group, although the differences were not statistically significant. Significant positive correlations were also observed between the expression levels of these two molecules in the PUD and GC groups. In addition, the expression levels of these two molecules were higher in H. pylori positive patients with PUD or GC than in H. pylori negative patients of the same groups; however, these differences did not reach statistical significance.

Conclusions

Up-regulation of VEGF-C expression during gastric mucosal inflammation may play a role in the development of peptic ulcers or GC.

Microparticles released by vascular endothelial cells increase hypoxia inducible factor expression in human proximal tubular HK-2 cells

Microparticles are produced by vesiculation of the cell plasma membrane and serve as vectors of cell-to-cell communication. Co-culture experiments have shown that hypoxia-inducible factor-α (HIF-α)-regulated-genes are up-regulated in human renal proximal tubular HK-2 cells by endothelial cell factors which might be transported inside endothelial microparticles (EMP). Here we aimed to study in HK-2 cells the effect of EMP, produced by activated endothelial cells, on HIF-α and HIF-α-regulated vascular endothelial growth factor-A (VEGF-A). EMP, at a concentration much lower than that found in plasma, increased the expression of HIF-α/VEGF-A in a COX-2/EP2 receptor dependent manner. Since the EMP/cells ratio was ∼1/1000, we hypothesized that paracrine mediators produced by HK-2 cells amplified the initial signal. This hypothesis was confirmed by two facts which also suggested that the mediators were conveyed by particles released by HK-2 cells: (i) HIF-α was up-regulated in HK-2 cells treated with the pellet obtained from the conditioned medium of the EMP-treated HK-2 cells. (ii) In transwell experiments, EMP-treated cells increased the expression of HIF-α in untreated HK-2 cells. Interestingly, we detected these cells, particles that were released by EMP-treated HK-2 cells. Depending on the pathological context, activation of HIF-α and VEGF-A signaling in renal tissue/cells may have either beneficial or harmful effects. Therefore, our results suggest that their presence in the urinary space of EMP produced by activated endothelial cells may influence the outcome of a number of renal diseases.

MiR-126 regulates the expression of vascular endothelial growth factor A and its downstream target proteins Akt, mTOR and Erk1/2 in gastric cancer cells

AIM: To determine the regulatory effect of miR-126 on expression of vascular endothelial growth factor A (VEGFA)and its downstream proteins including protein kinase B (Akt), mammalian target of rapamycin protein (mTOR) and extracellular regulated protein kinases (Erk1/2) in gastric cancer cells.

METHODS: Recombinant lentivirus LV-miR-126 and miRCURY LNA™ miR-126 inhibitor were used to up-regulate or down-regulate the miR-126 expression in SGC-7901 cells. The cells were divided into a mock group, a lenti-miR-126 group, a lenti-control group, a locked nucleic acid (LNA)-antimiR-126 oligonucleotides group and a LNA-control group. Real-time PCR was used to confirm the relative expression of miR-126, and Western blot was used to detect the expression levels of Akt, mTOR, Erk and VEGFA proteins in different groups.

RESULTS: Western blot analysis demonstrated that the expression of VEGFA and its downstream proteins Akt, mTOR and Erk1/2 was significantly decreased in the lenti-miR-126 group than in the mock group (1.00 ± 0.00 vs 1.60 ± 0.19, 1.00 ± 0.00 vs 1.89 ± 0.23, 1.00 ± 0.00 vs 2.11 ± 0.38, 1.00 ± 0.00 vs 1.52 ± 0.36, all P < 0.01). In contrast, the expression of VEGFA and its downstream proteins Akt, Erk1/2 and mTOR was significantly increased in the LNA-miR-126 group than in the mock group (2.46 ± 0.31 vs 1.60 ± 0.19, 3.09 ± 0.44 vs 1.89 ± 0.23, 3.83 ± 0.64 vs 2.11 ± 0.38, 2.26 ± 0.30 vs 1.52 ± 0.36, all P < 0.01).

CONCLUSION: Our results indicate that miR-126 could regulate the expression of VEGFA and its downstream proteins Akt, Erk1/2 and mTOR. These findings suggest that there may be a miR-126/VEGFA signaling pathway regulating angiogenesis in gastric cancer.

Overexpression of both VEGF-A and VEGF-C in gastric cancer correlates with prognosis, and silencing of both is effective to inhibit cancer growth

BACKGROUND

Vascular endothelial growth factor (VEGF)-A and VEGF-C are two important molecules involving in tumor development and metastasis via angiogenesis and lymphangiogenesis. However, the combined effect of VEGF-A and VEGF-C on the growth of gastric cancer (GC) is not clear.

METHODS

The correlations of VEGF-A and VEGF-C expressions with clinicopathologic parameters and prognosis were evaluated in patients with GC. Furthermore, lentivirus-mediated RNA interfering (RNAi) targeting VEGF-A and/or VEGF-C was employed to silence their expressions in SGC7901 GC cell line. Cell proliferation and apoptosis were measured in vitro. Suppressive effect lentivirus-mediated VEGF-A and/or VEGF-C silencing on GC growth was evaluated in GC bearing mice.

RESULTS

The patients with high expression of both VEGF-A and VEGF-C (A+C+) had larger tumor size, higher peritumoral lymphatic vessel density(P-LVD), microvessel density(MVD), lymphatic vessel invasion (LVI), lymph node(LN) metastasis, and worse prognosis than those with low expression of both VEGF-A and VEGF-C (P<0.05). Lentivirus-mediated RNAi significantly reduced the mRNA and protein expression of VEGF-A and VEGF-C in the SGC7901 cells. The Lenti-miRNA-VEGF-A+VEGF-C significantly inhibited the cell proliferation and tumor growth, compared with Lenti-miRNA-VEGF-A or Lenti-miRNA-VEGF-C (P<0.05). In addition, Lenti-miRNA- VEGF-A+VEGF-C markedly lowered the tumor size in vivo in comparison with Lenti-miRNA-VEGF-A or Lenti-miRNA-VEGF-C (P<0.05).

CONCLUSION

Expressions of both VEGF-A and VEGF-C predict worse prognosis of GC patients. Combined silencing of VEGF-A and VEGF-C markedly suppresses cancer growth than silencing of VEGF-A or VEGF-C. Thus, to inhibit the expressions of VEGF-A and VEGF-C may become a novel strategy for the treatment of GC.

Vascular endothelial growth factor 165b expression in stromal cells and colorectal cancer

AIM: To characterize the implications of vascular endothelial growth factor (VEGF)-A in stromal cells and colorectal cancer and the expression of VEGF-A splice variants.

METHODS: VEGF-A expression in tumor and stromal cells from 165 consecutive patients with colorectal cancer was examined by immunohistochemistry. The association between VEGF-A expression status and clinicopathological factors was investigated. Twenty fresh-frozen samples were obtained for laser capture microdissection to analyze the splice variants of VEGF-A.

RESULTS: VEGF-A was expressed in 53.9% and 42.4% of tumor and stromal cells, respectively. VEGF-A expression in tumor cells (t-VEGF-A) was associated with advanced clinical stage (stage 0, 1/9; stage 1, 2/16; stage 2, 32/55; stage 3, 38/66; stage 4, 16/19, P < 0.0001). VEGF-A expression in stromal cells (s-VEGF-A) increased in the earlier clinical stage (stage 0, 7/9; stage 1, 6/16; stage 2, 33/55; stage 3, 22/66; stage 4, 5/19; P = 0.004). Multivariate analyses for risk factors of recurrence showed that only s-VEGF-A expression was an independent risk factor for recurrence (relative risk 0.309, 95% confidence interval 0.141-0.676, P = 0.0033). The five-year disease-free survival (DFS) rates of t-VEGF-A-positive and -negative cases were 51.4% and 62.9%, respectively. There was no significant difference in t-VEGF-A expression status. The five-year DFS rates of s-VEGF-A-positive and -negative cases were 73.8% and 39.9%, respectively. s-VEGF-A-positive cases had significantly better survival than s-VEGF-A-negative cases (P = 0.0005). Splice variant analysis revealed that t-VEGF-A was mainly composed of VEGF165 and that s-VEGF-A included both VEGF165 and VEGF165b. In cases with no venous invasion (v0), the level of VEGF165b mRNA was significantly higher (v0 204.5 ± 122.7, v1 32.5 ± 36.7, v2 2.1 ± 1.7, P = 0.03). The microvessel density tended to be lower in cases with higher VEGF165b mRNA levels.

CONCLUSION: s-VEGF-A appears be a good prognostic factor for colorectal cancer and includes VEGF165 and VEGF165b.