To test whether the overexpressed CD13 had enzymatic activity, aminopeptidase-activated release of 7-AMC from alanine-AMC was measured in 1F6, 1F6-pcDNA3 and clones highly overexpressing 18kD or ALL bFGF isoform proteins (Figure 3). The gene discussed is ANPEP; the disease is acute lymphoblastic leukemia.