title: Double-minute chromatin bodies in HL-60 leukemia cells sensitive and resistant to differentiation inducing agents.
abstract: We studied the chromosome characteristics of HL-60 promyelocytic leukemia cells sensitive and resistant to differentiation inducing agents (DI). The karyotypic analysis of sensitive (HL-60 S) and resistant (HL-60 R) cells revealed the presence of identical chromosome abnormalities such as loss of chromosomes 5, 9, 10, 14, 16, 17 and X; and gain of chromosome 18. HL-60 S and HL-60 R cells also share five common markers. The difference between the two cell lines consisted essentially of the loss of an unidentifiable chromosome segment in the HL-60 R cell line. In addition, the two sublines showed marked differences in the content of double-minute chromatin bodies (DM), which were abundant in HL-60 S but rarely found in HL-60 R cells. Contrary to a previous report by others, there was no evidence of chromosome rearrangement of the DM as homogeneously stained regions (HSR) or abnormally banding regions (ABR) in the resistant HL-60 R cells. The presence of DM as an expression of gene amplification may be of relevance in the determination of susceptibility of HL-60 cells to DI.
mesh_terms: D002454:Cell Differentiation; D002869:Chromosome Aberrations; D002872:Chromosome Deletion; D004351:Drug Resistance; D005819:Genetic Markers; D006801:Humans; D007951:Leukemia, Myeloid / Q000235:genetics*; D014407:Tumor Cells, Cultured
chemical_list: D005819:Genetic Markers