CD4 and hepatocellular carcinoma: TH17 cells are CD4+ IL-17+ T cells differentiated from naïve CD4+ TH0 cells through the action of cytokines such as IL-6, TGF-β1, IL-21, and IL-1β, which in turn activate downstream transcription factors such as STAT3, RAR-related orphan receptor γt (RORγt) and RORα, which are all essential for the expression of TH17-specific cytokines and can potentially be considered treatment options in the context of HCC [252].