Family risk: 14 new breast cancer risk genes identified
Researchers have identified 48 genes whose activity is associated with breast cancer risk. Among them are 14 genes that have not yet been linked to breast cancer. Examination of these genes could provide further information about the tumor biology of breast cancer and possibly identify target structures for new therapies.
Cancer with the highest death rate
According to health experts, breast cancer is the cancer with the highest death rate among women in Germany. Nationwide, around 17,000 die of it every year and around 70,000 fall ill each year. There are still many unanswered questions about the causes of breast cancer, but according to the Cancer Information Service of the German Cancer Research Center (DKFZ), the following factors can be derived from large studies that influence a woman's risk of developing the disease: age, hormonal situation, lifestyle and possibly inherited risk genes. In a new study, researchers have now identified 48 genes whose activity is associated with breast cancer risk. Among them are 14 genes that have not yet been linked to breast cancer.
Increased family risk
As the DKFZ writes in a recent report, the family risk of women whose direct relatives have breast cancer is about twice as high as that of the general population.
A large number of genetic markers are already known which are associated with the increased risk. These markers are usually identified by so-called genome-wide association studies.
Researchers are examining millions of tiny genetic variants that differ from one another only in a single DNA building block (SNPs "single nucleotide polymorphisms") for an association with the risk of breast cancer.
“We are particularly interested in those SNPs that are associated with gene expression in breast tissue. We believe that they will help us identify genes that contribute to the development of breast cancer through changes in activity, ”says Jenny Chang Claude from the DKFZ.
In addition to numerous other colleagues from the DKFZ, the researcher is one of the authors of a study just published in the journal "Nature Genetics".
Genes involved in the development of breast cancer
The aim of the international project was to identify as yet unknown genes that may be involved in the development of breast cancer.
To this end, the researchers first identified SNPs that are associated with altered expression of individual genes. These SNPs were then examined for a relationship with breast cancer risk.
Over 160 research groups worldwide have been involved in the work, led by Wei Zheng from Vanderbilt University Medical Center in Nashville, Tennessee.
In total, genetic analysis of 229,000 women was included in the study, more than half of whom had breast cancer. Studies of such magnitudes are necessary in order to be able to make statistically reliable statements about the individual SNPs.
Important mechanisms in cancer development
In the end, the experts identified 48 genes whose altered expression is significantly associated with an increased risk of breast cancer. 14 of them were not yet known to be associated with breast cancer.
The researchers specifically switched off 13 of the 48 genes that had a particularly strong risk association in various breast cancer cell lines.
In eleven cases, this resulted in changes in cell growth and colony formation ability - both of which are important mechanisms in cancer development.
The scientists now want to characterize all genes identified in the study more precisely in terms of their functionality. They hope that this will give them a more precise understanding of the tumor biology of breast cancer.
It may also be possible to detect previously unknown cancer-relevant signaling pathways that could be blocked with targeted active ingredients. (ad)