Dibromo-Edaravone Induces Anti-Erythroleukemia Effects via the JAK2-STAT3 Signaling Pathway

Acute erythroid leukemia (AEL) is a rare and aggressive hematological malignancy managed with chemotherapy, targeted therapies, and stem cell transplantation. However, these treatments often suffer from limitations such as refractoriness, high toxicity, recurrence, and drug resistance, underscoring the urgent need for novel therapeutic approaches. Dibromo-edaravone (D-EDA) is a synthetic derivative of edaravone (EDA) with unreported anti-leukemic properties. In this study, D-EDA demonstrated potent cytotoxicity against HEL cells with an IC₅₀ value of 8.17 ± 0.43 μM using an MTT assay. Morphological analysis via inverted microscopy revealed reductions in cell number and signs of cellular crumpling and fragmentation. Flow cytometry analysis, Hoechst 33258 staining, Giemsa staining, a JC-1 assay, and a reactive oxygen species (ROS) assay showed that D-EDA induced apoptosis in HEL cells. Furthermore, D-EDA induced S-phase cell cycle arrest. Western blot analysis showed significant upregulation of key apoptosis-related proteins, including cleaved caspase-9, cleaved caspase-3, and cleaved poly ADP-ribose polymerase (PARP), alongside a reduction in Bcl-2 expression. Additionally, oncogenic markers such as c-Myc, CyclinA2, and CDK2 were downregulated, while the cell cycle inhibitor p21 was upregulated. Mechanistic studies involving molecular docking, a cellular thermal shift assay (CETSA), the caspase inhibitor Z-VAD-FMK, JAK2 inhibitor Ruxolitinib, and STAT3 inhibitor Stattic revealed that D-EDA activates the caspase cascade and inhibits the JAK2-STAT3 signaling pathway in HEL cells. In vivo, D-EDA improved spleen structure, increased the hemolysis ratio, and extended survival in a mouse model of acute erythroleukemia. In conclusion, D-EDA induces apoptosis via the caspase cascade and JAK2-STAT3 signaling pathway, demonstrating significant anti-leukemia effects in vitro and in vivo. Thus, D-EDA may be developed as a potential therapeutic agent for acute erythroleukemia.