Investigating the apoptotic effect of cyclophosphamide in combination with BV6 in acute lymphoblastic leukemia

Abstract

Resistance to chemotherapy is one of the most common events observed in many leukemias, including acute lymphocytic leukemia (ALL). Despite the use of different chemotherapy methods alongside a variety of immunotherapies, there is still no definitive cure for ALL. As a result, efforts to increase the effectiveness of treatment methods continue. One of the newer methods of immunotherapy is the use of tools to increase susceptibility to apoptosis and break the resistance of cancer cells to chemotherapy. One of these ways is the use of Smac mimetics such as BV6, which increases the sensitivity of cells to apoptosis. Therefore, in this study, it was decided to increase their sensitivity to cyclophosphamide by using nanocarriers and by transferring BV6to cancer cells. Materials and Methods: This study was performed on two cell lines Jurkat and NALM6 as well as peripheral blood mononuclear cells of 10 ALL patients. Carboxymethyl dextran-coated trimethyl chitosan nanoparticles were used for simultaneous delivery of BV6and cyclophosphamide to cancer cells. H1NMR and FTIR tests were used to study the chemical structure of nanoparticles. Also, the entry of nanoparticles into cancer cells was examined by flow cytometry and confocal microscopy. MTT technique was used to evaluate the toxicity of nanoparticles. The effect of combination therapy on cell apoptosis was evaluated by flow cytometry. Evaluation of target gene expression in cancer cells was also performed by real-time PCR. Results: The results showed that the produced nanoparticles had a size of about 105, zeta potential of 18 and PDI <0.2. These physicochemical properties led to proper loading of BV6and cyclophosphamide and significantly delivered them to cancer cells. Co-administration of BV6and cyclophosphamide to cancer cells reduced the survival of cancer cells and broke their resistance to apoptosis, which was associated with decreased Bcl-2 expression and increased Bax expression.