A new study led by Winnipeg researchers suggests that flipping a genetic switch could stop cancer cells from multiplying and heart cells from dying.

The study led by Dr. Lorrie Kirshenbaum of St. Boniface Hospital Research Centre is being published in the Proceedings of the National Academy of Sciences.

It reports the discovery of a master switch that regulates the "death gene" that tells cells when to live and die.

Kirshenbaum says scientists already knew the gene turns on in heart cells during a heart attack when oxygen levels drop.

He says the cells can't regenerate, and patients suffer from decreased heart function and eventually heart failure.

The same gene is turned off in cancer cells, which allows them to grow and multiply uncontrollably and spread throughout the body.

"It's quite exciting," Kirshenbaum told CBC News. "We've basically figured out how to switch on a particular gene that would ordinarily be activated when someone has a heart attack. What we think is cool is that in cancer this gene appears to be broken or nonfunctional.

"The idea is that if we understood how to switch on or switch off this gene we could potentially find new ways to treat individuals with cancer and heart disease."

Kirschenbaum said the discovery could lead to halting the progression of cancerous cells, and trigger cells to repair a damaged heart.

"When person is having a heart attack the cells of the heart become damaged," he said. "Heart muscle has limited ability to repair itself. We found this gene gets switched on [during a heart attack] and tells the cells to die — and our plan was to find a way to turn it off. With cancer it's just the opposite. And we found a way to switch it on."

"So the really remarkable component is the overlap between cancer and heart disease."

Kirshenbaum and his team tested heart and pancreatic cancer cells in the lab, not on humans or animals.

The discovery could help researchers develop drugs that will preserve heart function in heart attack patients and stop cancerous tumours from developing or spreading.