Apoptosis-stimulating protein of p53 (ASPP2) heterozygous mice are tumor-prone and have attenuated cellular damage-response thresholds.

Publication

Apoptosis-stimulating protein of p53 (ASPP2) heterozygous mice are tumor-prone and have attenuated cellular damage-response thresholds.

Journal Paper/Review - Feb 26, 2009

Kampa-Schittenhelm Kerstin, Acoba Jared D, Chen Dexi, Gay Joel, Lee Hunjoo, Beemer Kelly, Padiernos Emerson, Boonmark Nataya, Zhu Zhiyi, Fan Alice C, Bailey Alexis S, Fleming William H, Corless Christopher L, Felsher Dean W, Naumovski Louie, Lopez Charles Darin

Citation

Kampa-Schittenhelm K, Acoba J, Chen D, Gay J, Lee H, Beemer K, Padiernos E, Boonmark N, Zhu Z, Fan A, Bailey A, Fleming W, Corless C, Felsher D, Naumovski L, Lopez C. Apoptosis-stimulating protein of p53 (ASPP2) heterozygous mice are tumor-prone and have attenuated cellular damage-response thresholds. Proc Natl Acad Sci U S A 2009; 106:4390-5.

Type

Journal Paper/Review (English)

Journal

Proc Natl Acad Sci U S A 2009; 106

Publication Date

Feb 26, 2009

Issn Electronic

1091-6490

Pages

4390-5

Brief description/objective

The expression of ASPP2 (53BP2L), a proapoptotic member of a family of p53-binding proteins, is frequently suppressed in many human cancers. Accumulating evidence suggests that ASPP2 inhibits tumor growth; however, the mechanisms by which ASPP2 suppresses tumor formation remain to be clarified. To study this, we targeted the ASPP2 allele in a mouse by replacing exons 10-17 with a neoR gene. ASPP2(-/-) mice were not viable because of an early embryonic lethal event. Although ASPP2(+/-) mice appeared developmentally normal, they displayed an increased incidence of a variety of spontaneous tumors as they aged. Moreover, gamma-irradiated 6-week-old ASPP2(+/-) mice developed an increased incidence of high-grade T cell lymphomas of thymic origin compared with ASPP2(+/+) mice. Primary thymocytes derived from ASPP2(+/-) mice exhibited an attenuated apoptotic response to gamma-irradiation compared with ASPP2(+/+) thymocytes. Additionally, ASPP2(+/-) primary mouse embryonic fibroblasts demonstrated a defective G(0)/G(1) cell cycle checkpoint after gamma-irradiation. Our results demonstrate that ASPP2 is a haploinsufficient tumor suppressor and, importantly, open new avenues for investigation into the mechanisms by which disruption of ASPP2 pathways could play a role in tumorigenesis and response to therapy.