SUPPRESSION OF INVASIVE ABILITY OF HIGHLY METASTATIC RAT PROSTATE-CANCER BY INTRODUCTION OF HUMAN-CHROMOSOME-8

BACKGROUND. Introduction of human chromosome 8 to a highly metastatic subline (AT6.2) from the Dunning R-3327 rat prostate cancer resulted i n suppression of metastatic ability of the resultant microcell hybrids (AT6.2-8 clones) [12]. The present study has been performed to clarif y which step of metastasis was suppressed in the microcell hybrids. ME THODS. Northern blot analysis of E-cadherin and alpha-catenin, in vitr o invasion assay, and intra-venous metastasis assay by injection of tu mor cells into the lateral tail vein of nude mice were performed. RESU LTS. No detectable expressions of either E-cadherin or alpha-catenin w ere found in either AT6.2 parental or AT6.2-8 microcell hybrid clones. In the invasion assay, invasiveness of AT6.2-8 hybrid clones was less than that of the AT6.2 parental clone. In the intravenous metastasis assay, no significant differences in the number of lung metastases wer e observed among these cell lines. CONCLUSIONS. Introduction of human chromosome 8 to AT6.2 cells shows suppression of invasiveness and no s uppression of cell dissociation or process after entry into blood circ ulation. This suggests that human chromosome 8 contains suppressor gen e(s) for the invasive ability of prostate cancer. (C) 1997 Wiley-Liss, Inc.