CTLA4 and hepatocellular carcinoma: Interestingly, the expression of DCK was associated with the gene markers like CCR8, STAT5b, and TGFB1 of Tregs, and PD–1, CTLA–4, LAG3, TIM–3, and GZMB of exhausted T cells after adjusting tumor purity (Fig. 4a, b), revealing that increased expression of DCK was associated with immunosuppression in HCC.