Journal: bioRxiv
Article Title: Sphingosine-1-phosphate receptor modulators resensitize FLT3-ITD acute myeloid leukemia cells with NRAS mutations to FLT3 inhibitors
doi: 10.1101/2025.11.21.689510
Figure Lengend Snippet: A. Blasts from Patient 1, with FLT3-ITD and an NRAS G13D mutation treated with 1nM quizartinib and/or 2.5µM FTY720, or DMSO control, were harvested for immunoblotting at serial time points and SPHK1, p-AKT/AKT, p-p70 S6K/p70 S6K and p-BAD/BAD protein expression was measured. B . Graphic representation of data in A is shown. SPHK1, p-AKT, p-p70 S6K and p-BAD were downregulated by combination treatment, but not by single-drug treatments. C. Blasts from Patient 1 were incubated for 48 hours with 1nM quizartinib and/or 2.5µM FTY720, or DMSO control, and cytotoxicity was measured using the WST-1 assay. Combination treatment produced markedly greater cytotoxicity, compared to single drugs. D. Blasts from Patient 2, with FLT3-ITD and an NRAS G13V mutation, were treated with 1nM quizartinib and/or 2.5µM FTY720, or DMSO control, for 6 hours, and cells were harvested for immunoblotting. E. Graphic representation of the data in D is shown. SPHK1, p-AKT/AKT, p-p70 S6K/p70 S6K and p-BAD/BAD were downregulated by combination treatment, but not by single-drug treatments.
Article Snippet: FLT3 inhibitors included lestaurtinib (CEP-701; HY-50867, MedChem Express, Monmouth Junction, NJ) and gilteritinib (ASP 2215; S7754) (Type I), and quizartinib (AC220, S1526) (Type II) (Selleck Chemicals, Houston, TX).
Techniques: Mutagenesis, Control, Western Blot, Expressing, Incubation, WST-1 Assay, Produced