Elevated Expression of Cancer-Associated Proliferating Cell Nuclear Antigen in High-Grade Prostatic Intraepithelial Neoplasia and Prostate Cancer
X Wang, RJ Hickey, LH Malkas, MO Koch, S Zhang, GE Sandusky, DJ Grignon, JN Eble, L Cheng. Indiana University School of Medicine, Indianapolis
Background: Proliferating-cell nuclear antigen (PCNA) plays an important role in DNA replication and repair. Recent studies found that the cancer-associated isoform of PCNA (caPCNA) was present mainly in malignant tissue, such as mammary carcinoma. The expression and potential utility of this marker in prostatic neoplasia is uncertain.
Design: Using a traditional primary Fab2' rabbit anti-caPCNA antibody-HRP conjugated secondary anti-Fab2' antibody format, the expression of the cancer-associated isoform of PCNA (caPCNA) was analyzed in prostate tissue from 94 radical prostatectomy specimens. In each specimen, expression staining was evaluated in benign prostatic epithelium, high-grade prostatic intraepithelial neoplasia, and prostatic adenocarcinoma. The number of positively staining cells was estimated, and the intensity of staining was scored on a scale of 0 to 3+.
Results: Immunohistochemically, the fraction of cells staining positively with caPCNA antibody in prostatic adenocarcinoma (mean: 23%) was significantly higher than that in benign prostatic epithelium (mean: 2%, p < 0.001) or high-grade prostatic intraepithelial neoplasia (mean: 6%, p < 0.05). Moreover, the intensity of the reaction in prostatic adenocarcinoma (mean: 2.9) was significantly higher than that in benign prostatic tissue (mean: 0.7, p<0.001) or high-grade prostatic intraepithelial neoplasia (mean: 2.0, p < 0.001). Benign prostatic epithelium showed only minimal or negative reactions.
Conclusions: These results indicate that increased expression of the cancer-associated isoform of PCNA is common in prostatic adenocarcinoma and may be useful in helping to distinguish prostatic adenocarcinoma from other lesions of prostatic epithelium.
Category: Genitourinary (including renal tumors)
Wednesday, March 24, 2010 9:30 AM
Poster Session V # 103, Wednesday Morning