During the development of an embryo, formation of organs is tightly controlled by specific genes. In the case of breasts, this process controls the development of two breasts in humans but this can go awry, resulting in fewer, extra or misplaced breasts or nipples. However, little has been known about this how this process is governed, until now.
Today scientists at The Breakthrough Toby Robins Breast Cancer Research Centre, at The Institute of Cancer Research, report that a gene called Scaramanga - aptly named after the three-nippled villain from the James Bond film The Man with the Golden Gun - is involved in triggering breast development.
"Identifying the Scaramanga gene is a real advance in our understanding of the early steps in breast formation. By learning more about this gene and the protein it produces, it will allow us to determine how normal breast development is initiated and, importantly, examine how this is connected with breast cancer," said Professor Alan Ashworth, Director of The Breakthrough Breast Cancer Research Centre.
By studying abnormal breast development in the lab, scientists at The Breakthrough Breast Cancer Research Centre identified the Scaramanga gene, which regulates the early stages of breast development, and influences the number and position of breasts. The realisation of the importance of their work came when they discovered that the Scaramanga gene produces a protein called NRG3 and that this provides a signal telling embryonic cells to become breast cells. They also showed that a synthetic form of NRG3 was able to initiate the formation of breast cells, confirming the protein's involvement in this intricate process.
Professor Ashworth continued: "Whilst proteins carefully control the development of breast cells in the embryo, inappropriate signals to breast cells during adulthood by these same molecules may cause breast cancer. We already believe that the protein produced by the Scaramanga gene is linked with breast cancer and the next steps are to study this in more detail."
Like the gene's namesake, Scaramanga, 1 in 18 people have an extra nipple**, which can resemble freckles or moles. This is a normal occurrence and does not mean anything is wrong with the person but it's important that this extra tissue is checked for abnormalities like all breast tissue.
This is just one example of the groundbreaking research, funded by Breakthrough Breast Cancer's generous supporters, taking place at The Breakthrough Toby Robins Breast Cancer Research Centre. The centre, Europe's only facility dedicated to breast cancer research, has been producing pioneering research for just over five years. It is based in the Mary-Jean Mitchell Green Building at The Institute of Cancer Research.
In less than five years, the centre has launched The Breakthrough Generations Study - the largest investigation ever into the causes of breast cancer, involving 100,000 women over 40 years - and has discovered a potential new targeted drug, called a PARP inhibitor, for women with a type of hereditary breast cancer, which is currently in clinical trials.