AUTHOR=Scannell Christopher A., Pedersen Elisabeth A., Mosher Jack T., Krook Melanie A., Nicholls Lauren A., Wilky Breelyn A., Loeb David M., Lawlor Elizabeth R. TITLE=LGR5 is Expressed by Ewing Sarcoma and Potentiates Wnt/β-Catenin Signaling JOURNAL=Frontiers in Oncology VOLUME=3 YEAR=2013 URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2013.00081 DOI=10.3389/fonc.2013.00081 ISSN=2234-943X ABSTRACT=
Ewing sarcoma (ES) is an aggressive bone and soft tissue tumor of putative stem cell origin that predominantly occurs in children and young adults. Although most patients with localized ES can be cured with intensive therapy, the clinical course is variable and up to one third of patients relapse following initial remission. Unfortunately, little is yet known about the biologic features that distinguish low-risk from high-risk disease or the mechanisms of ES disease progression. Recent reports have suggested that putative cancer stem cells exist in ES and may contribute to an aggressive phenotype. The cell surface receptor leucine-rich repeat-containing G-protein coupled receptor 5 (LGR5) is a somatic stem cell marker that functions as an oncogene in several human cancers, most notably colorectal carcinoma. LGR5 is a receptor for the R-spondin (RSPO) family of ligands and RSPO-mediated activation of LGR5 potentiates Wnt/β-catenin signaling, contributing to stem cell proliferation and self-renewal. Given its presumed stem cell origin, we investigated whether LGR5 contributes to ES pathogenesis. We found that