Expression of the 17-1A antigen in gastric and gastro-oesophageal junction adenocarcinomas: a potential immunotherapeutic target?
BACKGROUND
A murine monoclonal antibody against the 17-1A epithelial antigen has been shown to be a useful adjuvant therapy in colorectal cancer. Its clinical use could be extended to patients with upper gastrointestinal adenocarcinoma.


OBJECTIVE
To determine the distribution of the antigen in gastric and oesophageal adenocarcinoma.


METHODS
The activity of two monoclonal antibodies active against 17-1A epithelial antigen was studied in gastric and gastro-oesophageal junction adenocarcinomas: fresh frozen tissue from both the carcinoma and adjacent mucosa was stained using immunocytochemistry with a murine monoclonal antibody (17-1A edrecolomab, Glaxo Wellcome); paraffin embedded tissue was stained using the humanised monoclonal antibody 3622W94 (Glaxo Wellcome).


RESULTS
29 of 33 cancers (88%) stained with the murine antibody and 39 of 40 (98%) with the humanised antibody. The degree of staining was greater in well differentiated and moderately differentiated tumours. There was no staining of the normal background gastric or oesophageal mucosa, but areas of intestinal metaplasia stained intensely. The humanised monoclonal 3622W94 antibody produced more intense staining than the murine antibody.


CONCLUSIONS
The high incidence of expression of the 17-1A antigen in patients with gastric and gastro-oesophageal junction adenocarcinomas suggests a potential role for these antibodies as an adjuvant treatment for these common cancers.
Martin
I G
IG
Department of Histopathology, General Infirmary at Leeds, UK. i.g.martin@leeds.ac.uk
Cutts
S G
SG
Birbeck
K
K
Gray
S
S
Quirke
P
P
D000230:Adenocarcinoma / Q000378:metabolism* / Q000628:therapy; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm / Q000378:metabolism*; D004938:Esophageal Neoplasms / Q000378:metabolism* / Q000628:therapy; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007167:Immunotherapy / Q000379:methods; D008297:Male; D008875:Middle Aged; D011230:Precancerous Conditions / Q000378:metabolism; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000628:therapy
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; C050928:carcinoma-associated antigen 17-1A