The potential use of recombinant immunotoxin and BCL-2 inhibitors for leukemic stem cell elimination

Leukemia is a type of hematological malignancy caused by the dysfunctional proliferation of leukocyte cells. According to the Global Burden of Disease 2019 report, there were over 643,579 new cases of leukemia cancer worldwide in 2020, killing 334,592 people. Chemotherapy, an important part of the treatment of leukemia, not only harm cancer cells but also harm healthy cells, which can lead to negative side effects. This article examines the possibility for cutting-edge therapy using targeted recombinant immunotoxins and BCL-2 inhibitors as targeted therapy against leukemic stem cells. Recombinant immunotoxin is a protein-based therapeutic agent composed of toxins combined with specific antibodies or other molecules such as growth factors, cytokines, or toxins. Diphtheria Toxin (DT) is the most commonly used toxin because it is easily expressed, making the toxin easier to take. The toxin kills cancer cells by inhibiting enzymatic cell protein synthesis. While immunotoxins enhance therapeutic outcomes by targeting leukemia stem cells, their efficacy can be compromised in certain patients due to apoptosis resistance mediated by proteins like BCL-2. The presence of anti-apoptotic protein BCL-2 enables cell survival even after exposure to immunotoxins. Consequently, combining recombinant immunotoxins and BCL-2 inhibitors holds promise for eradicating LSC and preventing relapse.