Figure 6

The Akt mRNA levels and caspase activities of the SiHa cells. (A) The relative mRNA abundance of Akt1, Akt2 and Akt3 in the HeLa and SiHa cells were assessed by quantitative RT-PCR and plotted as fold variations of Akt1 mRNA level of the HeLa cells. 18S was used as an internal control. Error bars represent standard deviations of three independent experiments. (B) The relative level of Akt3 mRNA following 16 hours of exposure to valproic acid (VPA, 2 mM) or sodium butyrate (NaB, 5 mM) was plotted as arbitrary units (A.U.) of the mRNA abundance. (C) The level of caspase-9 mRNA in the SiHa cells was examined by quantitative real-time RT-PCR analysis following valproic acid or butyrate treatment. Results are expressed as fold induction of the transcripts relative to untreated controls. Error bars represent standard deviations of three independent experiments. (D) The experimental set up was as in panel A except that the caspase-9 mRNA level in untreated SiHa cells was compared to untreated HeLa cells. (E) Following 16 hours of valproic acid or butyrate treatment, the SiHa cells were assayed for their caspase-8 and caspase-9 activities. Results show fold induction of the activities relative to untreated controls after background subtraction of zero time signals. Error bars represent standard deviations of five independent experiments.