Friday 31 August 2007
AIM2 encodes a deduced 344-amino acid protein that contains a conserved sequence domain of approximately 200 amino acids shared with interferon-inducible genes as IFI16 (MIM.147586) and MNDA (MIM.159553) as well as a tyrosine kinase phosphorylation site.
Northern blot analysis revealed expression of a 2-kb AIM2 transcript in spleen, small intestine, and peripheral blood leukocytes as well as a slightly larger transcript in testis. Overexpression of AIM2 reversed the tumorigenic phenotype in a melanoma cell line.
AIM2 belongs to the HIN-200 family of interferon (IFN)-inducible proteins.
Sequencing of the entire coding region of AIM2 revealed a high frequency of frameshift and missense mutations in primary MSI-H colon cancers and cell lines.
Biallelic AIM2 alterations were detected in 8 MSI-H colon tumors and cell lines. In addition, AIM2 promoter hypermethylation conferred insensitivity to IFN-gamma-induced AIM2 expression of three MSI-H colon cancer cell lines.
Inactivation of AIM2 by genetic and epigenetic mechanisms is frequent in MMR-deficient colorectal cancers, thus suggesting that AIM2 is a mutational target relevant for the progression of MSI-H colorectal cancers.
Woerner SM, Kloor M, Schwitalle Y, Youmans H, Doeberitz MV, Gebert J, Dihlmann S. The putative tumor suppressor AIM2 is frequently affected by different genetic alterations in microsatellite unstable colon cancers. Genes Chromosomes Cancer. 2007 Aug 28; PMID: #17726700#
DeYoung, K. L.; Ray, M. E.; Su, Y. A.; Anzick, S. L.; Johnstone, R. W.; Trapani, J. A.; Meltzer, P. S.; Trent, J. M. : Cloning a novel member of the human interferon-inducible gene family associated with control of tumorigenicity in a model of human melanoma. Oncogene 15: 453-457, 1997. PubMed ID : #9242382#