Contamination of human melanoma cell lines by mouse L cells

A cytogenetic study of eight human melanoma cell lines

Eight cell lines established originally at the Queensland Institute of Medical Research from human malignant melanoma explants have been studied by means of cytogenetic techniques. All showed abnormalities characteristic for each individual line and consisting of marker chromosomes and of changes in ploidy due to the addition of extra copies of normal chromosomes. Repeat cultures of some lines after one or two years contained most of the markers which had characterized the original samples; additional chromosome abnormalities were also found. An anlysis of the break points concerned in the production of markers showed preferential involvement of chromosomes 1 and 5, with a prevalence of centromeric breaks on No. 1. These findings add further weight to the evidence suggesting that changes in chromosome 1 may be of special significance in the pathogenesis of some solid tumours.

Human malignant melanoma cell lines

A series of 10 cell lines established from human malignant melanomas is described. The morphology varied but, in general, was epithelioid. Five produced visible melanin in culture but others produced melanin precursors. All lines were aneuploid and each had a distinctive human karyotype. One line appeared not to have the same sex as the patient but its karyotype was distinct from that of other lines.