MRC1 and neoplasm: To explore the effect of siSLITRK4‐NPs on the immune microenvironment, CT26 tumor‐bearing mouse models were generated and administered with siSLITRK4‐NPs (Figure 6a), then we examined the T cell and macrophage populations and found that siSLITRK4‐NPs decreased the abundance of CD206+CD11b+ macrophages and increased the abundance of CD8+Ki67+ macrophages (Figure 6b).