Probes stimulate HEXIM1 expression in LNCaP cells. The cells were treated with DMSO, HMBA (5 mM), HMBA probe (200 μM), 4a1 (250 μM), 4a1 probe (200 μM) for 24 h. The results represent three independent experiments and the representative one or the mean is presented (±SD). (A) A representative western blot result of HEXIM1 expression. (B) The densitometry measurement of the band intensities of three western blots. *P <0.01 vs. DMSO by unpaired t test, #p <0.05 vs DMSO by unpaired t test.