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: Moorthy P Ponnusamy, Ganesh Venkatraman, Ajay P Singh, Subhash C Chauhan, Sonny L Johansson, Maneesh Jain, Lynnette Smith, John S Davis, Steven W Remmenga, Surinder K Batra
• Journal: Cancer letters (Cancer Lett) Vol. 251 Issue 2 Pg. 247-57 (Jun 28 2007) ISSN: 0304-3835 [Print] Ireland
• PMID: 17210225 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Antibodies, Neoplasm
• Antigens, Neoplasm
• B72.3 antibody
• Glycoproteins
• tumor-associated antigen 72

Topics

• Antibodies, Neoplasm
• Antigens, Neoplasm (metabolism)
• Cell Line, Tumor
• Cell Membrane (metabolism)
• Cytoplasm (metabolism)
• Female
• Glycoproteins (metabolism)
• Humans
• Immunohistochemistry
• Neoplasm Staging
• Ovarian Neoplasms (metabolism, pathology)
• Prognosis