RESUMO
Bevacizumab-induced hypertension poses a therapeutic challenge and identifying biomarkers for hypertension can enhance therapy safety. Lower plasma levels of VEGF-A, angiopoietin-2, and rs6770663 in KCNAB1 were previously associated with increased risk of bevacizumab-induced hypertension. This study investigated whether these factors independently contribute to grade 2-3 bevacizumab-induced hypertension risk in 277 cancer patients (CALGB/Alliance 90401). Multivariable analyses assessed the independent association of each factor and hypertension. Likelihood ratio test (LRT) evaluated the explanatory significance of combining protein levels and rs6770663 in predicting hypertension. Boostrap was employed to assess the mediation effect of protein levels on the rs6770663 association with hypertension. Lower protein levels and rs6770663 were independently associated with increased hypertension risk. Adding rs6770663 to protein levels improved the prediction of hypertension (LRT p = 0.0002), with no mediation effect observed. Protein levels of VEGF-A, angiopoietin-2 and rs6770663 in KCNAB1 are independent risk factors and, when combined, may improve prediction of bevacizumab-induced hypertension. ClinicalTrials.gov Identifier: NCT00110214.
Assuntos
Angiopoietina-2 , Bevacizumab , Hipertensão , Fator A de Crescimento do Endotélio Vascular , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Angiogênese/efeitos adversos , Angiopoietina-2/sangue , Angiopoietina-2/genética , Bevacizumab/efeitos adversos , Bevacizumab/uso terapêutico , Hipertensão/genética , Hipertensão/induzido quimicamente , Hipertensão/sangue , Neoplasias/tratamento farmacológico , Neoplasias/sangue , Neoplasias/genética , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , Canais de Potássio Shab/genética , Fator A de Crescimento do Endotélio Vascular/sangue , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
BACKGROUND: Angiopoietin-2 (Ang-2) is increased in the blood of patients with kaposiform lymphangiomatosis (KLA) and kaposiform hemangioendothelioma (KHE). While the genetic causes of KHE are not clear, a somatic activating NRASQ61R mutation has been found in the lesions of KLA patients. PROCEDURE: Our study tested the hypothesis that the NRASQ61R mutation drives elevated Ang-2 expression in endothelial cells. Ang-2 was measured in human endothelial progenitor cells (EPC) expressing NRASQ61R and a genetic mouse model with endothelial targeted NRASQ61R. To determine the signaling pathways driving Ang-2, NRASQ61R EPC were treated with signaling pathway inhibitors. RESULTS: Ang-2 levels were increased in EPC expressing NRASQ61R compared to NRASWT by Western blot analysis of cell lysates and ELISA of the cell culture media. Ang-2 levels were elevated in the blood of NRASQ61R mutant mice. NRASQ61R mutant mice also had reduced platelet counts and splenomegaly with hypervascular lesions, like some KLA patients. mTOR inhibitor rapamycin attenuated Ang-2 expression by NRASQ61R EPC. However, MEK1/2 inhibitor trametinib was more effective blocking increases in Ang-2. CONCLUSIONS: Our studies show that the NRASQ61R mutation in endothelial cells induces Ang-2 expression in vitro and in vivo. In cultured human endothelial cells, NRASQ61R drives elevated Ang-2 through MAP kinase and mTOR-dependent signaling pathways.
Assuntos
Angiopoietina-2 , Proteínas de Membrana , Animais , Humanos , Angiopoietina-2/genética , Angiopoietina-2/metabolismo , Camundongos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Mutação , Transdução de Sinais , Camundongos TransgênicosRESUMO
Abnormal angiogenesis leads to tumor progression and metastasis in colorectal cancer (CRC). This study aimed to elucidate the association between angiogenesis-related genes, including VEGF-A, ANGPT-1, and ANGPT-2 with both metastatic and microsatellite alterations at selected tetranucleotide repeats (EMAST) subtypes of CRC. We conducted a thorough assessment of the ANGPT-1, ANGPT-2, and VEGF-A gene expression utilizing publicly available RNA sequencing and microarray datasets. Then, the experimental validation was performed in 122 CRC patients, considering their disease metastasis and EMAST+/- profile by using reverse transcription polymerase chain reaction (RT-PCR). Subsequently, a competing endogenous RNA (ceRNA) network associated with these angiogenesis-related genes was constructed and analyzed. The expression level of VEGF-A and ANGPT-2 genes were significantly higher in tumor tissues as compared with normal adjacent tissues (P-value < 0.001). Nevertheless, ANGPT-1 had a significantly lower expression in tumor samples than in normal colon tissue (P-value < 0.01). We identified a significantly increased VEGF-A (P-value = 0.002) and decreased ANGPT-1 (P-value = 0.04) expression in EMAST+ colorectal tumors. Regarding metastasis, a significantly increased VEGF-A and ANGPT-2 expression (P-value = 0.001) and decreased ANGPT-1 expression (P-value < 0.05) were established in metastatic CRC patients. Remarkably, co-expression analysis also showed a strong correlation between ANGPT-2 and VEGF-A gene expressions. The ceRNA network was constructed by ANGPT-1, ANGPT-2, VEGF-A, and experimentally validated miRNAs (hsa-miR-190a-3p, hsa-miR-374c-5p, hsa-miR-452-5p, and hsa-miR-889-3p), lncRNAs (AFAP1-AS1, KCNQ1OT1 and MALAT1), and TFs (Sp1, E2F1, and STAT3). Network analysis revealed that colorectal cancer is amongst the 82 significant pathways. We demonstrated a significant differential expression of VEGF-A and ANGPT-1 in colorectal cancer patients exhibiting the EMAST+ phenotype. This finding provides novel insights into the molecular pathogenesis of colorectal cancer, specifically in EMAST subtypes. Yet, the generalization of in silico findings to EMAST+ colorectal cancer warrants future experimental investigations. In the end, this study proposes that the EMAST biomarker could serve as an additional perspective on CMS4 biology which is well-defined by activated angiogenesis and worse overall survival.
Assuntos
Angiopoietina-1 , Angiopoietina-2 , Neoplasias Colorretais , Regulação Neoplásica da Expressão Gênica , Neovascularização Patológica , Fator A de Crescimento do Endotélio Vascular , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Angiopoietina-1/genética , Angiopoietina-1/metabolismo , Angiopoietina-2/genética , Angiopoietina-2/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Metástase Neoplásica , Idoso , Repetições de Microssatélites/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , AngiogêneseRESUMO
Small cell lung cancer (SCLC) is the most aggressive lung cancer entity with an extremely limited therapeutic outcome. Most patients are diagnosed at an extensive stage. However, the molecular mechanisms driving SCLC invasion and metastasis remain largely elusive. We used an autochthonous SCLC mouse model and matched samples from patients with primary and metastatic SCLC to investigate the molecular characteristics of tumor metastasis. We demonstrate that tumor cell invasion and liver metastasis in SCLC are triggered by an Angiopoietin-2 (ANG-2)/Integrin ß-1-dependent pathway in tumor cells, mediated by focal adhesion kinase/Src kinase signaling. Strikingly, CRISPR-Cas9 KO of Integrin ß-1 or blocking Integrin ß-1 signaling by an anti-ANG-2 treatment abrogates liver metastasis formation in vivo. Interestingly, analysis of a unique collection of matched samples from patients with primary and metastatic SCLC confirmed a strong increase of Integrin ß-1 in liver metastasis in comparison with the primary tumor. We further show that ANG-2 blockade combined with PD-1-targeted by anti-PD-1 treatment displays synergistic treatment effects in SCLC. Together, our data demonstrate a fundamental role of ANG-2/Integrin ß-1 signaling in SCLC cells for tumor cell invasion and liver metastasis and provide a potentially new effective treatment strategy for patients with SCLC.
Assuntos
Angiopoietina-2 , Integrina beta1 , Neoplasias Hepáticas , Neoplasias Pulmonares , Transdução de Sinais , Carcinoma de Pequenas Células do Pulmão , Animais , Feminino , Humanos , Masculino , Camundongos , Angiopoietina-2/metabolismo , Angiopoietina-2/genética , Linhagem Celular Tumoral , Integrina beta1/metabolismo , Integrina beta1/genética , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamento farmacológico , Invasividade Neoplásica , Metástase Neoplásica , Carcinoma de Pequenas Células do Pulmão/patologia , Carcinoma de Pequenas Células do Pulmão/metabolismo , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológicoRESUMO
INTRODUCTION: Critical illness is associated with organ failure, in which endothelial hyperpermeability and tissue edema play a major role. The endothelial angiopoietin/Tie2 system, a regulator of endothelial permeability, is dysbalanced during critical illness. Elevated circulating angiopoietin-2 and decreased Tie2 receptor levels are reported, but it remains unclear whether they cause edema independent of other critical illness-associated alterations. Therefore, we have studied the effect of angiopoietin-2 administration and/or reduced Tie2 expression on microvascular leakage and edema under normal conditions. METHODS: Transgenic male mice with partial deletion of Tie2 (heterozygous exon 9 deletion, Tie2+/-) and wild-type controls (Tie2+/+) received 24 or 72 pg/g angiopoietin-2 or PBS as control (n = 12 per group) intravenously. Microvascular leakage and edema were determined by Evans blue dye (EBD) extravasation and wet-to-dry weight ratio, respectively, in lungs and kidneys. Expression of molecules related to endothelial angiopoietin/Tie2 signaling were determined by ELISA and RT-qPCR. RESULTS: In Tie2+/+ mice, angiopoietin-2 administration increased EBD extravasation (154 %, p < 0.05) and wet-to-dry weight ratio (133 %, p < 0.01) in lungs, but not in the kidney compared to PBS. Tie2+/- mice had higher pulmonary (143 %, p < 0.001), but not renal EBD extravasation, compared to wild-type control mice, whereas a more pronounced wet-to-dry weight ratio was observed in lungs (155 %, p < 0.0001), in contrast to a minor higher wet-to-dry weight ratio in kidneys (106 %, p < 0.05). Angiopoietin-2 administration to Tie2+/- mice did not further increase pulmonary EBD extravasation, pulmonary wet-to-dry weight ratio, or renal wet-to-dry weight ratio. Interestingly, angiopoietin-2 administration resulted in an increased renal EBD extravasation in Tie2+/- mice compared to Tie2+/- mice receiving PBS. Both angiopoietin-2 administration and partial deletion of Tie2 did not affect circulating angiopoietin-1, soluble Tie2, VEGF and NGAL as well as gene expression of angiopoietin-1, -2, Tie1, VE-PTP, ELF-1, Ets-1, KLF2, GATA3, MMP14, Runx1, VE-cadherin, VEGFα and NGAL, except for gene and protein expression of Tie2, which was decreased in Tie2+/- mice compared to Tie2+/+ mice. CONCLUSIONS: In mice, the microvasculature of the lungs is more vulnerable to angiopoietin-2 and partial deletion of Tie2 compared to those in the kidneys with respect to microvascular leakage and edema.
Assuntos
Angiopoietina-2 , Permeabilidade Capilar , Pulmão , Receptor TIE-2 , Animais , Receptor TIE-2/metabolismo , Receptor TIE-2/genética , Angiopoietina-2/metabolismo , Angiopoietina-2/genética , Masculino , Pulmão/irrigação sanguínea , Pulmão/metabolismo , Pulmão/patologia , Rim/irrigação sanguínea , Rim/metabolismo , Transdução de Sinais , Camundongos Knockout , Camundongos , Camundongos Endogâmicos C57BL , Edema Pulmonar/metabolismo , Edema Pulmonar/genética , Edema Pulmonar/patologia , Edema Pulmonar/induzido quimicamente , Edema Pulmonar/fisiopatologia , Modelos Animais de Doenças , Edema/metabolismo , Camundongos Transgênicos , Ribonuclease PancreáticoRESUMO
This paper aims to explore the effect of Xuming Decoction in the Records of Proved Prescriptions, Ancient and Modern on cerebral ischemic injury and angiogenesis in the rat model of acute cerebral infarction. SD rats were randomized into 6 groups: sham group, model group, low-, medium-, and high-dose(5.13, 10.26, and 20.52 g·kg~(-1), respectively) Xuming Decoction groups, and butylphthalide(0.06 g·kg~(-1)) group. After the successful establishment of the rat model by middle cerebral artery occlusion(MCAO), rats in the sham and model groups were administrated with distilled water and those in other groups with corresponding drugs for 7 consecutive days. After the neurological function was scored, all the rats were sacrificed, and the brain tissue samples were collected. The degree of cerebral ischemic injury was assessed by the neurological deficit score and staining with 2,3,5-triphenyltetrazolium chloride. Hematoxylin-eosin staining was performed to observe the pathological changes in the brain. Transmission electron microscopy was employed to observe the ultrastructures of neurons and microvascular endothelial cells(ECs) on the ischemic side of the brain tissue. Immunofluorescence assay was employed to detect the expression of von Willebrand factor(vWF) and hematopoietic progenitor cell antigen CD34(CD34) in the ischemic brain tissue. Real-time PCR and Western blot were employed to determine the mRNA and protein levels, respectively, of Runt-related transcription factor 1(RUNX1), vascular endothelial growth factor(VEGF), angiopoietin-1(Ang-1), angiopoietin-2(Ang-2), and VEGF receptor 2(VEGFR2) in the ischemic brain tissue. The results showed that compared with the sham group, the model group showed increased neurological deficit score and cerebral infarction area(P<0.01), pathological changes, and damaged ultrastructure of neurons and microvascular ECs in the ischemic brain tissue. Furthermore, the modeling up-regulated the mRNA levels of RUNX1, VEGF, Ang-1, Ang-2, and VEGFR2(P<0.01) and the protein levels of vWF, CD34, RUNX1, VEGF, Ang-1, Ang-2, and VEGFR2(P<0.05 or P<0.01). Compared with the model group, high-dose Xuming Decoction and butylphthalide decreased the neurological deficit score and cerebral infarction area(P<0.01) and alleviated the pathological changes and damage of the ultrastructure of neurons and microvascular ECs in the ischemic brain tissue. Moreover, they up-regulated the mRNA levels of RUNX1, VEGF, Ang-1, Ang-2, and VEGFR2(P<0.01) and the protein levels of vWF, CD34, RUNX1, VEGF, Ang-1, Ang-2, and VEGFR2(P<0.01). The results suggest that Xuming Decoction in the Records of Proved Prescriptions, Ancient and Modern can promote the angiogenesis and collateral circulation establishment to alleviate neurological dysfunction of the ischemic brain tissue in MCAO rats by regulating the RUNX1/VEGF pathway.
Assuntos
Isquemia Encefálica , Infarto Cerebral , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas , Ratos Sprague-Dawley , Animais , Ratos , Masculino , Medicamentos de Ervas Chinesas/farmacologia , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/metabolismo , Infarto Cerebral/genética , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/genética , Humanos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Angiopoietina-2/genética , Angiopoietina-2/metabolismo , AngiogêneseRESUMO
Lymphedema is a debilitating disease with no effective cure and affects an estimated 250 million individuals worldwide. Prior studies have identified mutations in piezo-type mechanosensitive ion channel component 1 (PIEZO1), angiopoietin 2 (ANGPT2), and tyrosine kinase with Ig-like and EGF-like domains 1 (TIE1) in patients with primary lymphedema. Here, we identified crosstalk between these molecules and showed that activation of the mechanosensory channel PIEZO1 in lymphatic endothelial cells (LECs) caused rapid exocytosis of the TIE ligand ANGPT2, ectodomain shedding of TIE1 by disintegrin and metalloproteinase domain-containing protein 17 (ADAM17), and increased TIE/PI3K/AKT signaling, followed by nuclear export of the transcription factor FOXO1. These data establish a functional network between lymphedema-associated genes and provide what we believe to be the first molecular mechanism bridging channel function with vascular signaling and intracellular events culminating in transcriptional regulation of genes expressed in LECs. Our study provides insights into the regulation of lymphatic function and molecular pathways involved in human disease.
Assuntos
Angiopoietina-2 , Proteína Forkhead Box O1 , Canais Iônicos , Linfangiogênese , Linfedema , Receptor de TIE-1 , Transdução de Sinais , Animais , Humanos , Camundongos , Proteína ADAM17/metabolismo , Proteína ADAM17/genética , Angiopoietina-2/metabolismo , Angiopoietina-2/genética , Células Endoteliais/metabolismo , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/genética , Canais Iônicos/metabolismo , Canais Iônicos/genética , Linfangiogênese/genética , Linfedema/metabolismo , Linfedema/genética , Linfedema/patologia , Mecanotransdução Celular , Receptor de TIE-1/metabolismo , Receptor de TIE-1/genéticaRESUMO
OBJECTIVE: Moyamoya angiopathy (MA) is a rare cerebrovascular disorder characterized by recurrent ischemic/hemorrhagic strokes due to progressive occlusion of the intracranial carotid arteries. The lack of reliable disease severity biomarkers led us to investigate molecular features of a Caucasian cohort of MA patients. METHODS: The participants consisted of 30 MA patients and 40 controls. We measured cerebrospinal fluid (CSF) levels of angiogenic/inflammatory factors (ELISA). We then applied quantitative real-time PCR on cerebral artery specimens for expression analyses of angiogenic factors. By an immunoassay based on microfluidic technology, we examined the potential correlations between plasma protein expression and MA clinical progression. A RNA interference approach toward Ring Finger Protein 213 (RNF213) and a tube formation assay were applied in cellular model. RESULTS: We detected a statistically significant (p < 0.000001) up-regulation of Angiopoietin-2 (Ang-2) in CSF and stenotic middle cerebral arteries (RQ >2) of MA patients compared to controls. A high Ang-2 plasma concentration (p = 0.018) was associated with unfavorable outcome in a subset of MA patients. ROC curve analyses indicated Ang-2 as diagnostic CSF biomarker (>3741 pg/mL) and prognostic plasma biomarker (>1162 pg/mL), to distinguish stable-from-progressive MA. Consistently, MA cellular model showed a significant up-regulation (RQ >2) of Ang-2 in RNF213 silenced condition. INTERPRETATION: Our results pointed out Ang-2 as a reliable biomarker mirroring arterial steno-occlusion and vascular instability of MA in CSF and blood, providing a candidate factor for patient stratification. This pilot study may pave the way to the validation of a biomarker to identify progressive MA patients deserving a specific treatment path.
Assuntos
Angiopoietina-2 , Doença de Moyamoya , Humanos , Doença de Moyamoya/genética , Doença de Moyamoya/líquido cefalorraquidiano , Doença de Moyamoya/diagnóstico , Angiopoietina-2/líquido cefalorraquidiano , Angiopoietina-2/genética , Angiopoietina-2/sangue , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Prognóstico , Biomarcadores/líquido cefalorraquidiano , Biomarcadores/sangue , Ubiquitina-Proteína Ligases/genética , Adulto Jovem , Adenosina TrifosfatasesRESUMO
PURPOSE: Angiopoietin (Ang) 2 is released from vascular endothelial cells by the stimulation of vascular endothelial growth factor (VEGF)A. Ang2 increases the expression of leukocyte adhesion molecules on endothelial cells via nuclear factor κB. The aim of this study was to evaluate the effects of Ang2 and VEGFA on ocular autoimmune inflammation. METHODS: We measured the concentrations of Ang2 and VEGFA in vitreous samples among patients with uveitis. Vitreous samples were collected from 16 patients with idiopathic uveitis (uveitis group) and 16 patients with non-inflammatory eye disease (control group). Experimental autoimmune uveoretinitis (EAU) was induced in B10.BR mice with a human interphotoreceptor retinoid-binding protein-derived peptide. The retinochoroidal tissues of the EAU mice were removed, and the mRNA levels of Ang2 and VEGFA were examined. EAU mice treated with anti-Ang2, anti-VEGFA, a combination of anti-Ang2 and anti-VEGFA, anti-Ang2/VEGFA bispecific, or IgG control antibodies were clinically and histopathologically evaluated. RESULTS: The protein levels of Ang2 and VEGFA were significantly higher in the vitreous samples of patients with uveitis than in controls (P<0.05). The retinochoroidal mRNA levels of Ang2 and VEGFA were significantly upregulated in EAU mice compared to controls (n = 6, P<0.05). Although there was no significant difference, treatment with anti-VEGFA antibody reduced the clinical and histopathological scores. However, treatment with anti-Ang2 antibody reduced the clinical and histopathological scores (n = 18-20, P<0.05). Furthermore, these scores were further decreased when treated by inhibiting both Ang2 and VEGFA. CONCLUSIONS: Based on these results, VEGFA and Ang2 were shown to be upregulated locally in the eye of both uveitis patients and models of uveitis. Dual inhibition of Ang2 and VEGFA is suggested to be a new therapeutic strategy for uveitis.
Assuntos
Doenças Autoimunes , Uveíte , Animais , Humanos , Camundongos , Angiopoietina-2/genética , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Inflamação/patologia , RNA Mensageiro/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fatores de Crescimento do Endotélio VascularRESUMO
BACKGROUND: The endothelial angiopoietin/Tie2 system is an important regulator of endothelial permeability and targeting Tie2 reduces hemorrhagic shock-induced organ edema in males. However, sexual dimorphism of the endothelium has not been taken into account. This study investigated whether there are sex-related differences in the endothelial angiopoietin/Tie2 system and edema formation. METHODS: Adult male and female heterozygous Tie2 knockout mice (Tie2+/-) and wild-type controls (Tie2+/+) were included (n = 9 per group). Renal and pulmonary injury were determined by wet/dry weight ratio and H&E staining of tissue sections. Protein levels were studied in plasma by ELISA and pulmonary and renal mRNA expression levels by RT-qPCR. RESULTS: In Tie2+/+ mice, females had higher circulating angiopoietin-2 (138%, p<0.05) compared to males. Gene expression of angiopoietin-1 (204%, p<0.01), angiopoietin-2 (542%, p<0.001) were higher in females compared to males in kidneys, but not in lungs. Gene expression of Tie2, Tie1 and VE-PTP were similar between males and females in both organs. Renal and pulmonary wet/dry weight ratio did not differ between Tie2+/+ females and males. Tie2+/+ females had lower circulating NGAL (41%, p<0.01) compared to males, whereas renal NGAL and KIM1 gene expression was unaffected. Interestingly, male Tie2+/- mice had 28% higher renal wet/dry weight ratio (p<0.05) compared to Tie2+/+ males, which was not observed in females nor in lungs. Partial deletion of Tie2 did not affect circulating angiopoietin-1 or angiopoietin-2, but soluble Tie2 was 44% and 53% lower in males and females, respectively, compared to Tie2+/+ mice of the same sex. Renal and pulmonary gene expression of angiopoietin-1, angiopoietin-2, estrogen receptors and other endothelial barrier regulators was comparable between Tie2+/- and Tie2+/+ mice in both sexes. CONCLUSION: Female sex seems to protect against renal, but not pulmonary edema in heterozygous Tie2 knock-out mice. This could not be explained by sex dimorphism in the endothelial angiopoietin/Tie2 system.
Assuntos
Angiopoietina-1 , Angiopoietina-2 , Animais , Feminino , Masculino , Camundongos , Angiopoietina-1/genética , Angiopoietina-1/metabolismo , Angiopoietina-2/genética , Angiopoietina-2/metabolismo , Angiopoietinas , Edema , Endotélio/metabolismo , Rim/metabolismo , Lipocalina-2 , Receptor TIE-2/genética , Receptor TIE-2/metabolismoRESUMO
Improving the management of metastasis in pancreatic neuroendocrine tumors (PanNETs) is critical, as nearly half of patients with PanNETs present with liver metastases, and this accounts for the majority of patient mortality. We identified angiopoietin-2 (ANGPT2) as one of the most upregulated angiogenic factors in RNA-Seq data from human PanNET liver metastases and found that higher ANGPT2 expression correlated with poor survival rates. Immunohistochemical staining revealed that ANGPT2 was localized to the endothelial cells of blood vessels in PanNET liver metastases. We observed an association between the upregulation of endothelial ANGPT2 and liver metastatic progression in both patients and transgenic mouse models of PanNETs. In human and mouse PanNET liver metastases, ANGPT2 upregulation coincided with poor T cell infiltration, indicative of an immunosuppressive tumor microenvironment. Notably, both pharmacologic inhibition and genetic deletion of ANGPT2 in PanNET mouse models slowed the growth of PanNET liver metastases. Furthermore, pharmacologic inhibition of ANGPT2 promoted T cell infiltration and activation in liver metastases, improving the survival of mice with metastatic PanNETs. These changes were accompanied by reduced plasma leakage and improved vascular integrity in metastases. Together, these findings suggest that ANGPT2 blockade may be an effective strategy for promoting T cell infiltration and immunostimulatory reprogramming to reduce the growth of liver metastases in PanNETs.
Assuntos
Neoplasias Hepáticas , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Animais , Humanos , Camundongos , Angiopoietina-2/genética , Angiopoietina-2/metabolismo , Células Endoteliais/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Camundongos Transgênicos , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Linfócitos T/patologia , Microambiente TumoralRESUMO
Defining reliable surrogate markers and overcoming drug resistance are the most challenging issues for improving therapeutic outcomes of antiangiogenic drugs (AADs) in cancer patients. At the time of this writing, no biomarkers are clinically available to predict AAD therapeutic benefits and drug resistance. Here, we uncovered a unique mechanism of AAD resistance in epithelial carcinomas with KRAS mutations that targeted angiopoietin 2 (ANG2) to circumvent antivascular endothelial growth factor (anti-VEGF) responses. Mechanistically, KRAS mutations up-regulated the FOXC2 transcription factor that directly elevated ANG2 expression at the transcriptional level. ANG2 bestowed anti-VEGF resistance as an alternative pathway to augment VEGF-independent tumor angiogenesis. Most colorectal and pancreatic cancers with KRAS mutations were intrinsically resistant to monotherapies of anti-VEGF or anti-ANG2 drugs. However, combination therapy with anti-VEGF and anti-ANG2 drugs produced synergistic and potent anticancer effects in KRAS-mutated cancers. Together, these data demonstrate that KRAS mutations in tumors serve as a predictive marker for anti-VEGF resistance and are susceptible to combination therapy with anti-VEGF and anti-ANG2 drugs.
Assuntos
Carcinoma , Fatores de Crescimento Endotelial , Humanos , Fatores de Crescimento Endotelial/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Angiopoietina-2/genética , Angiopoietina-2/metabolismo , Angiopoietina-1/metabolismoRESUMO
The endocannabinoid system receptors, cannabinoid receptors type-1 (CBR-1) and -2 (CBR-2), are implicated in several behavioral and cognitive processes. Many studies have indicated a correlation between cannabinoid receptors and angiogenesis. The current study aims to reveal the possible molecular signaling involved in brain angiogenesis induced by the activation of CBR-1 and CBR-2. We investigated whether the synthetic cannabinoid XLR-11, an agonist of CBR-1 and CBR-2, influences the mRNA and protein expression of vascular endothelial growth factor (VEGF), angiopoietin-1 (ANG1) and -2 (ANG2) in human brain microvascular endothelial cells (hBMVEs). Furthermore, we determined the phosphorylation of glycogen synthase kinase 3 beta (GSK3B) expression. Treatment of hBMVEs cells with XLR-11 elevated the mRNA levels of VEGF, ANG1, and ANG2. The secretion of these proangiogenic factors was increased in the media. Furthermore, the intracellular expression of VEGF, ANG1, ANG2, and GSK3B was significantly increased. This current research provides a new possible approach by targeting the cannabinoid receptors to control and regulate brain angiogenesis for treating a variety of angiogenesis-related diseases. This could be achived by using different agonists or antagonists of the cannabinoid receptors based on the nature of the diseases.
Assuntos
Canabinoides , Fator A de Crescimento do Endotélio Vascular , Humanos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Células Endoteliais/metabolismo , Angiopoietina-1/genética , Angiopoietina-1/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Canabinoides/farmacologia , RNA Mensageiro/metabolismo , Encéfalo/metabolismo , Receptores de Canabinoides/metabolismo , Angiopoietina-2/genética , Angiopoietina-2/metabolismo , Receptor TIE-2/metabolismoRESUMO
Background: Angiopoietin-2 (Ang2)-mediated angiogenesis plays a crucial role in the pathogenesis of vascular-rich cancers. However, the genetic polymorphism and expression level of Ang2 in patients with primary liver cancer remain unknown. Methods: This study included 234 primary liver cancer patients and 199 healthy controls. The expression levels of Ang2 in liver cancer tissues and plasma were determined. Peripheral blood samples were collected to test five ANGPT2 single nucleotide polymorphisms (rs2442598, rs734701, rs1823375, rs11137037, and rs12674822). Results: Plasma Ang2 levels in patients with liver cancer were upregulated compared with that in healthy controls. The upregulation of plasma Ang2 levels was significantly associated with vascular invasion, metastasis, and clinical stage. Notably, the transcription level of ANGPT2 was elevated in tumor tissues compared with para-carcinoma tissues. Individuals with the TT genotype at rs2442598 and genotype AC and AC+CC at rs11137037 had higher liver cancer risk compared with healthy controls. Conclusions: Upregulated Ang2 levels in blood plasma and cancer tissues of liver cancer patients confirm that Ang2 plays a vital role in the pathogenesis of liver cancer. ANGPT2 rs2442588 and rs11137037 are associated with liver cancer risk, thereby highlighting their role in screening individuals susceptible to liver cancer.
Assuntos
Angiopoietina-2 , Neoplasias Hepáticas , Humanos , Angiopoietina-2/biossíntese , Angiopoietina-2/genética , População do Leste Asiático , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
BACKGROUND: Hereditary hemorrhagic telangiectasia (HHT) is a vascular disorder characterized by arteriovenous malformations and blood vessel enlargements. However, there are no effective drug therapies to combat arteriovenous malformation formation in patients with HHT. Here, we aimed to address whether elevated levels of ANG2 (angiopoietin-2) in the endothelium is a conserved feature in mouse models of the 3 major forms of HHT that could be neutralized to treat brain arteriovenous malformations and associated vascular defects. In addition, we sought to identify the angiogenic molecular signature linked to HHT. METHODS: Cerebrovascular defects, including arteriovenous malformations and increased vessel calibers, were characterized in mouse models of the 3 common forms of HHT using transcriptomic and dye injection labeling methods. RESULTS: Comparative RNA sequencing analyses of isolated brain endothelial cells revealed a common, but unique proangiogenic transcriptional program associated with HHT. This included a consistent upregulation in cerebrovascular expression of ANG2 and downregulation of its receptor Tyr kinase with Ig and EGF homology domains (TIE2/TEK) in HHT mice compared with controls. Furthermore, in vitro experiments revealed TEK signaling activity was hampered in an HHT setting. Pharmacological blockade of ANG2 improved brain vascular pathologies in all HHT models, albeit to varying degrees. Transcriptomic profiling further indicated that ANG2 inhibition normalized the brain vasculature by impacting a subset of genes involved in angiogenesis and cell migration processes. CONCLUSIONS: Elevation of ANG2 in the brain vasculature is a shared trait among the mouse models of the common forms of HHT. Inhibition of ANG2 activity can significantly limit or prevent brain arteriovenous malformation formation and blood vessel enlargement in HHT mice. Thus, ANG2-targeted therapies may represent a compelling approach to treat arteriovenous malformations and vascular pathologies related to all forms of HHT.
Assuntos
Malformações Arteriovenosas , Telangiectasia Hemorrágica Hereditária , Animais , Camundongos , Telangiectasia Hemorrágica Hereditária/tratamento farmacológico , Telangiectasia Hemorrágica Hereditária/genética , Células Endoteliais/metabolismo , Angiopoietina-2/genética , Angiopoietina-2/metabolismo , Malformações Arteriovenosas/metabolismo , FenótipoRESUMO
Purpose: Anti-vascular endothelial growth factor (anti-VEGF) therapies, which attenuate the capacity of VEGF to bind to VEGF receptors, are standard-of-care options for various retinal disorders that are characterized by pathologic retinal angiogenesis and vascular permeability. Multiple receptors and ligands have also been reported as being involved in these pathways, including angiopoietin-1 (ANG1) and angiopoietin-2 (ANG2). Methods: Electrochemiluminescence immunoassays were used to detect human VEGF (hVEGF), as well as rabbit ANG2 and basic fibroblast growth factor protein levels in vitreous samples derived from a study evaluating the efficacy of the anti-VEGF agents ranibizumab, aflibercept, and brolucizumab in an hVEGF165-induced rabbit retinal vascular hyperpermeability model. Results: hVEGF was completely suppressed in rabbit vitreous after anti-VEGF treatment for 28 days. ANG2 protein in vitreous and ANGPT2 mRNA in retina tissue were similarly suppressed, although the anti-VEGF agents do not directly bind to ANG2. Aflibercept demonstrated the greatest inhibitory effect in ANG2 levels in vitreous, which correlated with strong, durable suppression of intraocular hVEGF levels. Conclusions: This study explored the effects of anti-VEGF therapies beyond direct binding of VEGF by evaluating protein levels and the expression of target genes involved in angiogenesis and associated molecular mechanisms in the rabbit retina and choroid. Translational Relevance: In vivo data suggest that anti-VEGF agents currently used for the treatment of retinal diseases could provide beneficial effects beyond direct binding of VEGF, including suppression of ANG2 protein and ANGPT2 mRNA.
Assuntos
Angiopoietina-2 , Fator A de Crescimento do Endotélio Vascular , Animais , Coelhos , Humanos , Fator A de Crescimento do Endotélio Vascular/genética , Angiopoietina-2/genética , Angiopoietina-2/metabolismo , Fatores de Crescimento do Endotélio Vascular , Receptores de Fatores de Crescimento do Endotélio Vascular , Neovascularização Patológica , RNA Mensageiro/metabolismoRESUMO
T-cell position in the tumor microenvironment determines the probability of target encounter and tumor killing. CD8+ T-cell exclusion from the tumor parenchyma is associated with poor response to immunotherapy, and yet the biology that underpins this distinct pattern remains unclear. Here we show that the vascular destabilizing factor angiopoietin-2 (ANGPT2) causes compromised vascular integrity in the tumor periphery, leading to impaired T-cell infiltration to the tumor core. The spatial regulation of ANGPT2 in whole tumor cross-sections was analyzed in conjunction with T-cell distribution, vascular integrity, and response to immunotherapy in syngeneic murine melanoma models. T-cell exclusion was associated with ANGPT2 upregulation and elevated vascular leakage at the periphery of human and murine melanomas. Both pharmacologic and genetic blockade of ANGPT2 promoted CD8+ T-cell infiltration into the tumor core, exerting antitumor effects. Importantly, the reversal of T-cell exclusion following ANGPT2 blockade not only enhanced response to anti-PD-1 immune checkpoint blockade therapy in immunogenic, therapy-responsive mouse melanomas, but it also rendered nonresponsive tumors susceptible to immunotherapy. Therapeutic response after ANGPT2 blockade, driven by improved CD8+ T-cell infiltration to the tumor core, coincided with spatial TIE2 signaling activation and increased vascular integrity at the tumor periphery where endothelial expression of adhesion molecules was reduced. These data highlight ANGPT2/TIE2 signaling as a key mediator of T-cell exclusion and a promising target to potentiate immune checkpoint blockade efficacy in melanoma. SIGNIFICANCE: ANGPT2 limits the efficacy of immunotherapy by inducing vascular destabilization at the tumor periphery to promote T-cell exclusion.
Assuntos
Angiopoietina-2 , Melanoma , Humanos , Camundongos , Animais , Angiopoietina-2/genética , Inibidores de Checkpoint Imunológico , Melanoma/terapia , Imunoterapia , Linfócitos T CD8-Positivos/metabolismo , Microambiente TumoralRESUMO
Helicobacter pylori colonizes the stomach and induces an inflammatory response that can develop into gastric pathologies including cancer. The infection can alter the gastric vasculature by the deregulation of angiogenic factors and microRNAs. In this study, we investigate the expression level of pro-angiogenic genes (ANGPT2, ANGPT1, receptor TEK), and microRNAs (miR-135a, miR-200a, miR-203a) predicted to regulate those genes, using H. pylori co-cultures with gastric cancer cell lines. In vitro infections of different gastric cancer cell lines with H. pylori strains were performed, and the expression of ANGPT1, ANGPT2, and TEK genes, and miR-135a, miR-200a, and miR-203a, was quantified after 24 h of infection (h.p.i.). We performed a time course experiment of H. pylori 26695 infections in AGS cells at 6 different time points (3, 6, 12, 28, 24, and 36 h.p.i.). The angiogenic response induced by supernatants of non-infected and infected cells at 24 h.p.i. was evaluated in vivo, using the chicken chorioallantoic membrane (CAM) assay. In response to infection, ANGPT2 mRNA was upregulated at 24 h.p.i, and miR-203a was downregulated in AGS cells co-cultured with different H. pylori strains. The time course of H. pylori 26695 infection in AGS cells showed a gradual decrease of miR-203a expression concomitant with an increase of ANGPT2 mRNA and protein expression. Expression of ANGPT1 and TEK mRNA or protein could not be detected in any of the infected or non-infected cells. CAM assays showed that the supernatants of AGS-infected cells with 26695 strain induced a significantly higher angiogenic and inflammatory response. Our results suggest that H. pylori could contribute to the process of carcinogenesis by downregulating miR-203a, which further promotes angiogenesis in gastric mucosa by increasing ANGPT2 expression. Further investigation is needed to elucidate the underlying molecular mechanisms.
Assuntos
Infecções por Helicobacter , Helicobacter pylori , MicroRNAs , Neoplasias Gástricas , Humanos , Angiopoietina-2/genética , Angiopoietina-2/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/complicações , Helicobacter pylori/genética , MicroRNAs/genética , RNA Mensageiro/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismoRESUMO
Rheumatoid arthritis (RA) is an inflammatory autoimmune disease that destroys joint cartilage and causes disability. Synovial inflammation, with angiogenesis, is an early event in the progression of the disease. Angiopoietin 2 (ANGPT2) is a cytokine with both inflammatory and angiogenic effects. Many genes can influence RA susceptibility and disease activity. The aim is to assess the relationship between ANGPT2 gene polymorphism (rs3020221) and RA. The study was a case-control study that included 212 RA patients and 238 age-and gender-matched healthy volunteers. RA disease activity was assessed using the Disease Activity Score 28 index. Erythrocyte sedimentation rate, C-reactive protein, rheumatoid factor, and antibody to cyclic citrullinated peptide were measured. ANGPT2 rs3020221 C > T SNP genotyping was done using real-time polymerase chain reaction (PCR). The TT genotype was more frequently represented in RA patients than in healthy controls (18.9% and 7.1%, respectively, p < 0.001) and increased the chance of developing RA four-fold, as compared to other genotypes (OR = 4.00, 95% CI = 2.09-7.63) (p < 0.001). The CT genotype was associated with elevated levels of the inflammatory markers ESR and CRP in RA patients (p = 0.012 and 0.037, respectively) as well as the DAS28 ESR Score (p < 0.001). The presence of the T allele either under the dominant model (for genotypes CT and TT) or the recessive model (for the genotype TT) predicts RA disease. Assessment of ANGPT2 gene polymorphism is useful to predict the patients with susceptibility to RA. The presence of T allele increased the risk of developing RA disease by two folds.
Assuntos
Artrite Reumatoide , Polimorfismo de Nucleotídeo Único , Humanos , Angiopoietina-2/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/genética , Genótipo , Fator ReumatoideRESUMO
Vascular homeostasis is impaired in various diseases thereby contributing to the progression of their underlying pathologies. The endothelial immediate early gene Apolipoprotein L domain-containing 1 (APOLD1) helps to regulate endothelial function. However, its precise role in endothelial cell biology remains unclear. We have localized APOLD1 to endothelial cell contacts and to Weibel-Palade bodies (WPB) where it associates with von Willebrand factor (VWF) tubules. Silencing of APOLD1 in primary human endothelial cells disrupted the cell junction-cytoskeletal interface, thereby altering endothelial permeability accompanied by spontaneous release of WPB contents. This resulted in an increased presence of WPB cargoes, notably VWF and angiopoietin-2 in the extracellular medium. Autophagy flux, previously recognized as an essential mechanism for the regulated release of WPB, was impaired in the absence of APOLD1. In addition, we report APOLD1 as a candidate gene for a novel inherited bleeding disorder across three generations of a large family in which an atypical bleeding diathesis was associated with episodic impaired microcirculation. A dominant heterozygous nonsense APOLD1:p.R49* variant segregated to affected family members. Compromised vascular integrity resulting from an excess of plasma angiopoietin-2, and locally impaired availability of VWF may explain the unusual clinical profile of APOLD1:p.R49* patients. In summary, our findings identify APOLD1 as an important regulator of vascular homeostasis and raise the need to consider testing of endothelial cell function in patients with inherited bleeding disorders without apparent platelet or coagulation defects.