Transcription profiling of human MCF7 time-series upon RITA treatment.

ABSTRACT: Targeting “oncogene addiction” is a promising strategy for anti-cancer therapy. Here, we report a potent inhibition of crucial oncogenes by p53 upon reactivation with small molecule RITA in vitro and in vivo. RITA-activated p53 unleashes transcriptional repression of anti-apoptotic proteins Mcl-1, Bcl-2, MAP4, and survivin, blocks Akt pathway on several levels and downregulates c-Myc, cyclin E and B-catenin. p53 ablates c-Myc expression via several mechanisms at transcriptional and posttranscriptional level. We show that transrepression of oncogenes correlated with higher level of p53 bound to chromatin-bound p53 than transactivation of pro-apoptotic targets. Inhibition of oncogenes by p53 reduces the cell’s ability to buffer pro-apoptotic signals and elicits robust apoptosis. Our study highlights the role of transcriptional repression for p53-mediated tumor suppression. Experiment Overall Design: Breast carcinoma cell-line MCF7 was treated with the small-molecule p53 activator RITA for 2h, 8h, 16h and 24h.

ORGANISM(S): Homo sapiens

SUBMITTER: Martin Enge 

PROVIDER: E-GEOD-13291 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress