ASNS and acute lymphoblastic leukemia: It was found in the 1970s that the use of bacterial asparaginase (ASNase) could cure children with pediatric acute lymphoblastic leukemia (ALL) when used as a single agent or as a combination therapy, due to low expression of asparagine synthetase (ASNS) (Figure 1), the enzyme that converts aspartate to asparagine in leukemic blasts (18).