PDCD1 and neoplasm: Antiangiogenic therapy can inhibit angiogenic signalling and result in normalisation of the tumour vasculature to diminish the immunosuppression exerted by immunosuppressive cells (e.g., Tregs, tumour-associated macrophages, and myeloid-derived suppressor cells), as well as inhibit the expression of PD-1 and regulate apoptotic pathways in cytotoxic CD8+ T cells, thereby improving the efficacy of immunotherapy47,48.