Relevance of p53 pathway activation in MTBITC-triggered growth arrest.

<p>(a) gene expression analysis of wt-p53 (HepG2) mRNA using real - time PCR arrays. The scatter blot compares expression of 84 p53 pathway genes between solvent and 25 µM MTBITC treated (3 h) cells. The solid diagonal line represents no change in expression. Any data point above the upper line represents genes that are upregulated >4-fold. Any data point below the lower line represents genes that are downregulated >4-fold. Values are mean of three independent experiments. Immunoblotting of p53 pathway related proteins (b) or p21 (c) after exposure to MTBITC or solvent to HCC cells. β-actin was used as loading control. (d and e) silencing of p53 in wt-p53 (HepG2) cells using RNAi. HepG2 cells were reverse transfected with p53-RNAi or nonsense RNAi for 24 h and then exposed to MTBITC or solvent for another 24 h. Impact of p53-RNAi on MTBITC-induced mitochondrial membrane potential collapse (MMP) (d) or G2/M arrest (e). Bars are mean ± SD, (n = 3). (f and g) RT-MLPA mRNA expression analysis of pro- and anti-apoptotic Bcl-2 family members in MTBITC-treated HCC cells, bars are mean+SD. (n = 3). All results in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0070846#pone-0070846-g005" target="_blank">figure 5</a> were calculated relative to the solvent control (SC, 0.1% DMSO).