WT1 and neoplasm: The Wilms' tumor 1 (WT1) gene encodes a zinc-finger transcription factor that has an important role in the differentiation, proliferation and migration of malignant cells.1, 2, 3 The gene product, WT1 protein, is expressed in various hematological and solid malignancies4 but is negligibly expressed in normal tissues, thus making WT1 an ideal target for cancer immunotherapy strategies.5 CD8+ T cells are sentinels of the immune system characterized by their ability to detect and kill tumor cells within the tissue and peripheral blood.