For example, inhibition of apolipoprotein C1 (APOC1) restores ferroptosis sensitivity, leading to the conversion of tumor-associated macrophages from an M2 to an M1 phenotype and enhancing anti-PDCD1 immunotherapy against hepatocellular carcinoma and lung cancers [280, 281]. This evidence concerns the gene APOC1 and hepatocellular carcinoma.