Expression of TAG-72 in ovarian cancer and its correlation with tumor stage and patient prognosis.
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.
Ponnusamy
Moorthy P
MP
Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198-5870, USA.
Venkatraman
Ganesh
G
Singh
Ajay P
AP
Chauhan
Subhash C
SC
Johansson
Sonny L
SL
Jain
Maneesh
M
Smith
Lynnette
L
Davis
John S
JS
Remmenga
Steven W
SW
Batra
Surinder K
SK
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
D000912:Antibodies, Neoplasm; D000951:Antigens, Neoplasm; C091202:B72.3 antibody; D006023:Glycoproteins; C047052:tumor-associated antigen 72