A novel naphthylchalcone ([E]-4-(3-[naphthalen-2-yl]-3-oxoprop-1-en-1-yl) induces intrinsic and extrinsic apoptosis in human acute leukemia cell lines

Background: Chalcones have been described in the literature as promising antineoplastic compounds.

Objectives: Therefore, the objective of this study was to analyze the cytotoxic effect of 23 synthetic chalcones on human acute leukemia (AL) cell lines (Jurkat and K562).

Methods: Cytotoxicity assessment was performed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Cell death was evaluated using fluorescence microscopy, the DNA fragmentation technique, and the assessment of proteins involved in apoptosis by flow cytometry.

Results: The most cytotoxic chalcone (R32) showed no cytotoxicity towards peripheral blood mononuclear cells (PBMC). It exhibited no hemolytic activity, did not alter platelet aggregation after adenosine diphosphate (ADP) and epinephrine stimulation, and did not affect blood coagulation as measured by prothrombin time (PT) and activated partial thromboplastin time (APTT). R32 demonstrated cytotoxic activity by inducing both intrinsic and extrinsic apoptosis, leading to caspase-3 activation and DNA fragmentation. In Jurkat and K562 cells, intrinsic apoptosis was associated with changes in mitochondrial membrane potential (MMP). There was a decreased expression of Bcl-2, increased expression of Bax, decreased expression of survivin, and increased expression of apoptosis-inducing factor (AIF). Extrinsic apoptosis involvement was also observed in both cell lines, characterized by increased expression of the Fas receptor. Additionally, Jurkat cells exhibited decreased expression of the KI-67 cell proliferation marker.

Conclusion: These findings suggest R32 as a potential compound for the development of novel drugs for the treatment of AL.