title: [Genomic instability analysis in hereditary cancer syndrome].
abstract: The discovery of microsatellite instability (MSI) and its association to hereditary nonpolyposis colorectal cancer (HNPCC) in 1993 gave rise to a new criterion in tumor biology. By using five microsatellite markers, colorectal carcinomas (CRC) may be classified either as high frequency-MSI (MSI-H) if two or more of the five markers show instability, or as low frequency-MSI (MSI-L)/microsatellite stable (MSS) if one or less shows instability. MSI-H tumors which comprise about 15% of total CRC show distinctive clinicopathologic features: proximal colon location, mucinous and undifferentiated histology, presence of tumor-infiltrating lymphocytes, and a less aggressive clinical course. Mismatch repair gene mutations, transcription loss of a mismatch repair gene associated with promoter region hypermethylation, or loss of imprinting have been proposed as some of the causes for MSI.
authors.affiliation: Department of Pathology, Osaka University Graduate School of Medicine.
authors.forename: Y
authors.initials: Y
authors.lastname: Tomita
authors.forename: K
authors.initials: K
authors.lastname: Aozasa
mesh_terms: D002874:Chromosome Mapping; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000235:genetics; D004260:DNA Repair / Q000235:genetics; D004261:DNA Replication / Q000235:genetics; D006801:Humans; D008745:Methylation; D018895:Microsatellite Repeats / Q000235:genetics; D009154:Mutation; D011401:Promoter Regions, Genetic; D014158:Transcription, Genetic / Q000235:genetics