Effects of tamoxifen on human breast cancer cell cycle kinetics: Accumulation of cells in early g1 phase

C. Kent Osborne, David H. Boldt, Gary M. Clark

Research output: Contribution to journalArticle

234 Scopus citations

Abstract

We have studied the effects of tamoxifen on the cell cycle kinetics of the endocrine-responsive MCF-7 human breast cancer cells. Tamoxifen inhibits proliferation of MCF-7 cells. The tritiated thymidine labeling index is markedly reduced by tamoxifen, indicating a reduction in the fraction of cells in S phase. Flow cytometry of mithramycin-stained cells reveals that cells accumulate in G1 phase, with a concomitant depletion of S-and G2-M-phase cells with tamoxifen. Mapping of G1-phase cells by morphology of prematurely condensed chromosomes demonstrated that tamoxifen-treated cells accumulate in early G1. These studies indicate that tamoxifen inhibits proliferation of MCF-7 human breast cancer cells by invoking a transition delay early in the G1 phase of the cell cycle.

Original languageEnglish (US)
Pages (from-to)3583-3585
Number of pages3
JournalCancer Research
Volume43
Issue number8
StatePublished - Aug 1 1983

ASJC Scopus subject areas

  • Oncology
  • Cancer Research

Fingerprint Dive into the research topics of 'Effects of tamoxifen on human breast cancer cell cycle kinetics: Accumulation of cells in early g1 phase'. Together they form a unique fingerprint.

  • Cite this