In an ex vivo FLT3-ITD AML specimen (#13), 100 nM dasatinib for 2 h reduced pY88-p27 to 38% of vehicle, while the combination with 100 nM AC220 reduced it to 23%. Responses varied across other specimens, including little or no effect in some samples. These findings concern a phosphorylation endpoint and do not establish clinical benefit. [2]
Native BCR-ABL and T315I differ in dasatinib signaling response
Cell-based study · Ba/F3 cells expressing native BCR-ABL or BCR-ABL T315I [1]
Dasatinib reduced phosphorylated CrkL in native BCR-ABL cells but did not appreciably reduce it in T315I cells at the tested concentration. This is a signaling comparison, not a dasatinib IC50 determination.
Literature-Reported Treatment Conditions
- Treatment concentration
- 50 nM dasatinib
- Exposure duration
- 4 h
- Method
- Cells cultured in complete medium; CrkL immunoblot mobility-shift analysis.
- Co-treatment
- Dasatinib alone; imatinib, nilotinib and AP24534 were separate comparators.
- Reported limits
- Stock solvent and exact dasatinib material form are not specified in the inspected main methods. Replicate count is not given in Figure 3 caption.
Methods and source locations
Compound reported in the paper: Dasatinib (BMS-354825); Compound label in the paper: dasatinib
Compound-level literature evidence; no salt conversion or Adooq lot validation.
Figure 3A–B, caption; Results AP24534 Inhibits BCR-ABL-Mediated Signaling; Experimental Procedures CrkL Phosphorylation in Ba/F3 Cell Lines and Inhibitors
CrkL phosphorylation in native BCR-ABL cells: CrkL immunoblot and densitometry; no exact bar value inferred. — Figure 3A–B, caption; Results AP24534 Inhibits BCR-ABL-Mediated Signaling; Experimental Procedures CrkL Phosphorylation in Ba/F3 Cell Lines and Inhibitors
CrkL phosphorylation in BCR-ABL T315I cells: Matched CrkL immunoblot comparison. — Figure 3A–B, caption; Results AP24534 Inhibits BCR-ABL-Mediated Signaling; Experimental Procedures CrkL Phosphorylation in Ba/F3 Cell Lines and Inhibitors
Ex vivo AML phosphorylation responses to dasatinib were heterogeneous
Cell-based study · Primary human AML blast cells, with quantitative emphasis on FLT3-ITD sample #13 [2]
In sample #13, dasatinib alone lowered pY88-p27 to 38% of vehicle; dasatinib plus AC220 lowered it to 23%. The main text and supplementary captions also report samples with little or no response. These ex vivo findings do not establish clinical efficacy or a unique kinase responsible.
Literature-Reported Treatment Conditions
- Treatment concentration
- 100 nM dasatinib; 100 nM AC220 in the combination/comparator conditions
- Exposure duration
- 2 h inhibitor exposure
- Method
- Primary cells in RPMI with 20% serum; pY88-p27 immunoprecipitation followed by p27 immunoblot.
- Vehicle
- DMSO (supplementary sample-lane labels); vehicle control in main figure.
- Co-treatment
- Dasatinib alone and dasatinib plus AC220 are distinct conditions; AC220 alone is a comparator.
- Reported limits
- Independent replicate count and uncertainty for sample #13 percentages not stated in the selected result. Serum described as FCS in Methods and FBS in Figure 6 caption; both indicate 20% supplementation. No population response estimate is inferred.
Methods and source locations
Compound reported in the paper: Dasatinib (BMS-354825); Compound label in the paper: dasatinib
Compound-level and reported-supplier applicability only.
Figure 7D and caption (conditions referred to Figure 6); Results p27 is phosphorylated on Y88 in primary AML cells; Discussion; Supplementary Methods Reagents/Antibodies and S10/S11 captions
pY88-p27, FLT3-ITD AML sample #13: Reported in Results; immunoprecipitation/immunoblot, Figure 7D. No curve-derived precision. — Results p27 is phosphorylated on Y88 in primary AML cells, sample #13 paragraph; Figure 7D
pY88-p27, sample #13, dasatinib plus AC220: Same ex vivo comparison; combination outcome kept separate from dasatinib alone. — Results sample #13 paragraph; Figure 7D
pY88-p27 response across additional selected AML samples: Main Results/Discussion and original S10/S11 captions; supplemental blot images were not rendered, so no visual or numeric quantification is asserted. — Results primary AML final paragraphs; Discussion; Supplement S10/S11 captions (PDF pages 12–13)
