Establishment of an NOD/SCID Mouse Model for Ewing Tumors: A Potential Preclinical Model to Test Novel Purging Strategies

A quantity of 1 – 5 × 106 cells from the Ewing tumor cell lines VH-64, WE-68 and CADO-ESi were transplanted via tail vein injection into immune-deficient NOD/SCID mice. VH-64, WE-68 and CADO-ES1 cells after intravenous injection caused macroscopic disease in transplanted mice. Highly engrafted mice developed lung, bone, kidney and ovary metastases and a diffuse infiltration of the bone marrow. By RT-PCR the EWS/FLII and EWS/ERG transcripts characteristic for the transplanted cell lines could be detected in the tumors and the bone marrow of the mice. These results indicate that human Ewing tumor cells are able to home and proliferate in immune-deficient NOD/SCID mice in a fashion similar to that seen in patients. As normal hematopoietic cells and Ewing tumor cells can be co-transplanted, this model may be useful as a preclinical purging model.