Cancer-causing secret discovered

SCIENTISTS have uncovered one of the breast cancer-causing secrets of a gene that blights the lives of generations of related women.

The faulty gene not only causes breast cancer in up to 60% of those who inherit it, but also raises the risk of ovarian and prostate cancer.

In a finding that may have far-reaching implications for drug development, Cambridge University scientists have revealed how the so-called BRCA2 gene's interaction with other cells causes cancerous mutations.

The discovery is causing waves throughout the scientific community, according to Cancer Research UK, the Medical Research Council and the Wellcome Trust, which are funding the study.

As many as one in 200 women have an inherited mutation in one of two genes, BRCA1 and BRCA2, which greatly increases their chances of developing breast cancer. Carriers of the mutated genes are generally advised to have annual mammograms from the age of 25.

The research, the findings of which are published in science journal Nature today, concentrated on the BRCA2 gene.

Research leader Professor Ashok Venkitaraman, of the Hutchison/MRC Research Centre in Cambridge, said: "Understanding the nuts and bolts of BRCA2's function should in the future allow us to develop new types of anti-cancer drug."

Progress in this direction will take "more time and continued effort", Professor Venkitaraman warned, but drugs to block BRCA2's action could result in findings that make cancer cells more sensitive to therapies.

The research team explained in Nature that BRCA2 normally controls a molecule called Rad51, which is involved in repairing DNA and keeps the genes in a cell intact.

The research studied precisely how the BRCA2 protein molecule, produced from the gene, interacts with Rad51 and how the process goes wrong when BRCA2 is faulty.

Now that scientists know precisely how BRCA2 interacts with Rad51, they should be able to find ways of totally disrupting this interaction.

Paul Nurse, Cancer Research UK chief executive, said: "By focusing on the fine detail of the cancer-causing process, this study has given us a leap forward in our understanding of the disease on a molecular level. The work is not just an advance scientifically, but should also have a real impact on future cancer treatments."