BioProject

CIC-DUX4 sarcoma (CDS) or CIC-rearranged sarcoma is a subcategory of small round cell sarcoma resembling the morphological phenotypes of Ewing sarcoma (ES). More...

CIC-DUX4 sarcoma (CDS) or CIC-rearranged sarcoma is a subcategory of small round cell sarcoma resembling the morphological phenotypes of Ewing sarcoma (ES). Recent clinicopathologic and molecular genetic analyses indicate that CDS is an independent disease entity from ES. Although a few ancillary markers have been used in the differential diagnosis of CDS, additional CDS-specific biomarkers are needed in challenging diagnosis for a more definitive classification. Here we have generated an ex vivo mouse model for CDS by transducing embryonic mesenchymal cells (eMCs) with human CIC-DUX4 cDNA. The recipient mice transplanted with eMCs expressing CIC-DUX4 rapidly developed an aggressive, undifferentiated sarcoma composed of small round to short spindle cells. Gene expression profiles of CDS and eMCs revealed upregulation of CIC-DUX4 downstream genes such as PEA3 family genes, Ccnd2, Crh and Zic1. Immunohistochemical analyses for both mouse and human tumors showed that CCND2 and MUC5AC are reliable biomarkers to distinguish CDS from ES. Gene silencing of CIC-DUX4 as well as Ccnd2, Ret, and Bcl2, that are upregulated in CDS, effectively inhibited tumor growth in vitro. Palbociclib, a CDK4/6 inhibitor, also showed growth inhibition of mouse CDS cells in vitro, while trabectedin induced tumor suppressive effects both in vitro and in vivo. In summary, the CDS mouse model provides important biological information of CDS and is a useful platform to explore novel biomarkers and therapeutic agents for CDS. We used microarrays to detail the global program of gene expression in mouse CDS. Overall design: Murine embryonic mesenchymal cells were transduced with the CIC-DUX4 and transplanted into nude mice. Tumor developed as a subcutaneous mass and histological examination was performed to confirm the CDS phenotypes. Individual tumor tissues and embryonic mesenchymal cells (eMCs) transduced with the CIC-DUX4 retrovirus were subjected to microarray analyses. eMCs introduced with an empty vector was used as a control. In addition, mouse ES tumors were also subjected to microarray analyses and expression profiles were compared between CDS and ES. Less...