title: Phenotype-genotype correlation: challenge of intestinal-type adenocarcinoma of the nasal cavity and paranasal sinuses.
abstract: BACKGROUND
  Intestinal-type adenocarcinoma (ITAC) of the nasal cavity and paranasal sinuses shows microscopic features indistinguishable from colorectal cancer. Our aim was to verify whether the morphologic resemblances mirror genetic profile similarities.
  
  
  METHODS
  Twenty consecutive surgically treated ITAC cases, previously investigated for p16(INK4a) and TP53, were investigated for hMLH1, hMSH2, and beta-catenin immunoreactivity, and for adenomatous polyposis coli (APC), K-ras, and BRAF gene mutations.
  
  
  RESULTS
  One case was immunonegative for both hMLH1 and hMSH2, and 12 tumors (40%) revealed a strong beta-catenin overexpression. No BRAF and APC truncating mutations were identified, whereas K-ras mutations were detected in 9 ITACs (50%).
  
  
  CONCLUSIONS
  Our data confirm the phenotypic similarities at the genetic level between colorectal cancer and ITACs showing deregulation of K-Ras/BRAF and loss of heterozygosity (LOH) of chromosome 18q. By contrast, both frequency rate and type of inactivation of the APC-beta-catenin pathway differ in the 2 tumors, suggesting different gatekeeper events in the early development of ITAC (p16(INK4a) and TP53) and colorectal cancer (APC).
authors.affiliation: Department of Experimental Oncology, Istituto Nazionale per lo Studio e la Cura dei Tumori, Via Venezian 1, 20133 Milan, Italy.
authors.forename: Milo
authors.initials: M
authors.lastname: Frattini
authors.forename: Federica
authors.initials: F
authors.lastname: Perrone
authors.forename: Simona
authors.initials: S
authors.lastname: Suardi
authors.forename: Debora
authors.initials: D
authors.lastname: Balestra
authors.forename: Stefano
authors.initials: S
authors.lastname: Caramuta
authors.forename: Federica
authors.initials: F
authors.lastname: Colombo
authors.forename: Lisa
authors.initials: L
authors.lastname: Licitra
authors.forename: Giulio
authors.initials: G
authors.lastname: Cantù
authors.forename: Marco A
authors.initials: MA
authors.lastname: Pierotti
authors.forename: Silvana
authors.initials: S
authors.lastname: Pilotti
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000230:Adenocarcinoma / Q000235:genetics*; D025601:Adenomatous Polyposis Coli Protein / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics; D015179:Colorectal Neoplasms / Q000235:genetics; D053843:DNA Mismatch Repair; D015972:Gene Expression Regulation, Neoplastic; D011905:Genes, ras / Q000235:genetics; D005838:Genotype; D006801:Humans; D019656:Loss of Heterozygosity; D000070957:MutL Protein Homolog 1; D051718:MutS Homolog 2 Protein / Q000235:genetics; D009154:Mutation; D009296:Nasal Cavity; D009669:Nose Neoplasms / Q000235:genetics*; D009687:Nuclear Proteins / Q000235:genetics; D010255:Paranasal Sinus Neoplasms / Q000235:genetics*; D010641:Phenotype; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics; D051176:beta Catenin / Q000235:genetics
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D025601:Adenomatous Polyposis Coli Protein; D002352:Carrier Proteins; C501486:MLH1 protein, human; D009687:Nuclear Proteins; D051176:beta Catenin; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf; C497172:MSH2 protein, human; D000070957:MutL Protein Homolog 1; D051718:MutS Homolog 2 Protein