LMP1 and CD40 are involved in various malignant diseases of the hematopoietic system, such as Hodgkin's and non-Hodgkin's lymphoma, post-transplant lymphoproliferative disease, or chronic lymphocytic leukemia, as well as in non-hematopoietic cancers such as nasopharyngeal carcinoma or renal carcinoma [60]–[62]. Here, CD40 is linked to post-transplant lymphoproliferative disease.