To test this hypothesis, pre-labeled HCT116 and DAPK1 ko clone 21/9 tumor cells were transplanted onto the CAM and whole bodies of freshly sacrificed chicken embryos were screened for optical signals using an intravital imaging system (IVIS Spectrum, Perkin Elmer; Fig. 4f, Supplementary Fig. 5b). The gene discussed is DAPK1; the disease is neoplasm.