Because D2.0R cells are of mouse origin, we were unable to use CD298 to detect tumor cells and although we attempted PNA, EpCAM, and mouse cytokeratin staining of these cells in vitro (data not shown), we were unable to find a cell marker suitable for flow cytometry that was uniquely expressed on tumor cells and not on mouse bone marrow cells. This evidence concerns the gene ATP1B3 and neoplasm.