title: Localization of nerve fibers in colonic polyps, adenomas, and adenocarcinomas by immunocytochemical staining for PGP 9.5.
abstract: BACKGROUND
  PGP 9.5 is a cytoplasmic protein and is a specific marker for neurites and neurons.
  
  
  OBJECTIVE
  Using anti-PGP 9.5, this study aimed to localize nerve fibers in normal colons, polyps, adenomas and adenocarcinomas.
  
  
  METHODS
  Colonic polyps, adenomas and T(1) to T(3) adenocarcinomas with adjacent normal colon were immunostained for PGP 9.5 using rabbit anti-PGP 9.5.
  
  
  RESULTS
  In normal colon, numerous nerve fibers were localized in inner and outer muscles, from which submucosa and lamina propria were innervated. In hyperplastic polyps and tubular adenomas, the stalk revealed Meissner's plexus and large-diameter nerve fibers, and fine nerve fibers innervated abundantly in lamina propria of hyperplastic polyps and small tubular adenomas. In villous adenomas, large-diameter nerve fibers and Meissner's plexus were localized in the stalk whereas a few or no fine nerve fibers were localized in fine stroma. In adenocarcinomas, more fine fibers were localized in submucosal stroma adjacent to the invading carcinoma in T(1) carcinomas but there were no nerve fibers in the midst of tumors in T(2) and T(3) carcinomas. There were focally and sporadically increased nerve fibers adjacent to invading cancer nests in 5 of 8 T(2) cases. In T(3) carcinomas, fragmented Auerbach's plexus were noted in cancer-invaded colonic muscles and there were no increased fine nerve fibers in the cancer-invaded subserosa in the majority of cases. PGP 9.5 immunostaining revealed tumor-associated neurogenesis in submucosa but no obviously increased nerve fibers within cancer-invaded muscles.
  
  
  CONCLUSIONS
  This lack of tumor-associated neurogenesis supports insidious and often silent clinical presentation of colonic carcinomas until invading through the colonic wall to adjacent organs.
authors.affiliation: Department of Pathology and Oregon National Primate Center, Oregon Health and Science University, Portland, OR, USA. tomitat@ohsu.edu
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Tomita
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism*; D000236:Adenoma / Q000378:metabolism* / Q000473:pathology*; D003106:Colon / Q000294:innervation*; D003110:Colonic Neoplasms / Q000378:metabolism* / Q000473:pathology; D003111:Colonic Polyps / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000378:metabolism; D009361:Neoplasm Invasiveness; D009412:Nerve Fibers / Q000378:metabolism*; D043222:Ubiquitin Thiolesterase
chemical_list: D043222:Ubiquitin Thiolesterase; C496976:Uchl1 protein, mouse