NCAM1 and neoplasm: Both the number of human CD45+CD56+ cells and the ratio of human CD45+CD56+ cells to the mouse CD45+ cells were significantly higher in tumor-bearing mice than that in non-tumor-bearing mice (Figure 3d,e), both of which reached their highest values at day 7 in non-tumor-bearing mice, but peaked at day 10 in tumor-bearing mice (Figure 3c,e).