The DCK expression was associated with dismal outcomes and positively correlated with the infiltration levels of B cells (cor = 0.351, p = 1.97 × 10− 11), CD8+ T cells (cor = 0.310, p = 4.57 × 10− 9), CD4+ T cells (cor = 0.419, p = 4.61 × 10− 16), macrophages (cor = 0.484, p = 1.84 × 10− 21), neutrophils (cor = 0.556, p = 2.50 × 10− 29), and dendritic cells (cor = 0.485, p = 2.00 × 10− 21) in HCC (Fig. 3). This evidence concerns the gene CD4 and hepatocellular carcinoma.