GENE AMPLIFICATIONS IN ADVANCED-STAGE HUMAN PROSTATE-CANCER

Gene amplification is a model of proto-oncogene alterations occasional ly observed in human tumors. This amplification can, in some cases, ha ve prognostic value (N-myc in neuroblastoma, c-erbB2 and int-2 in brea st cancer, etc.). Amplifications of the proto-oncogenes c-myc, c-erbB2 and int-2 have not yet been report in prostate adenocarcinoma, which, like breast cancer, is hormone dependent. We sought amplifications of these three proto-oncogenes by means of Southern blotting in 15 human prostate adenocarcinoma specimens, most of which were advanced (7 sta ge C and 6 stage D1 or D2). We confirmed the lack of c-myc and c-erbB2 amplification, regardless of the stage, in contrast to the case of br east cancer. Int-2 amplification was observed in one advanced tumor wi th bone metastases, out of a total of six stage D tumors. The precise frequency of int-2 amplification and its role in prostate carcinogenes is remain to be determined.