Activation of the mitochondrial signalling pathway. A. SH-EP, LAN-1, and IMR32 cells were untreated (no) or treated with NaB, SAHA or TSA for 48 h as indicated in Fig. 2A and 2B. B. SH-EP cells were treated with NaB, SAHA or TSA (as in Fig. 2A) for 16, 24, or 48 h. The loss of ΔΨm was measured by flow cytometry using the fluorescent dye JC-1. The percentage of cells with low ΔΨm is indicated. Mean of two independent experiments are indicated in B.