Recent progress on nutraceutical research in prostate cancer

Abstract

Recently, nutraceuticals have received increasing attention as the agents for cancer prevention and supplement with conventional therapy. Prostate Cancer (PCa) is most frequently diagnosed cancer and second leading cause of cancer-related death in men in US. Growing evidences from epidemiological studies, in vitro experimental studies, animal studies, and clinical trials have shown that nutraceuticals could be very useful for the prevention and treatment of PCa. Several nutraceuticals including isoflavone, indole-3-carbinol, 3,3’-diindolylmethane, lycopene, (-)-epigallocatechin-3-gallate, and curcumin are known to down-regulate the signal transductions in AR, Akt, NF-κB, and other signal transduction pathways which are vital for the development of PCa and the progression of PCa from androgen-sensitive to castrate-resistant PCa. Therefore, nutraceutical treatment in combination with conventional therapeutics could achieve better treatment outcome in prostate cancer therapy. Interestingly, some nutraceuticals could regulate the function of cancer stem cell (CSC) related miRNAs and associated molecules, leading to the inhibition of prostatic CSCs which are responsible for drug-resistance, tumor progression, and recurrence of PCa. Hence, nutraceuticals may serve as powerful agents for the prevention of PCa progression and they could also be useful in combination with chemotherapeutics or radiotherapy. Such strategy could become a promising newer approach for the treatment of metastatic PCa with better treatment outcome by improving overall survival.

c-Myc is a novel target of cell cycle arrest by honokiol in prostate cancer cells

“…Plants used in alternative and complimentary medicine are attractive for identification of small molecules potentially useful for prevention and/or treatment of prostate cancer. 5 Magnolia tree is one such example whose bark extract is widely used in the traditional medicine practices in China, Korea, and Japan. 6 The bioactive lignans in the bark, seed cones, and leaves of Magnolia tree include honokiol (HNK), magnolol, and obovatol but former is the best characterized for its anticancer activity.…”

Green Tea and Its Extracts in Cancer Prevention and Treatment

“…An increased risk for prostatic cancer correlates with reduced physical activity [183], high BMI [184,185] and diabetes mellitus [186]; farming has been published as a risk factor (although pesticide use is reported as protective; [187]), and lycopene from tomatoes [181,188], catechins, isoflavons and curcumin [7] are probably protective.…”

“…A popular book by Miller [5] is entitled "We can win the war against cancer by aggressively pursuing prevention". Consequently, herbal extracts are marketed as teas (http://www.canceractive.com) or tea extracts [6,7] as "health food" or dietary supplements for the prevention and treatment of cancer. Claims extend to green tea (GT) [4,7,8], black tea (BT) [9] and extracts from green tea (GTE) [10].…”

“…Consequently, herbal extracts are marketed as teas (http://www.canceractive.com) or tea extracts [6,7] as "health food" or dietary supplements for the prevention and treatment of cancer. Claims extend to green tea (GT) [4,7,8], black tea (BT) [9] and extracts from green tea (GTE) [10]. Whereas green and black tea contain all water soluble components of tea leaves in differing amounts, green tea extract mostly contains catechins and gallocatechins, with low amounts of methylxanthines [11][12][13].…”

Phytotherapeutic interventions in the management of biochemically recurrent prostate cancer: a systematic review of randomised trials

“…These include inhibition of proliferation, induction of apoptosis, and cell cycle arrest. Soy isoflavones, indole-3-carbinol and 3,3 0 -diindolylmethane from broccoli, lycopene (predominantly found in tomatoes), (À)-epigallocatechin-3-gallate (green tea polyphenols), and curcumin from turmeric, are known to downregulate the signal transductions in androgen receptor (AR), protein kinase B (Akt), nuclear factor-jB (NF-jB), and other signal transduction pathways [18]. In vitro, sulphoraphane can inhibit cancer cells through a variety of mechanisms including inflammation, angiogenesis, and metastasis, and in vivo, its administration inhibited prostate cancer progression and metastasis in transgenic adenocarcinoma of the mouse prostate (TRAMP) mice [11].…”