title: Inhibitory effects of Chinese nutritional herbs in isogenic breast carcinoma cells with modulated estrogen receptor function.
abstract: In estrogen receptor (ER)+ MCF-7 cells, ER represents a ligand-activated transcription factor, and 17β-estradiol (E2) represents its physiological ligand. Maintenance of the human breast carcinoma-derived MCF-7 cells with 0.7% serum selected a proliferative sub-population of E2-responsive cells with transiently non-functional ER due to limited availability of E2. Culture of MCF-7 cells in the presence of either 0.7% serum, <1 nM E2 or 0.7% serum + 20 nM E2 selected isogenic cells with either non-functional ER (ER-NF) or functional ER (ER-F) phenotype. The two phenotypes responded to the growth-promoting effects of E2 and to the growth-inhibitory effects of the selective ER modulator tamoxifen, indicating retention of E2 responsiveness. Comparative dose-response experiments with Chinese nutritional herbs on ER-NF and ER-F cells identified the inhibitory concentration (IC)50 values for these herbs, while the IC50 ratios for the ER-NF:ER-F phenotypes facilitated their rank ordering in terms of efficacy. Out of the 11 efficacious herbs tested, five herbs exhibited ER-F > ER-NF inhibitory activity, four exhibited ER-F = ER-NF inhibitory activity and two exhibited ER-NF > ER-F inhibitory activity. Extracts from representative herbs,Lycium barbarum bark,Epimedium grandiflorumandCornus officinalis, from each of the three groups inhibited anchorage-independent growth, induced G1or G2/M arrest and/or apoptosis, and generated anti-proliferative E2metabolites. The differential growth inhibition in ER-NF and ER-F phenotypes, together with the mechanistic efficacy of representative herbs, identified potential leads for their efficacy on ER+and/or ER- breast cancer.
authors.affiliation: Cancer Prevention Research Program, Palindrome Liaisons Consultants, Montvale, NJ 07645-1559, USA.
authors.forename: Nitin
authors.initials: N
authors.lastname: Telang
authors.affiliation: American Foundation for Chinese Medicine, New York, NY 1103-0905, USA.
authors.forename: Guo
authors.initials: G
authors.lastname: Li
authors.affiliation: Hampton University Skin of Color Research Institute, Hampton, VA 23668, USA; Department of Dermatology and Leroy T. Canoles Jr Cancer Research Center, Eastern Virginia Medical School, Norfolk, VA 23507, USA.
authors.forename: Meena
authors.initials: M
authors.lastname: Katdare
authors.affiliation: Hackensack University Medical Center, Hackensack, NJ 07601, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Sepkovic
authors.affiliation: Hackensack University Medical Center, Hackensack, NJ 07601, USA.
authors.forename: Leon
authors.initials: L
authors.lastname: Bradlow
authors.affiliation: American Foundation for Chinese Medicine, New York, NY 1103-0905, USA; Department of Integrative Medicine, Mount Sinai Beth Israel Medical Center, New York, NY 10003, USA.
authors.forename: George
authors.initials: G
authors.lastname: Wong
keywords: growth inhibition; isogenic breast carcinoma cells; nutritional herbs