As a child, Dr. Carrie Shemanko spent her afternoons and weekends exploring the forests and waterways surrounding her family’s grain farm near Rycroft, Alta.
“I ran wild in the outdoors and became fascinated by nature and biology,” she says.
It was the perfect training ground for her future career as a cancer researcher.
Shemanko first fuelled her fascination for nature and biology during her undergrad degree in genetics and her master’s degree in biochemistry at the University of Alberta. Next, she studied skin biology for her doctorate at the University of Dundee in Scotland. In the late 1990s, she did a post-doc fellowship at the Tumor Biology Center in Freiburg, Germany. It was there that she became interested in breast cancer, specifically understanding why many women who are treated for it also experience bone metastasis, the spreading of cancer into the skeletal system.
The statistics are troubling — 20 to 30 per cent of women who have been treated for breast cancer will experience metastasis, and 70 per cent of those women will experience bone metastasis, specifically. Shemanko’s research is focused on what happens once breast cancer cells reach the bone, and the damage they can cause once they’re there.
“It can take decades for the cancer cells that have spread to the bones to start to reproduce,” she says. “The cancer cells appear to spread to the bone early, but sit dormant for years.”
In 2002, Shemanko joined the faculty of science at the University of Calgary to lead a team of researchers dedicated to exploring the biology of breast-to-bone cancer in the lab.
“My main goal is to see if my research can be implemented clinically and change people’s lives,” she says.
Since 2008, Shemanko has also been a part of the Breast Cancer to Bone Metastases (B2B) Research Program — an initiative that established the tools and the patient resources that will help make her goal a reality. It was funded primarily from the Alberta Cancer Foundation’s former event, the Weekend to End Women’s Cancers.
The B2B program was started by Dr. Nigel Brockton, who was formerly a cancer epidemiologist with Alberta Health Services and now works at the American Institute for Cancer Research in Arlington, Va. The program is compiling resource data (tumour tissue, blood samples and lifestyle information) on 500 Alberta women who have been diagnosed with breast cancer. These women will be tracked over the long term to determine who will develop bone metastasis.
Shemanko led one of four miniprojects under the B2B umbrella. Her project examined the role of the hormone prolactin, which has been associated with breast cancer for years in the literature, in developing bone metastasis.
“My main goal is to see if my research can be implemented clinically and change people’s lives.” – Dr. Carrie Shemanko
The first phase of the project, which started in 2010 and was also supported by the Foundation, looked at breast cancer tissue from 140 women from the Prairies. Some of the women had already developed bone metastasis; others had not. Shemanko and her team measured levels of the prolactin receptor protein in each of the group samples. They found that women with high levels of prolactin receptor had been diagnosed with bone metastasis, likely due to bone pain or a fracture. Samples with low levels of the protein were not associated with bone metastasis.
The second phase involved applying bone cells and breast cancer cells grown in the lab for research purposes — some laced with prolactin, some with none — to slices of hippopotamus teeth, which have similar structural components to human bone.
“We make little, flat slices of the hippo tooth, then add bone cells to the top with an eyedropper, then breast cancer cells with an eyedropper, then allow them to interact,” she says. “If there are changes in the bone cells, it means they are trying to digest the tooth. The only way we can see this is by brushing the cells away with a toothbrush, then staining the tooth with a dye to see if there are pits.”
Shemanko and her team learned the group of teeth with prolactin-laced breast cancer cells caused changes to the bone cells and, subsequently, damage to the tooth. The cells with no prolactin did not.
In addition to confirming the link between prolactin protein receptors and bone metastasis, the team also drilled down further to identify a signature biomarker (the specific components are currently proprietary) that can be detected in blood. “This whole project was unique from start to finish,” says Shemanko.
Circling back to the 500-strong B2B cohort, she will now test participants’ blood samples — over time — for this biomarker and track whether it is predictive of developing bone metastasis. If women can be identified as high risk for bone metastasis, the next goal would be to determine if early treatment with targeted medications improves their outcome, as once breast cancer has metastasized into the bone, treatment becomes palliative.
“That is what drives me forward,” she says. “To try to make that change.”
In addition, in 2018, Shemanko joined co-principal investigator Karen Kopciuk in leading the B2B program. (Kopciuk first took over when Brockton left in 2017.)
Other research projects are also percolating. With funding from the Cancer Research Society, she is testing existing drugs to see which ones might be ultimately viable for bone metastasis. “We are trying to find drugs that have a known safety profile and are approved for clinical use,” she explains. “If successful, this will result in a drug getting from the lab to the clinic faster than starting from scratch.”
When out of the lab, she shares her passion and knowledge by teaching cell biology to students at the U of C.
Colleagues, including Brockton, are major fans of Shemanko and her work.
“Of course, she is a rockstar,” Brockton says. “Research progress demands tenacity and Carrie has worked tirelessly to reveal the secrets of how prolactin orchestrates both breast cancer cells and the bone microenvironments where breast cancer cells can take up residence. Despite her tenacity, she is uniquely human, faultlessly modest, open-minded and cares deeply about the plight of breast cancer patients.”
Although research does not always go smoothly, there is no deterring this rockstar.
“I am an eternal optimist,” she says. “You have to work hard and believe that you are doing something of value to get you through those rough spots. I can always see the light at the end of the tunnel.”
7 Questions with Dr. Shemanko
1. Describe what you do in 10 words or less.
Understand the biology of breast cancer spread to the bone.
2. What’s the biggest misperception about what you do?
Many people think scientists work in isolation, trying to solve a problem. Actually, we work with team members, often from different disciplines, to approach a problem from many vantage points.
3. Where do you get your best ideas?
Reading other scientific discoveries and also speaking with colleagues or students about what they have read or discovered is very helpful to stimulate new ideas.
4. If you weren’t a researcher, what would you be?
I love biology in general, so I’d probably do something in that area, but, if I could diverge, I might be a chef or baker.
5. What’s the hardest lesson you’ve learned?
Scientists very often experience rejection — rejection of a grant proposal that could fund their research and trainees or rejection of a scientific article that represents the lab results. I had to learn that these rejections aren’t the end, but can be overcome with additional work and perseverance.
6. What motivates you?
My love of learning and the knowledge that what I do could lead to improving patients’ lives.
7. What do you do to recharge?
I love being outside doing almost any activity — cycling, hiking or gardening.