Furthermore, we observed that while there was no change in luciferase-expressing cells homing in the bone marrow or tumor of PBS- and Slit2-pretreated allografted mice (Supplementary Figure 1), the Slit2-pretreated allograft-recipient PyMT had a higher population of F4/80+CD38+ M1 macrophages in tumors (75.7 ± 14.8% cells) compared to PBS-pretreated allograft-recipient PyMT tumors (22.1 ± 12.1% cells, n = 5, *p < 0.05) (Figure 1F). This evidence concerns the gene CD38 and neoplasm.