Genetic heterogeneity of prostatic carcinoma-derived cell lines as emphasized by DNA fingerprinting.

To investigate genetic heterogeneity during in vitro cultivation of human prostatic carcinomas following radical prostatectomy we performed DNA fingerprinting using the digoxygenin-labeled probes (GACA)4 and (GTG)5. DNA was isolated from fresh material stemming from different areas within one tumor and from cell cultures of the same material. The patterns which were obtained by the nucleolar organizer region (NOR)-specific probe (GACA)4 exhibit only a few prominent low molecular mass bands and no differences were observed between any of the tumors analyzed so far. Changes in the fingerprint pattern occurred between cell cultures derived from different areas within one tumor when the DNA was cleaved by HaeIII and signals detected with the (GTG)5 probe. The "area-specific" pattern was stable during several subcultivations of these cell lines, indicating genetic stability of these prostatic carcinoma cells in vitro. Thus individual cell lines derived from radical prostatectomy seem to represent a biological system very close to the situation in vivo.