Scientists have identified a gene which is mutated in 30 to 40 per cent of all breast cancers.
Researchers at Dana-Farber Cancer Institute found that the gene, IKBKE, is not inherited in a mutated form like breast cancer-susceptibility genes BRCA1 and BRCA2.
Instead, the mutation arises during the woman's lifetime and causes the IKBKE protein to be overproduced, leading to increased cell growth and production.
In order to find the new gene, the researchers used a new three-part screening process, described in the journal Cell, which the study authors believe could be used to identify more genes that play a role in the development of cancer.
Co-senior author Dr William Hahn, who conducts research at Dana-Farber, Brigham and Women's Hospital and the Broad Institute of Harvard and MIT, explained that many gene mutations can be involved in human cancers.
"In the current study, we used several complementary approaches to identify an important breast cancer gene," he revealed. "Each method helps 'filter' the information from the previous one, enabling us to zero in on the strongest candidate."
Dr Hahn continued: "This triple screening approach enabled us to study what happened to cells when IKBKE was turned on and when it was shut off, and to take a global look at the genetic alterations within breast cancer cell lines and tumours.
"Integrating these techniques allowed us to identify a new breast cancer oncogene and show that it plays a crucial role in the formation and survival of tumours."
The researchers hope that it may be possible to develop drugs which target IKBKE, shutting the gene down and potentially helping to treat a sizeable percentage of breast cancers.
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