Quantitative fluorescent imaging analysis to study UPD-glucose dehydrogenase as a potential biomarker associated with prostate carcinogenesis

2177 Human UDP-glucose dehydrogenase (UGDH) catalyzes oxidation of UDP-glucose to yield UDP-glucuronic acid,a precursor for glycosaminoglycans and proteoglycans including hyaluronan, promoting prostate cancer (PC) invasion. The goal of this study was to evaluate the UGDH expression in cancerous acini (CA) and normal appearing acini (NAA) of cancer-bearing prostate glands, as a potential complimentary biomarker of PC and/or PC field disease, by quantitative fluorescence imaging analysis (QFIA). Formalin-fixed prostate core biopsies from age-matched cases and controls were labeled with antibody to UGDH and a secondary antibody labeled with fluorescent marker. Stability of QFIA was established by the Leica Fluorescence Microscope and Image ProPlus Software-based system using calibration beads, PC3 cells and benign prostate hyperplasia (BPH) tissue as standards. Quantification of UGDH was validated by reverse phase protein analysis (RPPA) of methacarn fixed tissue using two BPH and eight PC specimens. The validated QFIA was then used to analyze (a) CA and NAA from 33 PC glands and (b) normal acini (NA) from controls (BPH patients). The imaging system showed a stability of the mean pixel intensity (MPI) of standard fluorescent beads and PC3 cells and BPH tissue controls with a variation not excedeed 5%-10%. Adjacent tissue sections assayed by QFIA and RPPA exhibited a strong linear correlation (r=.97) and a correlation of r=.98 for quantification of the UGDH between the methacarn and 10% formalin fixed tissues. The areas under the ROC curve for the NAA samples were 0.68 (95% CI: 0.59-0.83) and 0.71 (95% CI: 0.59-0.83) for CA. At a cut point of 300, the sensitivity was 14% (95% CI: 2-25) with high specificity of 98% (95% CI: 95-100). Significant differences were observed for NA vs. CA, P=0.001; CA vs. NAA, P=0.001 and NAA vs. NA, P=0.001 (paired t test and non-paired t test with Welch correction). These data demonstrate the feasibility of development of a tissue proteomic QFIA method for the quantification of UGDH in prostate core biopsy specimens . UGDH in prostate core biopsy specimens shows promise as a potential complimentary biomarker to beta-catenin for defining individuals with a high risk of PC development. This study was supported by DOD Idea Development Award #DAMD17-02-1-0121, 2002 to 2005, NCI Cancer Center Support Grant P30 CA36727, and a Nebraska Department of Health Institutional LB595 Grant for Cancer And Smoking Disease Research.