p I 6"K4A, p I 5"K4B, and p i 8 proteins are highly specific inhibitors of cyclin-dependent serindthreonine kinase (CDK) activities required for G IS transition in the eukaryotic cell division cycle. Mutations, mainly homozygous deletions, of the CDKN2A (p16"K4A/MTSI) gene have been recently found i
Inactivation of the cyclin-dependent kinase inhibitor 2A (CDKN2A) gene in squamous cell carcinoma of the larynx
β Scribed by Robert Smigiel; Maria Sasiadek; Tomasz Krecicki; David Ramsey; Jozef Jagielski; Nikolaus Blin
- Publisher
- John Wiley and Sons
- Year
- 2004
- Tongue
- English
- Weight
- 226 KB
- Volume
- 39
- Category
- Article
- ISSN
- 0899-1987
- DOI
- 10.1002/mc.20007
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β¦ Synopsis
Abstract
Defects in the system controlling the cell cycle can lead an increased proliferation of cancer cells. The aim of our study was to analyze the relationship between genetic changes leading to inactivation of the CDKN2A gene and subsequent alteration of protein expression in squamous cell cancer of the larynx (SCCL) in connection with the clinical and histopathological course of the disease. Analysis was carried out on DNA isolated from the blood and primary larynx cancer cells of 62 patients. To investigate loss of heterozygosity (LOH), PCR fragment analysis was applied. The size and quantity of fluorescent PCR products were evaluated in an automated sequencer. Specific chemical methylation with sodium bisulfite in a sequential PCR reaction (MSP) was applied to analyze promoter methylation. Cancer tissue sections served to determine the level of protein expression with immunohistochemical (IHC) staining and commercial antibodies. LOH at the CDKN2A locus was observed in 55.35% of the informative cases. Aberrant methylation was found in 37.5% and a decreased level of protein expression observed in 45% of all informative cases. Whenever P16 expression was decreased, LOH and promoter hypermethylation at CDKN2A were observed with a frequency of 73.33% and 80.95%, respectively (Fisher's test, Pβ<β0.005). Sixtyβnine percent of G3 tumors had at least one genetic alteration at CDKN2A, compared with 40.9% of G1 cancers. The results indicate that CDKN2A inactivation played a significant role in the development of squamous cell carcinoma of the larynx. Β© 2004 WileyβLiss, Inc.
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