Small molecules that restrain a selenium-containing enzyme in the human body may be a tool to fight cancer, says a study published in a U.S. medical journal.
The study published in Science Translational Medicine is based on findings of a research team at Karolinska Institutet in Sweden.
The team has treated cancer in laboratory mice with these molecules. After having observed the rapid tumor-killing effects of these molecules, the team hopes that the new principle for cancer treatment can be extended to treat the disease in humans, says a statement issued by the Karolinska Institutet.
Selenium is a chemical element that is an essential micronutrient. A selenium-containing enzyme, called TrxR1, can be used to support growth of various cells as it protects them from oxidative stress. Oxidative stress is the imbalance between production of free radicals – cells that are highly reactive with other molecules – and the body’s ability to counteract or to repair the resulting damage.
Since raised levels of TrxR1 can be detected in several forms of cancer, the researchers analyzed almost 400,000 different molecules for their ability to specifically control TrxR1. They found three different types which proved to be active as anti-cancer medicines. Using these molecules, they effectively treated over 60 different types of cancer cells under laboratory conditions. Normal cells, however, were much less sensitive to these molecules.
“This effectiveness against cancer may be a result of cancer cells’ seemingly greater sensitivity to oxidative stress when compared to normal cells, which in turn can be utilized in cancer therapy,” Prof. Elias Arner at Karolinska Institute has been quoted in the statement.
The statement says that new molecules have yet to be tested on humans, but it is already known that several different cancer medicines currently in use inhibit TrxR1. “Thus far, whether or not this inhibition of the enzyme is important to the effectiveness of these medicines has remained unknown, but this study suggests that this might well be the case.”
Research team now intends to further develop the new TrxR1 inhibitors to offer a new form of cancer therapy.
“My hope is that we will be able to develop new treatments, effective against multiple forms of cancer but with few side-effects. This seems to work in mouse models and we are therefore hopeful that this principle for treatment can be developed for humans, even if this will require many years of further research,” he said.