DIFFERENTIAL NUCLEAR MATRIX-INTERMEDIATE FILAMENT EXPRESSION IN HUMANPROSTATE-CANCER IN RESPECT TO BENIGN PROSTATIC HYPERPLASIA

We have characterized the changes in composition of the nuclear matrix -intermediate filament complex (NM-IF) isolated from prostate cancer ( PCa), compared with benign prostatic hyperplasia (BPH). We prepared th e NM-IF from ten patients undergoing radical retropubic prostectomy; t he benign hyperplastic tissue was obtained from the prostate lobe cont ralateral to the cancer zone. Several quantitative and qualitative cha nges have been identified. Three new proteins of molecular weight 48, 47 and 29 kDa and isoelectric point 6.0, 4.9 and 6.4, respectively, we re detected in PCa, referred to here as P8, P5 and NM-1. P8 was presen t in all ten of the tumors examined, P5 was expressed in 9/10 PCa; con versely, they were present in only one and two BPH, respectively; NM-1 was found in eight tumors out of nine and never in BPH. These protein s are expressed in moderately differentiated malignant cells, suggesti ng that the proteins of the NM-IF complex can be interesting biomarker s for prostate cancer. Immunoblot analysis shows that P8 and P5 protei ns belong to the IF superfamily. This observation, taken together with previous data obtained by our and other groups, suggests that the cha racterization of NM-IF protein changes could also shed light on mechan istic aspects of cancer progression.