Global DNA Methylation: Uncommon Event in Oral Lichenoid Disease [Illumina GoldenGate Methylation Cancer Panel I array]

Purpose: Accumulating evidence indicates aberrant DNA methylation is closely related to oral carcinogenesis, and it has been shown that methylation changes might be used as prognostic biomarker in oral squamous cell carcinoma. Oral lichenoid disease (OLD) is the most common oral potentially malignant disorder in our region. In this study, we have performed a wide DNA methylation study of a series of oral lichenoid disease in order to assess the relevance of DNA methylation changes in this premalignant disorder. Experimental Design: Discovery phase utilized the Illumina Golden Gate Cancer Panel I in 51 OLD and 6 control samples. The differently methylated loci and the global DNA methylation surrogate LINE-1, were further validated in an independent sample set consisting in 160 OLD and 65 controls. Results: DNA methylation profiles of the OLD showed only minor significant differences when compared to controls. Conclusions: In summary, our data indicates that the frequency of aberrant DNA alteration is very low in OLD, which support the low rate of malignization of this oral potentially malignant disorder. Bisulphite-converted DNA from the 51 oral lichenoid disease samples and 6 control samples were hybridised to the Illumina GoldenGate Methylation Cancer Panel I.