SLC40A1 and hepatocellular carcinoma: Six macrophage clusters were identified in comprehensive analysis of immune cell composition in HCC patients from five immune‐related sites with full‐length and 3′scRNA‐Seq technology, and mutually exclusive signals of S100 calcium‐binding protein A8 (S100A8) and SLC40A1 were detected on different cells in CD68 macrophages, indicating the existence of two distinct macrophage states in HCC, namely the coexistence of M1 and M2.13