For instance, Wang et al. [58] conducted pooled in vivo CRISPR knockout (KO) screens in syngeneic triple-negative breast cancer (TNBC) mouse models and found that deleting the E3 ubiquitin ligase Cop1 in cancer cells reduced the secretion of macrophage-associated chemokines, reducing tumor macrophage infiltration, enhancing antitumor immunity, and strengthening the response to immune checkpoint blockade therapy. Here, COP1 is linked to cancer.