HSP-27 HAS NO DIAGNOSTIC OR PROGNOSTIC-SIGNIFICANCE IN PROSTATE OR BLADDER CANCERS

Heat shock protein 27 (hsp-27) is a cytosol protein of unknown functio n that is concentrated in many estrogen-sensitive normal target organs and is expressed to a varying degree in many tumors, including ductal carcinoma of the breast, malignant fibrous histiocytoma (MFH) of the soft tissues, adenocarcinoma of the prostate, and transitional cell ca rcinoma (TCC) of the urinary bladder. Overexpression of hsp-27 has ind ependent prognostic significance in patients with breast cancer and MF H, but its potential predictive value with prostate and bladder cancer s has not been evaluated. Differential expression of hsp-27 may occur between invasive cancer and host tissue that could aid in diagnosis, a nd varying expression among invasive cancers may have potential progno stic significance that could influence the use of adjuvant therapy. To test these hypotheses, hsp-27 expression was evaluated by immunohisto chemistry in archival formalin-fixed paraffin-embedded sections of pri mary prostate and bladder carcinomas where the outcome of the patient was known. In 36 prostate cancer specimens from patients who had under gone radical prostatectomy (Stages T1, T2; NO; MO), no normal glandula r elements or invasive cancers expressed this protein. In 24 bladder c ancer specimens from patients who had undergone radical cystectomy (St ages T2, T3A, T3B, T4A; NO, N1; MO), 12 (50%) cancers overexpressed th is protein. Hsp-27 did not correlate with degree of histologic differe ntiation, T-stage, nodal status, local recurrence, metastases, or surv ival. From these, observations, we conclude that hsp-27 expression has neither diagnostic nor prognostic significance and will not serve as a predictive biologic marker with these important genitourinary cancer s.