Epigenome analysis in HPV(-) and HPV(+) squamous cell carcinoma cell lines

Human papillomavirus (HPV)-associated head and neck cancers (HNSCCs) have a distinct risk profile and appreciate a prognostic advantage compared to HPV-negative HNSCC. Promoter hypermethylation has been widely recognized as an important mechanism in the progression of HNSCC, but the extent to which this mechanism is consistent between HPV(+) and HPV(-) tumors is unknown. To assess the genome-wide methylation changes in HPV(+) and HPV(-) tumors, we analyzed DNA methylation and expression patterns in two HPV(+) and two HPV(-) cell lines. HPV(+) tumors have overall higher DNA methylation in genic and LINE1 regions than HPV(-) tumors, and polycomb repressive complex 2 (PRC2) targets tend to be much more highly methylated in HPV(+) cells. Bisulphite-converted DNA from 4 squamous cell carcinoma (SCC) cell lines were hybridized to the Illumina Infinium 27k Human Methylation Beadchip.