Effect of daidzein and equol on DNA replication in MCF-7 cells. (15th January 2018)

• Record Type: Journal Article
• Authors: Tsuji, Mako; Tanaka, Tomoki; Nagashima, Ryosuke; Sagisaka, Yuka; Tousen, Yuko; Nishide, Yoriko; Ishimi, Yoshiko; Ishimi, Yukio
• Is Part Of: Journal of biochemistry. Volume 163:Number 5(2018:May)
• Page Start: 371
• Page End: 380
• Publication Date: 2018-01-15
• Subjects: cell cycle -- steroid hormones -- DNA replication -- gene expression; Biochemistry -- Periodicals; Biochemistry -- Periodicals; Electronic journals; 572.05
• DOI: 10.1093/jb/mvy006
• Languages: English
• ISSNs: 0021-924X

Abstract

Abstract: It has been reported that daidzein and equol stimulate DNA replication and proliferation of MCF-7 cells. However, their molecular mechanisms of action are still unclear. We examined the effects of daidzein and equol on DNA replication of MCF-7 cells, focusing on MCM2-7 proteins, which function as the replicative helicase. In the presence of either 1 μM of daidzein or equol, the number of cells in S-phase, which was determined by detecting bromodeoxyuridine incorporated into replicated DNA, almost doubled. The total amounts of MCM7 protein and chromatin-bound MCM7 protein increased in the presence of daidzein. The data suggest that phytoestrogens facilitate cell cycle progression in G1-phase by increasing the level of MCM proteins. In the presence of phytoestrogens, phosphorylation of Rb and levels of MCM2, 3 and 7 mRNA increased, suggesting that stimulation of MCM2-7 transcription is involved in the cell cycle progression. Under the same conditions, double-stranded DNA breakage in logarithmically growing MCF-7 cells, which was detected using anti-γ-H2AX antibodies, did not increase in the presence of equol.