Research Progress of Targeted Ultrasound Contrast Agent BR55 / 中国医学科学院学报

BR55 is an ultrasound contrast agent targeting vascular endothelial growth factor receptor 2,which can be used to detect tumor neovascularization and improve the diagnostic accuracy.Overseas researchers have used BR55 for human ultrasound molecular imaging,which showed good safety and tolerance.We reviewed the research progress on BR55 applied in the evaluation of tumor neovascularization from the composition,characteristics,animal experiments,and clinical studies of BR55.

A comprehensive analysis of the angiogenesis-related genes in glioblastoma multiforme vs. brain lower grade glioma / Uma análise abrangente dos genes relacionados à angiogênese no glioblastoma multiforme vs. glioma cerebral de baixo grau

Abstract Brain tumors are one of the most common causes of cancer-related deaths around the world. Angiogenesis is critical in high-grade malignant gliomas, such as glioblastoma multiforme. Objective: The aim of this study is to comparatively analyze the angiogenesis-related genes, namely VEGFA, VEGFB, KDR, CXCL8, CXCR1 and CXCR2 in LGG vs. GBM to identify molecular distinctions using datasets available on The Cancer Genome Atlas (TCGA). Methods: DNA sequencing and mRNA expression data for 514 brain lower grade glioma (LGG) and 592 glioblastoma multiforme (GBM) patients were acquired from The Cancer Genome Atlas (TCGA), and the genetic alterations and expression levels of the selected genes were analyzed. Results: We identified six distinct KDR mutations in the LGG patients and 18 distinct KDR mutations in the GBM patients, including missense and nonsense mutations, frame shift deletion and altered splice region. Furthermore, VEGFA and CXCL8 were significantly overexpressed within GBM patients. Conclusions: VEGFA and CXCL8 are important factors for angiogenesis, which are suggested to have significant roles during tumorigenesis. Our results provide further evidence that VEGFA and CXCL8 could induce angiogenesis and promote LGG to progress into GBM. These findings could be useful in developing novel targeted therapeutics approaches in the future.

Resumo Os tumores cerebrais são uma das causas mais comuns de mortes relacionadas ao câncer em todo o mundo. A angiogênese tem caráter crítico em gliomas malignos de alto grau, como o glioblastoma multiforme. Objetivo: O objetivo deste estudo foi analisar comparativamente os genes relacionados à angiogênese, VEGFA, VEGFB, KDR, CXCL8, CXCR1 e CXCR2 em GBG vs. GBM para identificar distinções moleculares usando conjuntos de dados disponíveis no The Cancer Genome Atlas (TCGA). Métodos: Os dados de sequenciamento de DNA e expressão de mRNA para 514 pacientes com glioma cerebral de baixo grau (GBG) e 592 pacientes com glioblastoma multiforme (GBM) foram adquiridos do TCGA e as alterações genéticas e os níveis de expressão dos genes selecionados foram analisados. Resultados: Identificamos seis mutações KDR distintas nos pacientes GBG e 18 mutações KDR distintas nos pacientes GBM, incluindo mutações missense e nonsense, exclusão de mudança de quadro e região de emenda alterada. Além disso, VEGFA e CXCL8 foram significativamente super-expressos nos pacientes com GBM. Conclusões: VEGFA e CXCL8 são fatores importantes para a angiogênese, os quais parecem ter um papel significativo durante a tumorigênese. Nossos resultados fornecem evidências adicionais de que o VEGFA e o CXCL8 podem induzir a angiogênese e promover o GBG a progredir no GBM. Esses achados podem ser úteis no desenvolvimento de novas abordagens terapêuticas direcionadas no futuro.

Expresión de VEGF-A y VEGFR2 en Miocardio de Pollos Tratados con Ácido Acetilsalicílico (AAS) / VEGF-A and VEGFR2 Expression in Chicken Myocardium Treated with Acetylsalicylic Acid (AAS)

RESUMEN: Los niveles de VEGF y su unión a sus receptores son etapas claves en la regulación de la angiogénesis. El ácido acetilsalicílico (AAS), ampliamente utilizado en tratamiento post infarto al miocardio ha mostrado poseer un efecto antiangiogénico en modelos tumorales. Este efecto potencialmente contraproducente requiere ser estudiado en miocardio. El objetivo del presente trabajo es cuantificar el efecto de AAS y de ácido salicílico (AS) sobre la vascularización en membrana alantocoriónica (MAC) y sobre los niveles de VEGF-A y VEGFR2 en miocardio de embriones de pollo. Para ello, treinta fetos de pollo White Leghorn fueron instilados a los 10 días de gestación con 60 µL de DMSO 0,1 % (control) o conteniendo además 0,3 µmol de AAS o AS. A las 48 horas se realizó procesamiento histológico de MAC para recuento de vasos sanguíneos y de tejido cardíaco para cuantificar VEGF-A y VEGFR2 por inmunohistoquímica. La inmunorreactividad fue cuantificada mediante Image J. Tanto AAS como AS disminuyeron la densidad microvascular de MAC. En miocardio, AAS aunque no AS, disminuyó la concentración de VEGFR2. No hubo efecto sobre VEGF-A. En nuestro modelo experimental, fetos de pollo a los 10 días de gestación también se observó el efecto inhibidor de AAS sobre la angiogénesis en MAC. La disminución de VEGFR2 en cardiomiocitos sugiere que AAS también afecta la angiogénesis en miocardio sano, modificando la disponibilidad del receptor a VEGF. Estos hallazgos nos permiten postular que AAS podría interferir con la regeneración de tejido, en situaciones como post infarto al miocardio.

SUMMARY: The VEGF levels and its binding to its receptors are key stages in the regulation of angiogenesis. Acetylsalicylic acid (ASA), widely used in post-myocardial infarction treatment, has been shown to have an anti-angiogenic effect in tumor models. This potentially counterproductive effect requires to be studied in myocardium. The aim of this study is to quantify the effect of ASA and salicylic acid (SA) on the vascularization in chick allantochorionic membrane (CAM) and on the levels of VEGF-A and VEGFR2 in myocardium of chicken embryos. Thirty White Leghorn chicken fetuses were instilled at 10 days of gestation with 60 mL of 0.1 % DMSO (control) or also containing 0.3 mmol of ASA or SA. After 48 hours, CAM histological processing was performed to count blood vessels and heart tissue to quantify VEGFA and VEGFR2 by immunohistochemistry. Immunoreactivity was quantified by Image J. Both ASA and SA decreased CAM microvascular density. In myocardium, AAS, although not SA, decreased the concentration of VEGFR2. There was no effect on VEGF-A. In our experimental model, chicken fetuses at 10 days of gestation, the inhibitory effect of ASA on angiogenesis in CAM were also observed. The decrease in VEGFR2 in cardiomyocytes suggests that ASA also affects angiogenesis in healthy myocardium, modifying the availability of the receptor to VEGF. These findings allow us to postulate that ASA could interfere with tissue regeneration, when it is required, as post myocardial infarction.

Ventilation-induced changes correlate to pulmonary vascular response and VEGF, VEGFR-1/2, and eNOS expression in the rat model of postnatal hypoxia

Neonatal asphyxia occurs due to reduction in oxygen supply to vital organs in the newborn. Rapid restoration of oxygen to the lungs after a long period of asphyxia can cause lung injury and decline of respiratory function, which result from the activity of molecules that induce vascular changes in the lung such as nitric oxide (NO) and vascular endothelial growth factors (VEGF). In this study, we evaluated the pulmonary and vascular morphometry of rats submitted to the model of neonatal asphyxia and mechanical ventilation, their expression of pulmonary VEGF, VEGF receptors (VEGFR-1/VEGFR-2), and endothelial NO synthase (eNOS). Neonate Sprague-Dawley rats (CEUA #043/2011) were divided into four groups (n=8 each): control (C), control submitted to ventilation (CV), hypoxia (H), and hypoxia submitted to ventilation (HV). The fetuses were harvested at 21.5 days of gestation. The morphometric variables measured were body weight (BW), total lung weight (TLW), left lung weight (LLW), and TLW/BW ratio. Pulmonary vascular measurements, VEGFR-1, VEGFR-2, VEGF, and eNOS immunohistochemistry were performed. The morphometric analysis showed decreased TLW and TLW/BW ratio in HV compared to C and H (P<0.005). Immunohistochemistry showed increased VEGFR-2/VEGF and decreased VEGFR-1 expression in H (P<0.05) and lower eNOS expression in H and HV. Median wall thickness was increased in H, and the expression of VEGFR-1, VEGFR-2, VEGF, and eNOS was altered, especially in neonates undergoing H and HV. These data suggested the occurrence of arteriolar wall changes mediated by NO and VEGF signaling in neonatal hypoxia.

Estrogen deficiency in ovariectomized rats: can resistance training re-establish angiogenesis in visceral adipose tissue?

OBJECTIVE: The purpose of this study was to investigate the effects of resistance training on angiogenesis markers of visceral adipose tissue in ovariectomized rats. METHOD: Adult Sprague-Dawley female rats were divided into four groups (n=6 per group): sham-sedentary, ovariectomized sedentary, sham-resistance training and ovariectomized resistance training. The rats were allowed to climb a 1.1-m vertical ladder with weights attached to their tails and the weights were progressively increased. Sessions were performed three times per week for 10 weeks. Visceral adipose tissue angiogenesis and morphology were analyzed by histology. VEGF-A mRNA and protein levels were analyzed by real-time PCR and ELISA, respectively. RESULTS: Ovariectomy resulted in higher body mass (p=0.0003), adipocyte hypertrophy (p=0.0003), decreased VEGF-A mRNA (p=0.0004) and protein levels (p=0.0009), and decreased micro-vascular density (p=0.0181) in the visceral adipose tissue of the rats. Resistance training for 10 weeks was not able to attenuate the reduced angiogenesis in the visceral adipose tissue of the ovariectomized rats. CONCLUSION: Our findings indicate that the resistance training program used in this study could not ameliorate low angiogenesis in the visceral adipose tissue of ovariectomized rats.