title: In vitro changes of the nuclear AgNORs pattern induced by RNA inhibitors and 5-fluorouracil in human breast cancer cells, MCF-7 and HBC-4.
abstract: The morphological changes of argyrophilic nucleolar organizer regions (AgNORs) were studied in two human breast cancer cell lines, MCF-7 and HBC-4. Treatment with an RNA polymerase inhibitor (actinomycin D) reduced the size of AgNORs and increased the number of AgNORs. Messenger RNA polymerase inhibitor (alpha-amanitin) also increased the number of AgNORs. However, translational blocking agents closely related to ribosomal RNA (cycloheximide and anisomycin) caused a decrease in the number of AgNORs, which seemed to fuse to an aggregate around the nucleolus and formed a single large spherical AgNOR in the final stage. These changes were observed typically when cells were treated with 5-fluorouracil or 5-fluorouridine. These morphological changes in the AgNORs pattern, AgNORs aggregation, might reflect certain damage in ribosomal RNA.
authors.affiliation: First Department of Surgery, Kobe University School of Medicine, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Furuya
authors.forename: K
authors.initials: K
authors.lastname: Yamamoto
authors.forename: N
authors.initials: N
authors.lastname: Kohno
authors.forename: T
authors.initials: T
authors.lastname: Hamaoka
authors.forename: H
authors.initials: H
authors.lastname: Ono
authors.forename: Y
authors.initials: Y
authors.lastname: Kuroda
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D002452:Cell Count / Q000187:drug effects; D003609:Dactinomycin / Q000494:pharmacology; D005472:Fluorouracil / Q000494:pharmacology*; D006801:Humans; D019384:Nucleic Acid Synthesis Inhibitors / Q000494:pharmacology*; D009697:Nucleolus Organizer Region / Q000187:drug effects* / Q000378:metabolism; D016622:Silver Staining; D014407:Tumor Cells, Cultured / Q000166:cytology / Q000187:drug effects / Q000378:metabolism
chemical_list: D000964:Antimetabolites, Antineoplastic; D019384:Nucleic Acid Synthesis Inhibitors; D003609:Dactinomycin; D005472:Fluorouracil