Patients with lung cancer brain metastasis (n = 34) had increased PD-L1+ peripheral monocyte, the MDSC abundance (CD33+, CD11b+, HLA-DRlow) and Treg percentage (CD3+, CD4+, CD25+, FoxP3+) compared to early-stage pre-metastatic patients (n = 15). The gene discussed is CD274; the disease is lung carcinoma.