CD4 and neoplasm: We found that RAB6B expression was significantly positively correlated with infiltration level of B cells (r = 0.267, p = 5.02e-07), CD8+ T cells (r = 0.281, p = 1.30e-07), CD4+ T cells (r = 0.444, p = 4.72e-18), Macrophages (r = 0.474, p = 1.81e-20), Neutrophils (r = 0.39, p = 6.02e-14), and Dendritic cells (r = 0.409, p = 3.54e-15) but negatively correlated with tumor purity (r = −0.199, p = 1.96e-04) in HCC (Figure 4D).