title: Effect of estradiol and tamoxifen on the anchorage-independent growth of the subpopulations derived from MCF-7 breast carcinoma cells: cytogenetic analysis of the stem cell subpopulation.
abstract: The MCF-7 breast carcinoma cell line can be separated by Percoll density gradient centrifugation into several subpopulations, A to F, one of which (E) has been previously suggested to be highly enriched in stem cells. The anchorage-independent growth of the different fractions and its sensitivity to estradiol (E2) and tamoxifen (TAM) was assayed. The anchorage-independent growth capacity of the different fractions was E greater than A greater than B greater than D greater than C,F. The E fraction had the highest clonogenic index (6.62 +/- 1.18) and was unaffected by E2 or TAM. The karyotypic analysis of the E fraction revealed features similar to those of the unfractionated cell line. It is suggested that the high growth rate of fraction E is due to an enrichment in stem cells and not to the existence of a different clone.
authors.affiliation: Hospital Mariano R. Castex, San Martín, Provincia de Buenos Aires, Argentina.
authors.forename: O L
authors.initials: OL
authors.lastname: Podhajcer
authors.forename: M
authors.initials: M
authors.lastname: Resnicoff
authors.forename: L
authors.initials: L
authors.lastname: Bover
authors.forename: E E
authors.initials: EE
authors.lastname: Medrano
authors.forename: I
authors.initials: I
authors.lastname: Slavutsky
authors.forename: I
authors.initials: I
authors.lastname: Larripa
authors.forename: J
authors.initials: J
authors.lastname: Mordoh
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology*; D002448:Cell Adhesion / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D004958:Estradiol / Q000494:pharmacology*; D005819:Genetic Markers; D006801:Humans; D007621:Karyotyping; D014411:Neoplastic Stem Cells / Q000166:cytology / Q000187:drug effects*; D013629:Tamoxifen / Q000494:pharmacology*
chemical_list: D005819:Genetic Markers; D013629:Tamoxifen; D004958:Estradiol