{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T13:32:23Z","timestamp":1770903143132,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2016,9,23]],"date-time":"2016-09-23T00:00:00Z","timestamp":1474588800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Neuroblastoma (NB) is the most common extracranial solid tumor of childhood and is a rapidly growing, highly-vascularized cancer. NBs frequently express angiogenic factors and high tumor angiogenesis has been associated with poor outcomes. Placental growth factor (PlGF) is an angiogenic protein belonging to the vascular endothelial growth factor (VEGF) family and is up-regulated mainly in pathologic conditions. Recently, PlGF was identified as a member of a gene expression signature characterizing highly malignant NB stem cells drawing attention as a potential therapeutic target in NB. In the present study, we sought to investigate the expression of PlGF in NB patients and the effect of PlGF inhibition on high-risk MYCN-non-amplified SK-N-AS NB xenografts. Human SK-N-AS cells, which are poorly differentiated and express PlGF and VEGF-A, were implanted subcutaneously in athymic nude mice. Treatment was done by intratumoral injection of replication-incompetent adenoviruses (Ad) expressing PlGF- or VEGF-specific short hairpin (sh)RNA, or soluble (s)VEGF receptor 2 (VEGFR2). The effect on tumor growth and angiogenesis was analyzed. High PlGF expression levels were observed in human advanced-stage NBs. Down-regulating PlGF significantly reduced NB growth in established NB xenografts by reducing cancer cell proliferation but did not suppress angiogenesis. In contrast, blocking VEGF by administration of Ad(sh)VEGF and Ad(s)VEGFR2 reduced tumor growth associated with decreased tumor vasculature. These findings suggest that PlGF and VEGF-A modulate MYCN-non-amplified NB tumors by different mechanisms and support a role for PlGF in NB biology.<\/jats:p>","DOI":"10.3390\/ijms17101613","type":"journal-article","created":{"date-parts":[[2016,9,23]],"date-time":"2016-09-23T07:32:37Z","timestamp":1474615957000},"page":"1613","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["PlGF and VEGF-A Regulate Growth of High-Risk MYCN-Single Copy Neuroblastoma Xenografts via Different Mechanisms"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0202-2364","authenticated-orcid":false,"given":"Karin","family":"Zins","sequence":"first","affiliation":[{"name":"Division of Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, A-1090 Vienna, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniel","family":"Kovatchki","sequence":"additional","affiliation":[{"name":"Division of Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, A-1090 Vienna, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Trevor","family":"Lucas","sequence":"additional","affiliation":[{"name":"Division of Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, A-1090 Vienna, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6337-0058","authenticated-orcid":false,"given":"Dietmar","family":"Abraham","sequence":"additional","affiliation":[{"name":"Division of Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, A-1090 Vienna, Austria"},{"name":"Comprehensive Cancer Center (CCC), Medical University of Vienna, A-1090 Vienna, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,9,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"472","DOI":"10.1016\/S1470-2045(03)01166-5","article-title":"Neuroblastoma: Biology and molecular and chromosomal pathology","volume":"4","author":"Schwab","year":"2003","journal-title":"Lancet Oncol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1466","DOI":"10.1200\/JCO.1993.11.8.1466","article-title":"Revisions of the international criteria for neuroblastoma diagnosis, staging, and response to treatment","volume":"11","author":"Brodeur","year":"1993","journal-title":"J. Clin. Oncol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2202","DOI":"10.1056\/NEJMra0804577","article-title":"Recent advances in neuroblastoma","volume":"362","author":"Maris","year":"2010","journal-title":"N. Engl. J. Med."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1645","DOI":"10.1016\/j.ejca.2008.05.015","article-title":"Angiogenesis as a target in neuroblastoma","volume":"44","author":"Rossler","year":"2008","journal-title":"Eur. J. Cancer"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"405","DOI":"10.1200\/JCO.1996.14.2.405","article-title":"Tumor angiogenesis correlates with metastatic disease, n-myc amplification, and poor outcome in human neuroblastoma","volume":"14","author":"Meitar","year":"1996","journal-title":"J. Clin. Oncol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"212","DOI":"10.1016\/j.critrevonc.2012.11.004","article-title":"Anti-angiogenesis in neuroblastoma","volume":"86","author":"Ribatti","year":"2013","journal-title":"Crit. Rev. Oncol. Hematol."},{"key":"ref_7","first-page":"1900","article-title":"High-level expression of angiogenic factors is associated with advanced tumor stage in human neuroblastomas","volume":"6","author":"Eggert","year":"2000","journal-title":"Clin. Cancer Res."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"3999","DOI":"10.1038\/onc.2008.15","article-title":"N-myc is a novel regulator of PI3K-mediated VEGF expression in neuroblastoma","volume":"27","author":"Kang","year":"2008","journal-title":"Oncogene"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1002\/ijc.10742","article-title":"In vivo angiogenic activity of neuroblastoma correlates with mycn oncogene overexpression","volume":"102","author":"Ribatti","year":"2002","journal-title":"Int. J. Cancer"},{"key":"ref_10","first-page":"401","article-title":"Vascular endothelial growth factor blockade rapidly elicits alternative proangiogenic pathways in neuroblastoma","volume":"34","author":"Zaghloul","year":"2009","journal-title":"Int. J. Oncol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"419","DOI":"10.1016\/j.scr.2015.08.008","article-title":"A distinct gene expression signature characterizes human neuroblastoma cancer stem cells","volume":"15","author":"Ross","year":"2015","journal-title":"Stem Cell Res."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"575","DOI":"10.1038\/87904","article-title":"Synergism between vascular endothelial growth factor and placental growth factor contributes to angiogenesis and plasma extravasation in pathological conditions","volume":"7","author":"Carmeliet","year":"2001","journal-title":"Nat. Med."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"a011056","DOI":"10.1101\/cshperspect.a011056","article-title":"PLGF: A multitasking cytokine with disease-restricted activity","volume":"2","author":"Dewerchin","year":"2012","journal-title":"Cold Spring Harb. Perspect. Med."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1515","DOI":"10.1182\/blood-2002-11-3423","article-title":"Mechanism of monocyte activation and expression of proinflammatory cytochemokines by placenta growth factor","volume":"102","author":"Selvaraj","year":"2003","journal-title":"Blood"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"585","DOI":"10.1007\/s00281-013-0367-7","article-title":"Tumor-associated macrophages: Functional diversity, clinical significance, and open questions","volume":"35","author":"Biswas","year":"2013","journal-title":"Semin. Immunopathol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"305","DOI":"10.1530\/ERC-12-0223","article-title":"Placental growth factor supports neuroendocrine tumor growth and predicts disease prognosis in patients","volume":"20","author":"Hilfenhaus","year":"2013","journal-title":"Endocr. Relat. Cancer"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"669","DOI":"10.1038\/nm0603-669","article-title":"The biology of VEGF and its receptors","volume":"9","author":"Ferrara","year":"2003","journal-title":"Nat. Med."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"2039","DOI":"10.1056\/NEJMra0706596","article-title":"Tumor angiogenesis","volume":"358","author":"Kerbel","year":"2008","journal-title":"N. Engl. J. Med."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"750","DOI":"10.1016\/S0959-8049(01)00337-9","article-title":"Angiogenesis and anti-angiogenesis in neuroblastoma","volume":"38","author":"Ribatti","year":"2002","journal-title":"Eur. J. Cancer"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1016\/j.ctrv.2004.09.006","article-title":"Antiangiogenic strategies in neuroblastoma","volume":"31","author":"Ribatti","year":"2005","journal-title":"Cancer Treat. Rev."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"582","DOI":"10.1053\/jpsu.2002.31614","article-title":"Upregulation of vascular endothelial growth factor receptors is associated with advanced neuroblastoma","volume":"37","author":"Fakhari","year":"2002","journal-title":"J. Pediatr. Surg."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"739","DOI":"10.1007\/s004320100293","article-title":"Expression of angiogenic factors and tumor progression in human neuroblastoma","volume":"127","author":"Komuro","year":"2001","journal-title":"J. Cancer Res. Clin. Oncol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1431","DOI":"10.1158\/1078-0432.CCR-09-1936","article-title":"Neuroblastoma progression correlates with downregulation of the lymphangiogenesis inhibitor sVEGFR-2","volume":"16","author":"Becker","year":"2010","journal-title":"Clin. Cancer Res."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1200\/JCO.2000.18.1.27","article-title":"Angiogenesis in neuroblastoma: Relationship to survival and other prognostic factors in a cohort of neuroblastoma patients","volume":"18","author":"Canete","year":"2000","journal-title":"J. Clin. Oncol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1016\/S0304-3835(03)00082-X","article-title":"The regulation of angiogenesis in neuroblastoma","volume":"197","author":"Chlenski","year":"2003","journal-title":"Cancer Lett."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1016\/j.canlet.2005.01.049","article-title":"Prospects for therapeutic inhibition of neuroblastoma angiogenesis","volume":"228","author":"Shusterman","year":"2005","journal-title":"Cancer Lett."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"399","DOI":"10.1200\/JCO.2007.11.9230","article-title":"Phase I trial and pharmacokinetic study of bevacizumab in pediatric patients with refractory solid tumors: A children\u2019s oncology group study","volume":"26","author":"Adamson","year":"2008","journal-title":"J. Clin. Oncol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"807","DOI":"10.1093\/annonc\/mdm510","article-title":"Compassionate use of bevacizumab (Avastin\u00ae) in children and young adults with refractory or recurrent solid tumors","volume":"19","author":"Benesch","year":"2008","journal-title":"Ann. Oncol."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Ribatti, D. (2016). Tumor refractoriness to anti-VEGF therapy. Oncotarget.","DOI":"10.18632\/oncotarget.8694"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1038\/nrc2152","article-title":"Possible molecular mechanisms involved in the toxicity of angiogenesis inhibition","volume":"7","author":"Verheul","year":"2007","journal-title":"Nat. Rev. Cancer"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"10","DOI":"10.3858\/emm.2012.44.1.023","article-title":"Role of placenta growth factor in cancer and inflammation","volume":"44","author":"Kim","year":"2012","journal-title":"Exp. Mol. Med."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1016\/j.mvr.2012.05.009","article-title":"Post-transcriptional regulation of placenta growth factor mRNA by hydrogen peroxide","volume":"84","author":"Shaw","year":"2012","journal-title":"Microvasc. Res."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1016\/S0165-0378(03)00082-2","article-title":"Evidence of a novel isoform of placenta growth factor (PLGF-4) expressed in human trophoblast and endothelial cells","volume":"60","author":"Yang","year":"2003","journal-title":"J. Reprod. Immunol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1227","DOI":"10.1016\/j.febslet.2005.01.017","article-title":"Upregulation of placental growth factor by vascular endothelial growth factor via a post-transcriptional mechanism","volume":"579","author":"Yao","year":"2005","journal-title":"FEBS Lett."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1016\/j.cell.2010.02.039","article-title":"Further pharmacological and genetic evidence for the efficacy of plgf inhibition in cancer and eye disease","volume":"141","author":"Stalmans","year":"2010","journal-title":"Cell"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"166","DOI":"10.1016\/j.cell.2010.01.033","article-title":"PLGF blockade does not inhibit angiogenesis during primary tumor growth","volume":"141","author":"Bais","year":"2010","journal-title":"Cell"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"740","DOI":"10.1016\/j.ccr.2011.05.007","article-title":"Loss or inhibition of stromal-derived PLGF prolongs survival of mice with imatinib-resistant Bcr-Abl1+ leukemia","volume":"19","author":"Schmidt","year":"2011","journal-title":"Cancer Cell"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"976","DOI":"10.1158\/1078-0432.CCR-10-2687","article-title":"Placental growth factor upregulation is a host response to antiangiogenic therapy","volume":"17","author":"Bagley","year":"2011","journal-title":"Clin. Cancer Res."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"417","DOI":"10.1038\/nrd3455","article-title":"Principles and mechanisms of vessel normalization for cancer and other angiogenic diseases","volume":"10","author":"Carmeliet","year":"2011","journal-title":"Nat. Rev. Drug Discov."},{"key":"ref_40","first-page":"1","article-title":"Clinicopathological considerations on angiogenic potential in neuroblastoma schwannian stroma\u2014Poor tumours","volume":"45","author":"Drozynska","year":"2007","journal-title":"Folia Neuropathol."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1002\/(SICI)1097-0215(19990331)81:1<113::AID-IJC19>3.0.CO;2-L","article-title":"Vascular endothelial growth factor expression in human neuroblastoma: Up-regulation by hypoxia","volume":"81","author":"Rossler","year":"1999","journal-title":"Int. J. Cancer"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1115","DOI":"10.1016\/j.ajpath.2012.07.013","article-title":"Tumor cell vasculogenic mimicry: From controversy to therapeutic promise","volume":"181","author":"Seftor","year":"2012","journal-title":"Am. J. Pathol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"376","DOI":"10.1200\/JCO.2006.09.0696","article-title":"Tumor origin of endothelial cells in human neuroblastoma","volume":"25","author":"Pezzolo","year":"2007","journal-title":"J. Clin. Oncol."},{"key":"ref_44","first-page":"679","article-title":"Homozygous deletion of cdkn2a (p16INK4a\/p14ARF) but not within 1p36 or at other tumor suppressor loci in neuroblastoma","volume":"61","author":"Thompson","year":"2001","journal-title":"Cancer Res."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"2342","DOI":"10.1002\/stem.145","article-title":"Adenoviral-mediated endothelial precursor cell delivery of soluble CD115 suppresses human prostate cancer xenograft growth in mice","volume":"27","author":"Lucas","year":"2009","journal-title":"Stem Cells"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"17958","DOI":"10.3390\/ijms140917958","article-title":"Inhibition of stromal PLGF suppresses the growth of prostate cancer xenografts","volume":"14","author":"Zins","year":"2013","journal-title":"Int. J. Mol. Sci."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"4349","DOI":"10.1158\/0008-5472.CAN-05-3523","article-title":"Colony-stimulating factor-1 antibody reverses chemoresistance in human MCF-7 breast cancer xenografts","volume":"66","author":"Paulus","year":"2006","journal-title":"Cancer Res."},{"key":"ref_48","doi-asserted-by":"crossref","unstructured":"Zins, K., Schafer, R., Paulus, P., Dobler, S., Fakhari, N., Sioud, M., Aharinejad, S., and Abraham, D. (2016). Frizzled2 signaling regulates growth of high-risk neuroblastomas by interfering with \u03b2-catenin-dependent and \u03b2-catenin-independent signaling pathways. Oncotarget.","DOI":"10.18632\/oncotarget.10070"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"295","DOI":"10.1186\/1479-5876-11-295","article-title":"Targeting Cdc42 with the small molecule drug AZA197 suppresses primary colon cancer growth and prolongs survival in a preclinical mouse xenograft model by downregulation of PAK1 activity","volume":"11","author":"Zins","year":"2013","journal-title":"J. Transl. Med."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/17\/10\/1613\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T19:31:40Z","timestamp":1760211100000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/17\/10\/1613"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,9,23]]},"references-count":49,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2016,10]]}},"alternative-id":["ijms17101613"],"URL":"https:\/\/doi.org\/10.3390\/ijms17101613","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2016,9,23]]}}}