Page 121 - Haematologica Vol. 110 - January 2025

ARTICLE - LIPA modulates venetoclax/TKI response in bpCML M. Minhajuddin et al.
cells to attempt survival. Since LIPA is known to regulate free fatty acid levels, we performed metabolomic analy- sis of LSC isolated after treatment with ven/dasa for 4 h. We found that several fatty acids were upregulated in the ven/dasa-treated cells. Recent work has demonstrated that increased fatty acid metabolism may be a mecha-
nism for AML resistance to conventional chemotherapies such as cytarabine27,37 and our laboratory has previously reported that increased expression of genes involved in fatty acid metabolism correlates with a poor response of AML to venetoclax/azacitidine.28,29 We hypothesized that activation of fatty acid processing through enhanced LIPA
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Figure 7. Endogenous LIPA and CPT1A are critical for resistance to venetoclax/dasatinib in mouse leukemia cells. (A) mRNA lev- el of LIPA in LIPA knockout (sgRNA-LIPA) and scramble control (Scr-sgRNA) GY leukemia cells using the CRISPR/CAS9 method. (B) Western blot of LIPA in LIPA-knockout and scramble control leukemia cells. (C) Viability of LIPA knockout and scramble control GY leukemia cells treated with the venetoclax/dasatinib (Ven/Dasa) combination (100 nM) relative to the viability of untreated cells. (D) mRNA level of LIPA in LIPA overexpressing (OE) and vector control GY leukemia cells. (E) Western blot of LIPA in LIPA OE and vector control GY leukemia cells. (F) Viability of LIPA OE cells treated with Ven/Dasa (100 nM) compared to vector control GY leukemia cells, normalized to untreated cells. (G) mRNA level of CPT1A after 48 h of siRNA knockdown compared to scramble control in GY leukemia cells. (H) Viability of siRNA-mediated CPT1A knockdown and scramble control GY leukemia cells after treatment with Ven/Dasa (100 nM) relative to the viability of untreated cells. **P≤0.01.
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