THE PROGNOSTIC VALUE OF CD44 ISOFORMS IN PROSTATE-CANCER PATIENTS TREATED BY RADICAL PROSTATECTOMY

CD44 forms a group of transmembranous glycoproteins formed by alternat ive splicing of a single mRNA, The expression of v6 exon-containing va riants correlates with metastasis and poor prognosis in a number of ma lignancies, The distribution and prognostic value of CD44s, CD44v5, an d CD44v6 were studied immunohistochemically in the radical prostatecto my specimens of 97 patients with prostate cancer and in 12 lymph node metastases, The mean follow-up period was 84 months, The percentage of CD44-immunoreactive cells was scored semiquantitatively, CD44 mRNA ex pression was studied in nine prostate cancer and eight benign prostati c hyperplasia (BPH) samples by reverse transcriptase-PCR, Benign prost atic glands almost always expressed CD44s, CD44v6, and, at a lower int ensity, CD44v5, CD44 scores decreased from low- to high-grade prostati c intraepithelial neoplasia, CD44s, CD44v5, and CD44v6 were expressed in 86, 23, and 69% of the adenocarcinomas, respectively, Gleason sum s core (GSS) and pT stage were correlated inversely with CD44s and CD44v 6 scores, CD44 was not found in the lymph node metastatic tumor cells, At the mRNA level, 89% of the tumors and all BPH samples expressed CD 44s, CD44v6-v10 mRNA was present in 44 and 75% of the tumors and BPH s amples, respectively, Loss of CD44s and CD44v6 predicted an adverse pr ognosis at univariate analysis, The independent prognosticators identi fied by multivariate analysis were: GSS, pT stage, and CD44s for clini cal progression; GSS and CD44s for prostate-specific antigen progressi on; and GSS for tumor-specific survival, Loss of CD44s expression in p rostate adenocarcinoma predicts a poor prognosis, independent of stage and grade.