Figure 3.
HDAC11-specific inhibitors suppress JAK-STAT signaling, induce apoptosis, and inhibit colony formation in MPN cells and patient samples. (A) HEL92.1.7 MPN cells were treated with FT234 for 16 hours at concentrations of 1, 3, 4, or 8 µM, and the proportion of viable, early apoptotic, late apoptotic, and necrotic cells was measured by flow cytometry. (B) JAK-STAT pathway activation, ac-tubulin, and ac-H3 were detected by western blot in HEL92.1.7 MPN cells treated with the indicated concentrations of FT234 or FT895 for 24 hours. (C-F) EPO-independent colony formation assays were conducted on JAK2V617F-positive MPN patient cells or healthy donor cells treated with FT234, FT895, or FT383 at indicated doses. (C) Treatment with FT234 vs treatment with DMSO vehicle control. (D) Ruxolitinib 50 nM (an established IC50 in similar assays) in a subset of 5 MPN patients treated with FT234 in panel C. (E) FT895 treatment at indicated concentrations vs DMSO control. (F) FT383 treatment at indicated concentrations vs DMSO control. (G) Control (Ctrl) BM cultured in cytokines and BM from MPN patients shown in panel F treated with FT383 (EPO-independent colonies) were compared. Each patient and control sample was analyzed in duplicate. (H) Expression of Gfp-JAK2V617F and Gfp-MPLW515L in transduced Ba/F3 mice was determine by flow cytometry. (I) Total apoptosis of parental Ba/F3 (P) grown in IL-3 and MPLW515L transformed Ba/F3 (M) grown in the absence of IL-3 after 24-hour treatment with DMSO or indicated concentration of panobinostat. Data represent a summary of 2 independent experiments. (J) Apoptosis of parental Ba/F3 (P) grown in IL-3, JAK2V617F transformed Ba/F3 (J), and MPLW515L transformed Ba/F3 (M) grown in the absence of IL-3 after 24-hour treatment relative to DMSO or indicated concentrations of FT895 and FT383. Data represent a summary of 3 independent experiments. Statistical analysis was performed by using ANOVA followed by Dunnett’s multiple comparison test with DMSO group or parental group as control. ****P < .0001; ***P < .001; **P < .01; *P < .05. gMFI, geometric mean fluorescence intensity.

HDAC11-specific inhibitors suppress JAK-STAT signaling, induce apoptosis, and inhibit colony formation in MPN cells and patient samples. (A) HEL92.1.7 MPN cells were treated with FT234 for 16 hours at concentrations of 1, 3, 4, or 8 µM, and the proportion of viable, early apoptotic, late apoptotic, and necrotic cells was measured by flow cytometry. (B) JAK-STAT pathway activation, ac-tubulin, and ac-H3 were detected by western blot in HEL92.1.7 MPN cells treated with the indicated concentrations of FT234 or FT895 for 24 hours. (C-F) EPO-independent colony formation assays were conducted on JAK2V617F-positive MPN patient cells or healthy donor cells treated with FT234, FT895, or FT383 at indicated doses. (C) Treatment with FT234 vs treatment with DMSO vehicle control. (D) Ruxolitinib 50 nM (an established IC50 in similar assays) in a subset of 5 MPN patients treated with FT234 in panel C. (E) FT895 treatment at indicated concentrations vs DMSO control. (F) FT383 treatment at indicated concentrations vs DMSO control. (G) Control (Ctrl) BM cultured in cytokines and BM from MPN patients shown in panel F treated with FT383 (EPO-independent colonies) were compared. Each patient and control sample was analyzed in duplicate. (H) Expression of Gfp-JAK2V617F and Gfp-MPLW515L in transduced Ba/F3 mice was determine by flow cytometry. (I) Total apoptosis of parental Ba/F3 (P) grown in IL-3 and MPLW515L transformed Ba/F3 (M) grown in the absence of IL-3 after 24-hour treatment with DMSO or indicated concentration of panobinostat. Data represent a summary of 2 independent experiments. (J) Apoptosis of parental Ba/F3 (P) grown in IL-3, JAK2V617F transformed Ba/F3 (J), and MPLW515L transformed Ba/F3 (M) grown in the absence of IL-3 after 24-hour treatment relative to DMSO or indicated concentrations of FT895 and FT383. Data represent a summary of 3 independent experiments. Statistical analysis was performed by using ANOVA followed by Dunnett’s multiple comparison test with DMSO group or parental group as control. ****P < .0001; ***P < .001; **P < .01; *P < .05. gMFI, geometric mean fluorescence intensity.

Close Modal
This Feature Is Available To Subscribers Only

or Create an Account

Close Modal
Close Modal