Abstract |
Recent clinical trials on patients with glioblastoma revealed that O6-Methylguanine-DNA methyltransferase (MGMT) methylation status significantly predicts patient's response to alkylating agents. In this study, we sought to develop and validate a quantitative MGMT methylation assay using pyrosequencing on glioblastoma. We quantified promoter methylation of MGMT using pyrosequencing on paraffin-embedded fine needle aspiration biopsy tissues from 43 glioblastoma. Using a 10% cutoff, MGMT methylation was identified in 37% cases of glioblastoma and 0% of the non-neoplastic epileptic tissue. Methylation of any individual CpG island in MGMT promoter ranged between 33% and 95%, with a mean of 65%. By a serial dilution of genomic DNA of a homogenously methylated cancer cell line with an unmethylated cell line, the analytical sensitivity is at 5% for pyrosequencing to detect MGMT methylation. The minimal amount of genomic DNA required is 100 ng (approximately 3,000 cells) in small fine needle biopsy specimens. Compared with methylation-specific PCR, pyrosequencing is comparably sensitive, relatively specific, and also provides quantitative information for each CpG methylation.
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Authors | Hao Xie, Raymond Tubbs, Bin Yang |
Journal | International journal of clinical and experimental pathology
(Int J Clin Exp Pathol)
Vol. 8
Issue 2
Pg. 1790-6
( 2015)
ISSN: 1936-2625 [Electronic] United States |
PMID | 25973069
(Publication Type: Journal Article)
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Chemical References |
- Tumor Suppressor Proteins
- DNA Modification Methylases
- MGMT protein, human
- DNA Repair Enzymes
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Topics |
- Biopsy, Fine-Needle
- Brain Neoplasms
(enzymology, genetics, pathology)
- Case-Control Studies
- Cell Line, Tumor
- CpG Islands
- DNA Methylation
- DNA Modification Methylases
(genetics)
- DNA Repair Enzymes
(genetics)
- Glioblastoma
(enzymology, genetics, pathology)
- Humans
- Paraffin Embedding
- Promoter Regions, Genetic
- Sequence Analysis, DNA
(methods)
- Tumor Suppressor Proteins
(genetics)
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