InVivoMAb anti-mouse VEGFR-2

Catalog #BE0060
Product Citations:
38
Clone:
DC101
Reactivities:
Mouse

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Product Details

The DC101 monoclonal antibody reacts with mouse VEGFR-2 (vascular endothelial growth factor receptor 2) also known as CD309, KDR, and Flk-1. VEGFR-2 is a member of the tyrosine protein kinase family. Upon binding to its ligand VEGF, VEGFR-2 pays key roles in vascular development and permeability. VEGFR-2 is expressed on endothelial cells at high levels in adult heart, lung, kidney, brain, and skeletal muscle as well as other tissues at lower levels. The DC101 antibody has been shown to inhibit VEGFR-2 signaling in vivo.

Specifications

Isotype Rat IgG1, κ
Recommended Isotype Control(s) InVivoMAb rat IgG1 isotype control, anti-horseradish peroxidase
Recommended Dilution Buffer InVivoPure pH 7.0 Dilution Buffer
Conjugation This product is unconjugated. Conjugation is available via our Antibody Conjugation Services.
Immunogen Mouse VEGFR-2-SEAPs soluble receptor
Reported Applications in vivo blocking of VEGF/VEGFR-2 signaling
in vitro blocking of VEGFR signaling
Western blot
Formulation PBS, pH 7.0
Contains no stabilizers or preservatives
Endotoxin <2EU/mg (<0.002EU/μg)
Determined by LAL gel clotting assay
Purity >95%
Determined by SDS-PAGE
Sterility 0.2 µm filtration
Production Purified from cell culture supernatant in an animal-free facility
Purification Protein G
RRID AB_1107766
Molecular Weight 150 kDa
Storage The antibody solution should be stored at the stock concentration at 4°C. Do not freeze.

Additional Formats

in vivo blocking of VEGF/VEGFR-2 signaling
Ding, X., et al. (2015). "Distinct functions of epidermal and myeloid-derived VEGF-A in skin tumorigenesis mediated by HPV8" Cancer Res 75(2): 330-343. PubMed

Beta human papillomaviruses (HPV) have been suspected to be carcinogenic in nonmelanoma skin cancers (NMSC), but the basis for potential viral contributions to these cancers is poorly understood. In particular, it is unresolved how HPV-infected keratinocytes escape cell-cycle control and whether their cross-talk with immune cells is critical for tumorigenesis. In nonviral preclinical models, the angiogenic cytokine VEGF-A has been identified as a critical regulator of NMSC. In this study, we dissected the contribution of epidermal versus myeloid cell-derived VEGF-A in HPV-mediated skin cancer by interbreeding an HPV8 transgenic mouse model with a conditional disruption of VEGF-A restricted to either epidermal or myeloid cells. Although only epidermal-derived VEGF-A was essential for initiation of skin tumor development, both spontaneously and UV-light triggered, both epidermal and myeloid cell-derived VEGF-A contributed to regeneration-induced tumorigenesis upon HPV8 overexpression, partly not only through a paracrine effect on endothelial cells, but also most probably through an additional autocrine effect on epidermal cells. Our findings offer new mechanistic insights into distinct functions of epidermal versus myeloid cell-derived VEGF-A during HPV-mediated tumorigenesis, with possible implications for preventing this disease.

in vivo blocking of VEGF/VEGFR-2 signaling
Lee, H. J., et al. (2015). "Inhibition of vascular endothelial growth factor A and hypoxia-inducible factor 1alpha maximizes the effects of radiation in sarcoma mouse models through destruction of tumor vasculature" Int J Radiat Oncol Biol Phys 91(3): 621-630. PubMed

PURPOSE: To examine the addition of genetic or pharmacologic inhibition of hypoxia-inducible factor 1alpha (HIF-1alpha) to radiation therapy (RT) and vascular endothelial growth factor A (VEGF-A) inhibition (ie trimodality therapy) for soft-tissue sarcoma. METHODS AND MATERIALS: Hypoxia-inducible factor 1alpha was inhibited using short hairpin RNA or low metronomic doses of doxorubicin, which blocks HIF-1alpha binding to DNA. Trimodality therapy was examined in a mouse xenograft model and a genetically engineered mouse model of sarcoma, as well as in vitro in tumor endothelial cells (ECs) and 4 sarcoma cell lines. RESULTS: In both mouse models, any monotherapy or bimodality therapy resulted in tumor growth beyond 250 mm(3) within the 12-day treatment period, but trimodality therapy with RT, VEGF-A inhibition, and HIF-1alpha inhibition kept tumors at <250 mm(3) for up to 30 days. Trimodality therapy on tumors reduced HIF-1alpha activity as measured by expression of nuclear HIF-1alpha by 87% to 95% compared with RT alone, and cytoplasmic carbonic anhydrase 9 by 79% to 82%. Trimodality therapy also increased EC-specific apoptosis 2- to 4-fold more than RT alone and reduced microvessel density by 75% to 82%. When tumor ECs were treated in vitro with trimodality therapy under hypoxia, there were significant decreases in proliferation and colony formation and increases in DNA damage (as measured by Comet assay and gammaH2AX expression) and apoptosis (as measured by cleaved caspase 3 expression). Trimodality therapy had much less pronounced effects when 4 sarcoma cell lines were examined in these same assays. CONCLUSIONS: Inhibition of HIF-1alpha is highly effective when combined with RT and VEGF-A inhibition in blocking sarcoma growth by maximizing DNA damage and apoptosis in tumor ECs, leading to loss of tumor vasculature.

in vivo blocking of VEGF/VEGFR-2 signaling
Arulanandam, R., et al. (2015). "VEGF-Mediated Induction of PRD1-BF1/Blimp1 Expression Sensitizes Tumor Vasculature to Oncolytic Virus Infection" Cancer Cell 28(2): 210-224. PubMed

Oncolytic viruses designed to attack malignant cells can in addition infect and destroy tumor vascular endothelial cells. We show here that this expanded tropism of oncolytic vaccinia virus to the endothelial compartment is a consequence of VEGF-mediated suppression of the intrinsic antiviral response. VEGF/VEGFR2 signaling through Erk1/2 and Stat3 leads to upregulation, nuclear localization, and activation of the transcription repressor PRD1-BF1/Blimp1. PRD1-BF1 does not contribute to the mitogenic effects of VEGF, but directly represses genes involved in type I interferon (IFN)-mediated antiviral signaling. In vivo suppression of VEGF signaling diminishes PRD1-BF1/Blimp1 expression in tumor vasculature and inhibits intravenously administered oncolytic vaccinia delivery to and consequent spread within the tumor.

in vivo blocking of VEGF/VEGFR-2 signaling, in vitro blocking of VEGFR signaling
Larrayoz, M., et al. (2014). "Contrasting responses of non-small cell lung cancer to antiangiogenic therapies depend on histological subtype" EMBO Mol Med 6(4): 539-550. PubMed

The vascular endothelial growth factor (VEGF) pathway is a clinically validated antiangiogenic target for non-small cell lung cancer (NSCLC). However, some contradictory results have been reported on the biological effects of antiangiogenic drugs. In order to evaluate the efficacy of these drugs in NSCLC histological subtypes, we analyzed the anticancer effect of two anti-VEGFR2 therapies (sunitinib and DC101) in chemically induced mouse models and tumorgrafts of lung adenocarcinoma (ADC) and squamous cell carcinoma (SCC). Antiangiogenic treatments induced vascular trimming in both histological subtypes. In ADC tumors, vascular trimming was accompanied by tumor stabilization. In contrast, in SCC tumors, antiangiogenic therapy was associated with disease progression and induction of tumor proliferation. Moreover, in SCC, anti-VEGFR2 therapies increased the expression of stem cell markers such as aldehyde dehydrogenase 1A1, CD133, and CD15, independently of intratumoral hypoxia. In vitro studies with ADC cell lines revealed that antiangiogenic treatments reduced pAKT and pERK signaling and inhibited proliferation, while in SCC-derived cell lines the same treatments increased pAKT and pERK, and induced survival. In conclusion, this study evaluates for the first time the effect of antiangiogenic drugs in lung SCC murine models in vivo and sheds light on the contradictory results of antiangiogenic therapies in NSCLC.

in vivo blocking of VEGF/VEGFR-2 signaling
Kizhatil, K., et al. (2014). "Schlemm’s canal is a unique vessel with a combination of blood vascular and lymphatic phenotypes that forms by a novel developmental process" PLoS Biol 12(7): e1001912. PubMed

Schlemm’s canal (SC) plays central roles in ocular physiology. These roles depend on the molecular phenotypes of SC endothelial cells (SECs). Both the specific phenotype of SECs and development of SC remain poorly defined. To allow a modern and extensive analysis of SC and its origins, we developed a new whole-mount procedure to visualize its development in the context of surrounding tissues. We then applied genetic lineage tracing, specific-fluorescent reporter genes, immunofluorescence, high-resolution confocal microscopy, and three-dimensional (3D) rendering to study SC. Using these techniques, we show that SECs have a unique phenotype that is a blend of both blood and lymphatic endothelial cell phenotypes. By analyzing whole mounts of postnatal mouse eyes progressively to adulthood, we show that SC develops from blood vessels through a newly discovered process that we name “canalogenesis.” Functional inhibition of KDR (VEGFR2), a critical receptor in initiating angiogenesis, shows that this receptor is required during canalogenesis. Unlike angiogenesis and similar to stages of vasculogenesis, during canalogenesis tip cells divide and form branched chains prior to vessel formation. Differing from both angiogenesis and vasculogenesis, during canalogenesis SECs express Prox1, a master regulator of lymphangiogenesis and lymphatic phenotypes. Thus, SC development resembles a blend of vascular developmental programs. These advances define SC as a unique vessel with a combination of blood vascular and lymphatic phenotypes. They are important for dissecting its functions that are essential for ocular health and normal vision.

in vivo blocking of VEGF/VEGFR-2 signaling
Villalta, S. A., et al. (2013). "Inhibition of VEGFR-2 reverses type 1 diabetes in NOD mice by abrogating insulitis and restoring islet function" Diabetes 62(8): 2870-2878. PubMed

The dysregulation of receptor tyrosine kinases (RTKs) in multiple cell types during chronic inflammation is indicative of their pathogenic role in autoimmune diseases. Among the many RTKs, vascular endothelial growth factor receptor (VEGFR) stands out for its multiple effects on immunity, vascularization, and cell migration. Herein, we examined whether VEGFR participated in the pathogenesis of type 1 diabetes (T1D) in nonobese diabetic (NOD) mice. We found that RTK inhibitors (RTKIs) and VEGF or VEGFR-2 antibodies reversed diabetes when administered at the onset of hyperglycemia. Increased VEGF expression promoted islet vascular remodeling in NOD mice, and inhibition of VEGFR activity with RTKIs abrogated the increase in islet vascularity, impairing T-cell migration into the islet and improving glucose control. Metabolic studies confirmed that RTKIs worked by preserving islet function, as treated mice had improved glucose tolerance without affecting insulin sensitivity. Finally, examination of human pancreata from patients with T1D revealed that VEGFR-2 was confined to the islet vascularity, which was increased in inflamed islets. Collectively, this work reveals a previously unappreciated role for VEGFR-2 signaling in the pathogenesis of T1D by controlling T-cell accessibility to the pancreatic islets and highlights a novel application of VEGFR-2 antagonists for the therapeutic treatment of T1D.

in vivo blocking of VEGF/VEGFR-2 signaling
Chatterjee, S., et al. (2013). "Junctional adhesion molecule-A regulates vascular endothelial growth factor receptor-2 signaling-dependent mouse corneal wound healing" PLoS One 8(5): e63674. PubMed

Inflammation and angiogenesis are integral parts of wound healing. However, excessive and persistent wound-induced inflammation and angiogenesis in an avascular tissue such as the cornea may be associated with scarring and visual impairment. Junctional adhesion molecule A (Jam-A) is a tight junction protein that regulates leukocyte transmigration as well as fibroblast growth factor-2 (FGF-2)-induced angiogenesis. However its function in wound-induced inflammation and angiogenesis is still unknown. In this study, we report spontaneous corneal opacity in Jam-A deficient mice associated with inflammation, angiogenesis and the presence of myofibroblasts. Since wounds and/or corneal infections cause corneal opacities, we tested the role of Jam-A in wound-induced inflammation, angiogenesis and scarring by subjecting Jam-A deficient mice to full thickness corneal wounding. Analysis of these wounds demonstrated increased inflammation, angiogenesis, and increased number of myofibroblasts thereby indicating that Jam-A regulates the wound-healing response by controlling wound-induced inflammation, angiogenesis and scarring in the cornea. These effects were not due to inflammation alone since the inflammation-induced wound-healing response in Jam-A deficient mice was similar to wild type mice. In order to determine the molecular mechanism associated with the observed aberrant corneal wound healing in Jam-A deficient mice, we assessed the expression of the components of vascular endothelial growth factor A (VEGF-A)/vascular endothelial growth factor receptor- 2(VEGFR-2) signaling pathway. Interestingly, we observed increased levels of VEGF-A mRNA in Jam-A deficient eyes. We also observed nuclear localization of phosphorylated SMAD3 (pSMAD3) indicative of TGFbeta pathway activation in the Jam-A deficient eyes. Furthermore the increased wound-induced corneal inflammation, angiogenesis, and scarring in Jam-A deficient mice was attenuated by treatment with DC101, an anti-vascular endothelial growth factor receptor-2 (VEGFR-2) antibody. Our results suggest that in the absence of Jam-A, the VEGF-A/VEGFR-2 pathway is upregulated, thereby augmenting wound induced corneal inflammation, angiogenesis, and myofibroblast accumulation leading to scarring.

in vivo blocking of VEGF/VEGFR-2 signaling
Kim, Y. J., et al. (2013). "Overcoming evasive resistance from vascular endothelial growth factor a inhibition in sarcomas by genetic or pharmacologic targeting of hypoxia-inducible factor 1alpha" Int J Cancer 132(1): 29-41. PubMed

Increased levels of hypoxia and hypoxia-inducible factor 1alpha (HIF-1alpha) in human sarcomas correlate with tumor progression and radiation resistance. Prolonged antiangiogenic therapy of tumors not only delays tumor growth but may also increase hypoxia and HIF-1alpha activity. In our recent clinical trial, treatment with the vascular endothelial growth factor A (VEGF-A) antibody, bevacizumab, followed by a combination of bevacizumab and radiation led to near complete necrosis in nearly half of sarcomas. Gene Set Enrichment Analysis of microarrays from pretreatment biopsies found that the Gene Ontology category “Response to hypoxia” was upregulated in poor responders and that the hierarchical clustering based on 140 hypoxia-responsive genes reliably separated poor responders from good responders. The most commonly used chemotherapeutic drug for sarcomas, doxorubicin (Dox), was recently found to block HIF-1alpha binding to DNA at low metronomic doses. In four sarcoma cell lines, HIF-1alpha shRNA or Dox at low concentrations blocked HIF-1alpha induction of VEGF-A by 84-97% and carbonic anhydrase 9 by 83-93%. HT1080 sarcoma xenografts had increased hypoxia and/or HIF-1alpha activity with increasing tumor size and with anti-VEGF receptor antibody (DC101) treatment. Combining DC101 with HIF-1alpha shRNA or metronomic Dox had a synergistic effect in suppressing growth of HT1080 xenografts, at least in part via induction of tumor endothelial cell apoptosis. In conclusion, sarcomas respond to increased hypoxia by expressing HIF-1alpha target genes that may promote resistance to antiangiogenic and other therapies. HIF-1alpha inhibition blocks this evasive resistance and augments destruction of the tumor vasculature.

in vivo blocking of VEGF/VEGFR-2 signaling
Kumar, V., et al. (2010). "Global lymphoid tissue remodeling during a viral infection is orchestrated by a B cell-lymphotoxin-dependent pathway" Blood 115(23): 4725-4733. PubMed

Adaptive immune responses are characterized by substantial restructuring of secondary lymphoid organs. The molecular and cellular factors responsible for virus-induced lymphoid remodeling are not well known to date. Here we applied optical projection tomography, a mesoscopic imaging technique, for a global analysis of the entire 3-dimensional structure of mouse peripheral lymph nodes (PLNs), focusing on B-cell areas and high endothelial venule (HEV) networks. Structural homeostasis of PLNs was characterized by a strict correlation between total PLN volume, B-cell volume, B-cell follicle number, and HEV length. After infection with lymphocytic choriomeningitis virus, we observed a substantial, lymphotoxin (LT) beta-receptor-dependent reorganization of the PLN microarchitecture, in which an initial B-cell influx was followed by 3-fold increases in PLN volume and HEV network length on day 8 after infection. Adoptive transfer experiments revealed that virus-induced PLN and HEV network remodeling required LTalpha(1)beta(2)-expressing B cells, whereas the inhibition of vascular endothelial growth factor-A signaling pathways had no significant effect on PLN expansion. In summary, lymphocytic choriomeningitis virus-induced PLN growth depends on a vascular endothelial growth factor-A-independent, LT- and B cell-dependent morphogenic pathway, as revealed by an in-depth mesoscopic analysis of the global PLN structure.

in vivo blocking of VEGF/VEGFR-2 signaling
Kilarski, W. W., et al. (2009). "Biomechanical regulation of blood vessel growth during tissue vascularization" Nat Med 15(6): 657-664. PubMed

Formation of new vessels in granulation tissue during wound healing has been assumed to occur solely through sprouting angiogenesis. In contrast, we show here that neovascularization can be accomplished by nonangiogenic expansion of preexisting vessels. Using neovascularization models based on the chick chorioallantoic membrane and the healing mouse cornea, we found that tissue tension generated by activated fibroblasts or myofibroblasts during wound contraction mediated and directed translocation of the vasculature. These mechanical forces pulled vessels from the preexisting vascular bed as vascular loops with functional circulation that expanded as an integral part of the growing granulation tissue through vessel enlargement and elongation. Blockade of vascular endothelial growth factor receptor-2 confirmed that biomechanical forces were sufficient to mediate the initial vascular growth independently of endothelial sprouting or proliferation. The neovascular network was further remodeled by splitting, sprouting and regression of individual vessels. This model explains the rapid appearance of large functional vessels in granulation tissue during wound healing.

    • Cancer Research
    • ,
    Antioxidants stimulate BACH1-dependent tumor angiogenesis.

    In The Journal of Clinical Investigation on 16 October 2023 by Wang, T., Dong, Y., et al.

    PubMed

    Lung cancer progression relies on angiogenesis, which is a response to hypoxia typically coordinated by hypoxia-inducible transcription factors (HIFs), but growing evidence indicates that transcriptional programs beyond HIFs control tumor angiogenesis. Here, we show that the redox-sensitive transcription factor BTB and CNC homology 1 (BACH1) controls the transcription of a broad range of angiogenesis genes. BACH1 is stabilized by lowering ROS levels; consequently, angiogenesis gene expression in lung cancer cells, tumor organoids, and xenograft tumors increased substantially following administration of vitamins C and E and N-acetylcysteine in a BACH1-dependent fashion under normoxia. Moreover, angiogenesis gene expression increased in endogenous BACH1-overexpressing cells and decreased in BACH1-knockout cells in the absence of antioxidants. BACH1 levels also increased upon hypoxia and following administration of prolyl hydroxylase inhibitors in both HIF1A-knockout and WT cells. BACH1 was found to be a transcriptional target of HIF1α, but BACH1's ability to stimulate angiogenesis gene expression was HIF1α independent. Antioxidants increased tumor vascularity in vivo in a BACH1-dependent fashion, and overexpressing BACH1 rendered tumors sensitive to antiangiogenesis therapy. BACH1 expression in tumor sections from patients with lung cancer correlated with angiogenesis gene and protein expression. We conclude that BACH1 is an oxygen- and redox-sensitive angiogenesis transcription factor.

    • Cancer Research
    • ,
    • In Vivo
    • ,
    • Mus musculus (House mouse)
    THBS1-producing tumor-infiltrating monocyte-like cells contribute to immunosuppression and metastasis in colorectal cancer.

    In Nature Communications on 25 September 2023 by Omatsu, M., Nakanishi, Y., et al.

    PubMed

    Mesenchymal activation, characterized by dense stromal infiltration of immune and mesenchymal cells, fuels the aggressiveness of colorectal cancers (CRC), driving progression and metastasis. Targetable molecules in the tumor microenvironment (TME) need to be identified to improve the outcome in CRC patients with this aggressive phenotype. This study reports a positive link between high thrombospondin-1 (THBS1) expression and mesenchymal characteristics, immunosuppression, and unfavorable CRC prognosis. Bone marrow-derived monocyte-like cells recruited by CXCL12 are the primary source of THBS1, which contributes to the development of metastasis by inducing cytotoxic T-cell exhaustion and impairing vascularization. Furthermore, in orthotopically generated CRC models in male mice, THBS1 loss in the TME renders tumors partially sensitive to immune checkpoint inhibitors and anti-cancer drugs. Our study establishes THBS1 as a potential biomarker for identifying mesenchymal CRC and as a critical suppressor of antitumor immunity that contributes to the progression of this malignancy with a poor prognosis. © 2023. Springer Nature Limited.

    • Cancer Research
    • ,
    • Cardiovascular biology
    • ,
    • Mus musculus (House mouse)
    Optical blood-brain-tumor barrier modulation expands therapeutic options for glioblastoma treatment.

    In Nature Communications on 15 August 2023 by Cai, Q., Li, X., et al.

    PubMed

    The treatment of glioblastoma has limited clinical progress over the past decade, partly due to the lack of effective drug delivery strategies across the blood-brain-tumor barrier. Moreover, discrepancies between preclinical and clinical outcomes demand a reliable translational platform that can precisely recapitulate the characteristics of human glioblastoma. Here we analyze the intratumoral blood-brain-tumor barrier heterogeneity in human glioblastoma and characterize two genetically engineered models in female mice that recapitulate two important glioma phenotypes, including the diffusely infiltrative tumor margin and angiogenic core. We show that pulsed laser excitation of vascular-targeted gold nanoparticles non-invasively and reversibly modulates the blood-brain-tumor barrier permeability (optoBBTB) and enhances the delivery of paclitaxel in these two models. The treatment reduces the tumor volume by 6 and 2.4-fold and prolongs the survival by 50% and 33%, respectively. Since paclitaxel does not penetrate the blood-brain-tumor barrier and is abandoned for glioblastoma treatment following its failure in early-phase clinical trials, our results raise the possibility of reevaluating a number of potent anticancer drugs by combining them with strategies to increase blood-brain-tumor barrier permeability. Our study reveals that optoBBTB significantly improves therapeutic delivery and has the potential to facilitate future drug evaluation for cancers in the central nervous system. © 2023. Springer Nature Limited.

    • Cancer Research
    • ,
    • Immunology and Microbiology
    Angiogenic inhibitor pre-administration improves the therapeutic effects of immunotherapy.

    In Cancer Medicine on 1 April 2023 by Sato, M., Maishi, N., et al.

    PubMed

    In lung cancer, immune checkpoint inhibitors (ICIs) are often inadequate for tumor growth inhibition. Angiogenic inhibitors (AIs) are required to normalize tumor vasculature for improved immune cell infiltration. However, in clinical practice, ICIs and cytotoxic antineoplastic agents are simultaneously administered with an AI when tumor vessels are abnormal. Therefore, we examined the effects of pre-administering an AI for lung cancer immunotherapy in a mouse lung cancer model. Using DC101, an anti-vascular endothelial growth factor receptor 2 (VEGFR2) monoclonal antibody, a murine subcutaneous Lewis lung cancer (LLC) model was used to determine the timing of vascular normalization. Microvessel density (MVD), pericyte coverage, tissue hypoxia, and CD8-positive cell infiltration were analyzed. The effects of an ICI and paclitaxel after DC101 pre-administration were investigated. On Day 3, increased pericyte coverage and alleviated tumor hypoxia represented the highest vascular normalization. CD8+ T-cell infiltration was also highest on Day 3. When combined with an ICI, DC101 pre-administration significantly reduced PD-L1 expression. When combined with an ICI and paclitaxel, only DC101 pre-administration significantly inhibited tumor growth, but simultaneous administration did not. AI pre-administration, and not simultaneous administration, may increase the therapeutic effects of ICIs due to improved immune cell infiltration. © 2023 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

    • Mus musculus (House mouse)
    • ,
    • Immunology and Microbiology
    • ,
    • Cell Biology
    • ,
    • Biochemistry and Molecular biology
    PHGDH-mediated endothelial metabolism drives glioblastoma resistance to chimeric antigen receptor T cell immunotherapy.

    In Cell Metabolism on 7 March 2023 by Zhang, D., Li, A. M., et al.

    PubMed

    The efficacy of immunotherapy is limited by the paucity of T cells delivered and infiltrated into the tumors through aberrant tumor vasculature. Here, we report that phosphoglycerate dehydrogenase (PHGDH)-mediated endothelial cell (EC) metabolism fuels the formation of a hypoxic and immune-hostile vascular microenvironment, driving glioblastoma (GBM) resistance to chimeric antigen receptor (CAR)-T cell immunotherapy. Our metabolome and transcriptome analyses of human and mouse GBM tumors identify that PHGDH expression and serine metabolism are preferentially altered in tumor ECs. Tumor microenvironmental cues induce ATF4-mediated PHGDH expression in ECs, triggering a redox-dependent mechanism that regulates endothelial glycolysis and leads to EC overgrowth. Genetic PHGDH ablation in ECs prunes over-sprouting vasculature, abrogates intratumoral hypoxia, and improves T cell infiltration into the tumors. PHGDH inhibition activates anti-tumor T cell immunity and sensitizes GBM to CAR T therapy. Thus, reprogramming endothelial metabolism by targeting PHGDH may offer a unique opportunity to improve T cell-based immunotherapy. Copyright © 2023 Elsevier Inc. All rights reserved.

    • Cancer Research
    • ,
    • Endocrinology and Physiology
    • ,
    • Mus musculus (House mouse)
    “Tumor Explants Elucidate a Cascade of Paracrine SHH, WNT, and VEGF Signals Driving Pancreatic Cancer Angiosuppression”

    Preprint on BioRxiv : the Preprint Server for Biology on 2 March 2023 by Hasselluhn, M. C., Decker-Farrell, A. R., et al.

    PubMed

    The sparse vascularity of Pancreatic Ductal Adenocarcinoma (PDAC) presents a mystery: what prevents this aggressive malignancy from undergoing neoangiogenesis to counteract hypoxia and better support growth? An incidental finding from prior work on paracrine communication between malignant PDAC cells and fibroblasts revealed that inhibition of the Hedgehog (HH) pathway partially relieved angiosuppression, increasing tumor vascularity through unknown mechanisms. Initial efforts to study this phenotype were hindered by difficulties replicating the complex interactions of multiple cell types in vitro . Here we identify a cascade of paracrine signals between multiple cell types that act sequentially to suppress angiogenesis in PDAC. Malignant epithelial cells promote HH signaling in fibroblasts, leading to inhibition of WNT signaling in fibroblasts and epithelial cells, thereby limiting VEGFR2-dependent activation of endothelial hypersprouting. This cascade was elucidated using human and murine PDAC explant models, which effectively retain the complex cellular interactions of native tumor tissues.

    • Cancer Research
    • ,
    • Immunology and Microbiology
    • ,
    • Mus musculus (House mouse)
    Targeting tumor vasculature to improve antitumor activity of T cells armed ex vivo with T cell engaging bispecific antibody.

    In Journal for Immunotherapy of Cancer on 1 March 2023 by Park, J. A., Espinosa-Cotton, M., et al.

    PubMed

    Success of T cell immunotherapy hinges on the tumor microenvironment (TME), and abnormal tumor vasculature is a hallmark of most solid tumors and associated with immune evasion. The efficacy of T cell engaging bispecific antibody (BsAb) treatment relies on the successful trafficking and cytolytic activity of T cells in solid tumors. Normalization of tumor vasculature using vascular endothelial growth factor (VEGF) blockades could improve efficacy of BsAb-based T cell immunotherapy. Anti-human VEGF (bevacizumab, BVZ) or anti-mouse VEGFR2 antibody (DC101) was used as VEGF blockade, and ex vivo armed T cells (EATs) carrying anti-GD2, anti-HER2, or anti-glypican3 (GPC3) IgG-(L)-scFv platformed BsAb were used. BsAb-driven intratumoral T cell infiltration and in vivo antitumor response were evaluated using cancer cell line-derived xenografts (CDXs) or patient-derived xenografts (PDXs) carried out in BALB-Rag2 -/-IL-2R-γc-KO (BRG) mice. VEGF expression on human cancer cell lines was analyzed by flow cytometry, and VEGF levels in mouse serum were measured using VEGF Quantikine ELISA Kit. Tumor infiltrating lymphocytes (TILs) were evaluated using flow cytometry and by bioluminescence; both TILs and tumor vasculature were studied using immunohistochemistry. VEGF expression on cancer cell lines increased with seeding density in vitro. BVZ significantly reduced serum VEGF levels in mice. BVZ or DC101 increased high endothelial venules (HEVs) in the TME and substantially enhanced (2.1-8.1 fold) BsAb-driven T cell infiltration into neuroblastoma and osteosarcoma xenografts, which was preferential for CD8(+) TILs versus CD4(+) TILs, leading to superior antitumor effects in multiple CDX and PDX tumor models without added toxicities. VEGF blockade using specific antibodies against VEGF or VEGFR2 increased HEVs in the TME and cytotoxic CD8(+) TILs, significantly improving the therapeutic efficacy of EAT strategies in preclinical models, supporting the clinical investigation of VEGF blockades to further enhance BsAb-based T cell immunotherapies. © Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

    • FC/FACS
    • ,
    • Mus musculus (House mouse)
    • ,
    • Cancer Research
    • ,
    • Immunology and Microbiology
    Low-dose anti-VEGFR2 therapy promotes anti-tumor immunity in lung adenocarcinoma by down-regulating the expression of layilin on tumor-infiltrating CD8+T cells.

    In Cellular Oncology (Dordrecht) on 1 December 2022 by Yang, B., Deng, B., et al.

    PubMed

    Our study intended to explore how low-dose anti-angiogenic drugs affected anti-tumor immunity of tumor-infiltrating exhausted CD8+T cells and achieved better clinical response when combined with immunotherapy. We set out to find potential targets or predictive biomarker on CD8+T cells for immunotherapy. We tested different doses of anti-VEGFR2 antibody combined with anti-PD1 antibody to treat LUAD in vivo and analyzed tumor-infiltrating CD8+T cells by flow cytometry. CD8+T cells overexpressing LAYN were co-cultured with LA795 cell lines to identify the function of LAYN in CD8+T cells. We also analyzed clinical samples from advanced LUAD patients treated with anti-angiogenesis therapy combined with immunotherapy. Low-dose anti-VEGFR2 antibody combined with anti-PD1 antibody treatment delayed tumor growth and prolonged the survival time of tumor-bearing mice. The number of tumor-infiltrating CD8+T cells was reduced and the expression of LAYN was down-regulated in tumor-infiltrating CD8+T cells in the low-dose anti-VEGFR2 combination group. It was found that LAYN inhibited the killing function of CD8+T cells. In patients with advanced LUAD who received anti-angiogenesis therapy combined with immunotherapy, the LAYN+CD8+T cell subpopulation in good responders was significantly higher than that in poor responders. Furthermore, we demonstrated the expression of LAYN was regulated by upstream transcription factor NR4A1. Low-dose anti-VEGFR2 antibody combined with anti-PD1 antibody therapy promoted anti-tumor immunity and the downregulation of LAYN in tumor-infiltrating CD8+T cells played an important role in this process. These findings had implications for improving the efficacy of immune checkpoint blockade therapy and further optimized clinical treatment guidelines in advanced LUAD. © 2022. The Author(s).

    • Mus musculus (House mouse)
    • ,
    • Cancer Research
    • ,
    • Cell Biology
    • ,
    • Immunology and Microbiology
    Cancer cell autophagy, reprogrammed macrophages, and remodeled vasculature in glioblastoma triggers tumor immunity.

    In Cancer Cell on 10 October 2022 by Chryplewicz, A., Scotton, J., et al.

    PubMed

    Glioblastoma (GBM) is poorly responsive to therapy and invariably lethal. One conceivable strategy to circumvent this intractability is to co-target distinctive mechanistic components of the disease, aiming to concomitantly disrupt multiple capabilities required for tumor progression and therapeutic resistance. We assessed this concept by combining vascular endothelial growth factor (VEGF) pathway inhibitors that remodel the tumor vasculature with the tricyclic antidepressant imipramine, which enhances autophagy in GBM cancer cells and unexpectedly reprograms immunosuppressive tumor-associated macrophages via inhibition of histamine receptor signaling to become immunostimulatory. While neither drug is efficacious as monotherapy, the combination of imipramine with VEGF pathway inhibitors orchestrates the infiltration and activation of CD8 and CD4 T cells, producing significant therapeutic benefit in several GBM mouse models. Inclusion up front of immune-checkpoint blockade with anti-programmed death-ligand 1 (PD-L1) in eventually relapsing tumors markedly extends survival benefit. The results illustrate the potential of mechanism-guided therapeutic co-targeting of disparate biological vulnerabilities in the tumor microenvironment.Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.

    • Cancer Research
    Nucleolin Therapeutic Targeting Decreases Pancreatic Cancer Immunosuppression.

    In Cancers on 31 August 2022 by Ponzo, M., Debesset, A., et al.

    PubMed

    The pancreatic ductal adenocarcinoma (PDAC) microenvironment is highly fibrotic and hypoxic, with poor immune cell infiltration. Recently, we showed that nucleolin (NCL) inhibition normalizes tumour vessels and impairs PDAC growth. Immunocompetent mouse models of PDAC were treated by the pseudopeptide N6L,amp;nbsp;which selectively inhibits NCL. Tumour-infiltrating immune cells and changes in the tumour microenvironment were analysed. N6L reduced the proportion of regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) and increased tumour-infiltrated T lymphocytes (TILs) with an activated phenotype. Low-dose anti-VEGFR2 treatment normalized PDAC vessels but did not modulate the immune suppressive microenvironment. RNAseq analysis of N6L-treated PDAC tumours revealed a reduction of cancer-associated fibroblast (CAF) expansion in vivo and in vitro. Notably, N6L treatment decreased IL-6 levels both in tumour tissues and in serum. Treating mPDAC by an antibody blocking IL-6 reduced the proportion of Tregs and MDSCs and increased the amount of TILs, thus mimicking the effects of N6L. These results demonstrate that NCL inhibition blocks the amplification of lymphoid and myeloid immunosuppressive cells and promotes T cell activation in PDAC through a new mechanism of action dependent on the direct inhibition of the tumoral stroma.

    • Cancer Research
    • ,
    • Immunology and Microbiology
    Low-dose anti-VEGFR2 therapy promotes anti-tumor immunity in lung adenocarcinoma by down-regulating the expression of layilin on tumor-infiltrating CD8+T cells

    Preprint on Research Square on 18 May 2022 by Yang, B., Deng, B., et al.

    PubMed

    h4>Purpose: /h4> Our study intended to explore how low-dose anti-angiogenic drugs affected anti-tumor immunity of tumor-infiltrating exhausted CD8 + T cells and achieved better clinical response when combined with immunotherapy. We set out to find potential targets or predictive biomarker on CD8 +\ T cells for immunotherapy. Methods We tested different doses of anti-VEGFR2 antibody combined with anti-PD1 antibody to treat LUAD in vivo and analyzed tumor-infiltrating CD8 + T cells by flow cytometry. CD8 + T cells overexpressing LAYN were co-cultured with LA795 cell lines to identify the function of LAYN in CD8 + T cells. We also analyzed clinical samples from advanced LUAD patients treated with anti-angiogenesis therapy combined with immunotherapy. Results Low-dose anti-VEGFR2 antibody combined with anti-PD1 antibody treatment delayed tumor growth and prolonged the survival time of tumor-bearing mice. The number of tumor-infiltrating CD8 + T cells was reduced and the expression of LAYN was down-regulated in tumor-infiltrating CD8 + T cells in the low-dose anti-VEGFR2 combination group. It was found that LAYN inhibited the killing function of CD8 + T cells. In patients with advanced LUAD who received anti-angiogenesis therapy combined with immunotherapy, the LAYN + CD8 + T cell subpopulation in good responders was significantly higher than that in poor responders. Furthermore, we demonstrated the expression of LAYN was regulated by upstream transcription factor NR4A1. Conclusion Low-dose anti-VEGFR2 antibody combined with anti-PD1 antibody therapy promoted anti-tumor immunity and the downregulation of LAYN in tumor-infiltrating CD8 + T cells played an important role in this process. These findings had implications for improving the efficacy of immune checkpoint blockade therapy and further optimized clinical treatment guidelines in advanced LUAD.

    • Cancer Research
    • ,
    • Cell Biology
    • ,
    • Mus musculus (House mouse)
    Increased alveolar epithelial TRAF6 via autophagy-dependent TRIM37 degradation mediates particulate matter-induced lung metastasis.

    In Autophagy on 1 May 2022 by Liu, J., Li, S., et al.

    PubMed

    Epidemiological and clinical studies have shown that exposure to particulate matter (PM) is associated with an increased incidence of lung cancer and metastasis. However, the underlying mechanism remains unclear. Here, we demonstrated the central role of PM-induced neutrophil recruitment in promoting lung cancer metastasis. We found that reactive oxygen species (ROS)-mediated alveolar epithelial macroautophagy/autophagy was essential for initiating neutrophil chemotaxis and pre-metastatic niche formation in the lungs in response to PM exposure. During PM-induced autophagy, the E3 ubiquitin ligase TRIM37 was degraded and protected TRAF6 from proteasomal degradation in lung epithelial cells, which promoted the NFKB-dependent production of chemokines to recruit neutrophils. Importantly, ROS blockade, autophagy inhibition or TRAF6 knockdown abolished PM-induced neutrophil recruitment and lung metastasis enhancement. Our study indicates that host lung epithelial cells and neutrophils coordinate to promote cancer metastasis to the lungs in response to PM exposure and provides ideal therapeutic targets for metastatic progression.Abbreviations: ACTA2/α-SMA: actin alpha 2, smooth muscle, aorta; ATII: alveolar type II; Cho-Traf6 siRNA: 5'-cholesterol-Traf6 siRNA; EMT: epithelial-mesenchymal transition; HBE: human bronchial epithelial; HCQ: hydroxychloroquine; MAPK: mitogen-activated protein kinase; NAC: N-acetyl-L-cysteine; NFKB: nuclear factor of kappa light polypeptide gene enhancer in B cells; NS: normal saline; PM: particulate matter; ROS: reactive oxygen species; TRAF6: TNF receptor-associated factor 6; TRIM37: tripartite motif-containing 37.

    Perivascular tenascin C triggers sequential activation of macrophages and endothelial cells to generate a pro-metastatic vascular niche in the lungs.

    In Nature Cancer on 1 April 2022 by Hongu, T., Pein, M., et al.

    PubMed

    Disseminated cancer cells frequently lodge near vasculature in secondary organs. However, our understanding of the cellular crosstalk invoked at perivascular sites is still rudimentary. Here, we identify intercellular machinery governing formation of a pro-metastatic vascular niche during breast cancer colonization in the lung. We show that specific secreted factors, induced in metastasis-associated endothelial cells (ECs), promote metastasis in mice by enhancing stem cell properties and the viability of cancer cells. Perivascular macrophages, activated via tenascin C (TNC) stimulation of Toll-like receptor 4 (TLR4), were shown to be crucial in niche activation by secreting nitric oxide (NO) and tumor necrosis factor (TNF) to induce EC-mediated production of niche components. Notably, this mechanism was independent of vascular endothelial growth factor (VEGF), a key regulator of EC behavior and angiogenesis. However, targeting both macrophage-mediated vascular niche activation and VEGF-regulated angiogenesis resulted in added potency to curb lung metastasis in mice. Together, our findings provide mechanistic insights into the formation of vascular niches in metastasis. © 2022. The Author(s).

    • Cancer Research
    • ,
    • Genetics
    • ,
    • Immunology and Microbiology
    Combining p53 mRNA nanotherapy with immune checkpoint blockade reprograms the immune microenvironment for effective cancer therapy.

    In Nature Communications on 9 February 2022 by Xiao, Y., Chen, J., et al.

    PubMed

    Immunotherapy with immune checkpoint blockade (ICB) has shown limited benefits in hepatocellular carcinoma (HCC) and other cancers, mediated in part by the immunosuppressive tumor microenvironment (TME). As p53 loss of function may play a role in immunosuppression, we herein examine the effects of restoring p53 expression on the immune TME and ICB efficacy. We develop and optimize a CXCR4-targeted mRNA nanoparticle platform to effectively induce p53 expression in HCC models. Using p53-null orthotopic and ectopic models of murine HCC, we find that combining CXCR4-targeted p53 mRNA nanoparticles with anti-PD-1 therapy effectively induces global reprogramming of cellular and molecular components of the immune TME. This effect results in improved anti-tumor effects compared to anti-PD-1 therapy or therapeutic p53 expression alone. Thus, our findings demonstrate the reversal of immunosuppression in HCC by a p53 mRNA nanomedicine when combined with ICB and support the implementation of this strategy for cancer treatment. © 2022. The Author(s).

    • Mus musculus (House mouse)
    Low-flow intussusception and metastable VEGFR2 signaling launch angiogenesis in ischemic muscle.

    In Science Advances on 26 November 2021 by Arpino, J. M., Yin, H., et al.

    PubMed

    Efforts to promote sprouting angiogenesis in skeletal muscles of individuals with peripheral artery disease have not been clinically successful. We discovered that, contrary to the prevailing view, angiogenesis following ischemic muscle injury in mice was not driven by endothelial sprouting. Instead, real-time imaging revealed the emergence of wide-caliber, primordial conduits with ultralow flow that rapidly transformed into a hierarchical neocirculation by transluminal bridging and intussusception. This process was accelerated by inhibiting vascular endothelial growth factor receptor-2 (VEGFR2). We probed this response by developing the first live-cell model of transluminal endothelial bridging using microfluidics. Endothelial cells subjected to ultralow shear stress could reposition inside the flowing lumen as pillars. Moreover, the low-flow lumen proved to be a privileged location for endothelial cells with reduced VEGFR2 signaling capacity, as VEGFR2 mechanosignals were boosted. These findings redefine regenerative angiogenesis in muscle as an intussusceptive process and uncover a basis for its launch.

    • In Vivo
    • ,
    • Mus musculus (House mouse)
    • ,
    • Cancer Research
    Reprogramming NK cells and macrophages via combined antibody and cytokine therapy primes tumors for elimination by checkpoint blockade.

    In Cell Reports on 23 November 2021 by Wang, C., Cui, A., et al.

    PubMed

    Treatments aiming to augment immune checkpoint blockade (ICB) in cancer often focus on T cell immunity, but innate immune cells may have important roles to play. Here, we demonstrate a single-dose combination treatment (termed AIP) using a pan-tumor-targeting antibody surrogate, half-life-extended interleukin-2 (IL-2), and anti-programmed cell death 1 (PD-1), which primes tumors to respond to subsequent ICB and promotes rejection of large established tumors in mice. Natural killer (NK) cells and macrophages activated by AIP treatment underwent transcriptional reprogramming; rapidly killed cancer cells; governed the recruitment of cross-presenting dendritic cells (DCs) and other leukocytes; and induced normalization of the tumor vasculature, facilitating further immune infiltration. Thus, innate cell-activating therapies can initiate critical steps leading to a self-sustaining cycle of T cell priming driven by ICB.Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.

    • Cancer Research
    • ,
    • Immunology and Microbiology
    "γδT Cell-IL17A-Neutrophil" Axis Drives Immunosuppression and Confers Breast Cancer Resistance to High-Dose Anti-VEGFR2 Therapy.

    In Frontiers in Immunology on 2 November 2021 by Zhang, Z., Yang, C., et al.

    PubMed

    Angiogenesis is an essential physiological process and hallmark of cancer. Currently, antiangiogenic therapy, mostly targeting the vascular endothelial growth factor (VEGF)/VEGFR2 signaling axis, is commonly used in the clinic for solid tumors. However, antiangiogenic therapies for breast cancer patients have produced limited survival benefits since cancer cells rapidly resistant to anti-VEGFR2 therapy. We applied the low-dose and high-dose VEGFR2 mAb or VEGFR2-tyrosine kinase inhibitor (TKI) agents in multiple breast cancer mouse models and found that low-dose VEGFR2 mAb or VEGFR2-TKI achieved good effects in controlling cancer progression, while high-dose treatment was not effective. To further investigate the mechanism involved in regulating the drug resistance, we found that high-dose anti-VEGFR2 treatment elicited IL17A expression in γδ T cells via VEGFR1-PI3K-AKT pathway activation and then promoted N2-like neutrophil polarization, thus inducing CD8+ T cell exhaustion to shape an immunosuppressive microenvironment. Combining anti-VEGFR2 therapy with immunotherapy such as IL17A, PD-1 or Ly-6G mAb therapy, which targeting the immunomodulatory axis of "γδT17 cells-N2 neutrophils" in vivo, showed promising therapeutic effects in breast cancer treatment. This study illustrates the potential mechanism of antiangiogenic therapy resistance in breast cancer and provides synergy treatment for cancer. Copyright © 2021 Zhang, Yang, Li, Zhu, Su, Zhai, Wang and Huang.

    • Endocrinology and Physiology
    • ,
    • Immunology and Microbiology
    Viral infection of the ovaries compromises pregnancy and reveals innate immune mechanisms protecting fertility.

    In Immunity on 13 July 2021 by Tomac, J., Mazor, M., et al.

    PubMed

    Viral infections during pregnancy are a considerable cause of adverse outcomes and birth defects, and the underlying mechanisms are poorly understood. Among those, cytomegalovirus (CMV) infection stands out as the most common intrauterine infection in humans, putatively causing early pregnancy loss. We employed murine CMV as a model to study the consequences of viral infection on pregnancy outcome and fertility maintenance. Even though pregnant mice successfully controlled CMV infection, we observed highly selective, strong infection of corpus luteum (CL) cells in their ovaries. High infection densities indicated complete failure of immune control in CL cells, resulting in progesterone insufficiency and pregnancy loss. An abundance of gap junctions, absence of vasculature, strong type I interferon (IFN) responses, and interaction of innate immune cells fully protected the ovarian follicles from viral infection. Our work provides fundamental insights into the effect of CMV infection on pregnancy loss and mechanisms protecting fertility. Copyright © 2021 Elsevier Inc. All rights reserved.

    • Cancer Research
    • ,
    • Immunology and Microbiology
    • ,
    • In Vivo
    • ,
    • Mus musculus (House mouse)
    IL1β Promotes Immune Suppression in the Tumor Microenvironment Independent of the Inflammasome and Gasdermin D.

    In Cancer Immunology Research on 1 March 2021 by Kiss, M., Vande Walle, L., et al.

    PubMed

    IL1β is a central mediator of inflammation. Secretion of IL1β typically requires proteolytic maturation by the inflammasome and formation of membrane pores by gasdermin D (GSDMD). Emerging evidence suggests an important role for IL1β in promoting cancer progression in patients, but the underlying mechanisms are ill-defined. Here, we have shown a key role for IL1β in driving tumor progression in two distinct mouse tumor models. Notably, activation of the inflammasome, caspase-8, as well as the pore-forming proteins GSDMD and mixed lineage kinase domain-like protein in the host were dispensable for the release of intratumoral bioactive IL1β. Inflammasome-independent IL1β release promoted systemic neutrophil expansion and fostered accumulation of T-cell-suppressive neutrophils in the tumor. Moreover, IL1β was essential for neutrophil infiltration triggered by antiangiogenic therapy, thereby contributing to treatment-induced immunosuppression. Deletion of IL1β allowed intratumoral accumulation of CD8+ effector T cells that subsequently activated tumor-associated macrophages. Depletion of either CD8+ T cells or macrophages abolished tumor growth inhibition in IL1β-deficient mice, demonstrating a crucial role for CD8+ T-cell-macrophage cross-talk in the antitumor immune response. Overall, these results support a tumor-promoting role for IL1β through establishing an immunosuppressive microenvironment and show that inflammasome activation is not essential for release of this cytokine in tumors. ©2020 American Association for Cancer Research.

    • Cancer Research
    • ,
    • Immunology and Microbiology
    DKK2 blockage-mediated immunotherapy enhances anti-angiogenic therapy of Kras mutated colorectal cancer.

    In Biomedicine Pharmacotherapy = Biomédecine Pharmacothérapie on 1 July 2020 by Hu, J., Wang, Z., et al.

    PubMed

    There are limited options for targeted therapies for colorectal cancer (CRC). Anti-EGFR therapy is limited to CRC without KRAS mutations. Even worse, most of CRC are refractory to currently immune checkpoint blockade. DKK2, which is upregulated in CRC, was recently found to suppress host immune responses, and its blockage effectively impeded tumor progression in benign genetic CRC models in our previous study. Here, our recent study demonstrated that in human CRC tumor samples expressing high levels of DKK2, DKK2 blockade caused stronger activation of tumor infiltrating CD8+ T cells in ex vivo culture. Intriguingly, we observed a correlation of high DKK2 expression with increased lymph node metastasis prevalence in these CRC patients as well. Furthermore, in a mouse genetic CRC model with mutations in APC and KRAS, which more closely mimics advanced human CRC, we confirmed the tumor inhibitory effect of DKK2 blockade, which significantly retarded tumor progression and extended survival, with increased immune effector cell activation and reduced angiogenesis. Based on this, we performed a combined administration of DKK2 blockade with sub-optimal anti-VEGFR treatment and observed a synergetic effect on suppressing tumor angiogenesis and progression, as well as extending survival, better than those of every single therapy. Thus, this study provides further evidence for the potential therapeutic application of DKK2 blockade in the clinical treatment of human CRC. Copyright © 2020 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

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