title: Clinical and biologic activity of an estrogenic herbal combination (PC-SPES) in prostate cancer.
abstract: BACKGROUND
  Herbal mixtures are popular alternatives to demonstrated therapies. PC-SPES, a commercially available combination of eight herbs, is used as a nonestrogenic treatment for cancer of the prostate. Since other herbal medicines have estrogenic effects in vitro, we tested the estrogenic activity of PC-SPES in yeast and mice and in men with prostate cancer.
  
  
  METHODS
  We measured the estrogenic activity of PC-SPES with transcriptional-activation assays in yeast and a biologic assay in mice. We assessed the clinical activity of PC-SPES in eight patients with hormone-sensitive prostate cancer by measuring serum prostate-specific antigen and testosterone concentrations during and after treatment.
  
  
  RESULTS
  In complementary yeast assays, a 1:200 dilution of an ethanol extract of PC-SPES had estrogenic activity similar to that of 1 nM estradiol, and in ovariectomized CD-1 mice, the herbal mixture increased uterine weights substantially. In six of six men with prostate cancer, PC-SPES decreased serum testosterone concentrations (P<0.05), and in eight of eight patients it decreased serum concentrations of prostate-specific antigen. All eight patients had breast tenderness and loss of libido, and one had venous thrombosis. High-performance liquid chromatography, gas chromatography, and mass spectrometry showed that PC-SPES contains estrogenic organic compounds that are distinct from diethylstilbestrol, estrone, and estradiol.
  
  
  CONCLUSIONS
  PC-SPES has potent estrogenic activity. The use of this unregulated mixture of herbs may confound the results of standard or experimental therapies and may produce clinically significant adverse effects.
authors.affiliation: Department of Medicine, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, New Brunswick 08901, USA.
authors.forename: R S
authors.initials: RS
authors.lastname: DiPaola
authors.forename: H
authors.initials: H
authors.lastname: Zhang
authors.forename: G H
authors.initials: GH
authors.lastname: Lambert
authors.forename: R
authors.initials: R
authors.lastname: Meeker
authors.forename: E
authors.initials: E
authors.lastname: Licitra
authors.forename: M M
authors.initials: MM
authors.lastname: Rafi
authors.forename: B T
authors.initials: BT
authors.lastname: Zhu
authors.forename: H
authors.initials: H
authors.lastname: Spaulding
authors.forename: S
authors.initials: S
authors.lastname: Goodin
authors.forename: M B
authors.initials: MB
authors.lastname: Toledano
authors.forename: W N
authors.initials: WN
authors.lastname: Hait
authors.forename: M A
authors.initials: MA
authors.lastname: Gallo
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000009:adverse effects / Q000737:chemistry / Q000494:pharmacology*; D001940:Breast / Q000187:drug effects; D004365:Drugs, Chinese Herbal / Q000009:adverse effects / Q000737:chemistry / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007989:Libido / Q000187:drug effects; D008297:Male; D051379:Mice; D010936:Plant Extracts / Q000009:adverse effects / Q000737:chemistry / Q000494:pharmacology*; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000503:physiopathology; D011960:Receptors, Estrogen / Q000187:drug effects*; D012441:Saccharomyces cerevisiae / Q000187:drug effects; D013739:Testosterone / Q000097:blood; D013924:Thrombophlebitis / Q000139:chemically induced; D014599:Uterus / Q000187:drug effects; D015003:Yeasts / Q000187:drug effects
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004365:Drugs, Chinese Herbal; D010936:Plant Extracts; D011960:Receptors, Estrogen; C114209:herbal preparation PC-SPES; D013739:Testosterone; D017430:Prostate-Specific Antigen