Work

CD49b inhibits osteogenic differentiation and plays an important role in osteosarcoma progression

Year: 2017

Type: article

Abstract: // Tingting Ren 1, 2 , Sajida Piperdi 2 , Pratistha Koirala 2 , Amy Park 2 , Wendong Zhang 2 , Daria Ivenitsky 2 , Yidan Zhang 1, 2 , Esperanza Villanueva-Siles 3 , Douglas S. Hawkins 4 , Michael Roth 2 and Richard Gorlick 5 1 Department of Orthopedics, Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, China 2 Department of Pediatrics, Division of Hematology/Oncology, The Children’s Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, NY, USA 3 Department of Pathology, Montefiore Medical Center, Bronx, NY, USA 4 Department of Pediatrics, Division of Hematology/Oncology, Seattle Children’s Hospital, Fred Hutchinson Cancer Research Center, University of Washington, Seattle, WA, USA 5 Department of Pediatrics, Children’s Cancer Hospital, The University of Texas MD Anderson Cancer Center, Houston, TX, USA Correspondence to: Richard Gorlick, email: [email protected] Keywords: CD49b, osteosarcoma, osteogenic differentiation, mesenchymal stem cells, osteoblasts Received: June 03, 2017 Accepted: August 23, 2017 Published: September 23, 2017 ABSTRACT Osteosarcoma is a cancer whose cell of origin lies in the differentiation pathway between the mesenchymal stem cell (MSC) and the osteoblast (OB). In this study, we sought to determine if surface markers associated with osteoblastic differentiation are involved in osteosarcoma progression. cDNA expression arrays were performed on MSCs and osteoblasts to identify differentially expressed genes. The specificity of candidate genes for osteoblast differentiation was assessed through time course experiments in differentiation media with confirmation utilizing CD49b transfected MSCs. In addition, CD49b was transfected into osteosarcoma cell lines to determine its impact on cell proliferation, motility, and invasion. Finally, the expression of CD49b was assessed in osteosarcoma patient samples and correlated with survival outcomes. cDNA expression arrays identified a list of genes differentially expressed between MSCs and osteoblasts with a subset of those genes encoding cell surface proteins. Three genes were selected for further analysis, based on qPCR validation, but only CD49b was selective for osteoblastic differentiation. Forced expression of CD49b in MSCs led to delayed osteoblastic differentiation. Down-regulation of CD49b expression in osteosarcoma cell lines resulted in inhibition of their migration and invasion capacity. CD49b expression in osteosarcoma patients was associated with presence of metastases and inferior 5 year overall survival (31.4% vs. 57.4%, p=0.03). Surface proteins involved in osteosarcoma cell differentiation, such as CD49b, have the potential to serve as prognostic biomarkers, and may lead to the identification of new therapeutic targets.

Source: Oncotarget

DOI: 10.18632/oncotarget.21254