INTRACELLULAR LEVELS OF SGP-2 (CLUSTERIN) CORRELATE WITH TUMOR GRADE IN PROSTATE-CANCER

Our previous observations in LNCaP cells bl vitro demonstrated an asso ciation between apoptotic cell death resistance and SGP-2 (Clusterin) overexpression. Accordingly, we hypothesized that high levels of cellu lar SGP-2 would aid in identifying biologically aggressive prostate ca ncer cells with unique survival advantages, To test this hypothesis, 4 0 archival radical prostatectomy and/or biopsy specimens of varying gr ades of prostate cancer were subjected to immunohistochemical SGP-2 st aining, The resulting epithelial stains were quantified subjectively o n a scale of 1-3 by four independent observers. Benign prostatic epith elial cells from young donors served as controls and showed a consiste ntly weak staining intensity, In contrast, prostate cancer specimens s howed varying degrees of staining intensity that correlated with a Gle ason pattern (P = 0.006), This correlation supports the hypothesis tha t protection from apoptotic death may account, in part, for biological ly aggressive tumor behavior.