CD8A and hepatocellular carcinoma: For HCC, we observed that the level of XDH expression was positively correlated with the infiltration levels of CD8+ T cells (r = 0.157, p=3.46e−03) and macrophages (r = 0.221, p = 3.40e−05) but negatively correlated with the infiltration levels of B cells (r = − 0.178, p = 8.68e−04) and myeloid DCs (r = − 0.179, p=8.66e−04; Fig. 4A).