Scientists discover gene switch important in cancer

November 1, 2012

Scientists at Karolinska Institutet in Sweden and the University of Helsinki in Finland have shown that the "switches" that regulate the expression of genes play a major role in the development of cancer. In a study, published in Science, they have investigated a gene region that contains a particular single nucleotide variant associated with increased risk for developing colorectal and prostate cancers – and found that removing this region caused dramatic resistance to tumor formation.

Genome-wide association studies have revealed genomic regions associated with more than 200 diseases, including heart disease, diabetes and different . The unveiled has attracted much attention in both scientific and popular press. However, the mechanisms by which these genomic regions act are not fully understood. One suggestion that has generated considerable interest is the possibility that the risk polymorphisms located far from genes could function as gene or "switches" that regulate the expression of genes.

In the current study, which was conducted in mice, scientists have analyzed one particular single nucleotide variant in a region associated with increased risk for developing colorectal and , but whose mechanism of action has been unclear. Although this variant increases only by 20 per cent, it is very common and therefore accounts for more inherited cancer than any other currently known genetic variant or mutation.

The scientists removed the gene region containing the risk variant from the mouse genome, and found that as a result the mice were healthy but displayed a small decrease in the expression of a nearby , called MYC. However, when these mice were tested for the ability to form tumours after activation of an oncogenic signal that causes colorectal cancer in humans, they showed dramatic resistance to tumor formation. The removed gene region thus appears to act as an important gene switch promoting cancer, and without it tumors develop much more rarely.

According to the scientists, these results show that although the gene variants – which make individual humans different from each other – in general have a small impact on disease development, the gene switches in which they reside can play a major role.

"Our study also highlights that growth of normal cells and cancer cells is driven by different gene switches, suggesting that further work to find ways to control the activity of such disease-specific switches could lead to novel, highly specific approaches for therapeutic intervention", says Professor Jussi Taipale, who led the study.

Explore further: Gene variant linked with reduced lung cancer risk

More information: "Mice Lacking a Myc Enhancer Element that Includes Human SNP rs6983267 Are Resistant to Intestinal Tumors", Sur, I., Hallikas, O., Vähärautio, A., Yan, J., Turunen, M., Enge, M., Taipale, M., Karhu, A., Aaltonen, L. A., and Taipale, J., Science, in press, online 1 November 2012.

Related Stories

Gene variant linked with reduced lung cancer risk

October 8, 2012
A variant in a gene involved with inflammation and the immune response is linked with a decreased risk of lung cancer. That is the finding of an analysis published early online in Cancer, a peer-reviewed journal of the American ...

Blood clotting and bowel cancer risk

June 6, 2011
Back in the mid 19th century, a French doctor, Armand Trousseau, discovered a connection between cancer and thrombosis – the formation of often dangerous blood clots that can lead to venous occlusion. Today it is known ...

New gene variants raise risk of neuroblastoma, influence tumor progression

September 4, 2012
Researchers have discovered two gene variants that raise the risk of the pediatric cancer neuroblastoma. Using automated technology to perform genome-wide association studies on DNA from thousands of subjects, the study broadens ...

Recommended for you

Outdoor light at night linked with increased breast cancer risk in women

August 17, 2017
Women who live in areas with higher levels of outdoor light at night may be at higher risk for breast cancer than those living in areas with lower levels, according to a large long-term study from Harvard T.H. Chan School ...

Scientists develop novel immunotherapy technology for prostate cancer

August 17, 2017
A study led by scientists at The Wistar Institute describes a novel immunotherapeutic strategy for the treatment of cancer based on the use of synthetic DNA to directly encode protective antibodies against a cancer specific ...

Scientists develop blood test that spots tumor-derived DNA in people with early-stage cancers

August 16, 2017
In a bid to detect cancers early and in a noninvasive way, scientists at the Johns Hopkins Kimmel Cancer Center report they have developed a test that spots tiny amounts of cancer-specific DNA in blood and have used it to ...

Toxic formaldehyde is produced inside our own cells, scientists discover

August 16, 2017
New research has revealed that some of the toxin formaldehyde in our bodies does not come from our environment - it is a by-product of an essential reaction inside our own cells. This could provide new targets for developing ...

Cell cycle-blocking drugs can shrink tumors by enlisting immune system in attack on cancer

August 16, 2017
In the brief time that drugs known as CDK4/6 inhibitors have been approved for the treatment of metastatic breast cancer, doctors have made a startling observation: in certain patients, the drugs—designed to halt cancer ...

Researchers find 'switch' that turns on immune cells' tumor-killing ability

August 16, 2017
Molecular biologists led by Leonid Pobezinsky and his wife and research collaborator Elena Pobezinskaya at the University of Massachusetts Amherst have published results that for the first time show how a microRNA molecule ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.