Fig. 5

HHT enhanced Ara-C-induced apoptosis by p38 MAPK/H2AX/Mcl-1 axis. A, HL-60 cells were pretreated with the p38 inhibitor SB203580 (10 μM) for 4 h and then treated with 30 nM HHT and/or 120 nM Ara-C for another 24 h, after which apoptosis was examined by AO-EB staining. B, C, Apoptotic cells were detected by Annexin V/PI staining. *, P < 0.05; **, P < 0.01; ***, P < 0.001. D, Protein expression of HL-60 cells treated with SB203580, HHT or Ara-C. E, F, p38 was silenced with p38 siRNA in THP-1 cells that were subsequently treated with HHT and Ara-C