A pathway linked to a gene called PTEN is important for the growth of breast cancer stem cells, according to scientists at the University of Michigan Comprehensive Cancer Center.

In the same study, the researchers have also found that a drug that interferes with that pathway can lead to an up to 90 percent decrease in the number of cancer stem cells within a tumour.

Reporting their finding sin the journal PLoS Biology, the researchers pointed out that PTEN is the most frequently inactivated tumour suppressor gene in several cancers, including breast cancer, where it is inactivated in about 40 percent of patients.

The researchers also highlighted the fact that PTEN is linked to poor outcomes and is associated with aggressive cancers resistant to chemotherapy and current targeted therapies.

During the study, they deleted PTEN in tumours grown in cell cultures and in mice, and found an increase in the number of stem cells.

Looking at pathways associated with PTEN, the researcher found that a pathway called PI3-K/Akt regulated the cancer stem cell population by activating another stem cell pathway, Wnt, which is also implicated in multiple cancer types.