C-Terminal Portion of Group 3 POTEs Antigen Correlates with Progression of Prostate Cancer
Xinchun Zhou, Zhi He, Samantha Redfield, Kathryn Brown, Steven Bigler. University of Mississippi Medical Center, Jackson
Background: POTEs, containing 3 domains and encoded by POTE gene family (expressed in prostate, ovary, testis and placenta) have been reported to be expressed in both normal and malignant prostate tissues. Whether the expression levels and which domain of POTEs corrlate with the progression of prostate cancer is unknown. The aim of this study is to investigate the association of the expression levels of C- and N-terminals of group 3 POTEs with the progression of prostate cancer.
Design: Immunohistochemistry (IHC) for both C- and N-terminal antibodies was performed on tissue microarrays (TMA) including 260 specimens, which were divided into four groups: benign (34), PIN (36), primary prostate cancer (155) and metastatic prostate cancer (25). A semi quantitative IHC score, calculated by multiplying area score (0-3) and density score (0-3), was used as the expression level and compared among and between the groups.
Results: IHC signals were found in nucleoli for C-terminal and in cytoplasm for N-terminal. The IHC score for C-terminal was the highest in metastatic prostate cancer (7.5), which was dramatically higher than that in primary prostate cancer (4.3, p=2.4 x 10-5), PIN (2.5, p=3.0x10-7) and benign prostate (1.6, p=1x10-7).
Increasing in the number and irregularity of nucleoli stained for C-terminal correlated with progression of prostate cancer.
The IHC score for N-terminal was the lowest in the benign prostate (2.1), which was significantly lower than that in PIN (4.9, p=3.3x10-6), primary prostate cancer (4.6, p=1.6x10-6) and metastatic prostate cancer (5.7, p=2x10-7); however, there was no significant difference among PIN, primary and metastatic prostate cancer. IHC scores for both C- and N-terminals correlated with the Gleason's grade in primary prostate cancer.
Conclusions: C-terminal portion of Group 3 POTEs is a nucleolar marker associated with progression of prostate cancer, from PIN to primary prostate cancer, to metastatic prostate cancer.
Category: Genitourinary (including renal tumors)
Tuesday, March 20, 2012 1:00 PM
Poster Session IV # 110, Tuesday Afternoon