Effects of CLA on ERα(+) human breast cells. (A) MTS assay, (B) Apo-ONE® homogeneous caspase-3/7 assay and (C) Hoechst staining for 3 days of treatment with CLA, Tam and E2 alone or combined with each other in MCF-7 cells. CLA stands for 40 μM t10, c12-CLA; Tam stands for 1 μM 4-Hydroxytamoxifen; E2 stands for 10 nM 17β-estradiol. CLA exerts combinative effects with tamoxifen in MCF-7 cells. (D) Western blot analysis of basal ERα protein expression in MCF-7 and primary cultured ERα positive normal human breast epithelial cells (ERα(+) NEC). Equal amounts of isolated protein from both cell extracts were subjected to immunoblot with anti-ERα antibodies. β-actin was used as loading control. Histogram: Apo-ONE® homogeneous caspase-3/7 assay for the effects of treatment on apoptosis in MCF-7 and ERα(+) NEC for 3 days of treatment. (E) and (F) showed the effects of CLA and E2 on proliferation (MTS assay) and apoptosis (Hoechst staining) in ERα(+) NEC, respectively. 80 μM t10, c12-CLA; E2 stands for 10 nM 17β-estradiol. Bars represent mean ± SD, n = 3. *p < 0.05.