The representative images of FOXP3+Tregs (a) CD163+M2 macrophages (b); the representative positive expression of PD-L1 in tumor tissues (c); the representative negative expression of PD-L1 in tumor tissues (d); CD3+T lympmcytes (e); CD8+T lympmcytes (f). Here, FOXP3 is linked to neoplasm.