Plexin-A4 promotes tumor progression and tumor angiogenesis by enhancement of VEGF and bFGF signaling

Blood ◽  
2011 ◽  
Vol 118 (15) ◽  
pp. 4285-4296 ◽  
Author(s):  
Boaz Kigel ◽  
Noa Rabinowicz ◽  
Asya Varshavsky ◽  
Ofra Kessler ◽  
Gera Neufeld

Abstract Plexin-A4 is a receptor for sema6A and sema6B and associates with neuropilins to transduce signals of class-3 semaphorins. We observed that plexin-A1 and plexin-A4 are required simultaneously for transduction of inhibitory sema3A signals and that they form complexes. Unexpectedly, inhibition of plexin-A1 or plexin-A4 expression in endothelial cells using specific shRNAs resulted in prominent plexin type specific rearrangements of the actin cytoskeleton that were accompanied by inhibition of bFGF and VEGF-induced cell proliferation. The two responses were not interdependent since silencing plexin-A4 in U87MG glioblastoma cells inhibited cell proliferation and strongly inhibited the formation of tumors from these cells without affecting cytoskeletal organization. Plexin-A4 formed stable complexes with the FGFR1 and VEGFR-2 tyrosine-kinase receptors and enhanced VEGF-induced VEGFR-2 phosphorylation in endothelial cells as well as bFGF-induced cell proliferation. We also obtained evidence suggesting that some of the pro-proliferative effects of plexin-A4 are due to transduction of autocrine sema6B-induced pro-proliferative signals, since silencing sema6B expression in endothelial cells and in U87MG cells mimicked the effects of plexin-A4 silencing and also inhibited tumor formation from the U87MG cells. Our results suggest that plexin-A4 may represent a target for the development of novel anti-angiogenic and anti-tumorigenic drugs.

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Koudong Zhang ◽  
Hang Hu ◽  
Juan Xu ◽  
Limin Qiu ◽  
Haitao Chen ◽  
...  

Abstract Background Lung cancer (LC) is a malignant tumor originating in the bronchial mucosa or gland of the lung. Circular RNAs (circRNAs) are proved to be key regulators of tumor progression. However, the regulatory effect of circ_0001421 on lung cancer tumorigenesis remains unclear. Methods The expression levels of circ_0001421, microRNA-4677-3p (miR-4677-3p) and cell division cycle associated 3 (CDCA3) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Methyl thiazolyl tetrazolium (MTT), Transwell and Tumor formation assays were performed to explore the role of circ_0001421 in LC. Glucose consumption and lactate production were examined by a Glucose assay kit and a Lactic Acid assay kit. Western blot was utilized to examine the protein levels of Hexokinase 2 (HK2) and CDCA3. The interaction between miR-4677-3p and circ_0001421 or CDCA3 was confirmed by dual-luciferase reporter assay. Results Circ_0001421 was increased in LC tissues and cells, and knockdown of circ_0001421 repressed cell proliferation, migration, invasion and glycolysis in vitro. Meanwhile, circ_0001421 knockdown inhibited LC tumor growth in vivo. Mechanistically, circ_0001421 could bind to miR-4677-3p, and CDCA3 was a target of miR-4677-3p. Rescue assays manifested that silencing miR-4677-3p or CDCA3 overexpression reversed circ_0001421 knockdown-mediated suppression on cell proliferation, migration, invasion and glycolysis in LC cells. Conclusion Circ_0001421 promoted cell proliferation, migration, invasion and glycolysis in LC by regulating the miR-4677-3p/CDCA3 axis, which providing a new mechanism for LC tumor progression.


Author(s):  
Abdellah Akil ◽  
Ana K. Gutiérrez-García ◽  
Rachael Guenter ◽  
J. Bart Rose ◽  
Adam W. Beck ◽  
...  

The Notch signaling pathway plays an essential role in a wide variety of biological processes including cell fate determination of vascular endothelial cells and the regulation of arterial differentiation and angiogenesis. The Notch pathway is also an essential regulator of tumor growth and survival by functioning as either an oncogene or a tumor suppressor in a context-dependent manner. Crosstalk between the Notch and other signaling pathways is also pivotal in tumor progression by promoting cancer cell growth, migration, invasion, metastasis, tumor angiogenesis, and the expansion of cancer stem cells (CSCs). In this review, we provide an overview and update of Notch signaling in endothelial cell fate determination and functioning, angiogenesis, and tumor progression, particularly in the development of CSCs and therapeutic resistance. We further summarize recent studies on how endothelial signaling crosstalk with the Notch pathway contributes to tumor angiogenesis and the development of CSCs, thereby providing insights into vascular biology within the tumor microenvironment and tumor progression.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1897-1897
Author(s):  
Kira Braemswig ◽  
Marina Poettler ◽  
Wazlawa Kalinowska ◽  
Christoph Zielinski ◽  
Gerald W Prager

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.


2001 ◽  
Vol 155 (1) ◽  
pp. 133-144 ◽  
Author(s):  
Isabelle Hoffmann ◽  
Emmanuel Eugène ◽  
Xavier Nassif ◽  
Pierre-Olivier Couraud ◽  
Sandrine Bourdoulous

ErbB2 is a receptor tyrosine kinase belonging to the family of epidermal growth factor (EGF) receptors which is generally involved in cell differentiation, proliferation, and tumor growth, and activated by heterodimerization with the other members of the family. We show here that type IV pilus–mediated adhesion of Neisseria meningitidis onto endothelial cells induces tyrosyl phosphorylation and massive recruitment of ErbB2 underneath the bacterial colonies. However, neither the phosphorylation status nor the cellular localization of the EGF receptors, ErbB3 or ErbB4, were affected in infected cells. ErbB2 phosphorylation induced by N. meningitidis provides docking sites for the kinase src and leads to its subsequent activation. Specific inhibition of either ErbB2 and/or src activity reduces bacterial internalization into endothelial cells without affecting bacteria-induced actin cytoskeleton reorganization or ErbB2 recruitment. Moreover, inhibition of both actin polymerization and the ErbB2/src pathway totally prevents bacterial entry. Altogether, our results provide new insight into ErbB2 function by bringing evidence of a bacteria-induced ErbB2 clustering leading to src kinase phosphorylation and activation. This pathway, in cooperation with the bacteria-induced reorganization of the actin cytoskeleton, is required for the efficient internalization of N. meningitidis into endothelial cells, an essential process enabling this pathogen to cross host cell barriers.


2017 ◽  
Vol 37 (5) ◽  
Author(s):  
Ankit Tiwari ◽  
Niharika Pattnaik ◽  
Archita  Mohanty Jaiswal ◽  
Manjusha Dixit

Facioscapulohumeral muscular dystrophy (FSHD) region gene 1 (FRG1) is a candidate gene for FSHD. FRG1 regulates various muscle-related functions, but studies have proposed its role in development and angiogenesis also, where it is involved with tumor-associated molecules. Therefore, we decided to look into its role in tumor progression, tumor angiogenesis, and its impact on cellular properties. Cell proliferation, migration, invasion and in vitro angiogenesis assays were performed to decipher the effect of FRG1 on endothelial and epithelial cell functions. Q-RT PCR was done for human embyonic kidney (HEK293T) cells with altered FRG1 levels to identify associated molecules. Further, immunohistochemistry was done to identify FRG1 expression levels in various cancers and its association with tumor angiogenesis. Subsequently, inference was drawn from Oncomine and Kaplan–Meier plotter analysis, for FRG1 expression in different cancers. Ectopic expression of FRG1 affected cell migration and invasion in both HEK293T and human umbilical vein endothelial cells (HUVECs). In HUVECs, FRG1 overexpression led to reduced angiogenesis in vitro. No effect was observed in cell proliferation in both the cell types. Q-RT PCR data revealed reduction in granulocyte-colony stimulating factor (G-CSF) expression with FRG1 overexpression and increased expression of matrix metalloproteinase 10 (MMP10) with FRG1 knockdown. Immunohistochemistry analysis showed reduced FRG1 levels in tumors which were supported by in silico analysis data. These findings suggest that reduction in FRG1 expression in gastric, colon and oral cavity tumor might have a role in tumor progression, by regulating cell migration and invasiveness. To elucidate a better understanding of molecular signaling involving FRG1 in angiogenesis regulation, further study is required.


Author(s):  
Lili Quan ◽  
Ryuichi Ohgaki ◽  
Saori Hara ◽  
Suguru Okuda ◽  
Ling Wei ◽  
...  

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.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 2306-2306 ◽  
Author(s):  
Manfai Lee ◽  
Courtney Hoyt ◽  
George M Rodgers

Abstract ADAMTS13, the von Willebrand factor (vWF) cleaving protease, regulates platelet aggregation and microthrombi formation by cleaving high-molecular weight vWF multimers. It is expressed primarily in hepatic stellate cells, but is also found in endothelial cells. Recently, ADAMTS13 was reported to be expressed and regulated in astrocytes, microglial, neuroblastoma, and adult human brain endothelial cells. Previous in vitro studies by our group with human umbilical vein endothelial cells (HUVEC) showed that ADAMTS13 can promote angiogenesis via upregulating the secretion of VEGF and phosphorylation of VEGFR2, suggesting that ADAMTS13 may also be involved in physiological processes unrelated to vWF cleavage (Lee, M., et al. Microvasc Res. 2012, 84, 109-115). Herein, we report an additional possible role of ADAMTS13 secreted by brain tumor cells to modulate tumor cell angiogenesis. Using a human ADAMTS13 immunoassay, we detected ADAMTS13 in U-87 and LN-229 glioblastoma cell lysates, SW-1088 astrocytoma cell lysates, as well as in the supernatants of all cell lines (> 2.0 ng/mL). Co-incubation of U-87, LN-229, and SW-1088 tumor cell conditioned media with recombinant vWF indicated that brain tumor-secreted ADAMTS13 is biologically active in cleaving vWF multimers (measured by ELISA). Secretion of VEGF was upregulated in LN-229 and SW-1088 cell lines by ADAMTS13. 939 pg/mL and 674 pg/mL of VEGF were measured in LN-229 and SW-1088 cell lysates, respectively, after incubation with 100 ng/mL ADAMTS13. Incubation of LN-229 glioblastoma cells with 10 – 500 ng/mL rh-ADAMTS13 or 50 ng/mL VEGF165 did not affect tumor cell proliferation. No change in tumor cell proliferation was observed when LN-229 cells were incubated with a polyclonal antibody against ADAMTS13 in serum free media supplemented with 10 ng/mL ADAMTS13 or media supplemented with 5% FBS, suggesting that ADAMTS13 secreted by brain tumor cells may be involved in extracellular signaling of endothelial cells. Brain tumor cell secreted-ADAMTS13 induced HUVEC migration in a Matrigel invasion assay. Using a modified Boyden chamber fitted with a Matrigel-coated polycarbonate membrane, LN-229 glioblastoma cells increased HUVEC migration by 83%. LN-229 cells supplemented with 10 ng/mL ADAMTS13 further increased HUVEC migration by 190%, suggesting that tumor cell-secreted ADAMTS13 may modulate EC migration (Fig. 1). Combined with our previous findings suggesting that recombinant ADAMTS13 modulates EC angiogenesis, brain tumor-secreted ADAMTS13 may also be a regulator for tumor vasculature angiogenesis. Disclosures: No relevant conflicts of interest to declare.


2020 ◽  
Vol 318 (1) ◽  
pp. F117-F134 ◽  
Author(s):  
Emilia Bigaeva ◽  
Elisabeth G. D. Stribos ◽  
Henricus A. M. Mutsaers ◽  
Bram Piersma ◽  
Anna M. Leliveld ◽  
...  

Poor translation from animal studies to human clinical trials is one of the main hurdles in the development of new drugs. Here, we used precision-cut kidney slices (PCKS) as a translational model to study renal fibrosis and to investigate whether inhibition of tyrosine kinase receptors, with the selective inhibitor nintedanib, can halt fibrosis in murine and human PCKS. We used renal tissue of murine and human origins to obtain PCKS. Control slices and slices treated with nintedanib were studied to assess viability, activation of tyrosine kinase receptors, cell proliferation, collagen type I accumulation, and gene and protein regulation. During culture, PCKS spontaneously develop a fibrotic response that resembles in vivo fibrogenesis. Nintedanib blocked culture-induced phosphorylation of platelet-derived growth factor receptor and vascular endothelial growth factor receptor. Furthermore, nintedanib inhibited cell proliferation and reduced collagen type I accumulation and expression of fibrosis-related genes in healthy murine and human PCKS. Modulation of extracellular matrix homeostasis was achieved already at 0.1 μM, whereas high concentrations (1 and 5 μM) elicited possible nonselective effects. In PCKS from human diseased renal tissue, nintedanib showed limited capacity to reverse established fibrosis. In conclusion, nintedanib attenuated the onset of fibrosis in both murine and human PCKS by inhibiting the phosphorylation of tyrosine kinase receptors; however, the reversal of established fibrosis was not achieved.


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