Molecular Profiling of Breast Tumour Stem/Progenitor Cells (2007-2010)

Breast cancer is the commonest cancer in women in many countries including Australia, the USA and the UK. The incidence of breast cancer has been increasing over the last decade however mortality from breast cancer has declined. Although there is debate as to the exact reasons for this decline in mortality, it is clear that the introduction of the screening program as well as improvements in treatment have played a significant role. Nevertheless, a proportion of patients will have disseminated disease at presentation and may not fully respond to treatment. In addition a number of patients will go on to form apparent recurrence of the primary tumour and/ or distant metastases following what appears to be complete clearance of a tumour. In recent years a new concept has been put forward that might account for some of these recurrences. It is thought that the cells in a tumour do not all divide at the same rate. Instead some cells only divide rarely, and then give rise to other cells which divide rapidly and form the bulk of the tumour. Since these 'tumour stem cells' are slow cycling they will be resistant to existing chemotherapy because this affects rapidly dividing cells. These resistant cells may then go on to form another tumour. We intend to study these 'tumour stem cells' using a range of techniques that will show us how they differ from both the rest of the tumour cells and the different types of normal cells in the breast. By identifying molecules that are different in the tumour stem cells we will then have new targets for therapies that are designed to target these chemotherapy-resistant cells. Such therapies could be used in the future in conjunction with existing therapies to achieve a greater eradication of breast tumours.