Anti-CTLA-4 antibodies with optimal Fc effector function reinforce the MECA-79+CD62P+ bifunctional phenotype of TA-HECs and increase their proportion in tumor microvasculature by selectively pruning MECA-79− non-HEV TA-ECs, while Fc-null anti-CTLA-4 antibodies do not have any activity on tumor endothelial cells. The gene discussed is CTLA4; the disease is neoplasm.