The p53 tumor suppressor is mutated in at least half of all human cancers, and mice deficient in p53 develop cancer at 100 percent frequency, underscoring the critical role of p53 in preventing tumorigenesis. p53 exerts its tumor suppressive function by sensing cellular stress and inducing cells to undergo either G1 arrest or apoptosis to limit their proliferation. Although the mechanism by which p53 activates G1 arrest is becoming clearer, there is considerably less understanding of the mechanism by which it induces apoptosis. To identify genes specifically activated during apoptosis, we performed a subtractive hybridization screen in which G1-arrested cell RNA populations were subtracted from apoptotic cell RNA populations. In this screen, we isolated a novel gene, PERP (p53 apoptosis effector related to PMP-22), that is preferentially expressed in apoptotic cells. PERP encodes a novel tetraspan membrane protein related to the PMP-22/gas3 protein commonly implicated in human hereditary peripheral neuropathies such as Charcot Marie Tooth disease. PERP is induced during p53-dependent but not p53- independent apoptosis, and expression of PERP in cells is sufficient to induce cell death, together suggesting it is a strong candidate mediator of p53 function in apoptosis. The role of PERP in p53 function will be investigated in this proposal. To conclusively determine the importance of PERP in p53 function, a PERP knockout mouse has been generated. Through analysis of various cell types derived from PERP-deficient mice, the importance of PERP for p53-mediated apoptosis will be defined. Furthermore, by studying PERP null mice, the role of PERP in normal development as well as in p53-mediated tumor suppression will be elucidated. If there is an embryonic lethal phenotype of the PERP null mice, we will utilize a conditional PERP knockout mouse we have also generated to specifically inactivate PERP in certain tissues and determine its role as a tumor suppressor in those contexts. In addition, the mechanism by which PERP induces cell death will be examined through cell biological approaches, to clarify the link between p53 and the apoptotic machinery. Together, these approaches will define the role of PERP in mediating p53 function in apoptosis and tumor suppression. As activation of the p53-dependent apoptotic response is thought to determine the response of at least some tumor types to radiotherapy and chemotherapy, an understanding of the pathway also has important clinical implications, both for prognosis and therapy.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA093665-02
Application #
6620628
Study Section
Cell Development and Function Integrated Review Group (CDF)
Program Officer
Blair, Donald G
Project Start
2002-01-01
Project End
2006-12-31
Budget Start
2003-01-01
Budget End
2003-12-31
Support Year
2
Fiscal Year
2003
Total Cost
$287,605
Indirect Cost
Name
Stanford University
Department
Radiation-Diagnostic/Oncology
Type
Schools of Medicine
DUNS #
009214214
City
Stanford
State
CA
Country
United States
Zip Code
94305
Dusek, Rachel L; Bascom, Jamie L; Vogel, Hannes et al. (2012) Deficiency of the p53/p63 target Perp alters mammary gland homeostasis and promotes cancer. Breast Cancer Res 14:R65
Baron, Sylvain; Hoang, Anabel; Vogel, Hannes et al. (2012) Unimpaired skin carcinogenesis in Desmoglein 3 knockout mice. PLoS One 7:e50024
Dusek, Rachel L; Attardi, Laura D (2011) Desmosomes: new perpetrators in tumour suppression. Nat Rev Cancer 11:317-23
Beaudry, Veronica G; Ihrie, Rebecca A; Jacobs, Suzanne B R et al. (2010) Loss of the desmosomal component perp impairs wound healing in vivo. Dermatol Res Pract 2010:759731
Beaudry, Veronica G; Jiang, Dadi; Dusek, Rachel L et al. (2010) Loss of the p53/p63 regulated desmosomal protein Perp promotes tumorigenesis. PLoS Genet 6:e1001168
Beaudry, Veronica G; Pathak, Navneeta; Koster, Maranke I et al. (2009) Differential PERP regulation by TP63 mutants provides insight into AEC pathogenesis. Am J Med Genet A 149A:1952-7
Ihrie, R A; Bronson, R T; Attardi, L D (2006) Adult mice lacking the p53/p63 target gene Perp are not predisposed to spontaneous tumorigenesis but display features of ectodermal dysplasia syndromes. Cell Death Differ 13:1614-8
Marques, Michelle R; Ihrie, Rebecca A; Horner, Jennifer S et al. (2006) The requirement for perp in postnatal viability and epithelial integrity reflects an intrinsic role in stratified epithelia. J Invest Dermatol 126:69-73
Ihrie, Rebecca A; Attardi, Laura D (2005) A new Perp in the lineup: linking p63 and desmosomal adhesion. Cell Cycle 4:873-6
Ihrie, Rebecca A; Marques, Michelle R; Nguyen, Bichchau T et al. (2005) Perp is a p63-regulated gene essential for epithelial integrity. Cell 120:843-56

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