Cell cycle–associated gene expression is modulated by HDAC11 inhibitors that arrest MPN cells in G₁. (A) HEL92.1.7 JAK2^V617F-positive MPN cell line was treated with 8 μM FT234 or inactive control FT650 for 6, 12, or 24 hours. CDKN1A messenger RNA (mRNA) expression was examined by quantitative reverse transcription polymerase chain reaction. Statistical analysis was performed by using two-tailed unpaired Student t test. (B) Cell cycle–related proteins were measured by western blot in HEL92.1.7 cells treated with FT234 at indicated doses for 12 hours. Asterisks indicate experiments run on a different blot; a β-actin loading control for the blot is provided. (C-D) HEL92.1.7 cells were treated with DMSO (vehicle) or FT234 and (E) FT895 at the indicated doses for 12 hours. Cell cycle was then assessed by flow cytometry, and data were analyzed using ModFit LT software. Multiple Student t tests (compared with DMSO in each group) were performed to assess significant differences. ****P < .0001; ***P < .01.