New Topic Post Reply Printable Version
[ << Previous Thread | Next Thread >> ]

SHU93
Regular Member


Date Joined Aug 2008
Total Posts : 328
   Posted 6/29/2009 7:34 AM (GMT -7)   
Was released this weekend, interesting mention for those of us already diagnosed and if you take selenium as one your daily supplements. My question is I take the Prostate 2.3 vitamin that contains selenium as one of the ingredients. Do I stop? Also interseting quote at end of article: "There is some precedent to this – research has suggested that antioxidants could be protective if you don't have cancer, but once you do, then antioxidants may be a bad thing."
 
 
Selenium Intake May Worsen Prostate Cancer In Some, Study Reports
 
ScienceDaily (June 27, 2009) — Higher selenium levels in the blood may worsen prostate cancer in some men who already have the disease, according to a study by researchers at Dana-Farber Cancer Institute the University of California, San Francisco.

A higher risk of more-aggressive prostate cancer was seen in men with a certain genetic variant found in about 75 percent of the prostate cancer patients in the study. In those subjects, having a high level of selenium in the blood was associated with a two-fold greater risk of poorer outcomes than men with the lowest amounts of selenium. By contrast, the 25 percent of men with a different variant of the same gene and who had high selenium levels were at 40 percent lower risk of aggressive disease. The variants are slightly different forms of a gene that instructs cells to make manganese superoxide di****ase (SOD2), an enzyme that protects the body against harmful oxygen compounds.

The research findings suggest that "if you already have prostate cancer, it may be a bad thing to take selenium," says Philip Kantoff, MD, director of Dana-Farber's Lank Center for Genitourinary Oncology and senior author of the study that is published by the Journal of Clinical Oncology on its website now and later will be in a print journal. The lead author is June Chan, ScD, of the University of California, San Francisco.

The unexpected results are the first to raise concern about this potentially harmful consequence of taking supplemental selenium. Kantoff says, "These findings are interesting particularly in light of the recent negative results from the SELECT prevention study, which asked if selenium could protect against prostate cancer."

The new study reveals the strong interaction between selenium and SOD2 to influence the biology of prostate cancer, a finding that these investigators had shown in a previous study. The authors say the current research demonstrated that variations in the make up of the SOD2 gene dramatically alter the effects of selenium on the risk of aggressive prostate cancer.

Selenium is a mineral found widely in rocks and dirt. Small amounts of selenium are essential for health: 40 to 70 micrograms is the recommended daily intake. In recent years, supplemental selenium has been sold and promoted as a means of preventing prostate cancer, largely based on observational studies that found higher risk of prostate cancer incidence and mortality in areas of the country that are naturally low in selenium.

However, research aimed at confirming the benefits of selenium supplementation have been mixed. Recently, the SELECT study, which involved 35,000 men, was halted early when, after more than five years, it showed that the supplements didn't affect the incidence of prostate cancer.

Previous studies had found that the risk of developing prostate cancer was modified by a strong interaction between SOD2 and selenium. The new research was designed to look at the effect of this interaction on men already diagnosed with prostate cancer.

Scientists examined banked blood samples, DNA, and medical records of 489 male Dana-Farber patients diagnosed between 1994 and 2001 with localized or locally advanced prostate cancer. Their mean age was 62, and their mean PSA (prostate-specific antigen) measurement was 6.0 ng/mL. about half the men were assessed as having a good disease risk, one-third had an intermediate risk, and the remaining one-sixth were at poor risk. The researchers measured the level of selenium in the blood and, using the stored DNA, they determined the SOD2 genotype -- the specific form of the SOD2 gene carried by each patient.

Simply having a high level of selenium was associated with a slightly elevated risk of aggressive prostate cancer. But the risk was much more strongly affected by the interaction of selenium levels and whether the patient had a certain variant of the SOD2 gene. Men with the highest selenium levels and the "AA" form of the SOD2 gene were 40 percent less likely to have been diagnosed with aggressive prostate cancer than the men with same gene form but low levels of selenium.

But for men carrying the "V" form of the gene, selenium had the opposite effect. In these men, those with the highest levels of selenium in their blood were about twice as likely to have an aggressive type of prostate cancer as their counterparts with low selenium levels, says Kantoff, who is also a professor of medicine at Harvard Medical School.

The study couldn't determine whether any of the men had been taking selenium supplements or not. But the researchers noted that men in the large SELECT prevention trial had a much higher average selenium level than those in the current study.

"Among the 25 percent of men with the AA genotype, having greater selenium levels may protect against aggressive disease," the authors concluded. "However, for the 75 percent of men who carry a V allele, higher selenium levels might increase the likelihood of having worse characteristics."

Therefore, they add, it is important to know which type of SOD2 gene a man has when considering the risks and potential benefits of taking selenium supplements. Additionally, the authors say the effects of the interaction between the SOD2 genotype and selenium may help explain apparently conflicting results of previous studies.

The results may seem counterintuitive to the public, who have been told for years that antioxidants can help people live longer, healthier lives with a lowered risk of cancer. However, Kantoff says, "There is some precedent to this – research has suggested that antioxidants could be protective if you don't have cancer, but once you do, then antioxidants may be a bad thing."

In addition to Kantoff and Chan, other authors of the paper include William Oh, MD, Wanling Xie, PhD, Meredith Regan, ScD, and Miyako Abe, PhD, of Dana-Farber; Meir J. Stampfer DrPH, MD, of Brigham and Women's Hospital and the Harvard School of Public Health, and Irena King, PhD, of the Fred Hutchinson Cancer Research Center, Seattle.

The work was supported by grants from the National Cancer Institute and several foundations and charitable organizations.

 


Age Dx 37, 7/2008
First PSA : 4.17 5/2008
Second PSA After 2 weeks of antibiotics : 3.9 6/2008
DRE: Negative 5/2008
Biopsy : 6 out 12 Postive all on right side, Gleason 7 (3+4).
Bone Scan/CAT Scan: Clear 7/2008
Cystoscope: Normal 7/2008
Prostate MRI: Normal 7/2008
Da Vinci Surgery 7/2008
PostOp: T2c (On Both sides), margins clear, seminal clear, nodes, clear. Gleason 6(3+3).
First PostOp PSA 9/2008: <0.01
2nd PSA 12/2008: <0.1 (Different Lab then 1st)
3rd PSA 3/2009: <0.1
4th PSA 6/2009: <0.1
 
 
 


geezer99
Veteran Member


Date Joined Apr 2009
Total Posts : 990
   Posted 6/29/2009 8:20 AM (GMT -7)   
Great information -- thanks.

The real problem, if selenium protects those who do not have PC, is that many who have PC don't yet know it
Age at diagnosis 66, PSA 5.5
Biopsy 12/08 12 cores, 8 positive
Gleason 3 + 4 = 7
CAT scan 1/09 negative, Bone scan 1/09 negative

Robotic surgery 03/03/09 Catheter Removed 03/08/09
Post surgical pathology report. Lymph nodes negative, Seminal vesicles negative
Surgical margins positive, Capsular penetration extensive Gleason 4 + 3 = 7
At 6 weeks: 1 pad/day, 1 pad/night -- mostly dry at night.
At 10 weeks: no pad at night -- slight unpredictable leakage day/1 pad.


Tony Crispino
Veteran Member


Date Joined Dec 2006
Total Posts : 8128
   Posted 6/29/2009 9:06 AM (GMT -7)   
Thanks SHU,
I still trend towards the controlled studies that ruled out selenium as a preventive supplimentation. As will all suppliments, there is little factual data to go along with claims by the packagers. Consulting a doctor is the best way to determine if heavy supplimentation is safe and without negative interaction with prescription drugs, including hormone therapy and chemotherapy. Not to mention whether such certain suppliments will add fuel to an already buring fire...

Tony
 Age 47 (44 when Dx)
Pre-op PSA was 19.8 : Surgery at The City of Hope on February 16, 2007
Geason 4+3=7, Stage pT3b, N0, Mx
Positive Margins (PM), Extra Prostatic Extension (EPE) : Bilateral Seminal vesicle invasion (SVI)
HT began in May, '07 with Lupron and Casodex 50mg (2 Year ADT)
IMRT radiation for 38 Treatments ending August 3, '07
Current PSA (May 11, 2009): <0.1
 
My Journal is at Tony's Blog  
 
STAY POSITIVE!


Purgatory
Elite Member


Date Joined Oct 2008
Total Posts : 25353
   Posted 6/29/2009 11:05 AM (GMT -7)   
My own GP and I discussed this very subject last week when he was going over my blood work as part of my yearly physical (non PC related). He feels strongly that the selenium does nothing to prevent cancer in any way. He's really down on most supplements or natural herb remedies in general, he feels that all you get out of it is expensive urine, because of how the body flushes these items out. He also worries about legitimate meds becoming less effective because of how some vitamins, minerals, and other health supplements dilute the chemical composition and absortion of the meds.

David in SC
Age 56, 56 at DX, PSA 7/7 5.8, 7/8 12.3,9/8 14.5
3rd Biopsy Sept 08: Positive 7 of 7 cores, 40-90%, Gleason 7, 4+3
Open RP surgery 11/14/8, Right nerves spared, 4 days hospital, staples out 11/24/8, 5th cath out on 1/19/9
Post-surgery Pathlogy Report:Gleason 3+4=7, pT2c, 42 grm, tumor 20%, Contained in capsular, clear margins, clear lymph nodes 
First PSA Post Surgery   2/9 .05, 5/9 .10, 6/9 .11, July 13 - meet with radiation oncologist
 
 

New Topic Post Reply Printable Version
Forum Information
Currently it is Sunday, February 18, 2018 12:19 AM (GMT -7)
There are a total of 2,930,400 posts in 321,526 threads.
View Active Threads


Who's Online
This forum has 160277 registered members. Please welcome our newest member, asraphy.
292 Guest(s), 2 Registered Member(s) are currently online.  Details
Girlie, suchatravesty