Important link between cancer drugs and heart failure found by Winnipeg researchers

A Winnipeg doctor's cutting-edge research has found an important link between heart failure and cancer-fighting drugs, a finding that could help many battling the disease.

Jackie Ratz was diagnosed with Stage 3 Non-Hodgkin's Lymphoma at the age of 23 and given a 40 percent chance of survival.

After six rounds of chemo and some aggressive radiation treatments, Ratz had a clean bill of health, until about 20 years later.

Doctors found the treatments had damaged her heart, leading to heart failure.

"I had severe fatigue," recalled Ratz, "I still deal with shortness of breath. I lost my career because I wasn't able to do the day-to-day, so I'm on long-term disability for it. So it really changes everything."

It's a story all too common, according to Dr. Lorrie Kirshenbaum, director at the Institute of Cardiovascular at St. Boniface Hospital and director of research development at the University of Manitoba's Rady Faculty of Health Sciences.

Dr. Krishenbaum said the chemotherapy drug doxorubicin can weaken and damage the heart as a side effect.

The problem is the focus of his research, which his team recently published.

"The really exciting part about the research is the fact that we identified a particular protein that becomes degraded or inactive in cancer patients who are treated with a certain type of chemotherapeutic drug," said Kirshenbaum.

Dr. Kirshenbaum's research identified a protein called TRAF2 that stops functioning in cancer patients using doxorubicin.

He said the research took years to do and was extremely complex, but the potential impact is well worth it.

"We found that by replacing this defective protein, we could diminish or minimize the heart failure induced by the chemotherapy."

Dr. Kirshenbaum noted the research was in collaboration with St. Boniface Hospital, the University of Manitoba, the University of Toronto, the University of Washington, and Washington University in St. Louis.

The chemo drug examined in the research is commonly used to treat ovarian and breast cancer and some lymphomas.

Oncologist Dr. Marshall Pitz with CancerCare MB said the research is exciting, as a lot of his patients could benefit from it.

"Many of the patients I treat who have breast cancer are on medications that will affect their heart or have the potential to affect their heart, and breast cancer is very common, so the potential to impact many, many people," he said.

The research is also exciting to those who know the impact heart failure can have.

"It's wonderful. It's so, so exciting knowing women and men will be able to protect their hearts better than 20-some years ago," said Ratz, who started the Facebook support group Canadian Women with Medical Heart Issues after her experience.

Dr. Kirshenbaum said a more detailed analysis is now needed to explore its full potential.

He noted the research could lead to new therapies to treat heart damage from chemotherapy drugs and may have an effect on other cardiovascular diseases.

"Ultimately, the work that we do, we want to see translated to new therapies that can improve the quality of life for cancer patients," said Kirshenbaum.