PMC

γ-TmT induces Nrf2-mediated antioxidant response and reduces serum 8-isoprostane in E2-treated ACI rats. (A) qPCR analysis of mRNA expression of Nrf2 and its downstream targets, NQO1, GCLM and HMOX1, in rat mammary glands (6 and 18 weeks) and mammary tumors (31 weeks) (n=6–8/group). (B) Western blot analysis of Nrf2, NQO1, GCLM and HMOX1 in the mammary tumors of ACI rats at 31 weeks (n=3/group). (C) Analysis of the 8-isoprostane levels in the serum of ACI rats at 6, 18 and 31 weeks (n=6/group). Statistical significance, *P < 0.05, ***P < 0.001.

γ-TmT reduces serum E2 levels and induces estrogen metabolizing enzyme CYP1A1 in E2-treated ACI rats. (A) Analysis of E2 levels in ACI rat serum at 6, 18 and 31 weeks (n=6/group for 6, 18 weeks; n=9/group for 31 weeks). (B) qPCR analysis of CYP1A1 and CYP1B1 mRNA expression in the mammary glands (6, 18 weeks), tumors (31 weeks) and liver (31 weeks) of ACI rats (n=6–8/group). Statistical significance, *P < 0.05, **P < 0.01, ***P < 0.001. (C) Western blot analysis of CYP1A1 and CYP1B1 in the mammary tumors of ACI rats at 31 weeks (n=3/group).

γ-TmT regulates nuclear receptor signaling and cell proliferation in E2-treated ACI rats. (A) qPCR analysis of mRNA expression of ERβ, PPARγ, PTEN, and p27 in the mammary glands (6 and 18 weeks) and mammary tumors (31 weeks) of ACI rats (n=6–8/group). (B) Representative images of PCNA staining in the mammary tumors of ACI rats (40X magnification). The scale bar represents 50 μm. Quantification of nuclear PCNA staining in the mammary tumors (n=3/group) is shown. Statistical significance, *P < 0.05, **P < 0.01.

γ-TmT inhibits estrogen-induced mammary tumorigenesis in ACI rats. ACI rats implanted with E2 were fed with control diet or diet containing different doses of γ-TmT for 31 weeks (n=30/group). (A) The tumor-free survival curve of each group is shown. (B) Average tumor volume of the different treatment groups at 31 weeks is shown. (C) Average tumor multiplicity of each group at 31 weeks is shown. (D) Average body weights of each treatment group at 31 weeks are shown. P-values are compared to E2 control. Statistical significance, *P < 0.05, **P < 0.01.

γ-TmT inhibits E2-induced mammary tumor growth in MCF-7 xenografted mice. Nu/nu mice were implanted with E2 pellets (0.72 mg). After 2 days, MCF-7 cells were injected into the mammary fat pad of the mice. From the day of MCF-7 cell injection, mice were fed with control diet or different doses of γ-TmT diet for 9 weeks (n=10/group). (A) Average tumor volume at weekly time points for the different treatment groups is shown. (B) Average tumor weight at 9 weeks is shown. Statistical significance, *P < 0.05, **P < 0.01.