## Abstract Giant cell tumors are heterogeneous tumors consisting of multinucleated giant cells, fibroblastβlike stromal cells and mononuclear histiocytes. The stromal cells have been identified as the neoplastic cell population, which promotes the recruitment of histiocytes and the formation of gi
Silencing of the UCHL1 gene in human colorectal and ovarian cancers
β Scribed by Eriko Okochi-Takada; Kazuyuki Nakazawa; Mika Wakabayashi; Akiko Mori; Shizue Ichimura; Toshiharu Yasugi; Toshikazu Ushijima
- Publisher
- John Wiley and Sons
- Year
- 2006
- Tongue
- French
- Weight
- 599 KB
- Volume
- 119
- Category
- Article
- ISSN
- 0020-7136
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
Aberrant DNA methylation is associated with many types of human cancers. To identify genes silenced in human colorectal cancers, we performed a microarray analysis for genes whose expression was induced by treatment of HCT116 human colon cancer cells with a demethylating agent, 5βazaβ2β²βdeoxycitidine (5βazaβdC). Seven known genes were identified as being upregulated (β₯8βfold) and expressed at more than twice as high as the average level. Among these was the UCHL1 gene (also known as PGP9.5), which is involved in regulation of cellular ubiquitin levels. A dense CpG island in its promoter region was completely methylated in HCT116 cells, and no mRNA was detected. 5βAzaβdC treatment of HCT116 cells induced doseβdependent demethylation of the CpG island, and restored UCHL1 mRNA and protein expression. UCHL1 silencing was observed in 11 of 12 human colorectal cancer cell lines, and its methylation was detected in 8 of 17 primary colorectal cancers. Further, UCHL1 silencing was observed in 6 of 13 ovarian cancer cell lines, and its methylation was detected in 1 of 17 primary ovarian cancers. These results showed that UCHL1 is inactivated in human colorectal and ovarian cancers by its promoter methylation, and suggest that disturbance of cellular ubiquitin levels is present. Β© 2006 WileyβLiss, Inc.
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