title: Prostate-specific membrane antigen expression in the neovasculature of gastric and colorectal cancers.
abstract: Prostate-specific membrane antigen (PSMA), a type II transmembrane metallo-peptidase highly overexpressed in prostate cancer cells, has been studied as a targeting molecule in prostate cancer. Recently, PSMA has also been found to be expressed in the neovasculature of multiple nonprostatic solid tumors. Because of its unique expression pattern limited to tumor-associated endothelial cells, PSMA may also be an interesting molecule for vascular targeting. In this study, PSMA expression was determined by immunohistochemistry in 119 cases of primary gastric adenocarcinoma, 130 cases of primary colorectal adenocarcinoma, and 24 metastasis of colorectal adenocarcinoma. Expression data were correlated with clinicopathologic information. PSMA expression was detected in tumor-associated neovasculature of 79 (66%) of 119 gastric and 110 (85%) of 130 colorectal carcinomas. Furthermore, the neovasculatures of 16 (84%) of 19 liver and 4 (80%) of 5 nodal metastases from colorectal carcinomas were prostate-specific membrane antigen positive. There was a trend for high-grade tumors to higher PSMA expression (Spearman r = 0.18, P = .046) in colorectal cancers. No association between PSMA expression and overall- or disease-free survival was observed in gastric or colorectal cancers. This study provides the first in-depth look at PSMA expression in gastric and colorectal cancer. Because of its highly tumor-restricted expression and its accessibility to targeted therapy, PSMA represents a promising therapeutic and diagnostic target in colorectal and gastric cancer.
authors.affiliation: Division of Medical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck, Austria. michael.haffner@i-med.ac.at
authors.forename: Michael C
authors.initials: MC
authors.lastname: Haffner
authors.forename: Irmgard E
authors.initials: IE
authors.lastname: Kronberger
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Ross
authors.forename: Christine E
authors.initials: CE
authors.lastname: Sheehan
authors.forename: Matthias
authors.initials: M
authors.lastname: Zitt
authors.forename: Gilbert
authors.initials: G
authors.lastname: Mühlmann
authors.forename: Dietmar
authors.initials: D
authors.lastname: Ofner
authors.forename: Bettina
authors.initials: B
authors.lastname: Zelger
authors.forename: Christian
authors.initials: C
authors.lastname: Ensinger
authors.forename: Ximing J
authors.initials: XJ
authors.lastname: Yang
authors.forename: Stephan
authors.initials: S
authors.lastname: Geley
authors.forename: Raimund
authors.initials: R
authors.lastname: Margreiter
authors.forename: Neil H
authors.initials: NH
authors.lastname: Bander
mesh_terms: D000230:Adenocarcinoma / Q000098:blood supply / Q000378:metabolism*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000954:Antigens, Surface / Q000096:biosynthesis*; D014408:Biomarkers, Tumor / Q000032:analysis; D015179:Colorectal Neoplasms / Q000098:blood supply / Q000378:metabolism*; D005260:Female; D005455:Fluorescent Antibody Technique; D043425:Glutamate Carboxypeptidase II / Q000096:biosynthesis*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D009367:Neoplasm Staging; D009389:Neovascularization, Pathologic / Q000378:metabolism*; D011379:Prognosis; D013274:Stomach Neoplasms / Q000098:blood supply / Q000378:metabolism*
chemical_list: D000954:Antigens, Surface; D014408:Biomarkers, Tumor; C473848:FOLH1 protein, human; D043425:Glutamate Carboxypeptidase II