Laboratory�/�Preclinical Studies
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A 1998 study that evaluated estrogenic activity of extracts of PC-SPES, ginseng (Panax ginseng C.A. Meyer), saw palmetto, DES, and estrone (estradiol-17 beta) in vitro reported on the estrogenic response of ovariectomized CD-1 mice to PC-SPES extract as well as the response to PC-SPES capsules in eight prostate cancer patients who had received previous therapy.[5] This study used four samples of PC-SPES ordered in separate purchases from BotanicLab. No lot numbers were supplied in the study. Lot numbers from October 1996 through July 1998 were later tested for contamination and had DES levels of 114.74 ?g/g to 159.27 ?g/g, as well as the highest detected levels of indomethacin of the PC-SPES lots tested.[6]In vitro tests of PC-SPES extract or estradiol showed estrogenic activity similar to 1 nM estradiol on estrogen receptor Y253 yeast strain. Transcriptional activation assays in yeast strain PL3 Saccharomyces cerevisiae with ethanolic extract of PC-SPES exhibited estrogen-like effects. In the eight prostate cancer patients, serumtestosterone concentrations decreased during the use of PC-SPES and increased within 3 weeks after treatment was discontinued. PSA levels decreased in all eight patients. Side effects in all eight patients were similar to those seen after treatment with estrogen: breast tenderness and loss of libido. One patient had superficial venous thrombosis. In addition to baicalin, two other compounds purified from PC-SPES, isoliquiritigenin and wogonin, have been shown to reduce PSA levels and downregulate AR.[7]
References:
- Hsieh TC, Lu X, Chea J, et al.: Prevention and management of prostate cancer using PC-SPES: a scientific perspective. J Nutr 132 (11 Suppl): 3513S-3517S, 2002.
- Kubota T, Hisatake J, Hisatake Y, et al.: PC-SPES: a unique inhibitor of proliferation of prostate cancer cells in vitro and in vivo . Prostate 42 (3): 163-71, 2000.
- Ko R, Wilson RD, Loscutoff S: PC-SPES. Urology 61 (6): 1292, 2003.
- Hsieh TC, Wu JM: Mechanism of action of herbal supplement PC-SPES: elucidation of effects of individual herbs of PC-SPES on proliferation and prostate specific gene expression in androgen-dependent LNCaP cells. Int J Oncol 20 (3): 583-8, 2002.
- DiPaola RS, Zhang H, Lambert GH, et al.: Clinical and biologic activity of an estrogenic herbal combination (PC-SPES) in prostate cancer. N Engl J Med 339 (12): 785-91, 1998.
- Sovak M, Seligson AL, Konas M, et al.: Herbal composition PC-SPES for management of prostate cancer: identification of active principles. J Natl Cancer Inst 94 (17): 1275-81, 2002.
- Chen S, Gao J, Halicka HD, et al.: Down-regulation of androgen-receptor and PSA by phytochemicals. Int J Oncol 32 (2): 405-11, 2008.
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