CHROMOSOME STUDIES ON HUMAN BONE TUMORS IN IN VIVO AND IN VITRO

Abstract

Chromosome studies were made in 8 cases of benign giant-cell tumors and 6 cases of human bone sarcomas. All of the giant-cell tumors showed a sharp chromosome-number mode at 46 with a superficially normal diploid karyotype. The sarcomas were characterized by having aneuploid modal numbers with a rather wide variation ranging from 58 to 92.
Six out of 8 giant-cell tumors were maintained successivelyin culture for a period ranging from 4 months to 3 years. Cells from early subculture passages showed a modal number of 46, with a higher proportion of tetraploid cells than that of the original tumors in vivo. In general, frequencies of polyploid and aneuploid cells increased with the accretion of in vitro generations. Two cell lines of giantcell tumors were successfully maintained in in vitro culture for more than 850 days; they showed a striking morphological change of cells. The modal chromosome number of these two lines fell in a range of hypotriploidy.