DNA-containing cytoplasmic bridges in a human breast cancer cell line, MX-1: morphological markers of a highly mobile cell type?
We have used a CREST anti-centromere serum and a DNA-specific fluorescent dye to study the composition of extended cytoplasmic bridges between interphase cells of a human carcinoma cell line, MX-1, grown on coverslips. Under natural conditions, approximately 8% of the cells possessed cytoplasmic bridges up to 60 microns long. Elongated extensions from the cell surface were also observed and were interpreted as severed cytoplasmic bridges. The bridges were extremely slender throughout most of their lengths and could not be properly resolved by phase-contrast microscopy. Staining with a DNA-specific fluorescent dye revealed, however, the presence of a thin DNA thread. This finding strongly suggests that the bridges arise during mitosis through faults in chromosome segregation. The bridges persist and most probably elongate, when the cells separate from one another after completion of mitosis. Some bridges showed also highly fluorescent DNA masses, which were detected by a CREST anti-centromere serum. Thus, a subset of the cytoplasmic bridges contained centromeres. The DNA-containing bridges between carcinoma cells in culture signal continuous rearrangements of the karyotype at a relatively high rate. The presence of extended cytoplasmic bridges between the cells could be a morphological marker for highly mobile tumor cell types and has, therefore, diagnostic value.
Wolf
K W
KW
Institute of Anatomy, University of Lübeck, Germany.
Mentzel
M
M
Mendoza
A S
AS
D000328:Adult; D001323:Autoantibodies / Q000276:immunology; D001943:Breast Neoplasms / Q000737:chemistry / Q000473:pathology*; D002277:Carcinoma / Q000737:chemistry / Q000473:pathology*; D002455:Cell Division; D002503:Centromere / Q000276:immunology; D003593:Cytoplasm / Q000737:chemistry* / Q000648:ultrastructure; D004273:DNA, Neoplasm / Q000032:analysis*; D005260:Female; D006801:Humans; D007106:Immune Sera; D013692:Telophase; D014407:Tumor Cells, Cultured / Q000648:ultrastructure
D001323:Autoantibodies; D004273:DNA, Neoplasm; D007106:Immune Sera