Purpose: Acute myeloid leukemia (AML) is the most frequent leukemia identified in 25% of adults and in 15-20% of children. In the current study, the cytotoxicity and apoptosis-inducing properties of davanone - a terpenoid, were examined on human AML cell line NCI-H526 and normal AML-193 cell line.
Methods: The cytotoxic effects were examined through MTT assay and apoptosis was studied through DAPI and Annexin V/PI staining. Further, the effect on MMP and ROS levels were investigated through flow cytometry. Cell migration and invasion were determined by wound healing and cell invasion assays respectively. Western blotting analysis was performed to study the expressions of apoptosis and PI3K/AKT/MAPK signalling pathway associated proteins.
Results: The results revealed that Davanone induced cytotoxicity in NCI-H526 cells in a dose-dependent manner without causing too much toxicity to the normal AML-193 cells. Further investigations were done in order to validate whether the cytotoxicity was apoptosis-mediated, and the results revealed that cytotoxicity of the test molecule was apoptosis-dependent. On further investigations through western blotting analysis, cytotoxicity was shown to be due to caspase-dependent apoptosis with increased expressions of caspase-3 and Bax and decreased expressions of Bcl-2. Next, it was seen that Davanone treatment led to decrease in mitochondrial membrane potential (MMP) and an increase in reactive oxygen species formation (ROS). The tested molecule also significantly suppressed cell invasion and migration of leukemia cells. Finally, the effect on PI3K/AKT/MAPK signalling pathway was examined and the expression of related proteins was altered significantly.
Conclusions: The present study outcomes propose that Davanone terpenoid could be considered as a promising anticancer agent for AML.