Based on our previous characterization of the p33 form in cancer cells from hematopoietic origin, i.e., acute myeloid leukemia (36), we tested the distribution of APE1 in EXE of OCI-AML3 (expressing the mutated NPM1c+ protein) and OCI-AML2 control cells (45). The gene discussed is RUNX3; the disease is acute myeloid leukemia.