SPECIFIC CYTOGENETIC ABERRATIONS IN 2 NOVEL HUMAN PROSTATIC CELL-LINES IMMORTALIZED BY HUMAN-PAPILLOMAVIRUS TYPE-18 DNA

Using chromosome banding and fluorescence in situ hybridization (FISH) with painting probes, sequential cytogenetic analysis was performed o f two novel prostrate cell lines, PZ-HPV-7 and CA-HPV-10, established by human papillomavirus (HPV) 18 DNA transformation. PZ-HPV-7 originat es from a normal diploid prostrate epithelial cell strain. PZ-HPV-7 pr ogressed from an initial diploid to a hypertetraploid chromosome numbe r with a relative gain of chromosomes 5 and 20 (7 to 8 copies each). S tructural changes were limited; 3p- (2 copies), 3q- (1 copy), and poss ibly a der(16p;12q). CA-HPV-10 originates from an epithelial cell stra in derived from a high-grade human prostrate cancer specimen, which sh owed several karyotypic abnormalities including an extra Y chromosome and double minutes (dmin). In early passage the karyotype of CA-HPV-10 appeared unstable with a decreasing number of cells exhibiting dmin. In late passage the dmin were replaced by a large homogenously stainin g region (hsr) on 9p+ marker. The hsr was shown by FISH to be of chrom osome 1 origin. The modal number was mainly hypertriploid (72, range 6 9 to 75). Loss of Y was remarkable (0 to 1 copy). Consistent markers i ncluded two copies each of del(1)(q12q31) and der(9)t(1;9)(?;p22), and one der(11)t(4;11)(?;q21). HPV type 18 genomic integration sites were identified on 1p for PZ-HPV-7 and on the 9p+ marker for CA-HPV-10. In conclusion, both PZ-HPV-7 and CA-HPV-10 showed clonal cytogenetic cha nges. These two cell lins constitute a novel in vitro model to study t he mechanisms involved in human prostrate carcino-genesis. (C) 1997 El sevier Science Inc., 1997.