anlotinib alters tumor immune microenvironment by downregulating PD-L1 expression on vascular endothelial cells

Aberrant vascular network is a hallmark of cancer. However, the role of vascular endothelial cells (VECs)-expressing PD-L1 in tumor immune microenvironment and antiangiogenic therapy remains unclear. In this study, we used the specimens of cancer patients for immunohistochemical staining to observe the number of PD-L1 + CD34 + VECs and infiltrated immune cells inside tumor specimens. Immunofluorescence staining and flow cytometry were performed...