Meanwhile, Mφ_APOE cluster, preferentially enriched in tumor tissue, was similar to tumor-associated macrophages (TAMs) in hepatocellular carcinoma (HCC) and the lipid-associated macrophages in adipose tissue by expressing APOE, TREM2, C1QA, and GPNMB30,31. This evidence concerns the gene TREM2 and hepatocellular carcinoma.