Detection of aberrant methylation in fecal DNA as a molecular screening tool for colorectal cancer and precancerous lesions.
OBJECTIVE
To investigate the feasibility of detecting methylated fecal DNA as a screening tool for colorectal carcinoma (CRC) and precancerous lesions.


METHODS
Methylated secreted frizzled-related protein gene 2 (SFRP2), hyperplastic polyposis protein gene (HPP1) and O6-methylguanine-DNA methyltransferase gene (MGMT) in stools from 52 patients with CRC, 35 patients with benign colorectal diseases and 24 normal individuals were analyzed using methylation-specific PCR.


RESULTS
Methylated SFRP2, HPP1 and MGMT were detected in 94.2%, 71.2%, 48.1% of CRC patients and 52.4%, 57.1%, 28.6% of adenoma patients, respectively. The overall prevalence of fecal DNA with at least one methylated gene was 96.2% and 81.8% in patients with CRC and precancerous lesions, respectively. In contrast, only one of the 24 normal individuals revealed methylated DNA. These results indicated a 93.7% sensitivity and a 77.1% specificity of the assay for detecting CRC and precancerous lesions.


CONCLUSIONS
Methylation testing of fecal DNA using a panel of epigenetic markers may be a simple and promising non-invasive screening method for CRC and precancerous lesions.
Huang
Zhao-Hui
ZH
Oncology Institute of Wuxi, The Fourth Affiliated Hospital of Soochow University, 200 Huihe Road, Wuxi 214062, Jiangsu Province, China. hzhwxsy@yahoo.com.cn
Li
Li-Hua
LH
Yang
Fan
F
Wang
Jin-Fu
JF
D000236:Adenoma / Q000175:diagnosis* / Q000235:genetics; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D014408:Biomarkers, Tumor / Q000235:genetics; D002277:Carcinoma / Q000175:diagnosis* / Q000235:genetics; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000235:genetics; D019175:DNA Methylation; D015254:DNA Modification Methylases / Q000235:genetics; D045643:DNA Repair Enzymes / Q000235:genetics; D004273:DNA, Neoplasm / Q000032:analysis* / Q000235:genetics; D005243:Feces / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics; D008875:Middle Aged; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000235:genetics; D011230:Precancerous Conditions / Q000175:diagnosis* / Q000235:genetics; D025521:Tumor Suppressor Proteins / Q000235:genetics; D000094742:Secreted Frizzled-Related Proteins
D014408:Biomarkers, Tumor; D015254:DNA Modification Methylases; D045643:DNA Repair Enzymes; D004273:DNA, Neoplasm; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D025521:Tumor Suppressor Proteins; C109618:SFRP2 protein, human; D000094742:Secreted Frizzled-Related Proteins; C423567:TMEFF2 protein, human; C515491:MGMT protein, human