title: Ganoderma lucidum inhibits proliferation of human breast cancer cells by down-regulation of estrogen receptor and NF-kappaB signaling.
abstract: Ganoderma lucidum, an oriental medical mushroom, has been used in Asia for the prevention and treatment of a variety of diseases, including cancer. We have previously demonstrated that G. lucidum inhibits growth and induces cell cycle arrest at G0/G1 phase through the inhibition of Akt/NF-kappaB signaling in estrogen-independent human breast cancer cells. However, the molecular mechanism(s) responsible for the inhibitory effects of G. lucidum on the proliferation of estrogen-dependent (MCF-7) and estrogen-independent (MDA-MB-231) breast cancer cells remain to be elucidated. Here, we show that G. lucidum inhibited the proliferation of breast cancer MCF-7 and MDA-MB-231 cells by the modulation of the estrogen receptor (ER) and NF-kappaB signaling. Thus, G. lucidum down-regulated the expression of ERalpha in MCF-7 cells but did not effect the expression of ERbeta in MCF-7 and MDA-MB-231 cells. In addition, G. lucidum inhibited estrogen-dependent as well as constitutive transactivation activity of ER through estrogen response element (ERE) in a reporter gene assay. G. lucidum decreased TNF-alpha-induced (MCF-7) as well as constitutive (MDA-MB-231) activity of NF-kappaB. The inhibition of ER and NF-kappaB pathways resulted in the down-regulation of expression of c-myc, finally suppressing proliferation of estrogen-dependent as well as estrogen-independent cancer cells. Collectively, these results suggest that G. lucidum inhibits proliferation of human breast cancer cells and contain biologically active compounds with specificity against estrogen receptor and NF-kappaB signaling, and implicate G. lucidum as a suitable herb for chemoprevention and chemotherapy of breast cancer.
authors.affiliation: Cancer Research Laboratory, Methodist Research Institute, Indianapolis, IN 46202, USA.
authors.forename: Jiahua
authors.initials: J
authors.lastname: Jiang
authors.forename: Veronika
authors.initials: V
authors.lastname: Slivova
authors.forename: Daniel
authors.initials: D
authors.lastname: Sliva
mesh_terms: D001943:Breast Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D049109:Cell Proliferation / Q000187:drug effects*; D015536:Down-Regulation; D047628:Estrogen Receptor alpha / Q000037:antagonists & inhibitors / Q000378:metabolism*; D047629:Estrogen Receptor beta / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006801:Humans; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010936:Plant Extracts / Q000494:pharmacology*; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D020940:Reishi / Q000737:chemistry*; D015398:Signal Transduction / Q000187:drug effects*; D015533:Transcriptional Activation; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D016328:NF-kappa B; D010936:Plant Extracts; D016271:Proto-Oncogene Proteins c-myc; D014409:Tumor Necrosis Factor-alpha