Tetrahydroindazolone-substituted Benzamide Compound W-H4 Induces Apoptosis and Autophagy of Acute Myeloid Leukemia Cells

Background/Aim: Acute myeloid leukemia (AML) is an aggressive hematologic malignancy. Hsp90 inhibitors, like SNX-2112, are promising anti-cancer agents. However, SNX-2112’s clinical use is limited by poor solubility and side effects. This study aimed to improve tetrahydroindazolone-substituted benzamide compounds and to investigate its mechanism of action against AML cells.

Materials and Methods: The anti-proliferative effects of nine tetrahydroindazolone-substituted benzamide derivatives were evaluated across eight cancer cell lines using the CCK-8 assay. W-H4 was identified as the most potent compound and further investigated for its effects on acute myeloid leukemia (AML) cells. Analyses of apoptosis, autophagy, and cell cycle arrest were conducted using flow cytometry and Western blotting, while mitochondrial membrane potential (MMP) was assessed via JC-1 staining.

Results: W-H4, a tetrahydroindazolone-substituted benzamide, effectively inhibited the proliferation of acute myeloid leukemia (AML) cells in vitro. The compound destabilized Hsp90 client proteins and induced autophagy, as indicated by LC3-II accumulation. Additionally, W-H4 caused G₀/G₁ cell cycle arrest and triggered both caspase-dependent and intrinsic apoptosis, accompanied by modulation of Bcl-2 family proteins and a decrease in mitochondrial membrane potential. These results highlight W-H4’s potential as a therapeutic agent for AML treatment.

Conclusion: W-H4 emerges as a potential Hsp90 inhibitor, providing novel therapeutic opportunities for the targeted treatment of acute myeloid leukemia.