Our findings implied that the expression level of HOXB4 had an apparently positive correlation with infiltrating levels of CD8+ T cells (r=0.193, P=9.12e-05), CD4+ T cells (r=0.142, P=4.22e-03), macrophages (r = 0.136, P=6.30e-03), neutrophils (r=0.203, P=4.23e-05), dendritic cells (r=0.195, P=8.28e-05) and tumor purity in COAD, but no association was observed with B cells (r=0.014, P=4.10e-01) (Figures 6A, B). This evidence concerns the gene CD8A and neoplasm.