Abstract 606: Celastrol treatment induces apoptosis and modulates metabolic pathways in FLT3 - Positive acute myeloid leukemia cells

Abstract Acute Myeloid Leukemia (AML) is a hematologic malignancy with poor prognosis. Historically, its treatment is associated with severe toxicity and mortality. Moreover, the success of chemotherapy is often hampered by drug resistance and relapse, affecting treatment response and long-term survival of patients. To find alternative drugs and targeted immunotherapies for AML remains an unmet need. Celastrol is a natural compound isolated from the medicinal plant Tripterygium wilfordii Hook F. It is a pentacyclic triterpenoid, that has shown therapeutical potential due to its anti-inflammatory and anti-cancer properties, yet the mechanism is poorly understood. In the present study, we demonstrate the cytotoxic effects of celastrol in FLT3 ITD mutated AML. Molecular docking studies confirmed celastrol’s effective binding to the FLT3 protein, suggesting a potential targeted therapy. Cell viability and apoptosis were determined after celastrol treatment in MV-4-11 cells at varying concentrations, and cell viability was hampered in a dose-dependent manner with an IC50 value of 0.3μM. Next, Annexin V and PI staining were used to examine whether this inhibitory effect of celastrol on cell viability was related to the induction of apoptosis. Celastrol-induced cell apoptosis was demonstrated ranging from 75 to 78 % along with increased apoptotic markers like caspase 3, caspase 8, and caspase 9 expression, confirming its ability to trigger the apoptotic cascade through intrinsic and extrinsic pathways. Seahorse assay revealed that celastrol treatment significantly suppressed the maximal oxygen consumption rate (OCR) with minimal effect on basal respiration. Interestingly, combination treatment with celastrol and Giltertinib strongly suppressed maximal OCR. In addition, celastrol treatment affected the extracellular acidification rate (ECAR) in MV-4-11 cells showing a compensatory decrease in glycolysis. Furthermore, untargeted metabolomics showed 18 significantly changed metabolites with better variance between the vehicle and celastrol treatment as evidenced by principal component analysis (PCA). Pathway analysis revealed alterations in glutathione, lipid, and energy metabolism after celastrol treatment. This study demonstrated that celastrol treatment targets both glutathione and glycolysis metabolism which are crucial for cell survival and will potentially be a powerful strategy to induce a more selective, metabolically driven toxicity on FLT3-positive AML cells. The ongoing transcriptomics analysis and the in vivo experiments will delineate celastrol's potential role in treating AML. Citation Format: Biba Vikas, Vasantharaja Raguraman, Shanid Mohiyuddin, Sofia Vega, Zhentian Lei, Gerhard Hildebrandt, Senthilnathan Palaniyandi. Celastrol treatment induces apoptosis and modulates metabolic pathways in FLT3 - Positive acute myeloid leukemia cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 606.