Immunoprecipitation of nucleosomal DNA is a novel procedure to improve the sensitivity of serum screening for the p16 hypermethylation associated with colon cancer.

Abstract

BACKGROUND:

We developed a novel method of methylation-specific PCR (MSP) using immunoprecipitation with anti-histone antibody (IP-MSP) to efficiently detect serum methylated DNA tightly bound to de-acetylated histones.

MATERIALS AND METHODS:

The detection limit of IP-MSP for p16 methylation was determined with a standard made by cell line (SKCO-1) lysate. p16 methylation of tumor and/or serum of 51 colorectal cancers and 10 adenoma patients, and 10 healthy volunteers was detected with conventional MSP or IP-MSP.

RESULTS:

IP-MSP detected p16 methylation from 0.5pg/mul of the cell lysate. The sensitivity of IP-MSP for detecting serum p16 methylation in 27 patients with tumors characterized by p16 methylation was significantly higher than that with conventional method (81% versus 59%), particularly in Stage II patients (91% versus 45%). IP-MSP detected no p16 hypermethylation in sera of adenoma patients and volunteers.

CONCLUSIONS:

IP-MSP is thus considered to be a promising procedure to detect serum methylated DNA in colorectal cancer patients.

• Authors: Jun Sakamoto, Mikihiro Fujiya, Kotaro Okamoto, Toshie Nata, Yuhei Inaba, Kentaro Moriichi, Hiroki Tanabe, Yusuke Mizukami, Jiro Watari, Toshifumi Ashida, Yutaka Kohgo
• Journal: Cancer epidemiology (Cancer Epidemiol) Vol. 34 Issue 2 Pg. 194-9 (Apr 2010) ISSN: 1877-783X [Electronic] Netherlands
• PMID: 20129840 (Publication Type: Journal Article)

Chemical References

• Biomarkers, Tumor
• DNA, Neoplasm
• Nucleosomes
• DNA

Topics

• Biomarkers, Tumor (blood, genetics)
• Cell Line, Tumor
• Colorectal Neoplasms (blood, chemistry, genetics)
• DNA (genetics)
• DNA Methylation
• DNA, Neoplasm (blood, genetics)
• Female
• Genes, p16
• Humans
• Immunoprecipitation
• Male
• Nucleosomes (genetics)
• Polymerase Chain Reaction (methods)
• Promoter Regions, Genetic