Quantitative multiplex methylation-specific PCR assay for the detection of promoter hypermethylation in multiple genes in breast cancer.
If detected early, breast cancer is eminently curable. To detect breast cancer in samples with little cellularity, a high level of sensitivity is needed. Tumor-specific promoter hypermethylation has provided such a valuable tool for detection of cancer cells in biological samples. To accurately assess promoter hypermethylation for many genes simultaneously in small samples, we developed a novel method, quantitative multiplex-methylation-specific PCR (QM-MSP). QM-MSP is highly sensitive (1 in 10(4)-10(5) copies of DNA) and linear over 5 orders of magnitude. For RASSF1A, TWIST, Cyclin D2, and HIN1, we observed significant differences in both the degree (P < 0.003) and incidence (P < 0.02) of hypermethylation between normal and malignant breast tissues. Evaluation of the cumulative hypermethylation of the four genes within each sample revealed a high level of sensitivity (84%) and specificity (89%) of detection of methylation. We demonstrate the application of this technique for detecting hypermethylated RASSF1A, TWIST, Cyclin D2, HIN1, and RARB in 50-1000 epithelial cells collected from breast ducts during endoscopy or by lavage. Such an approach could be used in a variety of small samples derived from different tissues, with these or different biomarkers to enhance detection of malignancy.
Fackler
Mary Jo
MJ
Breast Cancer Program, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21231-1000, USA.
McVeigh
Megan
M
Mehrotra
Jyoti
J
Blum
Marissa A
MA
Lange
Julie
J
Lapides
Amanda
A
Garrett
Elizabeth
E
Argani
Pedram
P
Sukumar
Saraswati
S
D000199:Actins / Q000235:genetics; D001940:Breast / Q000378:metabolism / Q000502:physiology; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism; D044584:Carcinoma, Ductal / Q000235:genetics / Q000378:metabolism; D019175:DNA Methylation; D017931:DNA Primers; D004273:DNA, Neoplasm / Q000032:analysis / Q000235:genetics; D005260:Female; D005784:Gene Amplification; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods*; D011401:Promoter Regions, Genetic; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013431:Sulfates / Q000737:chemistry
D000199:Actins; D017931:DNA Primers; D004273:DNA, Neoplasm; D013431:Sulfates; C012036:sodium sulfate