Somatic mutations and altered expression of the candidate tumor suppressors CSNK1 epsilon, DLG1, and EDD/hHYD in mammary ductal carcinoma
| Autor: | Tannin J, Fuja, Fritz, Lin, Kathryn E, Osann, Peter J, Bryant |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
Ubiquitin-Protein Ligases
Carcinoma Ductal Breast Molecular Sequence Data Loss of Heterozygosity Membrane Proteins Proteins Breast Neoplasms DNA Neoplasm Discs Large Homolog 1 Protein Case-Control Studies Mutation Humans Female Genes Tumor Suppressor Amino Acid Sequence Casein Kinases Protein Kinases Adaptor Proteins Signal Transducing |
| Zdroj: | Cancer research. 64(3) |
| ISSN: | 0008-5472 |
| Popis: | We report somatic mutations in three genes (CSNK1 epsilon, encoding the Ser/Thr kinase casein kinase I epsilon; DLG1, encoding a membrane-associated putative scaffolding protein; and EDD/hHYD, encoding a progestin induced putative ubiquitin-protein ligase) in mammary ductal carcinoma. These genes were suspected of playing a role in cancer because loss-of-function mutations in their Drosophila homologues cause excess tissue growth. Using DNA from 82 laser-microdissected tumor samples, followed by microsatellite analysis, denaturing HPLC and direct sequencing, we found multiple somatic point mutations in all three genes, and these mutations showed significant association with loss of heterozygosity of closely linked polymorphic microsatellite markers. For CSNK1 epsilon and DLG1, most of the mutations affected highly conserved residues, some were found repetitively in different patients, and no synonymous mutations were found, indicating that the observed mutations were selected in tumors and may be functionally significant. Immunohistochemical reactivity of each protein was reduced in poorly differentiated tumors, and there was a positive association between altered protein reactivity, loss of heterozygosity, and somatic mutations. There was a statistically significant association of hDlg staining with p53 and Ki67 reactivity, whereas CSK1 epsilon and EDD/hHYD staining levels were associated with progesterone receptor status. The results provide strong indications for a role of all three genes in mammary ductal carcinoma. They also justify additional studies of the functional significance of the changes, as well as a search for additional changes in these and other genes identified from studies on model systems. |
| Databáze: | OpenAIRE |
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