scholarly journals Amino acid transporter LAT1 in tumor-associated vascular endothelium promotes angiogenesis by regulating cell proliferation and VEGF-A-dependent mTORC1 activation

2020 ◽  
Vol 39 (1) ◽  
Author(s):  
Lili Quan ◽  
Ryuichi Ohgaki ◽  
Saori Hara ◽  
Suguru Okuda ◽  
Ling Wei ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Endothelial Cells ◽  
Amino Acid ◽  
Tumor Cells ◽  
Tumor Angiogenesis ◽  
Amino Acid Transporter ◽  
Mouse Tumor ◽  
Tumor Models ◽  
Mouse Tumor Models

Abstract Background Tumor angiogenesis is regarded as a rational anti-cancer target. The efficacy and indications of anti-angiogenic therapies in clinical practice, however, are relatively limited. Therefore, there still exists a demand for revealing the distinct characteristics of tumor endothelium that is crucial for the pathological angiogenesis. L-type amino acid transporter 1 (LAT1) is well known to be highly and broadly upregulated in tumor cells to support their growth and proliferation. In this study, we aimed to establish the upregulation of LAT1 as a novel general characteristic of tumor-associated endothelial cells as well, and to explore the functional relevance in tumor angiogenesis. Methods Expression of LAT1 in tumor-associated endothelial cells was immunohistologically investigated in human pancreatic ductal adenocarcinoma (PDA) and xenograft- and syngeneic mouse tumor models. The effects of pharmacological and genetic ablation of endothelial LAT1 were examined in aortic ring assay, Matrigel plug assay, and mouse tumor models. The effects of LAT1 inhibitors and gene knockdown on cell proliferation, regulation of translation, as well as on the VEGF-A-dependent angiogenic processes and intracellular signaling were investigated in in vitro by using human umbilical vein endothelial cells. Results LAT1 was highly expressed in vascular endothelial cells of human PDA but not in normal pancreas. Similarly, high endothelial LAT1 expression was observed in mouse tumor models. The angiogenesis in ex/in vivo assays was suppressed by abrogating the function or expression of LAT1. Tumor growth in mice was significantly impaired through the inhibition of angiogenesis by targeting endothelial LAT1. LAT1-mediated amino acid transport was fundamental to support endothelial cell proliferation and translation initiation in vitro. Furthermore, LAT1 was required for the VEGF-A-dependent migration, invasion, tube formation, and activation of mTORC1, suggesting a novel cross-talk between pro-angiogenic signaling and nutrient-sensing in endothelial cells. Conclusions These results demonstrate that the endothelial LAT1 is a novel key player in tumor angiogenesis, which regulates proliferation, translation, and pro-angiogenic VEGF-A signaling. This study furthermore indicates a new insight into the dual functioning of LAT1 in tumor progression both in tumor cells and stromal endothelium. Therapeutic inhibition of LAT1 may offer an ideal option to potentiate anti-angiogenic therapies.

Abstract 3071: Size-based isolation of circulating tumor cells (CTCs) in mouse tumor models

2014 ◽  
Author(s):  
Katarina Kolostova ◽  
Robert M. Hoffman ◽  
Ali Maawy ◽  
Yong Zhang ◽  
Vladimir Bobek
Keyword(s):  
Tumor Cells ◽  
Circulating Tumor Cells ◽  
Mouse Tumor ◽  
Tumor Models ◽  
Mouse Tumor Models

Carcinoembryonic Antigen (CEA) Regulates Tumor-Angiogenesis in Colon Carcinomas.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1897-1897
Author(s):  
Kira Braemswig ◽  
Marina Poettler ◽  
Wazlawa Kalinowska ◽  
Christoph Zielinski ◽  
Gerald W Prager
Keyword(s):  
Cell Proliferation ◽  
Endothelial Cells ◽  
Endothelial Cell ◽  
Tumor Angiogenesis ◽  
Endothelial Cell Proliferation ◽  
Erk Phosphorylation ◽  
Dose Dependent Increase ◽  
Dose Dependent

Abstract Human carcinoembryonic antigen (CEA) is a cell surface adhesion molecule member of the Immunoglobulin Superfamily (IgSF). Aberrant upregulation and secretion of soluble CEA is a common feature found in a wide variety of human cancers such as colon, breast and lung. Previous in vitro and in vivo results have demonstrated that CEA can affect tumor cell behavior including the inhibition of cell differentiation and apoptosis. However, any functional effects on angiogenic endothelial cell behavior are so far unknown. In the present work we found that in endothelial cells exogenous CEA led to a time and dose dependent increase in ERK phosphorylation, which was inhibited by the specific MEK inhibitor U0126. Thereby, the observed CEA effect was comparable in time and intense with the canonical angiogenic growth factor VEGF. The CEA-induced ERK phosphorylation was not affected by the blockage of VEGFR-2 / flk-1 using a specific inhibiting peptide (CBO-P11), which indicates a VEGF-independent mechanism. Furthermore, co-stimulation of endothelial cells with VEGF and CEA shows synergistic effects on ERK phosphorylation. While in endothelial cells no endogenous expression of CEA is detected, its putative receptor, the CEA receptor (CEAR), is highly expressed as shown by immunohistochemical staining of paraffin-embedded colon carcinoma sections as well as in biochemical analyses. When an activating antibody against CEAR was used, CEA-induced ERK phosphorylation was mimicked, while downregulation of CEAR by siRNA diminished CEA-induced signal transduction, significantly. To test a biological relevance of our findings, we first measured endothelial cell proliferation: CEA led to a dose dependent increase in endothelial cell proliferation in vitro, which again revealed a synergistic effect with VEGF. Thereby, CEA-induced endothelial cell proliferation was again independent of VEGFR-2 / flk-1. A biological role of CEA in tumor-angiogenesis was reflected by an in vivo model using CEA Mimotope immunized BALB/c mice, which were transplanted with MethA/CEA overexpressing tumor cells. Immunohistological analyses of these tumors revealed a significantly reduced vascular density, which was accompanied with diminished tumor growth. Our data provide first evidence of CEA as a novel pro-angiogenic activator of endothelial cells, which results in an increase in endothelial cell proliferation, independent of VEGFR-2. Furthermore, by targeting CEA in an in vivo mouse model, tumor-angiogenesis was markley reduced, indicating a potential therapeutic target in cancer.

Heparanase expression of glioma in human and animal models

2010 ◽  
Vol 113 (2) ◽  
pp. 261-269 ◽  
Author(s):  
Xin Hong ◽  
Kevin K. Nelson ◽  
Ana C. deCarvalho ◽  
Steven N. Kalkanis
Keyword(s):  
Cell Proliferation ◽  
Endothelial Cells ◽  
Animal Models ◽  
Tumor Cells ◽  
Cell Types ◽  
Human Glioma ◽  
Ki 67 ◽  
Western Blot Assay ◽  
Significant Difference

Object Mammalian heparanase has been shown to function in tumor progression, invasion, and angiogenesis. However, heparanase expression in gliomas has not been well analyzed. To clarify its expression in gliomas, human glioma tissues and glioma animal models were investigated. Methods The expression of heparanase mRNA was determined in 33 resected human glioma tissues by semiquantitative real-time polymerase chain reaction. Heparanase expression was verified with a Western blot assay and immunohistochemistry (IHC) staining. Primary neurospheres from human glioblastoma multiforme (GBM) were developed in vitro. Heparanase expression in murine astrocytoma and human primary neurosphere animal models was examined using IHC. Results The authors found that heparanase mRNA is greatly increased in gliomas including oligodendroglioma (9 samples), anaplastic astrocytoma (11 samples), and GBM (13 samples) as compared with healthy brain mRNA (3 samples). Note, however, that no significant difference was observed among the 3 tumor groups. Increased heparanase expression was also found in tumor tissues on Western blotting. Immunohistochemistry staining demonstrated that heparanase was expressed by neovessel endothelial cells, infiltrated neutrophils, and in some cases, by neoplastic cells. Heparanase-expressing cells, including GBM tumor cells and neovessel endothelial cells, exhibited decreased expression of CD44, a cell adhesion molecule on the cell membrane that is important for regulating tumor invasion. In addition, heparanase-expressing tumor cells showed an elevated density of the cell proliferation marker Ki 67, as compared with its density in non–heparanase-expressing tumor cells, suggesting that heparanase expression is correlated with enhanced tumor proliferation. Two animal glioma models were tested for heparanase expression. Both murine astrocytoma cells (Ast11.9-2) and cultured primary human GBM neurospheres expressed heparanase when grown in animal brain tissue. Conclusions Glioma tissues contain increased levels of heparanase. Multiple cell types contribute to the expression of heparanase, including neovessel endothelial cells, tumor cells, and infiltrated neutrophils. Heparanase plays an important role in the control of cell proliferation and invasion. Animal models using Ast11.9-2 and primary neurospheres are suitable for antitumor studies targeting heparanase.

scholarly journals Systemic and Targeted Delivery of Semaphorin 3A Inhibits Tumor Angiogenesis and Progression in Mouse Tumor Models

2011 ◽  
Vol 31 (4) ◽  
pp. 741-749 ◽  
Author(s):  
Andrea Casazza ◽  
Xi Fu ◽  
Irja Johansson ◽  
Lorena Capparuccia ◽  
Fredrik Andersson ◽  
...  
Keyword(s):  
Tumor Angiogenesis ◽  
Targeted Delivery ◽  
Mouse Tumor ◽  
Semaphorin 3A ◽  
Tumor Models ◽  
Mouse Tumor Models

scholarly journals 573 FS120, an OX40/CD137 tetravalent bispecific dual agonist antibody, synergistically increases the antitumor activity of anti-PD-1 in preclinical studies

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A602-A602
Author(s):  
Matthew Lakins ◽  
Wenjia Liao ◽  
Emma McConnell ◽  
Quincy Kaka ◽  
Jennifer Ofoedu ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cell ◽  
Bispecific Antibody ◽  
Cell Activity ◽  
T Cell Proliferation ◽  
Mouse Tumor ◽  
Tumor Models ◽  
Syngeneic Mouse ◽  
Tumor Bearing ◽  
Mouse Tumor Models

BackgroundImmune checkpoint inhibitors have demonstrated durable clinical responses and an increase in overall survival for some patients with cancer. Next generation cancer immunotherapies, such as tumor necrosis factor receptor superfamily (TNFRSF) agonists, have potential to further improve on this success. FS120 is a tetravalent bispecific antibody targeting OX40 and CD137 (4-1BB), currently being evaluated in a Phase I clinical trial (NCT04648202). FS120 activates CD4+ and CD8+ T cells by concurrent binding to both targets via an FcgR-independent mechanism [1]. In preclinical tumor models, FS120 induced T cell proliferation and cytokine production associated with significant tumor regression, better than that observed with a monoclonal antibody combination. Here, we demonstrate the ability of FS120 to improve anti-PD-1 induced T cell activity, increasing tumor growth inhibition and survival, in syngeneic mouse tumor models, compared to monotherapy.MethodsFS120 < i >in vitro</i > activity in combination with anti-PD-1 was assessed by utilizing staphylococcal enterotoxin A (SEA) superantigen assays and mixed leukocyte reaction (MLR) assays. An anti-mouse OX40/CD137 bispecific antibody (FS120 surrogate) was tested in CT26 syngeneic mouse tumor models in combination with an anti-mouse PD-1 antibody to assess efficacy and pharmacodynamic endpoints, including T cell proliferation by < i>ex vivo</i> flow cytometry and serum cytokine levels.ResultsFS120 in combination with anti-PD-1 enhanced primary human T cell activity, when compared to either monotherapy, in both SEA and MLR assays. FS120 surrogate significantly improved survival of CT26 tumor-bearing mice treated with anti-mPD-1 antibody. FS120 surrogate and anti-PD-1 combination significantly enhanced serum interferon-gamma levels and increased proliferating granzyme B+ CD8+ T cells in the blood of tumor-bearing mice, when compared to either monotherapy treatments.ConclusionsFS120 combination with anti-PD-1 enhances T cell activity in multiple human primary immune assays. In combination with anti-PD-1, FS120 surrogate increased the antitumor efficacy with pharmacodynamic changes related specifically to T cell activation, when compared to monotherapies. These data support the development of FS120 in combination with anti-PD-1 in patients with hard-to-treat cancers who may not benefit fully from either treatment as a monotherapy.ReferencesGaspar M, Pravin J, Rodrigues L, Uhlenbroich S, Everett K L, Wollerton F, Morrow M, Tuna M, Brewis N. CD137/OX40 Bispecific Antibody Induces Potent Antitumor Activity that Is Dependent on Target Coengagement. Cancer Immunol Res. 2020; (8) (6) 781–793Ethics ApprovalMurine studies were conducted under a U.K. Home Office License in accordance with the U.K. Animal (Scientific Procedures) Act 1986 and EU Directive EU 2010/63.

MDNA11 is a long-acting IL-2 superkine that potentiates durable immune response in mouse tumor models and non-human primates.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e14546-e14546
Author(s):  
Minh D. To ◽  
Fahar Merchant ◽  
Nina Merchant
Keyword(s):  
T Cells ◽  
Cd8 T Cells ◽  
Cell Activation ◽  
Single Agent ◽  
Mouse Tumor ◽  
Tumor Models ◽  
Toxicology Study ◽  
Long Acting ◽  
Mouse Tumor Models

e14546 Background: The efficacy and safety of recombinant human IL-2 (rhIL-2; Proleukin) to treat certain cancers is limited by a short half-life, marked toxicity and selective high affinity binding to IL2Ra over IL2Rb, resulting in preferential activation of suppressive Tregs. In contrast, MDNA11 has been engineered as a long-acting IL-2 superkine with high affinity IL2Rb receptor selectivity, resulting in preferential anti-cancer effector immune cell activation. Methods: MDNA11 was characterized in both in vitro and in vivo studies including assessment of receptor binding kinetics using BLI/Octet, receptor-mediated signaling in human PMBCs, efficacy in syngeneic mouse tumor models including memory response, as well as safety and PK/PD assessments in non-human primates (NHP). Results: Unlike rhIL-2, MDNA11 does not bind to human IL2Ra but demonstrates a 30-fold higher affinity binding to human IL2Rb. This selectivity resulted in enhanced in vitro STAT5 signaling in human NK and resting CD8 T cells with diminished signaling in Tregs; validation studies in humanized mice are ongoing. In CT26 and MC38 syngeneic tumor models, MDNA11 demonstrates potent and durable efficacy as monotherapy following a Q1W dose schedule for 2 weeks. Synergy with anti-PD1 and anti-CTLA4 immune checkpoint inhibitors (ICIs) was observed and a robust immune memory response developed in all mice with complete tumor clearance. These mice were protected against relapse and tumor re-challenges for up to 8 months without any further treatment, and showed the presence of antigen-specific CD8 T cells. In binding studies with IL-2 receptors of different species, MDNA11 showed highly similar affinity towards human and cynomolgus IL2Rb, confirming the latter as a highly relevant model for toxicology study. MDNA11 was well tolerated in cynomolgus monkeys up to 0.6 mg/kg, while inducing durable (≥10 days) proliferation and expansion of NK and CD8 T cells. Effects on Tregs were minimal and there was no eosinophilia and hypotension (associated with vascular leak syndrome). At high doses of MDNA11, the most common clinical observations were transient loss of appetite and diarrhea. There was modest increase in levels of IFNg and TNFa, but no sign of cytokine release syndrome. Dosing did not trigger development of anti-drug antibodies or histopathologic evidence of pulmonary edema (a major IL-2 induced toxicity). Conclusions: MDNA11 is a long-acting IL-2 superkine that exhibits robust efficacy in mouse tumor models as a single agent and was synergistic in combination with ICIs (anti-CTLA4 and anti-PD1). In NHP, MDNA11 demonstrates selective immune effector cell activation and a favorable safety profile. These data constitute a strong framework for the design of a pivotal GLP toxicology study to further support the planned clinical study of MDNA11 either as a single agent or in combination with ICIs.

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