This discovery awarded Tasuku Honjo and James P. Allison the 2018 Nobel Prize of Physiology or Medicine for the discovery of the programmed death molecule-1 (PD-1) and cytotoxic T-lymphocyte antigen-4 (CTLA-4) on T-cells, respectively, which culminated in the development of the groundbreaking cancer therapy known as immune checkpoint blockade [64]. Here, CTLA4 is linked to cancer.