ALTERED EXPRESSION OF CD44 IN HUMAN PROSTATE-CANCER DURING PROGRESSION

There is a great need for markers that distinguish slowly progressive from rapidly progressive prostate cancers in paraffin-embedded tissues . CD44, an adhesion molecule that has been useful for the prediction o f prognosis in some other cancers, has not been described in prostate cancer. The expression of CD44 was investigated with the monoclonal an tibody GKW.A3 in prostate cancer in formalin-fixed, paraffin-embedded tissue sections of(1) whole prostates from 50 patients with 74 prostat e cancers; and (2) lymph node metastases from 14 patients. Sixty perce nt of primary prostate cancers expressed CD44 moderately to strongly. No metastases expressed CD44 moderately to strongly; only 14% of metas tases expressed even low levels of immunohistochemically detectable CD 44. There is a difference between primary and metastatic prostate canc er (P < .0006) in the expression of CD44 and an inverse correlation (P < .05) between histological differentiation (Gleason grade) and the e xpression of CD44. The magnitude of the differential expression of CD4 4 in primary and metastatic prostate cancers suggests it should be inv estigated as an indicator of prognosis in a large prospective study.