Scientists in London have identified the master switch controlling a protein associated with the spread of breast cancer around the body. They believe their discovery could lead to more effective treatment of aggressive breast cancers, enabling them to target treatments more specifically.
The work, funded by the Association for International Cancer Research and Breast Cancer Campaign (BCC) and published on 15th April 2005 identified how the protein HSP27 is increased in these cancer cells. Breast cancers with a higher level of this protein normally spread faster and are more resistant to current drug treatments, resulting in fewer patients surviving the disease.
A team from University College London, in collaboration with other colleagues-particularly from St Thomas's and Guy's Hospitals-found increased levels of a master switch protein called Brn-3b acted directly to make the breast cancer cells produce more HSP27. Conversely when it was removed, they registered decreased levels of HSP27. This, in turn, significantly modified the behaviour of the cancer cells, making them more likely to spread and be resistant to chemotherapy.
Dr Vishwanie Budhram-Mahadeo, who led the team from UCL explained: "By analysing proteins in biopsies taken from patients with breast cancer and comparing them to biopsies from normal or benign breast tissue, we were able to show a striking correlation of Brn-3b with the high levels of HSP27 protein in the diseased tissue. Brm-3b boosts the invasiveness of cancer cells, and contributes to the deadly nature of this disease. We can now work out strategies to deal with cancers with increased Brn-3b without adversely affecting the healthy cells around it that do not express high levels of the protein."
Norman Barrett, Chief Executive of the Association for International Cancer Research added:"These studies will pave the way for future research in which we can treat patients on the basis of the molecular fingerprint that will be specific and unique to every individual. This will allow therapy to be tailored to treat patients whose tumours have high levels of Brn-3b to reverse the growth of cancer cells while minimising the undesirable side effects of conventional therapies."
Pamela Goldberg, Chief Executive of the Breast Cancer Campaign (BCC) said, "In the same way that breast cancer is not one disease, there will not be one cure. Each patient's breast cancer is different and it is only through advances in our understanding of the basic molecular changes that occur in cells to turn them cancerous that we will make progress in developing more effective methods of diagnosis and treatment of breast cancer and hopefully help us prevent the disease in all women."