CD72 is a pan‐tumor antigen associated to pediatric acute leukemia

Abstract

AbstractIn the development of novel immunotherapeutic approaches, the step of target identification is a challenging process, because it aims at identifying robust tumor‐associated antigens (TAAs) specific for the pathological population and causing no off‐target effects. Here we propose CD72 as a novel and robust TAA for pediatric acute leukemias. We provided an outline of CD72 expression assessed by flow cytometry on a variety of cancer cell lines and primary samples, including normal bone marrow (BM) samples and hematopoietic stem and progenitor cells. We analyzed CD 72 expression on a cohort of 495 pathological pediatric BM aspirates, including: 215 B‐cell precursor acute lymphoblastic leukemias (BCP‐ALL), 156 acute myeloid leukemias (AMLs), 88 T‐lineage ALLs or lymphoblastic lymphomas with BM infiltration, 13 B‐lineage lymphoblastic lymphomas with BM infiltration, 9 myelodysplastic syndromes with increased blasts (5%–9% blasts on BM: MDS‐IB1) and 14 non‐hematopoietic solid tumors infiltrating BM. Results showed that CD72 is highly expressed in almost all BCP‐ALL and the majority of AML at diagnosis, including BCP‐ALL cases characterized by CD19 loss. These findings support a potential role for advanced diagnostics and novel immunotherapy approaches, providing a pan‐ALL and AML target.