title: Analyses of the APC and TGF-beta type II receptor genes, and microsatellite instability in mucosal colorectal carcinomas.
abstract: APC and transforming growth factor-beta type II receptor (TGF-beta RII) gene mutations, and microsatellite instability have been found in sporadic colorectal carcinomas. To clarify further the early alterations in colorectal carcinogenesis, we investigated these genetic changes in 23 protruding- and 24 superficial-type mucosal colorectal carcinomas. TGF-beta RII gene mutations and microsatellite instability were rarely found in these lesions. Nevertheless, APC was mutated in 16 of the 47 (34.0%) mucosal colorectal carcinomas and was significantly more frequently mutated in protruding- (I) and superficial elevated-type (IIa) (14/32, 43.8%) than in other superficial-type (IIa+IIc, IIb, IIc, and IIc+IIa) (2/ 15, 13.3%) mucosal colorectal carcinomas (P < 0.04). These results indicate that the APC gene may be involved from the beginning in the tumorigenesis of many early colorectal carcinomas, particularly of the protruding and superficial elevated types. However, there might be a distinct pathway for other superficial-type colorectal carcinomas, possibly not involving APC as an initial step of tumorigenesis.
authors.affiliation: First Department of Surgery, Tokyo Medical and Dental University School of Medicine.
authors.forename: O K
authors.initials: OK
authors.lastname: Yagi
authors.forename: Y
authors.initials: Y
authors.lastname: Akiyama
authors.forename: Y
authors.initials: Y
authors.lastname: Ohkura
authors.forename: S
authors.initials: S
authors.lastname: Ban
authors.forename: M
authors.initials: M
authors.lastname: Endo
authors.forename: K
authors.initials: K
authors.lastname: Saitoh
authors.forename: Y
authors.initials: Y
authors.lastname: Yuasa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D002277:Carcinoma / Q000145:classification / Q000235:genetics* / Q000473:pathology; D002471:Cell Transformation, Neoplastic / Q000235:genetics; D015179:Colorectal Neoplasms / Q000145:classification / Q000235:genetics* / Q000473:pathology; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000235:genetics*; D005260:Female; D017491:Genes, APC; D011905:Genes, ras; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology*; D008297:Male; D018895:Microsatellite Repeats; D008875:Middle Aged; D008957:Models, Genetic; D009361:Neoplasm Invasiveness; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D017346:Protein Serine-Threonine Kinases; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000235:genetics*
chemical_list: D004273:DNA, Neoplasm; D018125:Receptors, Transforming Growth Factor beta; D017346:Protein Serine-Threonine Kinases; D000077294:Receptor, Transforming Growth Factor-beta Type II