APOE and neoplasm: On the other hand, single-cell transcriptomics of cholangiocarcinoma and anti-CSF1R–treated tumors, identified a unique granulocytic myeloid-derived suppressor cell (G-MDSCs) subset, ApoE G-MDSCs, with abundant expression of ApoE in the vehicle-treated tumors and marked ApoE downregulation with tumor-associated tumor blockade (Loeuillard et al., 2020).