Project description:Sage performed on microdissection of Head and Neck tumor, and Head and Neck normal tissue comparative analysis of gene expression profiles of head and neck squamous cell carcinoma and Head and Neck normal tissue
Project description:The differential diagnosis between head & neck squamous cell carcinomas and lung squamous cell carcinomas is often unresolved because the histologic appearance of these two tumor types is similar. In the development of a gene expression profile test (GEP-HN-LS) that distinguishes these 2 cancer types, a collection of poorly differentiated primary and metastatic tumor specimens were used. Here we describe 76 such tumor specimens that were used for validation of GEP-HN-LS. The specimens are either head & neck squamous cell carcinomas or lung squamous cell carcinomas.
Project description:The differential diagnosis between head & neck squamous cell carcinomas and lung squamous cell carcinomas is often unresolved because the histologic appearance of these two tumor types is similar. In the development of a gene expression profile test (GEP-HN-LS) that distinguishes these 2 cancer types, a collection of poorly differentiated primary and metastatic tumor specimens were used. Here we describe 76 such tumor specimens that were used for validation of GEP-HN-LS. The specimens are either head & neck squamous cell carcinomas or lung squamous cell carcinomas. All tissue specimens were formalin fixed paraffin embedded specimens. Gene expression was profiled using Affymetrix GeneChip platform.
Project description:Rap1GAP is a critical tumor suppressor gene that is down-regulated in multiple aggressive cancers such as head and neck squamous cell carcinoma, melanoma and pancreatic cancer. However, the mechanistic basis of rap1GAP down-regulation in cancers is poorly understood. By employing an integrative approach, we demonstrate polycomb-mediated repression of rap1GAP that involves EZH2, a histone methyltransferase in head and neck cancers. We further concomitant down-regulation of rap1GAP in head and neck cancers. EZH2 represses rap1GAP by facilitating the trimethylation of H3K27, a mark of gene repression, and also hypermethylation of rap1GAP promoter. These results provide a conceptual framework involving a microRNA-oncogene-tumor suppressor axis to understand head and neck cancer progression.
