Refractive Outcomes of 4-Year-old Children after Intravitreal Anti-vascular Endothelial Growth Factor versus Laser Photocoagulation for Retinopathy of Prematurity

Purpose

To compare long-term refractive outcomes associated with intravitreal anti-vascular endothelial growth factor (VEGF) versus laser photocoagulation treatment for retinopathy of prematurity (ROP).

Methods

A total of 52 eyes from 27 ROP patients treated at two tertiary referral-based hospitals from August 2006 to December 2013 were reviewed. The primary outcome was refractive error measured at the age of 4 years, accounting for within-patient inter-eye correlation. Secondary outcomes included the recurrence rate and treatment complications.

Results

The mean age at refraction was 4.7 ± 0.3 years in the laser group (n = 30) and 4.4 ± 0.3 years in the anti-VEGF group (n = 22). No significant differences were noted in gestational age, birthweight, post-menstrual age at treatment, or ROP stage/zone distribution between groups. Mean spherical equivalent was also not significantly different (−1.0 diopters in the laser group and −0.3 diopters in the injection group, p = 0.603). Clustered regression analysis revealed that only gestational age was significantly correlated with mean spherical equivalent (p < 0.001; 95% confidence interval, −0.007 to −0.002). Recurrence was noted in four eyes (13.3%) in the laser group, but this difference was not significant (p = 0.128). There were no major systemic complications reported in either group.

Conclusions

Treatment type, whether laser or anti-VEGF injection, does not appear to influence long-term refractive outcomes in ROP. Concern regarding refractive outcomes should not be the most important factor when selecting ROP treatment modality.

Polydeoxyribonucleotides Improve Diabetic Wound Healing in Mouse Animal Model for Experimental Validation

Background

Wound healing mechanisms is believed to have effects similar to wound healing disorders in diabetic patients, including abnormal inflammatory cells, angiogenesis disorders, and reduced collagen synthesis. Therefore, reestablishment of structural and promoted angiogenesis could be beneficial to promote wound healing process.

Objective

Therefore, we investigated whether the polydeoxyribonucleotide (PDRN) that was self-production in Korea, could be useful as an intradermal injection for promoting wound healing. Also, we validate for wound healing effect of PDRN using healing-impaired (db/db) mice.

Methods

In this study, we confirmed the effects of PDRN by creating wound models in in vitro and in vivo model. Using an in vitro wound healing assay, we observed that PDRN stimulated closure of wounded monolayers of human fibroblast cells. PDRN (8.25 mg/ml) or phosphate-buffered saline (0.9% NaCl) was injected once daily into the dermis adjacent to the wound for 12 days after skin injury.

Results

Time course observations revealed that mice treated with PDRN showed accelerated wound closure and epidermal and dermal regeneration, enhanced angiogenesis. The wound area and depth decreased at 3, 6, 9, and 12 days after skin injury. Histological evaluation showed an increase of vascular endothelial growth factor, CD31, and collagen fibers in the PDRN group compared with the control group, indicating that PDRN was effective in the treatment of delayed wound healing caused by diabetes.

Conclusion

This study suggests that our PDRN has a wound healing effect in transgenic animal models with cells and diabetes through angiogenesis.

Relevance of VEGFA in rat livers subjected to partial hepatectomy under ischemia-reperfusion

Abstract

We examined the effects of VEGFA on damage and regeneration in steatotic and non-steatotic livers of rats submitted to PH under I/R, and characterized the underlying mechanisms involved. Our results indicated that VEGFA levels were decreased in both steatotic and non-steatotic livers after surgery. The administration of VEGFA increased VEGFA levels in non-steatotic livers, reducing the incidence of post-operative complications following surgery through the VEGFR2-Wnt2 pathway, independently of Id1. Unexpectedly, administration of VEGFA notably reduced VEGFA levels in steatotic livers, exacerbating damage and regenerative failure. After exogenous administration of VEGFA in steatotic animals, circulating VEGFA is sequestered by the high circulating levels of sFlt1 released from adipose tissue. Under such conditions, VEGFA cannot reach the steatotic liver to exert its effects. Consequently, the concomitant administration of VEGFA and an antibody against sFlt1 was required to avoid binding of sFlt1 to VEGFA. This was associated with high VEGFA levels in steatotic livers and protection against damage and regenerative failure, plus improvement in the survival rate via up-regulation of PI3K/Akt independently of the Id1-Wnt2 pathway. The current study highlights the different effects and signaling pathways of VEGFA in liver surgery requiring PH and I/R based in the presence of steatosis.

Key messages

VEGFA administration improves PH+I/R injury only in non-steatotic livers of Ln animals.

VEGFA benefits are exerted through the VEGFR2-Wnt2 pathway in non-steatotic livers.

In Ob rats, exogenous VEGFA is sequestered by circulating sFlt1, exacerbating liver damage.

Therapeutic combination of VEGFA and anti-sFlt1 is required to protect steatotic livers.

VEGFA+anti-sFlt1 treatment protects steatotic livers through a VEGFR2-PI3K/Akt pathway.

Electronic supplementary material

The online version of this article (10.1007/s00109-019-01811-y) contains supplementary material, which is available to authorized users.

[The protective effect of pigment epithelial-derived factor modified human umbilical cord mesenchymal stem cells on rats with diabetic retinopathy]

Objective: To investigate the effect of pigment epithelial-derived factor (PEDF) gene-modified human umbilical cord mesenchymal stem cells (MSC) on rats with diabetic retinopathy (DR). Methods: Experimental study. Human umbilical cord MSC were transfected by lentivirus packaging PEDF-MSC-green fluorescent protein (GFP) and GFP-MSC plasmid vectors, and the expression of PEDF and vascular endothelial growth factor (VEGF) was measured in the cell culture medium. Fifty adult male Sprague-Dawley rats were randomly divided into five groups: normal control group (group A), DR control group (group B), phosphate-buffered saline (PBS) treated group (group C), GFP-MSC treated group (group D) and PEDF-MSC-GFP treated group (group E), with 10 rats in each group. Streptozotocin was intraperitoneally injected to make early DR models. After four-month intervention, groups D and E were given intravitreal injection of GFP-MSC and PEDF-MSC-GFP; group C was given intravitreal injection of phosphate-buffered saline; groups A and B did not receive special treatment. The changes of retina in different groups were detected by hematoxylin and eosin staining, and the thickness of inner plexiform layer, inner nuclear layer and outer nuclear layer was measured by computer-based image analytical system. Immunohistochemistry was applied to observe PEDF and VEGF. Real-time quantitative polymerase chain reaction was used to detect the expression of PEDF and VEGF mRNA. Results: The expression of CD105, CD73 and CD90 was positive, while the expression of CD34, CD45, CD11b, CD19 and HLA-DR was negative. ELISA results showed that after transfection PEDF protein expression in the supernatant of PEDF-MSC (84.09±7.07) μg/L was higher than the control group (9.03±0.14) μg/L (P<0.05). At 2 weeks after intravitreal injection, green fluorescence was observed in the rat vitreous of groups D and E under a fluorescence microscope; no obvious green fluorescence was found in the retina. After 2 months of intravitreal injection, the thickness of inner plexiform layer in group E was significantly decreased; the thickness of inner nuclear layer and outer nuclear layer was higher (P<0.05). Immunohistochemical staining showed that 2 months after intravitreal treatment, the average optical density values of PEDF were improved, but the average optical density values of VEGF were decreased in group E (P<0.05). Real-time polymerase chain reaction showed that 2 months after treatment, the expression level of PEDF mRNA in group E was improved, but the expression level of VEGF mRNA was decreased (P<0.05). Conclusions: Intravitreal injection of PEDF-MSC could up-regulate the expression of PEDF and down-regulate the expression of VEGF in diabetic rats and may represent a novel candidate resource for cell therapy of DR nerve damage. (Chin J Ophthalmol, 2017, 53, 540-547).

[Vascular endothelial growth factor is up-regulated by leukemia inhibitory factor and interleukin-6 in human endometriotic stromal cells]

Objective: To compare the expression of leukemia inhibitory factor (LIF), interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) in tissue and fluid samples from patients with endometriosis, and investigate whether LIF and IL-6 regulate VEGF in human endometriotic stromal cells (ESC). Methods: The levels of VEGF, LIF, IL-6 in serum, peritoneal fluid of patients with and without endometriosis were measured by ELISA. The mRNA of these three factors in the ectopic and eutopic endometrial tissue and stromal cells were measured by real-time PCR. ESC derived from ovarian endometriomas were cultured using the method of primary cell culture with LIF and IL-6, and the level of VEGF mRNA and protein were measured by the method of real-time PCR and ELISA respectively. Results: VEGF and IL-6 concentration were 1.2 and 1.3 times higher in the serum of patients with endometriosis than in the control group [(94±19) versus (78±17) ng/L; (45±14) versus (35±9) ng/L; all P<0.05]. VEGF and IL-6 concentration were 1.2 and 1.4 times higher in the peritoneal fluid of patients with endometriosis than in the control group [(110±25) versus (91±21) ng/L; (69±20) versus (49±15) ng/L; all P<0.05]. VEGF and IL-6 concentrations in peritoneal fluid of patients with endometriosis were 1.2 and 1.5 times higher than in serum (all P<0.01). VEGF, LIF and IL-6 mRNA expression were 2.2, 8.6, 44.7 times higher in ESC compared with the matching eutopic endometrial stromal cells (all P<0.01). LIF and IL-6 mRNA were 2.0 and 64.8 times higher in ectopic endometrial tissue than the matching eutopic endometrial tissue (all P<0.05).ESC cultured with LIF, IL-6 and LIF+IL-6 induce VEGF protein secretion [(106±18), (124±30), (140±27) ng/L] by 1.3, 1.5 and 1.7 times (all P<0.05). Conclusion: Overexpression of LIF and IL-6 may synergistically contribute to upregulation of VEGF in ESC and promote development of endometriosis.

[Treatment of retinopathy of incontinentia pigmenti by anti-vascular endothelial growth factor]

Objective: To investigate the treatment of retinopathy of incontinentia pigmenti by anti-vascular endothelial growth factor. Methods: Retrospective study of 5 patients(8 eyes) diagnosed retinopathy of incontinentia pigmenti from 2005 to 2017, including 0 males and 5 females (8 eyes involved) with an average age of 2.4 months(range, 1-5 months). Medical history and family history were recorded in detail for all children. We did the examination of anterior segment of the eyeball, vitreous body,fundus and intraocular pressure for the 5 patients(8eyes).What's more,wo also took pictures for fundus with the machine of Retcam. Fundus fluorescence angiography (FFA) was performed in 2 patients(4 eyes). Different surgical methods were selected according to the specific conditions of the eye and postoperative were observed. Results: At the time of initial diagnosis, preretinal hemorrhage did not affect the macular region in 3 cases (5 eyes), pre retinal hemorrhage affected the macular region in 1 case(1 eye), the retinal neovascularization in 3 cases(5 eyes), the retinal detachment in 2 cases(2 eyes), and nonvascular zone of peripheral retinal in 5cases(8 eyes). Treatment and drug selection: 3 cases(5 eyes) were treated with injection anti-VEGF drug into vitreous body cavity, 1 case(1 eye) was treated with injection anti-VEGF drug into vitreous body cavity plus laser photocoagulation, 1 case(1 eye) was treated with anti-VEGF drugs plus vitrectomy. 1 case(1 eye) was treated with anti-VEGF drugs plus retinal cryotherapy and sclera bucking. In patients of injection anti-VEGF drug into vitreous body cavity, 2 cases(3 eyes) were given a single dose and 1 case (2 eyes) was given a repeated dose. Drug selection: 4 cases(6 eyes) ranibizumab injection (injection dose 0.025 ml), 1 case (2 eyes)conbercept injection (injection dose 0.025 ml). To follow-up date, etina was flat in 4 patients (7 eyes), epiretinal membrane in 2 patients(2 eyes), retinal detachment in 1 patient(1 eye). Conclusions: The efficacy of anti-vascular endothelial growth factor in the treatment of retinopathy of incontinentia pigmenti was prelininarily confimed.However,the optimal use timing,dosage,local and systemic safety issues were needed to be further studied. (Chin J Ophthalmol, 2019, 55:294-301).

[Be cautious to treat retinopathy of prematurity with anti-vascular endothelial growth factor pharmacotherapy]

With the rapid development of perinatology in China and the implementation of the two-child policy, the survival rate of premature and low weight infants is obviously improved, and the incidence of retinopathy of prematurity (ROP) in preterm infants has been increasing year by year. ROP can lead to blindness when it is serious. It is the first cause of blindness of children in our country, and it is a heavy burden on family and society. With novel insights in the pathogenesis of the disease, anti-vascular endothelial growth factor pharmacotherapy has blated its way into ophthalmological practice and significantly changed the management of ROP. However, facing such promising drugs, we still need to take caution with the safety and long-time efficacy, investigate more reasonable dosing schedules and study the follow-up time. (Chin J Ophthalmol, 2019, 55: 246-249).

PD-L1 protein expression in non-small-cell lung cancer and its relationship with the hypoxia-related signaling pathways: A study based on immunohistochemistry and RNA sequencing data

OBJECTIVES

Therapies that target programmed cell death protein-1 (PD-1)/programmed death-ligand 1 (PD-L1) have shown promising efficacy in non-small-cell lung cancer (NSCLC). Hypoxia-related genes are also important regulators of PD-L1, and the role of PD-L1 in NSCLC is still not clear. The objective of this study was to investigate PD-L1 expression and its correlation with hypoxic-inducible factor 1α (HIF1A), vascular endothelial growth factor A (VEGFA), glucose transporter 1 (GLUT1), and carbonic anhydrase 9 (CAIX) expression in NSCLC patients. The association between PD-L1 expression and survival was also determined.

MATERIALS AND METHODS

PD-L1/protein expression was evaluated in 295 resected NSCLCs and its correlation with HIF1A, VEGFA, GLUT1, CAIX expression and survival was determined based on immunohistochemical and RNA sequencing data obtained from The Cancer Genome Atlas (TCGA) database.

RESULTS

PD-L1 protein expression was significantly correlated with HIF1A, VEGFA, GLUT1, and CAIX expression only in adenocarcinoma when a 10% or a 50% cut-off was used. PD-L1 mRNA expression was also significantly correlated with HIF1A, VEGFA, GLUT1, and CAIX expression in adenocarcinoma. Univariate analysis revealed that HIF1A expression was associated with poor recurrence-free survival (RFS), and GLUT1 was associated with poor overall survival (OS) and RFS. GLUT1 was an independent prognostic factor for OS in multivariate analysis of immunohistochemical and TCGA data (p = 0.024 and 0.029, respectively). Patients with low expression of both PD-L1 and GLUT1 had longer OS than other patterns in immunohistochemical and TCGA data (p = 0.003 and 0.051, respectively).

CONCLUSIONS

PD-L1 protein and mRNA expression were correlated with HIF1A, VEGFA, GLUT1, and CAIX expression in adenocarcinoma alone. Low expression of GLUT1 and low expression of both PD-L1 and GLUT1 were associated with improved prognosis. Our findings support the rationale for co-targeting hypoxia-related genes and PD-L1 in cancer therapy. Expression of hypoxia-related genes may be helpful in selecting patients appropriate for PD-L1 therapy.

Intravitreal Ranibizumab Therapy for Diabetic Macular Edema in Routine Practice: Two-Year Real-Life Data from a Non-interventional, Multicenter Study in Germany

INTRODUCTION

The prospective, non-interventional OCEAN study examined the use of intravitreal ranibizumab injections for the treatment of diabetic macular oedema (DME) in a real-world setting in Germany.

METHODS

Adults with DME receiving ≥ 1 ranibizumab (0.5 mg) injections were recruited by 250 ophthalmologists. Best-corrected visual acuity (VA) testing, imaging and treatments were performed according to the investigators' routine practice and documented over 24 months.

RESULTS

The full analysis set included 1226 participants. Mean baseline VA was 60.6 [95% CI: 59.7; 61.5] Early Treatment Diabetic Retinopathy Study letters. VA improved by ≥ 15 letters in 21.5% and 23.5% of the participants at 12 months and 24 months, respectively. They received a mean number of 4.42 [95% CI: 4.30; 4.54] injections in the first year and 5.52 [95% CI: 5.32; 5.73] injections over 24 months, which was markedly lower than in clinical trials. Only 33.4% of the participants received an upload with four initial monthly injections as recommended by the German ophthalmologic societies. Time-to-event analyses that account for missing data inherent to a non-interventional study design demonstrated that participants receiving ≥ 7 injections in the first year had a faster response, but the duration of the response was shorter compared to the subgroups receiving 1-3 and 4-6 injections. Serious adverse events were reported for 143/1250 (11.4%) participants in the safety population.

CONCLUSION

Under-treatment is a major problem of DME anti- vascular endothelial growth factor therapy under real life conditions. Despite fewer injections given compared to randomised controlled trials with a consequently reduced overall mean visual gain, a profound functional improvement (≥ 15 letters) was achieved over 2 years in 23.5% of eyes with DME.

TRIAL REGISTRATION NUMBER

NCT02194803, ClinicalTrials.gov.

FUNDING

Novartis Pharma GmbH, Nuremberg, Germany.

VEGF-A is associated with early degenerative changes in cartilage and subchondral bone

Paired cartilage and subchondral bone of subjects with no clinical history of joint disorders were analyzed to determine whether antioxidant enzymes, inflammatory cytokines and growth factors can be linked to a pre-osteoarthritis. Tissue explants were phenotyped according to Osteoarthritis Research Society International grading and micro-computed tomography, and also screened for the expression of several markers using quantitative polymerase chain reaction. The expression of these same genes was measured in SW1353 cells treated with hydrogen peroxide, to gain insight into the pathways involved with oxidative stress responses. Vascular endothelial growth factor A (VEGF-A) was up-regulated in the cartilage samples that showed early cartilage or bone degeneration. Oxidative stress in chondrocytes provoked up-regulation of interleukin-1β, interleukin-6, aggrecan, and SRY-box containing gene 9. Our results confirm the hitherto evidence of the deteriorating effects of the oxidative stress on cartilage and suggest the link between VEGF-A and pre-osteoarthritis.

Dll4-Notch1 signaling but not VEGF-A is essential for hyperoxia induced vessel regression in retina

It is well recognized that decreased vascular endothelial growth factor A (VEGF-A) mRNA plays an important role in retinal vessel regression induced by hyperoxia. However, this concept has been challenged by increasing new evidence. Furthermore, VEGF-A strongly enhances Dll4 expression and inhibition of Dll4-Notch signaling leads to excessive sprouting angiogenesis. Recently, it is shown that inactivation of Dll4-Notch1 signaling reduce hyperoxia induced vessel regression. It is unknown whether sprouting angiogenesis contributes to the protective effect or not and further investigations are needed. Moreover, the expression of Dll4 or Notch1 activation in the regressing plexus remains elucidated. To determine the role of VEGF-A and Dll4-Notch1 signaling in hyperoxia induced vascular regression in the retina, we used mice at postnatal day 5 (P5) - P7. Hyperoxia induced massive vascular regression in the central plexus but not in the angiogenic plexus and had no effect on sprouting angiogenesis. Immunostaining showed that VEGF-A was significantly repressed in the angiogenic front region after hyperoxia exposure but not detectable in the central area of both normoxia and hyperoxia treated retinas. In contrast, Notch ligand Delta-like 4 (Dll4) and Notch1 intracellular domain (N1-ICD) expression were inhibited in the regressing capillaries of central retina but comparable in the angiogenic plexus after high oxygen treatment. Moreover, administration of Dll4 neutralizing antibody or γ-Secretase inhibitor DAPT significantly aggravated vessel regression induced by short-time hyperoxia administration. Our data show that repressed Dll4-Notch1 signaling pathway but not downregulation of VEGF-A expression are responsible for hyperoxia induced pervasive vessel regression.

[The genetic factors of non-response to anti-vascular endothelial growth factor therapy]

The response to anti-vascular endothelial growth factor (VEGF) treatment is variable. It is generally measured in terms of changes in correlated functional and/or anatomical outcomes, and patients are then classified as optimal response, poor response and non-response. The precise cause of non-response remains undetermined. A variety of factors could account for poor or non-response to anti-VEGF therapy, such as age, baseline vision, disease course, lesion characteristics and genomic polymorphism. At the present time, many studies on the genetic factors of non-response or poor response to anti-VEGF treatment mainly focus on VEGF genes (VEGF-A, VEGFR-2), complement factor H (CFH), age-related maculopathy susceptibility 2 (LOC387715/ARMS2), high temperature factor A-1 (HTRA1), interleukin-related gene (IL-8 rs4073) and so forth. It is still worthy of further investigations that how to assess genetic reasons for non-response or poor response, so that we can provide individualized treatment sequences and predict the response to anti-VEGF therapy. (Chin J Ophthalmol, 2018, 54:873-878).

The protective effect of low-energy shock wave on testicular ischemia-reperfusion injury is mediated by the PI3K/AKT/NRF2 pathway

AIMS

Testicular ischemia-reperfusion (IR) injury is the primary pathophysiological consequence of testicular torsion. Low-energy shock wave (LESW) is an effective treatment for certain diseases. The present study investigated whether LESW could improve on testicular IR injury in rats and examined the involved mechanism.

MAIN METHODS

Testicular reperfusion was induced in rats after 1-h ischemia. The first LESW treatment was performed 30 min prior to testicular reperfusion, and then every other day for another 3 applications. LY294002 was applied to investigate the involved mechanism. Testicular morphological changes and malonaldehyde (MDA) level were respectively assessed by hematoxylin-eosin staining. Western blot and thiobarbituric acid method. Western blot, real-time quantitative PCR and immunohistochemistry were performed to assess the apoptosis, the activation of phosphatidylinositol-4,5-bisphosphate 3-kinase/protein kinase B (PI3K/AKT) pathway the nuclear factor erythroid 2-related factor 2 (NRF2) and vascular endothelial growth factor A (VEGF-A) level in the testis of rats.

KEY FINDINGS

LESW improved testicular IR injury in rats. Moreover, LESW upregulated the phosphorylation levels of AKT and glycogen synthase kinase 3β (GSK-3β). Also, it upregulated the levels of nuclear NRF2, heme oxygenase 1 (HO-1) and NAD(P)H quinone dehydrogenase 1 (NQO-1) in these rats. Nevertheless, LY294002 blocked these protective effects. LESW also upregulated VEGF-A level in rats with testicular IR injury.

SIGNIFICANCE

This study demonstrated that LESW could ameliorate testicular IR injury in rats, which might be attributed to the activation of PI3K/AKT/NRF2 pathway. These findings suggested the potential of LESW in the treatment of testicular torsion.

Fatty acid binding protein 5 promotes tumor angiogenesis and activates the IL6/STAT3/VEGFA pathway in hepatocellular carcinoma

BACKGROUND

Tumor angiogenesis is an essential process for facilitating tumor growth and metastasis. Fatty acid binding protein 5(FABP5)is highly expressed in hepatocellular carcinoma (HCC). Thus, we investigated the role of FABP5 in tumor angiogenesis during HCC development.

METHODS

In this study, the protein and mRNA levels of FABP5 in matched HCC and adjacent noncancerous liver tissues from 43 patients were determined using immunohistochemistry and real-time quantitative PCR, respectively. Two HCC cell lines (Huh7 and SMMC-7721) and human umbilical vein endothelial cells (HUVECS) were used to investigate the pro-angiogenic effect of FABP5 by tube formation, CCK8 and Transwell migration assays. The expression levels of interleukin 6 (IL6) and vascular endothelial growth factor A (VEGFA) secreted from HCC cells were detected by enzyme-linked immunosorbent assay (ELISA).

RESULTS

In 43 HCC patients, the expression of FABP5 mRNA was positively correlated with intratumoral VEGFA mRNA expression. FABP5 mRNA expression was also associated with adverse HCC characteristics. In vitro, cell viability, cell migration and tube formation in HUVECs were enhanced with increasing expression of FABP5 in HCC cells. Downregulation of FABP5 expression inhibited the IL6/STAT3/VEGFA pathway in HCC cells and inhibited tumor angiogenesis.

CONCLUSION

FABP5 was shown to promote angiogenesis and activate the IL6/STAT3/VEGFA pathway in HCC. FABP5 may be a potential antiangiogenic target in the treatment of HCC.

Cyclic stretch induces VEGFA alternative splicing via Serine/Arginine-Rich Splicing Factor 1

Abnormal proliferation of vascular smooth muscle cells (VSMCs) induced by high cyclic stretch is crucial in the vascular remodeling during hypertension. Vascular endothelial growth factor A (VEGFA) alternative splicing plays important roles in the pathological process of vascular diseases and remodeling. However, the roles of VEGFA isoforms in modulating VSMC functions in response to cyclic stretch remain unclear. We hypothesize that high cyclic stretch may induce VEGFA alternative splicing via Serine/arginine-rich splicing factor 1 (SRSF1) which subsequently induce VSMC proliferation. In the present research, hypertensive rat model was established using the abdominal aortic constriction method. In comparison with sham-operated group, immunohistology staining showed translocation of SRSF1 into nuclei in hypertensive rat thoracic aorta, and RT-PCR detected a shift of VEGFA expression pattern, including the increased expression of VEGFA120 and VEGFA164, but not VEGFA188.Then VSMCs were subjected to cyclic stretch in vitro using a Flexercell strain unit. VEGFA ELISA assay showed 15% cyclic stretch increased the secretion of VEGFA which significantly increased proliferation of VSMCs. Western blot and immunofluorescence detected accumulation of SRSF1 in nuclei after 15% cyclic stretch application. Furthermore, SRSF1-specific siRNA transfection reversed the VEGFA secretion induced by pathological high cyclic stretch. Our present results suggested that pathologically high cyclic stretch induces the shuttling of SRSF1 which results in the secretive pattern splicing of VEGFA and finally contributes to the proliferation of VSMCs.

Overexpression of STAT1 suppresses angiogenesis under hypoxia by regulating VEGF‑A in human glioma cells

Hypoxia is common in Glioblastoma (GBM). By regulating the 'hypoxia signaling cascade', hypoxia affects several processes including cell proliferation, invasion, and angiogenesis. Some studies have revealed that signal transducer and activator of transcription (STAT), including STAT1, is abnormal under hypoxia in several cancers. Here, we investigated the role of STAT1 under hypoxia in glioma progression. We found that STAT1 was downregulated under a hypoxic condition in U251 and U373. STAT1 overexpression can not only decrease proliferation, migration and invasion in U251 and U373 but also inhibit tube formation of HBMECs. Moreover, overexpression of STAT1 decreased tumor growth and prolonged the overall survival of xenograft mice. We also showed that STAT1 overexpression inhibited the expression of HIF-1α and VEGF-A. Our work suggests that STAT1 plays a pivotal role as a tumor suppressor in glioma under hypoxia, and it could be a potential new therapeutic target in glioma.

Long noncoding RNA H19 upregulates vascular endothelial growth factor A to enhance mesenchymal stem cells survival and angiogenic capacity by inhibiting miR-199a-5p

Background

Currently, the overall therapeutic efficiency of mesenchymal stem cells (MSCs) transplantation for the treatment of cardiovascular disease is not satisfactory. The low viability and angiogenic capacity of the implanted cells in the local infarct tissues restrict their further application. Evidence shows that long noncoding RNA H19 (lncRNA-H19) mediates cell survival and angiogenesis. Additionally, it is also involved in MSCs biological activities. This study aimed to explore the functional role of lncRNA-H19 in MSCs survival and angiogenic capacity as well as the underlying mechanism.

Methods

MSCs were obtained from C57BL/6 mice and cultured in vitro. Cells at the third passage were divided into the following groups: MSCs+H19, MSCs+H19 NC, MSCs+si-H19, MSCs+si-H19 NC and MSCs. The MSCs+H19 and MSCs+H19 NC groups were transfected with lncRNA-H19 and lncRNA-H19 scramble RNA respectively. The MSCs+si-H19 and MSCs+si-H19 NC groups were transfected with lncRNA-H19 siRNA and lncRNA-H19 siRNA scramble respectively. MSCs were used as the blank control. All groups were exposed to normoxia (20% O₂) and hypoxia (1% O₂)/serum deprivation (H/SD) conditions for 24 h. Cell proliferation, apoptosis and vascular densities were assessed. Bioinformatics and dual luciferase reporter assay were performed. Relevant biomarkers were detected in different experimental groups.

Results

Overexpression of lncRNA-H19 improved survival and angiogenic capacity of MSCs under both normoxia and H/SD conditions, whereas its knockdown impaired cell viability and their angiogenic potential. MicroRNA-199a-5p (miR-199a-5p) targeted and downregulated vascular endothelial growth factor A (VEGFA). MiR-199a-5p was a target of lncRNA-H19. LncRNA-H19 transfection led to a decreased level of miR-199a-5p, accompanied with an elevated expression of VEGFA. However, both miR-199a-5p and VEGFA presented inverse alterations in the condition of lncRNA-H19 knockdown.

Conclusions

LncRNA-H19 enhanced MSCs survival and their angiogenic potential in vitro. It could directly upregulate VEGFA expression by inhibiting miR-199a-5p as a competing endogenous RNA. This mechanism contributes to a better understanding of MSCs biological activities and provides new insights for cell therapy based on MSCs transplantation.

[Tumor-secreted vascular endothelial growth factor A increases the pulmonary metastasis from nasopharyngeal carcinoma]

Objective: Vascular endothelial growth factor A (VEGFA) was investigated as the key protein which might promote the specific metastasis progress of nasopharyngeal carcinoma. Methods: Sixteen specimens of pulmonary metastasis carcinoma and counterparts in primary nasopharyngeal carcinoma tissue were collected from patients. The expression of VEGFA through immunohistochemistry was investigated.VEGFA was knocked down by siRNA in two cell lines of nasopharyngeal carcinoma (CNE-1 and 5-8F), MTT and Transwell test were used to explore the role of VEGFA in praxiology. Then shRNA was used to cultivate the stable CNE-1 cell line with down-regulated-expression of VEGFA. The nude mice models were built through tail vein injection of specific nasopharyngeal carcinoma cells, and lungs were collected to perform further metastasis analysis. Results: Previous genetic studies showed that VEGFA had higher expression in metastasis tissue, and the result was validated in the present study using immunohistochemistry. The percentage of positive cells was 84.8% in pulmonary metastasis group, 51.5% in primary tissue group (t=8.639, P<0.05), average optical density was 0.154 in pulmonary metastasis group, 0.061 in primary tissue group (t=18.791, P<0.05). Low expression of VEGFA inhibited cell viability of optical density value of CNE-1 in siRNA gourp was 0.715, 0.902 in control group (t=7.274, P<0.05); 5-8F in siRNA group was 0.715, 0.935 in control group (t=7.751, P<0.05). Number counting suppressed migration of CNE-1 in siRNA group was 52 per high-power lens, 124 per high-power lens in control group (t=29.380, P<0.05), 5-8F in siRNA group was 65 per high-power lens, 155 per high-power lens in control group (t=18.181, P<0.05). Number counting invasion of CNE-1 in siRNA gourp was 38 per high-power lens, 86 per high-power lens in control group (t=27.665, P<0.05), 5-8F in siRNA group was 52 per high-power lens, 116 per high-power lens in control group (t=40.972, P<0.05) in vitro. Furthermore, knock-down of VEGFA in nasopharyngeal carcinoma reduced the pulmonary metastasis in vivo. Number counting of tumor volumes in shRNA group was 2.4, and 11.0 in control group (t=6.143, P<0.05); average optical density of immunohistochemistry in shRNA group was 0.033, and 0.176 in control group (t=15.734, P<0.05). Conclusions: Results above reveal the overexpression of VEGFA in nasopharyngeal carcinoma can facilitate the pulmonary metastasis. Targeting VEGFA may provide a new biomarker of clinical study.

Clinical Significance of VEGF-A and Microvessel Density in Diffuse Large B-Cell Lymphoma and Low-Grade Follicular Lymphoma

Angiogenesis is essential for the development, growth and progression of tumors. Although vascular endothelial growth factor (VEGF) is a well-known proangiogenic factor, its impact on lymphoma has not yet been fully clarified. The aim of this study was to evaluate VEGF-A -expression and microvessel density (MVD) in aggressive lymphoma such as diffuse large B-cell lymphoma (DLBCL), in indolent lymphomas such as low-grade follicular lymphoma (FL), and in lymph node reactive follicular hyperplasia (FH). In 80 prospective and retrospective cases (30 DLBCL, 30 FL and 20 FH), CD31 was analyzed by immunohistochemical staining assessing density of blood vessels, as well as the total number of CD31 positive endothelial cells. The results were compared with relevant clinical data. MVD was 85% in FH, followed by 60% in DLBCL and 43% in low-grade FL. VEGF-A was significantly higher in DLBCL than in low-grade FL and FH. A statistically significant association of MVD and VEGF-A with the International Prognostic Index (IPI) was found in DLBCL. High MVD and VEGF-A expression was observed in DLBCL patients with high IPI, while there was no statistically significant association between MVD and VEGF-A with the Follicular Lymphoma International Prognostic Index in low-grade FL. Our results suggested an important relationship between angiogenesis and high-grade lymphoma.

Midkine Controls Arteriogenesis by Regulating the Bioavailability of Vascular Endothelial Growth Factor A and the Expression of Nitric Oxide Synthase 1 and 3

Midkine is a pleiotropic factor, which is involved in angiogenesis. However, its mode of action in this process is still ill defined. The function of midkine in arteriogenesis, the growth of natural bypasses from pre-existing collateral arteries, compensating for the loss of an occluded artery has never been investigated. Arteriogenesis is an inflammatory process, which relies on the proliferation of endothelial cells and smooth muscle cells. We show that midkine deficiency strikingly interferes with the proliferation of endothelial cells in arteriogenesis, thereby interfering with the process of collateral artery growth. We identified midkine to be responsible for increased plasma levels of vascular endothelial growth factor A (VEGFA), necessary and sufficient to promote endothelial cell proliferation in growing collaterals. Mechanistically, we demonstrate that leukocyte domiciled midkine mediates increased plasma levels of VEGFA relevant for upregulation of endothelial nitric oxide synthase 1 and 3, necessary for proper endothelial cell proliferation, and that non-leukocyte domiciled midkine additionally improves vasodilation.

The data provided on the role of midkine in endothelial proliferation are likely to be relevant for both, the process of arteriogenesis and angiogenesis. Moreover, our data might help to estimate the therapeutic effect of clinically applied VEGFA in patients with vascular occlusive diseases.

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Leukocyte domiciled midkine is decisive for collateral endothelial cell proliferation in arteriogenesis.

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Midkine controls the bioavailability of VEGFA mediating endothelial Nos1 and Nos3 expression.

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Nos1 and Nos3, relevant for endothelial cell proliferation, can substitute for each other.

Arteriogenesis is a life and tissue saving process as it compensates for the loss of an occluded artery. Decoding the underlying molecular mechanisms is a prerequisite for the development of novel therapeutic options to treat patients with vascular occlusive diseases. Lautz et al. identified midkine to be responsible for the increased bioavailability of VEGFA during arteriogenesis, necessary and sufficient to promote endothelial cell proliferation. These data might help to estimate the therapeutic effect of clinically applied VEGFA. As the identified mechanisms might also apply for angiogenesis, they are likely to be of broader relevance, e.g. in terms of tumor treatment.

Retinal Nerve Fiber Layer Thickness in Glaucoma Patients Treated with Multiple Intravitreal Anti-Vegf (Bevacizumab) Injections

Over the past decade, intravitreal injections of anti-VEGF agents have been widely used and intensively developed as a treatment option for many ophthalmological indications. Due to its availability and low cost, the most frequently used anti-VEGF agent is bevacizumab. This type of therapy is often indicated in patients with exudative age-related macular degeneration (ARMD) and diabetic macular edema (DME). If, in addition to these two conditions, patients have a diagnosis of primary open angle glaucoma (POAG), they also present with optic nerve head (ONH) retinal nerve fiber layer (RNFL) thinning. The aim of this prospective study was to establish whether administering bevacizumab to patients with POAG leads to additional reduction of RNFL thickness. The study included 60 patients divided into two groups. First group comprised the eyes of patients with exudative ARMD and POAG, whereas second group comprised the eyes of patients with DME and POAG, all treated with bevacizumab. Control group comprised the fellow eye of each involved patient, which was not treated with bevacizumab. In a period of one year, all patients underwent optical coherence tomography (OCT) measurements of ONH RNFL thickness. The results of all patients were compared between the two study groups and then with control group results. Study results showed a decrease of RNFL in both groups of patients. Comparison of these two groups of patients after one year revealed a statistically more significant decrease in RNFL thickness in the second group (DME + POAG).

Sustained-released mixture of vascular endothelial growth factor 165 and fibrin glue strengthens healing of ileal anastomoses in a rabbit model with intraperitoneal infection

Purpose

To investigate the effects of a sustained-released mixture of vascular endothelial growth factor 165 (VEGF165) and fibrin glue (FG) local administration on postoperative rabbit ileal anastomoses.

Methods

One hundred twenty-eight male and female New Zealand white rabbits underwent intraperitoneal infection subsequent ileal anastomosis surgery were divided randomly into 4 groups, including 32 animals in each, applied with saline solution, FG, rhVEGF165 and a mixture of rhVEGF165 with FG (VEGF + FG) on the anastomoses, respectively. The incidences of anastomotic leakage were observed. Histopathological examination for inflammatory infiltration, fibroblast proliferation, and capillary vascular proliferation were performed. Then, bursting pressure and hydroxyproline concentrations were assessed in anastomoses sits on postoperative days 3, 5, 7, and 14.

Results

Rabbits in VEGF + FG group had the lowest incidence of leakage (P < 0.05). Histological evaluations revealed that granulation tissue was formed on days 5 after anastomosis; fibroblast proliferation and capillary vascular proliferation were significantly increased on days 7 and 14 in VEGF + FG group. Furthermore, there was a statistically significant difference in the mean bursting pressures between VEGF + FG group and other groups on days 7 and 14 (P < 0.05), and rabbits in VEGF + FG group exhibited a higher concentration than VEGF group (P < 0.05) and FG group (P < 0.05) on day 14.

Conclusion

Administration of VEGF165 mixed with FG to ileal anastomosis accelerates wound healing and enhances the anastomosis by increased angiogenesis.

Effects of miRNA-200b on the development of diabetic retinopathy by targeting VEGFA gene

The present study explored the effect of miR-200b on the development of diabetic retinopathy (DR) by targeting vascular endothelial growth factor A (VEGFA) gene. The study populations consisted of 255 DR patients (case group) and 253 healthy people (control group), while the expressions of miR-200b and VEGFA mRNA were detected by quantitative real-time PCR (qRT-PCR). Bioinformatics software and dual-luciferase reporter assay were used to confirm VEGFA as a target gene of miR-200b Also, a total of 70 Wistar male rats were selected and randomly assigned into blank, normal control (NC), miR-200b mimics, miR-200b inhibitors, miR-200b inhibitors + silencing vascular endothelial growth factor A (siVEGFA), and siVEGFA groups (n=10/group) respectively. Streptozotocin (STZ)-induced rat models of DR were successfully established. VEGFA, transforming growth factor-β1 (TGF-β1), hepatocyte growth factor (HGF), and pigment epithelium-derived factor (PEDF) were detected using qRT-PCR and Western blotting. In comparison with the control group, the case group showed lower expression of miR-200b but higher expression of VEGFA mRNA. VEGFA was confirmed as a target gene of miR-200b Rats in the miR-200b mimics and siVEGFA groups exhibited higher expression of PEDF mRNA and protein but lower expressions of VEGFA, TGF-β1, HGF protein, and mRNA than the NC group. There was no remarkable difference in expressions of PEDF, VEGFA, TGF-β1, HGF protein, and mRNA between the miR-200b inhibitors + siVEGFA and NC groups. In conclusion, the present study demonstrated that miR-200b might alleviate DR development by down-regulating its target gene VEGFA.

Gastric Cancer and Angiogenesis: Is VEGF a Useful Biomarker to Assess Progression and Remission?

Gastric cancer (GC) has high mortality owing to its aggressive nature. Tumor angiogenesis plays an essential role in the growth, invasion, and metastatic spread of GC. The aim of this work was to review the angiogenic biomarkers related to the behavior of GC, documented in the literature. A search of the PubMed database was conducted with the MeSH terms: “Stomach neoplasms/blood [MeSH] or stomach neoplasms/blood supply [MeSH] and angiogenic proteins/blood [Major]”. A total of 30 articles were initially collected, and 4 were subsequently excluded. Among the 26 articles collected, 16 examined the role of vascular endothelial growth factor (VEGF), 4 studied endostatin, 3 investigated angiopoietin (Ang)-2, 2 studied the Ang-like protein 2 (ANGTPL2), and 1 each examined interleukin (IL)-12, IL-8, and hypoxia inducible factor. Regarding VEGF, 6 articles concluded that the protein was related to lymph node metastasis or distant metastases. Five articles concluded that VEGF levels were elevated in the presence of GC and decreased following tumor regression, suggesting that VEGF levels could be a predictor of recurrence. Four articles concluded that high VEGF levels were correlated with poor prognosis and lower survival rates. Ang-2 and ANGTPL2 were elevated in GC and associated with more aggressive disease. Endostatin was associated with intestinal GC. VEGF is the most extensively studied angiogenic factor. It is associated with the presence of neoplastic disease and lymph node metastasis. It appears to be a good biomarker for disease progression and remission, but not for diagnosis. The data regarding other biomarkers are inconclusive.

[Inhibitory effect of insulin-like growth factor binding protein-related protein 1 on retinal angiogenesis via ERK signaling pathway]

Objective: To explore the inhibitory effect of insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1), a novel anti-angiogenic factor, on retinal angiogenesis and its underlying molecular mechanisms. Methods: Experimental study. C57BL/6J mice were classified into three groups: control group (n=24), oxygen-induced retinopathy (OIR) non-intervention group (n=24) and OIR intervention group (n=72). The OIR mouse model was established using improved Smith's methods (n= 96). Twelve-day-old mice in the OIR intervention group were randomly assigned into three groups receiving intravitreal injection of recombinant mouse IGFBP-rP1 (50 μg/L, 100 μg/L and 200 μg/L, respectively). Five days later, the proliferative neovascular responses were estimated by quantifying the new vessel area relative to the total retinal area in flattening retinas stained by high molecular FITC-Dextran and counting the number of neovascular cell nuclei breaking through the internal limiting membrane (ILM) in cross-sections. Retinal phosphor-ERK1/2 (p-ERK1/2), ERK1/2 and vascular endothelial growth factor (VEGF) protein expression was assessed by Western blot. Results: In the fluorescence angiograms, irregular neovascularization and fluorescence leakage were observed in the OIR model. In the OIR non-intervention group, the expression of p-ERK1/2 and VEGF was significantly up-regulated in comparison with the control group (t=100.068, P=0.000. t=6.526, P=0.003). The area ratios of new retinal vessels and the number of neovascular cell nuclei in mice receiving intravitreal injection of recombinant mouse IGFBP-rP1 both decreased significantly (F=1920, P=0.000. F=852.387, P=0.000), following the down-regulation of retinal p-ERK1/2 protein expression (F=859.587, P=0.000) and VEGF protein expression (F=24.301, P= 0.000) in a dose-dependent manner (P<0.05). There was no significant difference in ERK1/2 protein expression (P>0.05). Conclusions: IGFBP-rP1 inhibits retinal angiogenesis by blocking ERK signaling pathway and down-regulating VEGF expression. This highlights the potential importance of IGFBP-rP1 serving as a target of gene therapy for retinal neovascularization. (Chin J Ophthalmol, 2017, 53: 207-211).