Does PSA Promote Prostate Cancer?
By William Faloon
|LE Magazine Special Edition, Winter 2005/2006|
Does PSA Promote Prostate Cancer?by William Faloon
Reviewed and critiqued by Stephen B. Strum, MD, FACP
Lycopene Reduces Prostate Cell DNA Damage
Because cancer is initiated and promoted as the result of ongoing DNA damage, researchers conducted a study to evaluate the genomic effects of lycopene in men with localized disease. For three weeks, a group of 32 men consumed tomato sauce each day supplying 30 mg of lycopene. Prostate tissue was obtained initially at biopsy and then again after surgical removal of the prostate gland.38 After three weeks, PSA levels declined by 17.5% and a blood marker of DNA damage fell by 21.3%. An analysis of the prostate tissues showed that the lycopene-supplemented patients had major reductions in many of the DNA factors that usually favor uncontrolled prostate cancer cell propagation. Moreover, in the lycopene-supplemented patients, prostate cancer cells as well as hyperplastic prostatic tissue showed an increase in apoptosis (programmed cell death). This study showed that prostate cells readily take up lycopene, with cellular lycopene levels increasing 2.92-fold after only three weeks. This increase in lycopene correlated with a significant reduction of DNA damage in prostate tissue.38
Boron Shrinks Prostate Tumors, Reduces PSA in Mice
As noted earlier, most doctors regard PSA solely as a useful laboratory marker for diagnosing prostate cancer. At a cellular level, however, PSA functions as an active growth factor in the prostate gland. One such mechanism involves PSA’s enzymatic ability to degrade extracellular matrix (structural support) proteins such as fibronectin and laminin.1 This action of PSA may promote tumor growth and metastasis. Another potential tumor-promoting action of PSA involves freeing insulin-like growth factor 1 (IGF-1) from its binding protein (BP-3), providing increased local levels of IGF-1, leading to tumor growth.2,3 To understand the nature of our enemy—the cancer cell—we must realize that the tumor cell is functional and produces cell products that favor its growth, invasiveness, and spread!
Studies by Gallardo-Williams and colleagues have shown that boric acid and boronic acid significantly inhibit the degradation of fibronectin by enzymatically active PSA.1 In another study in mice the same authors used immunohistochemistry staining of tissues to show that expression of IGF-1 in tumors was markedly reduced by boric acid. In response to both low- and high-dose boron supplementation, PSA levels plummeted by an average of 87%, while tumor size declined by 31.5% on average. Also noted was a significantly lower incidence of mitotic figures in the boron-supplemented groups. Mitotic figures reflect DNA synthesis and proliferative activity.39
Consistent with these findings, a recent study showed that boron inhibited the proliferation of prostate cancer cell lines DU-145 (an androgen-independent line) and LNCaP (an androgen-dependent cell line) in a dose-dependent manner.40 These animal and cell line studies appear to be relevant to humans, based on a report from UCLA in which Cui and colleagues showed that men with the highest dietary boron intake reduced their prostate cancer risk by 54% compared to men with the lowest boron intake!12 While the authors noted that the observed association should be interpreted with caution because of the small case sample size and the nature of the cross-sectional study design, clearly these findings deserve further investigation. If the above-cited animal studies can be replicated in human patients, boron at doses ranging from 6 to 15 mg a day may become an effective and very low-cost adjuvant therapy.12
Curcumin Induces Cancer Cell Suicide
Cancer cells do not follow normal, healthy cell suicide programs. Old cells need to die and be discarded, but cancer cells proliferate and grow.
Numerous studies over the past two years have identified specific mechanisms by which curcumin inhibits the growth of prostate cancer cells and then activates genes that tell cancer cells to self-destruct (also referred to as apoptosis).41,42 One study showed that curcumin reprograms prostate cancer cells so as to make them less likely to metastasize to the bone, while another study demonstrated that curcumin has radiation-sensitizing effects, making cancer cells more vulnerable to destruction by conventional radiation therapy.43,44 The research on curcumin is so promising that pharmaceutical companies are currently developing curcumin analogs that can be patented as anti-cancer therapies.45,46
Critical Importance of Annual PSA Testing
In 2004, the New England Journal of Medicine published an article indicating that the rate of increase in PSA is a more important predictor of mortality than the PSA reading itself. Men who showed a 2.0 ng/ml or greater increase in PSA from the previous year’s level were 10 times more likely to die within seven years.47 The researchers recommended that men over the age of 35 should have a baseline PSA reading and then retest each year to measure the rate of increase (PSA velocity). A sharp rise in PSA mandates the need for more comprehensive evaluation and treatment. Without previous PSA readings, it is impossible for your doctor to calculate PSA velocity. Optimal measurement of PSA velocity requires at least three PSA readings, with each obtained at least six months apart and tested at the same laboratory using the same PSA laboratory procedure.
In summary, accumulating data suggest that PSA is no longer merely a laboratory test of prostate gland activity. Instead, PSA is recognized as a functional protein: an enzyme that may facilitate prostate cancer cell proliferation, invasion, and metastasis. Taking steps to suppress PSA may reduce prostate cancer risk and progression. Meaningful reductions in PSA, as demonstrated in many of the studies cited in this article, appear achievable by using natural supplements like lycopene, soy, green tea, and boron, as well as through prescription drugs such as Avodart® or Proscar®, which normally reduce serum PSA levels by 40-50%.48-50
Low-Cost Blood Testing
A number of blood tests can identify correctable risk factors before clinically advanced disease becomes established. Most people test their blood to ascertain levels of cardiovascular disease markers such as homocysteine, C-reactive protein, LDL (low-density lipoprotein), and HDL (high-density lipoprotein).
While the PSA test has become well known, some men have been reluctant to have it done for fear that it will reveal a problem that cannot be easily corrected. Over the past few years, however, a significant number of publications have revealed safe methods of lowering PSA and potentially reducing prostate cancer risk.
Life Extension members can obtain comprehensive blood test panels at discounted prices. The popular Male Panel includes the PSA test, along with homocysteine, DHEA , C-reactive protein, and numerous other tests. It does not, however, include the dihydrotestosterone (DHT) test that would be of significant importance if PSA levels were in any way elevated.
High DHT levels stimulate the androgen receptor to induce greater PSA production.51 DHT also interacts with extracellular tissues to increase prostate cancer cell mobility.52 These and other findings may well be the basis for the reduction in prostate cancer development seen in men treated with inhibitors of DHT. The normal retail price for the DHT test is $60, but members pay only $45.00 for this test.
More than ever before, determining your PSA (and DHT) levels may dramatically reduce your odds of becoming a prostate cancer victim.
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