Having enough Selenium considerably reduces the risk of kidney bladder cancer in specific but large groups of people

December 04, 2008

Selenium is a mineral actively utilized by antioxidant systems and detoxification systems in our body. A number of studies indicate that particular forms of selenium decrease the risk of a number of cancers. Increased levels of selenium may reduce a woman’s risk of bladder cancer by 34 % according to a new study from Dartmouth Medical School. The Ivy League researchers also report a significant reduction in risk for moderate smokers and people with a cancer related to a specific gene – p53. Other studies have already reported a similar connection between selenium and decreasing incidence of bladder cancer among women, but the new results, published in the December issue of Cancer Prevention Research, are said to be the first to show an association between selenium and protection from p53 positive bladder cancer. P53 is a protein that triggers the activation of genes that cause the destruction of dangerous cells. If P53 doesn’t work the genes drop out of the cancer fighting business. In cancers where P53 doesn’t work to protect us the tumours are more formidable.
"Ultimately, if it is true that selenium can prevent a certain subset of individuals, like women, from developing bladder cancer, or prevent certain types of tumours, such as those evolving through the p53 pathway, from developing, it gives us clues about how the tumours could be prevented in the future and potentially lead to chemopreventive efforts," said lead researcher Margaret Karagas.
Dr Karagas and her co-workers measured selenium levels in the toenails of 767 people newly diagnosed with bladder cancer (76 % male, average age 62) and 1,108 people from the general population (61 % male, average age 61). While no associations were found between selenium levels and bladder cancer risk for the whole population group, significant reductions in risk were found for women (34 %), moderate smokers (39 %) and those with p53 positive cancer (43 %).

"There are different pathways by which bladder cancer evolves and it is thought that one of the major pathways involves alterations in the p53 gene," said Karagas. "Bladder cancers stemming from these alternations are associated with more advanced disease." The study is published in the December 2008, issue of Cancer Prevention Research.