Koos Boeve

169 Methylation biomarkers for the detection of tumor DNA in saliva Supplementary data 2. DNA methylation levels of seven OSCC specific markers in saliva and tumor tissues of OSCC patients. Differences in methylation level of the markers between DNA isolated of saliva (saliva patients), fresh frozen (FF tissue) and formalin fixed paraffin embedded tissue (FFPE tissue) of oral squamous cell carcinoma (OSCC) patients. Methylation levels on the x-axis are defined as the average DNA quantity of the gene of interest divided by the average DNA quantity of ACTB and then multiplied by 10,000. Saliva and tumor samples from the same patient are connected by a continuous line in the figure. Tumors were defined as methylated if methylation was present in FFPE or FF tumor tissue. Differences between saliva, FF or FFPE were compared using the Wilcoxon rank test, only significant differences (p < 0.050) are shown. Abbreviations: FF, fresh frozen; FFPE, formalin fixed paraffin embedded.