Microbial L-asparaginase as a promising enzyme for treatment of various cancers.

Metabolic differences between normal and cancerous cells have been used as a point of view for developing anticancer drugs. Some degrading enzymes of certain amino acids have been regarded to kill cancerous cells. L-Asparaginase (ASNase) has shown an excellent therapeutic response to asparagine-auxotrophic cancers such as acute lymphoblastic leukemia (ALL). Some bacteria, yeasts, molds, plants, and animals produce ASNase. Bacterial ASNases from Escherichia coli and Erwinia chrysanthemi are the FDA-approved drugs for ALL treatment. Here, we review new natural prokaryotic and eukaryotic sources of ASNases, recent advances to introduce improvement strategies for the production of recombinant ASNases as well as their chemical modifications, immobilization, nanoencapsulation, and in silico studies to increase efficiency and decrease side effects. Recent studies for application of ASNases to treatment of asparagine-auxotrophic cancers, especially solid cancers, have been reviewed. Furthermore, challenges and future perspectives are discussed for this promising therapeutic enzyme. KEY POINTS: • Review recent advances to introduce new sources of microbial L-asparaginases. • Review improvement strategies for the development of stable and non-toxic L-asparaginases. • Review microbial L-asparaginase application in various cancers' treatment.