title: Expression of TAG-72 in ovarian cancer and its correlation with tumor stage and patient prognosis.
abstract: Tumor associated glycoprotein-72 (TAG-72), a pancarcinoma antigen, was initially identified in cancer tissues by its immunoreactivity to a monoclonal antibody B72.3. In this study, we have analyzed the expression and localization profiles of TAG-72 in ovarian cancer tissue samples of different stages and histological subtypes by immunohistochemistry using a second generation high affinity monoclonal antibody CC49. We have also studied the expression of TAG-72 in ovarian cancer cell lines by confocal microscopy and immunoblot analyses. A correlation between TAG-72 expression and localization with patients' prognosis was also analyzed using Kaplan-Meier analysis. Eighty eight percent of the ovarian cancer tissue samples (n=43) showed immunoreactivity with CC49 antibody. The expression of TAG-72 in advanced stage cancer tissues (mean composite score=3.7) was significantly higher (p=0.035) compared to the early stage tumors (mean composite score=2.3). However, no significant correlation of TAG-72 was observed with histological tumor types. A marginal correlation of TAG-72 staining with patients' survival was observed. Interestingly, the membrane localization of TAG-72 in tumors was significantly (p=0.0082) associated to the poor clinical outcome, while cytoplasmic staining was correlated significantly to a better prognosis (p=0.0051). Immunoblot analysis demonstrated the expression of TAG-72 in three ovarian cancer cell lines (OVCAR3, SB247 and COV362.4). In conclusion, the tumor-specific expression of TAG-72 and its association with disease stage indicate its potential as a marker for effective disease management and targeted cancer therapy.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198-5870, USA.
authors.forename: Moorthy P
authors.initials: MP
authors.lastname: Ponnusamy
authors.forename: Ganesh
authors.initials: G
authors.lastname: Venkatraman
authors.forename: Ajay P
authors.initials: AP
authors.lastname: Singh
authors.forename: Subhash C
authors.initials: SC
authors.lastname: Chauhan
authors.forename: Sonny L
authors.initials: SL
authors.lastname: Johansson
authors.forename: Maneesh
authors.initials: M
authors.lastname: Jain
authors.forename: Lynnette
authors.initials: L
authors.lastname: Smith
authors.forename: John S
authors.initials: JS
authors.lastname: Davis
authors.forename: Steven W
authors.initials: SW
authors.lastname: Remmenga
authors.forename: Surinder K
authors.initials: SK
authors.lastname: Batra
mesh_terms: D000912:Antibodies, Neoplasm; D000951:Antigens, Neoplasm / Q000378:metabolism*; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D005260:Female; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000378:metabolism* / Q000473:pathology; D011379:Prognosis
chemical_list: D000912:Antibodies, Neoplasm; D000951:Antigens, Neoplasm; C091202:B72.3 antibody; D006023:Glycoproteins; C047052:tumor-associated antigen 72