Abstract
1 Cancer Therapeutics Laboratory, Discipline of Medicine, University of Adelaide, Australia
2 Signal Transduction Laboratory, Queensland Institute for Medical Research, Australia
3 Discipline of Surgery, Basil Hetzel Institute, University of Adelaide, Australia
4 p53Lab, Immunos, Agency for Science, Technology and Research, Singapore
* Denotes Equal Contribution
Received: December 21, 2011; Accepted: December 23, 2011; Published: December 25, 2011;
Keywords: mutant p53, p63, secretome, invasion
Correspondence:
Paul Neilsen, email:
Abstract
Mutations in the TP53 gene commonly result in the expression of a full-length protein that drives cancer cell invasion and metastasis. Herein, we have deciphered the global landscape of transcriptional regulation by mutant p53 through the application of a panel of isogenic H1299 derivatives with inducible expression of several common cancer-associated p53 mutants. We found that the ability of mutant p53 to alter the transcriptional profile of cancer cells is remarkably conserved across different p53 mutants. The mutant p53 transcriptional landscape was nested within a small subset of wild-type p53 responsive genes, suggesting that the oncogenic properties of mutant p53 are conferred by retaining its ability to regulate a defined set of p53 target genes. These mutant p53 target genes were shown to converge upon a p63 signalling axis. Both mutant p53 and wild-type p63 were co-recruited to the promoters of these target genes, thus providing a molecular basis for their selective regulation by mutant p53. We demonstrate that mutant p53 manipulates the gene expression pattern of cancer cells to facilitate invasion through the release of a pro-invasive secretome into the tumor microenvironment. Collectively, this study provides mechanistic insight into the complex nature of transcriptional regulation by mutant p53 and implicates a role for tumor-derived p53 mutations in the manipulation of the cancer cell secretome.