Consistent with the polarization trends in our whole-tumor bulk RNA-sequencing and single-cell RNA-sequencing of BMDMs (Fig. 1E, 1I–J), we find that BMDMs co-cultured in tumoroids of MPS1i-treated B16F10 showed increased expression of M1-like, anti-cancer macrophage markers MHCII and CD86 while having decreased expression of M2-like, pro-cancer markers CD163 and CD206 (Fig. 2B–C). Here, MRC1 is linked to cancer.