p57, tumorigenesis, and beckwith-wiedemann syndrome ashley albright
TRANSCRIPT
p57, Tumorigenesis, and Beckwith-Wiedemann Syndrome
Ashley Albright
p57 is a member of the Cip/Kip family of CKIs
• Encoded by CDKN1C• Cyclin/CDK binding domain • PAPA Repeat• QT domain
The ability of p57 to inhibit Cyclin/CDK suggests it is a tumor suppressor, however
p57 levels are high in some cancers
p57 inhibits proliferation by binding and inhibiting CDKs
• G1-S and G2-M transition
• Disruption of CDK/cyclin or PCNA binding region reduces ability of p57 to inhibit proliferation
p57 can suppress or promote apoptosis
• However, other data suggests p57 suppresses pro-apoptotic factors at cell cycle checkpoints
p57 and other Cip/Kip proteins promote cellular migration which leads to tumor
metastasis
p57 homozygous mutants cannot exit the cell cycle, allowing cells to become
over-proliferative
p57 misregulation can lead to cancer via many pathways
• DNA methylation and Histone Modifications
• MicroRNAs• Post-
translational Modification
CDKN1C has been implicated in Beckwith-Wiedemann Syndrome
• 1 in 12,000 newborns• Primarily due to improper imprinting• Classified as an overgrowth syndrome• Susceptible to tumors
BWS patients have a higher risk of developing abnormal tissue growth
References
• "Beckwith-Wiedemann Syndrome." Genetics Home Reference. Accessed March 30, 2015. http://ghr.nlm.nih.gov/condition/beckwith-wiedemann-syndrome.
• Bilodeau, S., et al. "Distinct Developmental Roles of Cell Cycle Inhibitors P57Kip2 and P27Kip1 Distinguish Pituitary Progenitor Cell Cycle Exit from Cell Cycle Reentry of Differentiated Cells." Molecular and Cellular Biology 29, no. 7 (2009): 1895-908.
• Cooper, W., et al. "Molecular Subtypes and Phenotypic Expression of Beckwith–Wiedemann Syndrome." European Journal of Human Genetics 13 (2005): 1025-032
• Denicourt, C., et al. "Cip/Kip Proteins: More than Just CDKs Inhibitors." Genes & Development 18 (2004): 851-55.
• Hatada, I., et al."An Imprinted Gene P57KIP2 Is Mutated in Beckwith–Wiedemann Syndrome." Nature Genetics 14 (1996): 171-73.
• Yan, Y., et al. "Ablation of the CDK Inhibitor P57 Kip2 Results in Increased Apoptosis and Delayed Differentiation during Mouse Development." Genes & Development 11 (1997): 973-83.