Some Important Prostate Supplementation Clinical Trials: A Short Summary and Compilation
James Meschino DC, MS, ROHP
Soy Extract Supplementation
Soy Study 1. In a an intervention study, involving men with existing prostate cancer, supplementation with 100 mg per day of soy isoflavones showed a favorable outcome in stabilizing PSA levels
- In this study soy isoflavone supplementation was shown to decrease the rate of rise in serum PSA levels in patients with androgen-dependent and androgen-independent prostate cancer. These researchers concluded that their data suggests that soy isoflavones may benefit some patients with prostate cancer by slowing the progression of the disease and therefore, potentially delaying the development of symptoms, improving quality of life, and perhaps even prolonging survival.
Refernce: Hussain M, Banerjee M, Sarkar FH et al. Soy isoflavones in the treatment of prostate cancer. 2003. Nutr and Cancer, 42;2: 111-117
Study 2. In a Phase II clinical trial (2007) researchers investigated the efficacy of lycopene alone or in combination with soy isoflavones on serum PSA levels in men with prostate cancer. To be eligible for the study, men with prostate cancer had to have rising serum PSA following local therapy or while on hormone therapy. The study population included 71 patients who had 3 successive rising PSA levels or a minimum PSA of 10 ng/ml at 2 successive evaluations prior to starting therapy.
- Subjects were randomly assigned to receive a tomato extract capsule containing 15 mg of lycopene alone (n = 38) or together with a capsule containing 40 mg of a soy isoflavone mixture (n = 33) twice daily orally for a maximum of 6 mo. One patient on the lycopene arm did not receive therapy due to his inability to ingest the study pill.
- Results: There was no decline in serum PSA in either group. However, 35 of 37 (95%) patients in the lycopene group and 22 of 33 (67%) patients in the lycopene plus soy isoflavone group achieved stable disease, meaning that they achieved stabilization in serum PSA level.
- The data suggest that lycopene and soy isoflavones have important adjunctive effects in prostate cancer patients with PSA relapse disease and may delay progression of both hormone-refractory and hormone-sensitive prostate cancer.
Reference: Vaishampayan U, Hussain M, Seren S, Sarkar F, Fontana J et al.Lycopene and Soy Isoflavones in the Treatment of Prostate Cancer. Nutri and Cancer. 2007; 59 (1): 1-7
Study 3. Dr Dean Ornishpublished a study (2005) testing effectiveness of an intensive dietary and lifestyle program as the sole treatment of prostate cancer in men with low to moderate Gleason Scores. The program consisted of a low animal fat diet (with the exception of some fish), and emphasis on fruits, vegetables, legumes, soy products and other vegetarian foods (and dairy-free).
He also supplemented these men with antioxidants (vitamin C, selenium and vitamin E), and included moderate aerobic exercise, and stress management interventions in the treatment group.
The daily antioxidant supplement dosages were:
- Vitamin C – 2000 mg
- Vitamin E – 400 IU
- Selenium – 200 mcg
- Ornish studied 93 men who had chosen not to undergo conventional surgical or radiation treatment for prostate cancer. Half of these men were randomly allocated to the Ornish program, while the remainder served as a non-treated comparison group.
- Results: After 12 months, the PSA of the treated group of men decreased an average of 0.25 ng/ml or 4%, and the PSA of the non-treated group of men increased an average of 0.38 ng/ml or 6%.
Reference: Ornish Dean et al: Intensive lifestyle changes may affect the progression of prostate cancer. The Journal of Urology Vol.174:1065, 2005
A 62-year-old man with androgen-independent metastatic prostate cancer that had failed to respond to multiple treatment regimens stopped all conventional therapy and began taking 10 mg/day of lycopene and 300 mg of saw palmetto 3-times per day.
The prostate-specific antigen (PSA) level decreased from 365 ng/ml to 140 ng/ml after 1 month and to dropped to 8.1 ng/ml after 2-months.
A repeat bone scan revealed an improvement of bony metastases. He has continued the lycopene and saw palmetto and has remained asymptomatic for an unspecified period of time.
Reference: Matlaga BR, Hall MC, Stindt D, Torti FM. Response of hormone refractory prostate cancer to lycopene. J Urol 2001;166:613.
Source: Clinical Cancer Research, 2009 “Dietary Omega-3 Fatty Acids, Cyclooxygenase-2 Genetic Variation, and Aggressive Prostate Cancer Risk”
Authors: V. Fradet, I. Cheng, G. Casey, J.S. Witte
- Researchers performed a case-control analysis of 466 men diagnosed with aggressive prostate cancer and 478 healthy men. Diet was assessed by a food frequency questionnaire and researchers genotyped nine COX-2 single nucleotide polymorphisms.
- Researchers divided omega-3 fatty acid intake into four groups based on quartiles of intake. Men who consumed the highest amount of long chain omega-3 fatty acids had a 63 percent reduced risk of aggressive prostate cancer compared to men with the lowest amount of long chain omega-3 fatty acids.
- The researchers then assessed the effect of omega-3 fatty acid among men with the variant rs4647310 in COX-2, a known inflammatory gene.
- Men with low long chain omega-3 fatty acid intake and this variant had a more than five-fold increased risk of advanced prostate cancer.
- But men with high intake of omega-3 fatty acids had a substantially reduced risk, even if they carried the COX-2 variant.
- “The COX-2 increased risk of disease was essentially reversed by increasing omega-3 fatty acid intake by a half a gram (500 mg) per day,” said Witte. “If you want to think of the overall inverse association in terms of fish, where omega-3 fatty acids are commonly derived, the strongest effect was seen from eating dark fish such as salmon one or more times per week.”
Lycopene Clinical Trials
Study 1. In one study, the effect of tomato sauce on apoptosis in benign prostate hyperplasia (BPH) tissue and carcinomas was examined. 26 patients who were scheduled for prostatectomy were given tomato sauce pasta entrees (30 mg/day of lycopene) to eat daily for 3 weeks before surgery.
- Patients scheduled for surgery who did not receive the tomato sauce pasta entrees served as control subjects.
Results: Those who consumed the tomato sauce pasta entrees exhibited decreased serum PSA levels and increased apoptotic cell death in BPH tissue and carcinomas
Reference: Kim HS, Bowen P, Chen L, et al.: Effects of tomato sauce consumption on apoptotic cell death in prostate benign hyperplasia and carcinoma. Nutr Cancer 47 (1): 40-7, 2003.
Study 2. In a 2004 open-label study, patients with hormone-refractory prostate cancer (HRPC) received lycopene supplements daily (10 mg/day of lycopene) for 3 months.
- Of the study’s participants, 50% had PSA levels that remained stable, 15% showed biochemical progression, 30% showed a partial response, and one patient (5% of the total sample) exhibited a complete response after treatment.
Reference: Ansari MS, Gupta NP: Lycopene: a novel drug therapy in hormone refractory metastatic prostate cancer. UrolOncol 22 (5): 415-20, 2004 Sep-Oct
Study 3. Prostate Cancer Patients received lycopene supplements (30mg/day) or no intervention twice daily for 3 weeks prior to radical prostatectomy.
- Patients who received the lycopene supplements had smaller tumors and lower serum PSA levels than patients who did not receive the supplements.
- These results suggest that lycopene may be beneficial in prostate cancer treatment
Reference: Kucuk O, Sarkar FH, Djuric Z, et al.: Effects of lycopene supplementation in patients with localized prostate cancer. ExpBiol Med (Maywood) 227 (10): 881-5, 2002.
Study 4. A 2006 study investigated whether lycopene supplements (10 mg/day) would affect PSA velocity in patients with localized prostate cancer.
- There was a statistically significant decrease in PSA velocity following lycopene treatment as well as a large, but not statistically significant, increase in PSA doubling time
Reference: Barber NJ, Zhang X, Zhu G, et al.: Lycopene inhibits DNA synthesis in primary prostate epithelial cells in vitro and its administration is associated with a reduced prostate-specific antigen velocity in a phase II clinical study. Prostate Cancer Prostatic Dis 9 (4): 407-13, 2006.
Study 5. Patients with high-grade prostate intraepithelial neoplasia (HGPIN) received 4 mg of lycopene twice a day or no lycopene supplementation for 2 years.
Results: A greater decrease in serum PSA levels was observed in those treated with lycopene supplements compared with those who did not take the supplementation.
- During follow-up, adenocarcinomas occurred more often in patients who had not received the supplements than in patients who had received lycopene.
- These findings suggest that lycopene may be effective in preventing HGPIN from progressing to prostate cancer
Reference: Bunker CH, McDonald AC, Evans RW, et al.: A randomized trial of lycopene supplementation in Tobago men with high prostate cancer risk. Nutr Cancer 57 (2): 130-7, 2007
- Two clinical studies shown that men with established prostate cancer realized a marked slowing of their disease when they drank 8 ounces of pure pomegranate juice each day.
- Reporting at the 104th Annual Meeting Scientific Meeting of The American Urology Association, researchers presented findings showing that men, who had undergone prostate surgery or radiation treatment for localized prostate cancer, benefited from drinking 8 ounces per day of pomegranate juice if their PSA levels were still continuing to rise.
- In men giving the pomegranate juice the doubling time of their PSA was extended to 60 months, compared to only 15.4 months prior to pomegranate juice administration.
- Previously, a study in the Journal of Clinical Cancer Research in 2006 showed that men, with established prostate cancer, extended the PSA doubling time from 15 months to 54 months when they began drinking 8 ounces of pomegranate juice each day
How Does Pomegranate Juice Work?
No one knows for sure but the juice is very rich in a class of unique polyphenol antioxidants known as ellagitannin compounds.
It’s possible that these, or other compounds, slow the rate at which prostate cancer cells replicate and/or trigger mechanisms that encourage programmed cell death of existing prostate cancer cells.
Phase II and III trials are planned to better understand the extent to which pomegranate juice can protect the prostate gland and be used in adjunctive management of established prostate cancer cases.
Note: Pomegranate Juice contains carbohydrate calories, and thus, is precluded from the ketogenic diet plan.
However, it can be used to help prevent prostate cancer and as follow-up intervention in prostate cancer survivors (post-treatment)