title: Optical anisotropy of toluidine blue-stained transformed cell nuclei.
abstract: Changes in chromatin order with cell transformation were studied in terms of optical anisotropy (birefringence) in toluidine blue-stained NIH 3T3 and Balb/3T3 cells. The transformed NIH 3T3 cell lines used were obtained by transfection with the T24 cell H-ras oncogene and the whole genomic DNA of MCF-7 human breast carcinoma cells. C2PO and PAP2 cell lines were used as representatives of Ha-ras-transformed NIH 3T3 cells with poor and high metastatic ability, respectively. The chromatin of all cells examined exhibited metachromasy and a birefringence of greenish-yellow interference color. The highest birefringence intensity was found in the chromatin granules of the most frequent nuclear phenotype of ras- and MCF-7 DNA-transformed cells, with the exception of the cells with high metastatic ability, in which a faint birefringence was observed. The differences in chromatin birefringence intensity are assumed to indicate differences in chromatin stereoarrangement with cell transformation. In the case of the highly tumorigenic and/or highly metastatic transformants the faint birefringence is assumed to be associated with the heterogeneous and complex physiological processes that may require a relatively less ordered arrangement of the chromatin.
authors.affiliation: Department of Cell Biology, UNICAMP, Campinas, SP, Brazil.
authors.forename: M L
authors.initials: ML
authors.lastname: Mello
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001718:Birefringence; D001943:Breast Neoplasms; D002467:Cell Nucleus / Q000473:pathology / Q000648:ultrastructure*; D002471:Cell Transformation, Neoplastic; D004273:DNA, Neoplasm / Q000008:administration & dosage / Q000378:metabolism*; D011905:Genes, ras; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008815:Mice, Inbred Strains; D014048:Tolonium Chloride; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D004273:DNA, Neoplasm; D014048:Tolonium Chloride