Moreover, not only (increased) PD1- and CTLA4-expressing T-cells, but also PD1- and CTLA4-expressing (circulating) disseminated cancer cells were detected in patients with solid tumors (e.g., melanoma; lung, breast, and pancreatic cancer); (Hodgkin/Non-Hodgkin) lymphoma or leukemia [10,12,33,37,38,39,40]. Here, CTLA4 is linked to leukemia.