EXPRESSION OF P27(KIP1) IN PROSTATIC ADENOCARCINOMA

p27(kip1) (p27) protein is an inhibitor of cyclin and cyclin-dependent : kinase complexes and prevents progression of cells fi um GL to the S phase of the cell cycle, p27 might have tumor suppressor activity, an d decreased p27 expression is associated with aggressive tumor behavio r in several human malignancies. The object of this study was to evalu ate p27 expression in prostatic adenocarcinoma treated by radical pros tatectomy and to assess its association with numerous morphologic and clinical features, One hundred thirty-eight prostatic adenocarcinomas were evaluated for p27 expression by quantifying nuclear immunohistoch emical staining. p27 expression was tested fur association with patien t age, family history of prostate cancer, preoperative serum prostate- specific antigen level, Gleason score, extraprostatic extension, semin al vesicle involvement, lymph node metastases, tumor-node-metastasis s tage, DNA ploidy by flow cytometric analysis, and subclinical biochemi cal failure, p27 expression was analyzed as a continuous variable, and we also classified the tumors as low expressors (< 50% of cells p27 p ositive) or high expressors (> 50% of cells p27 positive) for comparis on. Patients with adenocarcinomas that exhibited low p27 expression ha d higher mean Gleason scores than did high expressors (7 vs. 6.2, resp ectively; P = .002). Low p27 expression correlated with positive surgi cal margins (P = .05), seminal vesicle involvement (P = .007), lymph n ode metastasis (P = .03), and aneuploid cancers (P = .003), but it did not correlate with subclinical biochemical failure, p27 expression co rrelated with a number of prognostic morphologic features in prostatic adenocarcinoma, and the evaluation of p27 expression might provide ad ditional prognostic information.