In 2013, the academic journal Science designated cancer immune therapy as “breakthrough of the year”, and in 2018, James P Allison and Tasuko Honjo were awarded the Nobel Prize in Physiology or Medicine for their respective discovery of the canonical immunoregulatory systems cytotoxic T-lymphocyte antigen (CTLA)-4 and programmed death receptor (PD)-1/programmed death receptor ligand (PD-L)1, and cancer immune therapy is now used with great success in the treatment of several solid cancers. Here, CTLA4 is linked to cancer.