Moreover, Hiroto Kikuchi et al. find that when hepatocellular carcinoma is first treated with PD-1 inhibitors, subsequent administration of the anti-angiogenic agent sorafenib (a multi-kinase inhibitor with anti-VEGFR1-3 activity) can enhance the response of hepatocellular carcinoma to sorafenib. Here, PDCD1 is linked to hepatocellular carcinoma.