RAP1 Signaling in Prostate Cancer Progression
CS Moreno, VM Henderson, W Zhou, D Williams, N Laycock, H Kitayama, AO Osunkoya. Emory University School of Medicine, Atlanta, GA; Winship Cancer Institute, Atlanta, GA; Kyoto University Graduate School of Medicine, Kyoto, Japan
Background: RAP1 proteins are small G-protein regulators of E-cadherin cell-cell junctions and integrin-mediated cell-matrix adhesions. The role of RAP1 in prostate cancer progression is not well understood, but it has been linked to its regulation of integrins and cellular proliferation. RAP1 GTPase-activation Proteins (GAP) or RAP1GAP facilitates hydrolysis of GTP to GDP and inactivation of RAP1 proteins.
Design: Tissue microarrays (TMA) were constructed from 73 patients who were treated for prostate cancer (PCa) with radical prostatectomy as monotherapy. Their demographic, treatment and long-term clinical outcome data were obtained. TMA sections were stained with H&E and RAP1GAP antibody. Staining was scored on a four level scale (0 = no staining, 1+ = weak staining, 2+ = moderate staining, 3+ = intense staining). The findings were correlated with pathologic features. Significance of correlation with Gleason score was determined using a two-tailed Spearman's rho rank correlation test.
Results: RAP1GAP antibody staining was more intense in the PCa tissues compared to normal tissues, and the staining intensity was significantly correlated with Gleason score (p = 0.0004).
Conclusions: Changes in RAP1GAP expression are significantly correlated with Gleason score, suggesting that reduced RAP1 signals may play a role in metastatic progression of prostate cancer.
Category: Genitourinary (including renal tumors)
Wednesday, March 11, 2009 1:00 PM
Poster Session VI # 118, Wednesday Afternoon