Title: Should antioxidants, vitamin E, be administered along with edelfosine to cancer patients?
Subject: Medicine & Health
Grade level: High School - Grades 10-12
Academic Level: Advanced
Project Type: Experimental
Gold Medal and Calgary Medical Society Award, 2010 Calgary Youth Science Fair
Second Place, Canada Wide Virtual Science Fair ($100)
Affiliation: Canada Wide Virtual Science Fair
Materials and Techniques: Petri plates, autoclave, bunsen burner, spark-starter, vortex, spectrophotometer, YPD plates, wild type yeast, edelfosine, α-tocopherol (vitamin E).
Description: Edelfosine (an anticancer drug) and vitamin E (added together) effects were tested on yeast cells. If α-tocopherol (vitamin E) prevents edelfosine from killing the yeast cells, then there is a very good chance that it is because oxidative stress is occurring and the meaning is that administering vitamin E along with edelfosine in humans as a form of chemotherapy would be ineffective. .
Vitamin E and Cancer Prevention
As of 2009, human trials and surveys that have investigated potential association of vitamin E intake with incidence of cancer remain generally inconclusive. Antioxidants such as vitamin E help protect against the damaging effects of free radicals, which may contribute to the development of chronic diseases such as cancer. Vitamin E also may block the formation of nitrosamines, which are carcinogens formed in the stomach from nitrites consumed in the diet. It also may protect against the development of cancers by enhancing immune function.
Some evidence associates higher intake of vitamin E with a decreased incidence of prostate cancer (see ATBC study) and breast cancer. Some studies correlate additional cofactors, such as specific vitamin E isomers, e.g. gamma-tocopherol, and other nutrients, e.g. selenium, with dramatic risk reductions in prostate cancer. However, an examination of the effect of dietary factors, including vitamin E, on incidence of postmenopausal breast cancer in over 18,000 women from New York State did not associate a greater vitamin E intake with a reduced risk of developing breast cancer. A study of the effect on lung cancer in smokers also showed no benefit.
Recent studies have found that increased intake of vitamin E, especially among smokers may be responsible for an increase in the incidence of lung cancer, with one study finding an increase in the incidence of lung cancer by 7% for each 100 IU of vitamin E taken daily.
A potential confounding factor is the form of Vitamin E used in these studies. As explained earlier, synthetic, racemic mixtures of Vitamin E isomers are not bioequivalent to natural, non-racemic mixtures, yet are widely used academically and commercially. The SELECT study for prostate cancer used racemic alpha-tocopherol, for instance, and has shown no benefit. The study, cited above, showing a modest increase in cancer risk with Vitamin E supplementation, reported that over 90% of its respondents used a racemic form of Vitamin E (d,l-alpha-tocopherol). A meta-analysis of studies using Vitamin E, sorting results by the form (racemic vs non-racemic) used, is necessary.
See also: http://en.wikipedia.org/wiki/Tocopherol
Source: Wikipedia (All text is available under the terms of the GNU Free Documentation License and Creative Commons Attribution-ShareAlike License.)