Chromosomal rearrangement in choriocarcinoma cell lines

Malignant trophoblastic cells from four choriocarcinoma cell lines were evaluated in detail using Q, G, and C banding at various passages. The modal chromosome numbers for BeWo, DoSmi, ElFa, and Jar were 73, 71, 77, and 72, respectively. All the four tumor cell lines exhibited extensive chromosomal rearrangements with several consistent marker chromosomes in each. The majority of these markers have not been previously recognized in this malignancy. Rearrangements of chromosomes 1, 7, 9, 10, and 12 were noted in all four cell lines, but abnormalities of chromosomes 1 and 12 were not consistently present in ElFa and Jar, respectively. Telomeric associations were observed in two cell lines involving chromosomes 11 and 21 as well as chromosomes 3 and 12, resulting in two consistent marker chromosomes. A total of 86 breakpoints were involved in the consistent rearrangements observed in all four cell lines. Most of these breakpoints were located on chromosomes 1, 3, 9, 13, 12, 7, and 21, in order of frequency.