Montreal researchers find protein that could slow breast cancer metastases

A team from the Montreal Clinical Research Institute has identified a protein that could play a role in the spread of breast cancer cells throughout the body.

We could therefore consider targeting this protein to slow the appearance of metastases, the researchers believe.

“One thing all breast cancers have in common is that when the disease progresses to the metastatic stage, that’s when it begins to pose a threat to patients’ health and survival over time,” said Professor Jean-François Côté. “That’s why our research program is very interested in understanding metastases.”

This work, he added, has led to a “series of discoveries” to understand how cancer cells are able to leave the primary tumor, invade blood vessels or lymphatic vessels, and then go on to colonize secondary organs such as the lung.

Once the primary tumor is removed, explained Professor Côté, who is also the president and scientific director of the IRCM, “the damage is already somewhat done” since there are already cells that have spread throughout the body and entered a state called “tumor dormancy.”

While some of these cells can remain dormant for 10 or 20 years, others can wake up after only a few months.

The most recent discovery by Professor Côté and his team concerns a protein called PIK3C3, which appears to be essential for the survival of these cells capable of remaining inactive for long periods.

“We were trying to understand a little bit about the vulnerability of cells that have gone to hide in secondary organs,” he explained. “What genes are essential for their survival? Could we start eliminating these cells that have spread throughout the body?”

Laboratory experiments first demonstrated that cancer cells struggle to survive when PIK3C3 is inhibited with drugs or a genetic approach. Tests on mice then revealed that these drugs can also eliminate these cells in the lungs of the small creatures.

“We think we have shown an example of a gene that is truly required, at least in the models we have tested in the laboratory, for the survival of cells in secondary sites,” summarized Professor Côté.

This gene could become a therapeutic target in the coming years, he believes. For example, one day, it might be possible to treat a woman undergoing breast cancer to minimize the risk of metastases.

“We could carry out a second wave of treatments that could really change the quality of life and then the survival of patients,” predicted Professor Côté.

It is estimated that one in four women who develop breast cancer will eventually experience a recurrence of the disease.

The lead author of this study published in the journal Cancer Research is Dr. Islam E. Elkholi, also from the IRCM.

–This report by La Presse Canadienne was translated by CityNews