CSPG4 and acute lymphoblastic leukemia: CSPG4, previously named human homologue of NG2, is absent on the surface of healthy cells of the hematopoietic system, but is aberrantly expressed on the leukemic blasts of a proportion of pediatric (11–35%) and adult AML (13–36%) patients, as well as in ALL [15,16,17,18,19].