Within these clusters, well-known hepatocellular carcinoma biomarkers such as alpha fetoprotein (AFP) and Dickkopf-related protein 1 (DKK1)[26] were identified, as well as proteins that have been suggested to be related to metastasis in other studies, for example, integrin alpha-3 (ITGA3) and tissue inhibitor of metalloproteinase-1 (TIMP-1)[21]. This evidence concerns the gene DKK1 and hepatocellular carcinoma.