Expressão recombinante das L-asparaginases bacterianas ANSB e ANSZ e avaliação de seus potenciais citotóxicos

Abstract

Cancer is a devastating pathological condition characterized by the uncontrolled proliferation of cells in various tissues. In addition, L-asparaginase (L-ASNase) is an enzyme that catalyzes the hydrolysis of L-asparagine, an amino acid essential for the growth and survival of certain types of cancer cells, it has been used clinically for over 50 years as a a standard component of chemotherapy regimens for acute lymphoblastic leukemia (ALL) in children and adults. Furthermore, not long ago the worldwide production and distribution of L-ASNase was hampered by several challenges and these factors led to shortages of L-ASNase in many countries, including Brazil. Also, conventional cancer treatments often involve a combination of chemotherapy, radiation therapy, and targeted therapies, but these treatments can have negative side effects. That said, there is an urgent need to develop new and innovative approaches to generate more efficient cancer treatments and to overcome the shortage of this drug. The objective of this work was the heterologous expression of L-asparaginases B and Z in Escherichia coli, in addition to the evaluation of cytotoxicity in tumor cell lines. The 12.5% polyacrylamide gel electrophoresis (SDS-PAGE) method was used to ensure the result of expression and purification, while the cytotoxicity assay was performed with the MTT method, calculating the IC50. It was possible to observe that L-ASNase B needed a lower concentration to inhibit half of the cells, showing that it has greater cytotoxic activity. Finally, the importance of the biochemical characterization of L-asparaginases for the advancement of cancer treatment can be highlighted, as these enzymes can contribute to the development of more effective therapies against this devastating disease.