Analysis of the biological properties and use of comparative genomic hybridization to locate chromosomal aberrations in the human testicular seminomacell line JKT-1 and its highly metastatic cell line JKT-HM

Objective To examine the biological properties, and utility of comparative genomic hybridization (CGH) to locate chromosomal aberrations, in a new hum an testicular seminoma cell line, JKT-1, and a highly metastatic cell line, JKT-HM, developed as an animal model of spontaneous metastasis. Materials and methods JKT-HM was isolated by transplanting cells of JKT-1 i nto the dorsal skin of nude mice, using methods developed previously. The b iological properties of JKT-1 and JKT-HM cells were examined using assays o f cell proliferation and in vitro tumour cell invasion, and the DNA index ( by Bow cytometry). CGH was used to analyse chromosomal aberrations and to d etect chromosomal regions causing metastasis in the testicular seminoma cel l lines. Results The JKT-1 and JKT-HM cells showed no difference in morphology or ce ll proliferation, After transplanting JKT-HM into mice, the cells metastasi zed to the lung and lymph nodes in all five mice by 50 days. The in vitro t umour cell invasion and animal assays suggested potential invasion and meta stasis of JKT-HM. The DNA index was 1.48 for JKT-1 and 1.50 for JKT-HM. CGH analysis revealed Various chromosomal aberrations undetected by examining their karyotypes, e.g. loss of 18p, Yq and gain of Xq, and the technique ha s potential to detect genetic aberrations related to metastasis in this mod el. Conclusions The two cell lines JKT-1 and JKT-HM, and the metastatic animal model used, were useful in studying human testicular seminoma and the metas tatic behaviour of cancer, In addition, CGH was useful for analysing the ch romosomes of two different cell lines derived from the same parent line.