Abstracted by Greg Arnold, DC, CSCS, from “Effects of selenium status and polymorphisms in selenoprotein genes on prostate cancer risk in a prospective study of European men”, printed online September 17, 2010 in Cancer Epidemiology, Biomarkers, and Prevention. Posted October 18, 2010.
Selenium is a trace mineral with recommended intakes ranging from 20-70 micrograms per day (1). Previous research has suggested a possible role for selenium in prostate cancer (2), which is the second most deadly cancer in men. There were 234, 460 new cases and over 27,000 deaths in 2006 (3). It has a 5-year survival rate of 100% if found early, but this rate plummets to 34% if found after it has spread (4). Now a new study (5) has suggested how selenium helps reduce prostate cancer risk.
In the study, 248 men between the ages of 40 and 64 with diagnosed prostate cancer from the EPIC-Heidelberg study (6) were compared with 492 men of similar age without prostate cancer. Blood samples were obtained from each patient to measure selenium levels as well as the activity of several selenium proteins (SEP15, SEPP1, GPX1, and GPX4S) which are “common markers” of selenium levels in the body as well as markers of oxidative stress and cell damage (7,8).
Patients having blood levels of selenium of 87-95 microgram/Liter had a 40% reduced risk of prostate cancer, compared to those with selenium levels below 78.9 micrograms/Liter. The risk for prostate cancer for blood levels above 95 microgram/L was significantly reduced (11%), compared to the 87-95 micrograms/Liter group. To try to explain this decrease, the researchers stated that 92 micrograms/L is the level that maximizes activity of the GPX1 protein (9), so having blood levels higher than 92 micrograms/L should not be expected to yield better results.
For the researchers, “Our results support a role of selenium and polymorphisms in [selenium proteins] in prostate cancer [causes], which warrants confirmation in future studies” and that “These findings might help to explain biological effects of selenium in prostate cancer development.”
- “Dietary Supplement Fact Sheet: Selenium” posted on http://ods.od.nih.gov/factsheets/selenium.asp
- Diwadkar-Navsariwala V. PN Selenoprotein deficiency accelerates prostate carcinogenesis in a transgenic model AS 2006 103: 8179-8184
- National Vital Statistics Report Volume 53, Number 5, released October 12, 2004
- “What Are The Key Statistics For Prostate Cancer?” posted on the American Cancer Society Website www.cancer.org
- Steinbrecher A. Effects of selenium status and polymorphisms in selenoprotein genes on prostate cancer risk in a prospective study of European men. Cancer Epidemiol Biomark Prev 2010; Sep 17. [Epub ahead of print]
- Boeing H, Korfmann A, Bergmann MM. Recruitment procedures of EPIC-Germany. European Investigation into Cancer and Nutrition. Ann Nutr Metab 1999;43:205-15.
- Gromadzinska J. Selenium and cancer: biomarkers of selenium status and molecular action of selenium supplements. Eur J Nutr 2008;47 Suppl 2:29-50
- Peters U. Selenium and the prevention of prostate and colorectal cancer. Mol Nutr Food Res 2008;52:1261-72
- Sieniawska CE. Determination of total selenium in serum, whole blood and erythrocytes by ICP-MS. Journal of Analytical Atomic Spectrometry 1999;14:109-12.