title: Gamma-amino-butyric acid immunoreactivity in intramucosal colonic tumors.
abstract: OBJECTIVE
  The level of gamma-amino-butyric acid (GABA) is reported to be increased in colon cancer. Moreover, data suggests that GABA plays a role in the proliferation or maturation of some types of cells. We examined the expression of GABA in intramucosal colonic tumors to clarify the relation between GABA and the degree of atypia.
  
  
  METHODS
  Paraffin sections were prepared from 56 protruded-type colonic neoplasms, which were classified as intramucosal adenocarcinoma (AC), adenoma with severe atypia (ASA), or adenoma with mild to moderate atypia (AMA). Expression of GABA was investigated immunohistochemically, and GABA immunoreactivity was compared to the staining patterns of carcinoembryonic antigen (CEA) and cancer-associated antigen (CA19-9) which were classified into three categories.
  
  
  RESULTS
  Intense GABA immunoreactivity was observed in 73.7%, 54.6%, 13.3%, and 5.4% of AC, ASA, AMA, and normal mucosa specimens, respectively. Kendall's correlation coefficient between GABA immunoreactivity and the degree of atypia was 0.447. Strong, positive CEA staining (pattern 3) was observed in 57.9%, 36.3%, and 13.3% of AC, ASA, and AMA specimens, respectively. Strong, positive CA19-9 staining was observed: 26.3%, 9.1% and 0%, respectively. In AC and ASA, the proportion of glands with strong GABA immunoreactivity was greater than the proportion of glands that were strongly positive for CA19-9.
  
  
  CONCLUSIONS
  GABA may be useful as a tumor marker in combination with other tumor markers such as CEA and CA19-9.
authors.affiliation: Department of Anatomy, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Maemura
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Yamauchi
authors.forename: Hana
authors.initials: H
authors.lastname: Hayasaki
authors.forename: Kiyoto
authors.initials: K
authors.lastname: Kanbara
authors.forename: Takumi
authors.initials: T
authors.lastname: Tamayama
authors.forename: Ichiro
authors.initials: I
authors.lastname: Hirata
authors.forename: Masahito
authors.initials: M
authors.lastname: Watanabe
mesh_terms: D000230:Adenocarcinoma / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism*; D000236:Adenoma / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism*; D003110:Colonic Neoplasms / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism*; D012720:Severity of Illness Index; D005680:gamma-Aminobutyric Acid / Q000032:analysis / Q000096:biosynthesis*
chemical_list: D005680:gamma-Aminobutyric Acid