Aussie team discover rare breast stem cell responsible for tissue growth

Australian scientists have discovered the rare stem cell that drives the formation of all breast tissue.

By using a mouse model, researchers from the Victorian Breast Cancer Research Consortium have identified the breast stem cell which could provide clues about how breast cancer develops and how rogue cells evade current therapies.

The discovery will provide an important foundation for understanding how normal breast tissue develops.

Under normal circumstances, the newly discovered breast stem cell should produce healthy tissue, but the researchers believe an accumulation of genetic errors, perhaps combined with external influences and a family predisposition, could cause the breast stem cell or a "daughter" cell to produce faulty cells and becomes a virtual 'tumour factory'.

For many years, scientists and clinicians have been puzzled by the fact that women whose breast cancer cells have been apparently eliminated by chemotherapy sometimes experience a recurrence of their cancer.

A cancerous stem cell could provide one possible explanation for such a recurrence.

Current chemotherapy treatment works by targeting cells that are dividing rapidly, a typical feature of cancer cells.

However an errant stem-like cell may well be more resistant to chemotherapy because it divides more slowly.

Therefore while the chemotherapy can eliminate the bulk of cancer cells, the tumour factory itself, a rogue breast cancer stem cell, may survive for years.

Within the wide context of international breast cancer research, the discovery of this breast stem cell is significant and will probably provide the basis of research in the future.

Breast cancer research strives to create a drug that will, in effect, switch off breast cancer cells.

In order to do this, the exact makeup of genes expressed by normal and rogue stem cells will need to be established before a drug can be designed to engage with and neutralize the faulty feature of the stem cell.

The Australian team is presently conducting further research on excised human breast tumours to confirm their findings derived from the mouse model.

The research team is from the WEHI Group of the Victorian Breast Cancer Research Consortium, which is funded by the Victorian state government through the Cancer Council Victoria.