In addition to being expressed on the tumor surface and participating in immune escape, PD-L1 is also expressed on the surface of antigen presenting cells (DC cells, macrophages, etc.)and vascular endothelial cells under the stimulation of IFN-γ, which indicates that the infiltration of tumor cells, DC cells or macrophages increases in the lymph node metastasis group. Here, CD274 is linked to metastatic malignant neoplasm in the lymph nodes.