%0 Journal Article
%T A 115-bp MethyLight assay for detection of p16 (CDKN2A) methylation as a diagnostic biomarker in human tissues
%A Jing Zhou
%A Jie Cao
%A Zheming Lu
%A Hongwei Liu
%A Dajun Deng
%J BMC Medical Genetics
%D 2011
%I BioMed Central
%R 10.1186/1471-2350-12-67
%X p16 Methylation was detectable in 75 samples using the classic MethyLight assay. The methylated-p16 positive rate and proportion of methylated-p16 by the MethyLight in MSP-positive samples were higher than those in MSP-negative samples (positive rate: 37/44 vs. 38/58, P=0.035, two-sided; proportion [median]: 0.78 vs. 0.02, P < 0.007). Using the published results of MSP as a golden standard, we found sensitivity, specificity, and accuracy for this MethyLight assay to be 70.5%, 84.5%, and 55.0%, respectively. Because amplicon of the classic MethyLight procedure only partially overlapped with the MSP amplicon, we further designed a 115-bp novel MethyLight assay in which the amplicon on the sense-strand fully overlapped with the MSP amplicon on the antisense-strand. Using the 115-bp MethyLight assay, we observed methylated-p16 in 26 of 44 MSP-positive samples and 2 of 58 MSP-negative ones (P = 0.000). These results were confirmed with clone sequencing. Sensitivity, specificity, and accuracy using the 115-bp MethyLight assay were 59.1%, 98.3%, and 57.4%, respectively. Significant differences in the oral cancer rate were observed during the followup between patients (¡Ý60 years) with and without methylated-p16 as detected by the 115-bp MethyLight assay (6/8 vs. 6/22, P = 0.034, two-sided).The 115-bp MethyLight assay is a useful and practical assay with very high specificity for the detection of p16 methylation clinically.Aberrant methylation of CpG islands is a very stable modification of genomic DNA that often inactivates gene expression pathologically. Methylation of a target CpG island in even 0.1% of a cell population obtained from fixed/frozen tissues or body fluids can be detected readily. The high stability and high sensitivity of detection make DNA methylation one kind of optimal clinical biomarker for the prediction of potential malignancy progression of precancerous lesions, metastasis/recurrence of cancer, and chemo/radio-therapy sensitivity [1].It is well recog
%U http://www.biomedcentral.com/1471-2350/12/67