Distinct DNA methylation profiles in ovarian serous neoplasms and their implications in ovarian carcinogenesis.
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ABSTRACT: Objective
The purpose of this study was to analyze DNA methylation profiles among different types of ovarian serous neoplasm, which is a task that has not been performed.Study design
The Illumina beads array (Illumina Inc, San Diego, CA) was used to profile DNA methylation in enriched tumor cells that had been isolated from 75 benign and malignant serous tumor tissues and 6 tumor-associated stromal cell cultures.Results
We found significantly fewer hypermethylated genes in high-grade serous carcinomas than in low-grade serous carcinoma and borderline tumors, which in turn had fewer hypermethylated genes than serous cystadenoma. Unsupervised analysis identified that serous cystadenoma, serous borderline tumor, and low-grade serous carcinomas tightly clustered together and were clearly different from high-grade serous carcinomas. We also performed supervised analysis to identify differentially methylated genes that may contribute to group separation.Conclusion
The findings support the view that low-grade and high-grade serous carcinomas are distinctly different with low-grade, but not high-grade, serous carcinomas that are related to serous borderline tumor and cystadenoma.
SUBMITTER: Shih IeM
PROVIDER: S-EPMC2993872 | biostudies-literature | 2010 Dec
REPOSITORIES: biostudies-literature
Publications
Distinct DNA methylation profiles in ovarian serous neoplasms and their implications in ovarian carcinogenesis.
Shih Ie-Ming IeM Chen Li L Wang Chen C CC Gu Jinghua J Davidson Ben B Cope Leslie L Kurman Robert J RJ Xuan Jianhua J Wang Tian-Li TL
American journal of obstetrics and gynecology 20101020 6
<h4>Objective</h4>The purpose of this study was to analyze DNA methylation profiles among different types of ovarian serous neoplasm, which is a task that has not been performed.<h4>Study design</h4>The Illumina beads array (Illumina Inc, San Diego, CA) was used to profile DNA methylation in enriched tumor cells that had been isolated from 75 benign and malignant serous tumor tissues and 6 tumor-associated stromal cell cultures.<h4>Results</h4>We found significantly fewer hypermethylated genes i ...[more]
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