MicroRNAs that respond to histone deacetylase inhibitor SAHA and p53 in HCT116 human colon carcinoma cells

MicroRNAs (rniRNAs) are important post-transcriptional regulators involved in many biological processes. We investigated the expression profiles of rniRNAs affected by the histone deacetylase inhibitor, suberoylanilide hydroxamic acid (SAHA), and p53 in the human colon cancer cell line, HCT116 (wt-p53) and its derivative, HCT116 (null-p53). In a microarray assay, 144 of 275 human rniRNAs showed several-fold changes in transcription. Most of these rniRNAs were strongly affected by SAHA, and their expression profiles varied depending on the presence of p53. Thirty-one miRNAs showing the greatest expression changes were selected for target prediction, and genes related to apoptosis (102), cell cycle (38), and differentiation (102) were predicted. Each miRNA had many target genes, and several genes also were targeted by many rniRNAs. Putative p53 upstream binding sites for the miRNAs were determined, and most sites scored >85%, suggesting a high probability of binding. In conclusion, we identified several miRNAs whose expression was affected by both SAHA and p53. Many of the miRNAs showed dramatic changes and were predicted to target many mRNAs. Further studies will be needed to verify these predictions.