Therapeutic Efficacy of Malachite Green-Based Photodynamic Therapy in Acute Myeloid Leukemia

Aim: Acute myeloid leukemia (AML) is a disease characterized by relapse and treatment resistance in most patients. Therefore, there is a need for targeted therapies in AML. Photodynamic therapy (PDT) is a promising alternative for the treatment of malignant tumors. Also, PDT has the potential to be used individually or complementally in the treatment of leukemia. In this study, it was aimed to investigate possible the effect of malachite green (MG)-based PDT on acute myeloid leukemia cells. Materials and Methods: Cells were incubated with 0.19, 0.39, 0.78,1.56, 3.125, and 6.25 µM MG for one hour and irradiated with 46.4 J/cm2 of light. The trypan blue test was used to assess the viability of cells, and the change in mitochondrial activity was determined by MTT. Morphological features were determined by Giemsa staining and scanning electron microscopy. Cell cycle and Annexin V/PI assays (measuring fluorescence emitted by staining reagents) were measured by flow cytometry. Results: With the combination of MG and light, HL60 cell viability was found to be significantly reduced compared to the control group. Giemsa staining and SEM results showed that 3.125 μM MG-based PDT induced various morphological changes in cells typical for apoptosis. Late apoptosis was observed in cells treated with 3.125 μM MG combined PDT according to Annexin/PI staining, further showing that it caused an arrest in the subG1 phase of the cell cycle. Conclusion: MG-based PDT has the potential to inactivate HL60 cells. Thus, MG-based PDT may ensure a promising approach for treating acute myeloid leukemia cells.