P15ink4b is a Critical Tumour Suppressor in the Absence of P16ink4a.
From: Division of Molecular Genetics and Centre for Biomedical Genetics, The Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands.
Nature
- Publish Date: Aug 2007
- ISSN: 1476-4687
- Volume: 448
- Issue: 7156
- Pages: 943-6
- Medium: Internet
- Language: English
- Citation (JAMA): Krimpenfort Paul, Ijpenberg Annemieke, Song Ji-Ying, et al. P15ink4b is a Critical Tumour Suppressor in the Absence of P16ink4a.. Nature Aug 2007;448:943-6
Abstract
The CDKN2b-CDKN2a locus on chromosome 9p21 in human (chromosome 4 in mouse) is frequently lost in cancer. The locus encodes three cell cycle inhibitory proteins: p15INK4b encoded by CDKN2b, p16INK4a encoded by CDKN2a and p14ARF (p19Arf in mice) encoded by an alternative reading frame of CDKN2a (ref. 1). Whereas the tumour suppressor functions for p16INK4a and p14ARF have been firmly established, the role of p15INK4b remains ambiguous. However, many 9p21 deletions also remove CDKN2b, so we hypothesized a synergistic effect of the combined deficiency for p15INK4b, p14ARF and p16INK4a. Here we report that mice deficient for all three open reading frames (Cdkn2ab-/-) are more tumour-prone and develop a wider spectrum of tumours than Cdkn2a mutant mice, with a preponderance of skin tumours and soft tissue sarcomas (for example, mesothelioma) frequently composed of mixed cell types and often showing biphasic differentiation. Cdkn2ab-/- mouse embryonic fibroblasts (MEFs) are substantially more sensitive to oncogenic transformation than Cdkn2a mutant MEFs. Under conditions of stress, p15Ink4b protein levels are significantly elevated in MEFs deficient for p16Ink4a. Our data indicate that p15Ink4b can fulfil a critical backup function for p16Ink4a and provide an explanation for the frequent loss of the complete CDKN2b-CDKN2a locus in human tumours.
Mesh Headings (Keywords): Animals, Cell Cycle, Cell Differentiation, Cell Line, Transformed, Cell Proliferation, Cell Transformation, Neoplastic, Cells, Cultured, Cyclin-Dependent Kinase Inhibitor p15, Cyclin-Dependent Kinase Inhibitor p16, Embryo, Mammalian, Fibroblasts, Gene Deletion, Genes, Tumor Suppressor, Humans, Mice, Oncogenes, Open Reading Frames, RNA, Messenger, Sarcoma, Skin Neoplasms
Check for Full Text / PubMed Unique Identifier (PMID): 17713536
This abstract is part of PubMed, a service of the U.S. National Library of Medicine. PubMed includes more than 17 million citations from MEDLINE and other life science journals for biomedical articles. See Copyright and Disclaimers.
Linked medical terms appearing on this page are added by Healia to help readers find more information and are not part of the original PubMed document.
The data herein was last updated on July 8th, 2008 and may not reflect the most current and accurate data available from NLM.