Dataset Information

Unique DNA methylation signature in HPV-positive head and neck squamous cell carcinomas

ABSTRACT: Background. Head and neck squamous cell carcinomas (HNSCCs) represent a heterogeneous group of cancers, for which human papilloma virus (HPV) infection is an emerging risk factor. Previous studies showed promoter hypermethylation in HPV(+) oropharyngeal cancers, but only few consistent target genes have been so far described and the evidence of a functional impact on gene expression is still limited. Methods. We performed global and stratified pooled analyses of epigenome-wide data in HNSCCs based on the Illumina HumanMethylation450 bead-array data in order to identify tissue-specific components and common viral epigenetic targets in HPV-associated tumours . Results. We identified novel differentially methylated CpGs and regions associated with viral infection that are independent of the anatomic site. In particular, most hypomethylated regions were characterized by a marked loss of CpG island boundaries, which showed significant correlations with expression of neighbouring genes. Moreover, a subset of only 5 CpGs in few hypomethylated regions predicted HPV status with a high level of specificity in different cohorts. Finally, this signature was a better predictor of survival compared with HPV status determined by viral gene expression by RNA-Sequencing in the TCGA cohort. Conclusions. We identified a novel epigenetic signature of HPV infection in HNSCCs which is independent of the anatomic site, is functionally correlated with gene expression and may be leveraged for improved stratification of prognosis in HNSCCs.

ORGANISM(S): Homo sapiens

PROVIDER: GSE95036 | GEO | 2017/02/18

SECONDARY ACCESSION(S): PRJNA375792

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Introduction: Human Papilloma Virus (HPV) is associated with a subset of head and neck squamous cell carcinoma (HNSCC), between 15% and 35% of HNSCC harboring HPV, almost exclusively of subtype 16. Demographic and exposure differences between HPV-positive (+) and negative (-) HNSCCs suggest that HPV(+) tumors may constitute a subclass with different biology, while clinical differences have also been observed. In this study, gene expression profiles of HPV(+) and (-) tumors were compared to further explore the biological effect of HPV in HNSCC. Methods: Thirty-six HNSCC tumors were analyzed for gene expression using Affymetrix Human 133U Plus 2.0 GeneChip and for HPV using consensus primers for HPV L1, E6 and E7 by PCR and RT-PCR. Results: Eight (22%) of 36 tumors were positive for HPV, all of the HPV 16 subtype, and the HPV positive samples also expressed viral HPV E6 mRNA determined by RT-PCR. Patients with HPV(+) HNSCCs were on average younger than those with HPV(-) tumors (mean age 50.2 vs. 58.7). Statistical analysis using Significance Analysis of Microarrays (SAM) based on HPV status as a supervising parameter resulted in a list of 91 genes that were differentially expressed with statistical significance. Results for a sub-set of these genes were verified by RT-PCR. Genes highly expressed in HPV(+) samples included cell cycle regulators (p16INK4A, p18 and CDK2) and transcription factors (TAF7L, RFC4, RPA2 and TFDP2). The microarray data were also investigated using DIGMap to map genes by chromosomal location. A large number of genes on chromosome 3q24-qter was found to be overrepresented in HPV(+) tumors. Conclusion: The gene expression profile associated with HPV reflects alterations in cell cycle and proliferation signals. Further investigation of differentially expressed genes may reveal the unique pathways in HPV(+) tumors that may explain the different natural history and biological properties of these tumors. These properties may be exploited as a target of novel therapeutic agents in HNSCC treatment. Keywords: HPV, HNSCC, head and neck cancer, human, human papilloma virus

Dataset Information

Unique DNA methylation signature in HPV-positive head and neck squamous cell carcinomas

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure