Consistent with the findings in transwell invasion assay, small LoVo cells initiated more lung metastatic lesions than the corresponding large cells in NOD/SCID mice (Figure 4C and 4D), and furthermore, immunostaining confirmed that the metastatic cells were positive for CRC epithelial markers such as CK20 and EpCAM (Figure 4C). Here, EPCAM is linked to colorectal carcinoma.