CCR4 and hepatocellular carcinoma: Moreover, CCR4+ Tregs have been found to be an important type of Tregs in HBV+ HCC, correlated with sorafenib resistance and increased IL-10 and IL-35 levels, and treatment with a CCR4+ antagonist has been shown to successfully reverse sorafenib resistance and sensitize liver cancers to PD-L1 checkpoint blockade (70).