Distinct tumorigenic pathways within hereditary nonpolyposis colorectal cancer

Gene expression profiling has discriminated between sporadic microsatellite instable (MSI) and microsatellite stable (MSS) colorectal cancers (CRCs), whereas the expression pattern of familial colorectal cancer type X (FCCTX) and Lynch syndrome (LS) associated CRCs remain largely unknown. The purpose of this study is to use gene expression profiling of formalin-fixed paraffin-embedded (FFPE) tumor specimens from FCCTX, LS and sporadic CRC as a control to detect expression patterns and to identify signaling pathways differing between FCCTX and LS tumors. RNA extracted from 132 FFPE specimens (40 FCCTX, 42 LS, 50 sporadic) were profiled for differential gene expression by the whole genome cDNA-mediated annealing, selection, extension, and ligation (WG-DASL) assay containing 18626 genes.