title: Tumorigenicity of human lymphoblastoid cell lines, acquired during in vitro culture and associated with chromosome gains.
abstract: Tumorigenicity of human lymphoma and lymphoblastoid B-cell lines was assessed by their ability to form growing and transplantable masses on subcutaneous inoculation into neonatally thymectomized, Ara-C-protected, total-body-irradiated mice. By these criteria, 12 lines of known malignant origin were tumorigenic, 11 lymphoblastoid lines, tested after less than one year of in vitro growth, were non-tumorigenic and 8/18 long-established lymphoblastoid lines produced transplantable tumours. All of the long-established lines had acquired karyotypic changes on prolonged culture, the predominant characteristic being a gain of whole chromosomes or of major chromosome segments. None showed the classical 8:14 translocation associated with Burkitt's lymphoma. Comparisons with nontumorigenic precursors (recovered from liquid nitrogen storage) and with other non-tumorigenic but chromosomally abnormal, lymphoblastoid lines suggest that imbalance of the dosage of genes carried on chromosomes 7,8 and 9 may be important in determining the tumorigenic phenotype.
mesh_terms: D000483:Alleles; D000818:Animals; D002051:Burkitt Lymphoma / Q000209:etiology / Q000235:genetics / Q000648:ultrastructure; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000648:ultrastructure*; D002478:Cells, Cultured; D002869:Chromosome Aberrations; D005260:Female; D006801:Humans; D007621:Karyotyping; D008214:Lymphocytes / Q000648:ultrastructure*; D008297:Male; D008677:Metaphase; D051379:Mice; D008808:Mice, Inbred CBA; D009368:Neoplasm Transplantation; D010641:Phenotype; D010954:Plasmacytoma / Q000209:etiology / Q000235:genetics / Q000648:ultrastructure; D014178:Translocation, Genetic