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Kidney cancer discoveries open new avenue for treatment

OICR-supported researchers have identified a promising therapeutic target for clear cell renal cell carcinoma.


By blocking the function of a protein that helps kidney cancer grow, OICR-supported researchers may have found a promising new way to slow down the disease.

Clear cell renal cell carcinoma (ccRCC) is the most common type of kidney cancer, as well as the deadliest.

But in recent years, researchers like OICR Investigator Dr. Laurie Ailles have found growing evidence of vulnerabilities in how ccRCC cells function that could be exploited with new medications.

In the latest discovery from Ailles’ lab, published in Nature Communications, researchers found that stopping the activity of a protein called PRMT1 stops kidney cancers cells from replicating, and eventually causes them to die.

“Our hope was to identify a new target that could provide a scaffold for drug development for ccRCC,” says Ailles, who is also a Senior Scientist at the Princess Margaret Cancer Centre and an Associate Professor in Medical Biophysics at the University of Toronto.

PRMT1 comes from a family of proteins that regulate important functions in a cell. Based on earlier research, Ailles and colleagues theorized that ‘inhibiting’ these proteins might end up damaging cancer cells.

They tested their theory using a library of compounds that inhibit these types of proteins acquired from the Structural Genomics Consortium, and came away with a promising ‘hit’: PRMT1.

Dr. Joesph Walton

“It looks like there’s a phenotype where, when PRMT1 is inhibited, cancer cells begin to take on a lot of DNA damage, they stop cycling and eventually they die,” says Dr. Joseph Walton, a postdoctoral researcher in Ailles’ lab and the study’s first author.

Their findings about PRMT1 are especially promising for a couple of reasons.

First, the research was done using ‘patient-derived cell lines’ developed by Ailles’ lab. These are research models created from the cells of actual cancer patients, meaning they more accurately reflect human biology. The cell lines Ailles created also have the advantage of being new, compared to models created decades ago, which may have evolved biologically the over the years.

“By using our patient-derived cell lines, we feel that our models are much more representative of what’s actually helping patients,” Ailles says.

It’s also encouraging that therapeutics inhibiting PRMT1 are already in development for other types of cancer, meaning this research has a faster track toward making an impact on patients.

“Hopefully the data from these other studies could help our work translate more quickly to the clinic,” says Walton.

Ailles, Walton and colleagues are now investigating how inhibiting PRMT1 could work in tandem with existing cancer therapeutics that cause DNA damage, like chemotherapy and radiation. They are also exploring other ways to inhibit the PRMT1 ‘pathway’, which could ultimately lead to even better therapeutic candidates that may be safer and more effective for patients.

Ailles says these discoveries wouldn’t have been possible without her OICR Investigator Award.  She says OICR was especially helpful in developing the patient-derived cell lines – the kind of foundational science that drives discovery but can be difficult to get funding for.

“I can’t say enough how instrumental OICR has been in this project, and in so much of my work,” Ailles says.

Longtime OICR Executives to lead Institute through important new chapter

Dr. Christine Williams and Dr. Lincoln Stein will co-lead OICR on an interim basis alongside the Institute’s 350+ staff and province-wide network of partners and researchers

With extensive leadership experience and the support of Ontario’s thriving cancer research community, Dr. Christine Williams and Dr. Lincoln Stein are ready to lead OICR toward even greater impact.

The longtime OICR Executives were appointed the Institute’s Acting President and Acting Scientific Director in October, after Dr. Laszlo Radvanyi moved on from his position as President and Scientific Director.

“Lincoln and I are grateful to OICR’s staff, Board of Directors, and partners in the Government of Ontario for their trust in us, and humbled by the support of OICR’s many collaborators,” says Williams, who assumes the role of President (Interim). “OICR has built a tremendous network across Ontario, and we look forward to working closely with our partners to continue leading groundbreaking research and delivering solutions that improve the lives of people affected by cancer.”

Williams joined OICR in 2016 as Deputy Director and was most recently OICR’s Executive Vice-President and Head of Implementation Science. An immunologist with a special interest in childhood cancers, Williams is also Executive Director of ACCESS – a national research network for pediatric cancer – and has previously held leadership positions at the National Cancer Institute of Canada and the Canadian Cancer Society.

Stein joined OICR in 2007, after establishing himself as a leader in genome informatics at the Cold Spring Harbor Laboratory and the Massachusetts Institute of Technology (MIT). He has since built and led programs that have made OICR a world leader in informatics, computational biology and data sharing, including several international cancer data sharing initiatives. Stein was most recently OICR’s Deputy Scientific Director and Head, Adaptive Oncology.

Both Williams and Stein were integral to the development of OICR’s current Strategic Plan, and will continue to lead its execution. They will also bring their vision and expertise to finalizing OICR’s Strategic Plan 2026-2031, which is currently being developed in consultation with patients, clinicians, scientists and other stakeholders.

“The technological developments in recent years – including everything from artificial intelligence to liquid biopsies – have made this an exciting time for cancer research,” says Stein, OICR’s new Scientific Director (Interim). “With our tremendous capacity in areas like genomics, bioinformatics and drug discovery, and deepening connections with patients and clinicians, OICR is well positioned to drive even more innovations and continue making Ontario a global leader in cancer research.”

Williams and Stein will remain in their interim positions as OICR recruits a permanent President and Scientific Director. They will also continue in their roles as Head of Implementation Science and Head of Adaptive Oncology, respectively.

“Christine and Lincoln are both highly skilled leaders with deep relationships throughout the Institute and across the Ontario research community,” says Susan Fitzpatrick, Chair of OICR’s Board of Directors. “I am confident they will provide the Institute with strong and steady leadership.”

OICR researchers inducted into Royal Society of Canada

Dr. Mathieu Lupien and Dr. Trevor Pugh received the prestigious honour for their significant achievements in cancer research.


Two OICR scientists have been honoured as leaders in their fields by the Royal Society of Canada (RSC).

In a ceremony on Nov. 8 in Vancouver, the RSC inducted Dr. Mathieu Lupien as a Fellow of the Society, while Dr. Trevor Pugh was named a College Member.

The RSC recognizes leaders from across the country for their accomplishments to help build a better world. RSC Fellows are elected by their peers for outstanding scholarly achievements, while College Members are mid-career leaders appointed for addressing major challenges in their field.

Pugh is an OICR Senior Investigator and Director of the Institute’s Genomics program, as well as Senior Scientist at Princess Margaret, Professor in UofT’s Department of Medical Biophysics and Canada Research Chair in Translational Genomics. He is world-renowned cancer researcher and clinical molecular geneticist using genome sequencing to understand the causes of cancer, guide patient treatment, and detect early disease using blood tests.

“I am grateful for this recognition, and for the many brilliant people who have supported my work and helped push it forward,” Pugh said. “Together, we are harnessing the power of genome sequencing to detect, diagnose and treat cancer in new ways that will impact patients at all stages of their cancer journey. I look forward to continued collaboration with patients, clinicians, scientists, and new colleagues in the RSC to ensure everyone confronting cancer benefits from Canada’s investment in research.”

Lupien is an OICR Investigator, Senior Scientist at the Princess Margaret Cancer Centre and Professor of Medical Biophysics at the University of Toronto (UofT). His pioneering research into epigenomics and genome indexing has led to the discovery of new classes of non-coding DNA elements and associated epigenetic variations to reveal their role in disease etiology. His work has also led to the adoption of epigenomics technology in clinical settings to benefit cancer patients.

“I am deeply honoured and humbled to be a newly elected Fellow of the Royal Society of Canada,” Lupien said. “This recognition is a testament to the exceptional support and engagement of my colleagues, mentors, trainees and friends, who have joined me in exploring the fundamental nature of cancer. With their support, my research has aimed to challenge the traditional view of cancer as a purely genetic disease, proposing instead an epigenetic perspective that regards cancer as a disease of the chromatin, where epigenetic-based therapy is key to managing the disease.”

Read more about the 2024 inductees in RSC’s news release.

Internship comes full circle for Métis student researcher

OICR sponsored University of Toronto undergraduate student Mesai James for the 2024 BioCanRx Indigenous Summer Student Internship.

Mesai James has already seen his hard work this summer pay off.

The third-year University of Toronto undergrad spent his summer break doing a four-month internship in the lab of OICR Senior Investigator Dr. Robert Rottapel.

Through the internship, James made meaningful contributions to innovative research into potential new drugs to treat high-grade serous ovarian cancer, while also learning theory and practical skills related to biology and drug discovery research.

And many of these topics have come up in his university courses this fall.

“Things have been coming full circle in my classes, and it really reinforces my experience in the lab this summer,” says James, who is studying for his Bachelor of Science with a double major in immunology and neuroscience.

James’ internship was offered through the BioCanRx Indigenous Summer Student Internship program, an OICR-supported initiative that provides Indigenous students with hands-on research or policy experience.

James, a Métis from the Eastern Woodland Métis Nation, says these kinds of opportunities are important for Indigenous youth, who may not otherwise see a career in science as an option.

OICR News spoke to James about his background in science, his internship experience, and his plans for the future.

How did you decide that you wanted to study sciences?

Growing up I wasn’t really interested in science. I wasn’t sure what I wanted to do or be when I grew up. I always loved drawing and reading. But I learned from my great-grandmother, who lived and worked in Nova Scotia and spoke about her experiences working in a hospital with young people facing mental challenges, and I found myself drawn to healthcare. Then, in high school, I developed an interest and fascination for biology and chemistry in my classes. I was always asking why – why does this element react with this other one? And then my interest grew.

How did you get involved in cancer research?

I got involved in cancer research because I wanted to learn more about science. I was drawn to subjects like genetics and epigenetics in my late high school years and then was given a couple of opportunities through internships with the University of Toronto and SickKids Hospital. Last year, I had the opportunity to intern at the Rottapel lab, and to work on this drug discovery project in ovarian cancer. It was a wonderful experience, and I am so grateful for the BioCanRx internship for allowing me to continue my research in the lab this year. The internship has allowed me to grow in my knowledge of cancer research.

What sort of skills did you gain during your internship that will be helpful for your future?

The skills I gained during my internship that will be helpful for my future include procedures like western blotting and cell culturing. This year, I was able to build on those skills and techniques by learning about bacterial culturing and RNA extraction, for example. These and other techniques will be helpful in my future career, and they have recently come up in a few of my university classes. Because of the internship, I know how to do certain procedures and techniques and have gained an understanding of the theory behind them. So, I’m having a lot of full circle moments thanks to my experience this summer.

Speaking of the future, what are your plans for after your studies?

In the future, after my studies, I plan to work in healthcare, whether as a medical doctor or a scientist or both. I think doing health research and helping turn that research into medicine would be very gratifying to me and others. I do want to be able to share my research work within Canada and maybe across the world. I see myself being happy doing that.

Why are these internship opportunities important for Indigenous youth?

There is a great importance in providing intern opportunities for Indigenous students as it provides a view into a company or organization that may not have been viewable to an Indigenous youth. I grew up in a predominantly white neighbourhood and wasn’t fortunate enough to be given opportunities without seeking out different avenues to gain experience and knowledge like this one. I never saw people who looked like me doing science in Canada. I feel that other young Indigenous youth maybe feel deterred from entering into the sciences field because they don’t see themselves represented – whether it’s in the media or in actual labs. These kinds of internships improve representation and increase opportunities for the next generation and the generations to come, and they also make research better by making it more inclusive.

Ask a Cancer Researcher: How does the gut microbiome impact cancer?

Dr. Saman Maleki talks about the gut microbiome in relation to cancer. Learn why a microbiome transplant might be important for patients undergoing immunotherapy.

Ontario Institute for Cancer Research funding aims to speed the development of new drugs for some of the most common cancers

OICR’s Cancer Therapeutics Innovation Pipeline will support four new projects to accelerate development of drugs for brain, breast and blood cancers

October 2, 2024, TORONTO – The Ontario Institute for Cancer Research (OICR) continues to support Ontario drug discovery research by funding high-quality investigations of new therapies for some of the most prevalent pediatric and adult cancers. These projects are tackling substantial challenges in cancer by increasing the effectiveness and availability of immunotherapies, making cancer more vulnerable to chemotherapy and developing a new drug for one of the deadliest forms of childhood brain cancer.

OICR’s Cancer Therapeutics Innovation Pipeline (CTIP) initiative is supporting three research teams with up to $300,000 each to conduct Early Validation projects and another with up to $1 million for a Late Accelerator project. Early Validation projects aim to lay the groundwork for future therapies by accumulating evidence that ‘targeting’ specific molecules in cancer cells have the potential to become a therapy for cancer patients in the future. Late Accelerator projects aim to speed the creation of new drugs that act on relevant, validated cancer targets.

CTIP’s committee of experts from academia and industry reviews initial applications for funding and provides scientific and strategic advice to the funded research teams to help them advance their discoveries and offer guidance on attracting the partnerships and investments needed to bring new drugs to the clinic.

“Ontario is home to some of the world’s best drug discovery researchers and we are proud to provide them with this support to see that the newest precision cancer treatments reach patients as soon as possible,” said Dr. Laszlo Radvanyi, OICR’s President and Scientific Director. “This funding will also help further strengthen drug discovery research in the province and boost collaboration in our cancer research community.”

“Ontario is proud to support the work of OICR and programs like the Cancer Therapeutics Innovation Pipeline that lead to new discoveries and innovations in cancer research,” said Nolan Quinn, Minister of Colleges and Universities. “It is very encouraging to see promising new therapies like these that have the potential to help patients beat some of the most common types of cancer and lead longer and healthier lives.”

Funded projects

Early Validation

Targeting the interferon pathway to treat chronic leukemias and other blood cancers

  • Principal investigators: Dr. David Spaner, Sunnybrook Research Institute and Dr. Theodore Brown, Mount Sinai Hospital/Lunenfeld-Tanenbaum Research Institute
  • Project summary: This project aims to develop new, targeted medications to make leukemia cells more susceptible to chemotherapy with reduced side effects. The drugs would prevent leukemia cells from producing a molecule called interferon, which helps them grow and strengthens their ability to resist chemotherapy. Drugs that are currently available to block the effects of interferon have many side effects since interferon is also produced by healthy cells and is important in fighting infections.

Identifying an MLH1 small molecule inhibitor for combination with immune checkpoint inhibitors

  • Principal investigators: Dr. Saman Maleki, Lawson Health Research Institute and London Health Sciences Centre, Dr. Masoud Vedadi, OICR and Dr. Rima Al-awar, OICR
  • Project summary: Most cancers do not respond to immunotherapy, a powerful and relatively new form of treatment. This project is undertaking the development of a new drug that could make most types of cancers responsive to immunotherapy, including neuroblastoma, the most common cancer in infants, and breast cancer, the most common cancer in women. This could open a new line of treatment for those cancers and others.

Unlocking New Hope: Targeting METTL13 for the Treatment of Diffuse Midline Glioma

  • Principal investigators: Dr. Cynthia Hawkins, The Hospital for Sick Children
  • Project summary: Brain cancers are the leading cause of cancer-related deaths in children, and diffuse midline glioma (DMG) is one of its deadliest forms. This project is pursuing the development of a new drug or small molecule that can kill DMG cells by targeting a key enzyme involved in protein production. This therapy could improve the survival rates of children with DMG and may be effective in treating other types of cancer.

Late Accelerator

Generating an anti-BCMA trispecific natural killer engager for use in multiple myeloma

  • Principal investigators: Dr. Alissa Visram, The Ottawa Hospital and
    Dr. Scott McComb, National Research Council of Canada
  • Multiple myeloma (MM) is an incurable blood cancer and patients who do not respond to three frontline therapies (known as triple-refractory patients) typically live fewer than twelve months when treated with standard of care treatments. New immunotherapies in MM target the BCMA protein expressed on cancer cells, and lead to activation of T-cell immune subsets that kill cancer cells. However, these therapies are not widely accessible to patients in Canada. This project aims to develop a new form of BCMA therapy that will engage different kinds of immune cells (natural killer cells), that will be manufactured as an off-the-shelf product to avoid lengthy manufacturing delays that are associated with chimeric antigen receptor T (CAR-T) cell therapy. This study is the first step in creating cost-effective, accessible immunotherapies for Canadian patients with MM.

These four projects join CTIP’s portfolio of promising potential cancer therapeutics, which has now funded 30 projects to date. CTIP is supporting research in Ontario to move these therapies towards clinical use, while at the same time creating a pipeline of promising drugs to attract partnerships and investment to Ontario.

OICR is funded by the Government of Ontario. As the province’s cancer research institute, we take on the biggest challenges in cancer research and deliver real-world solutions to find cancer earlier and treat it more effectively. We are committed to helping people living with cancer, as well as future generations, live longer and healthier lives. For more information visit http://www.oicr.on.ca.

The views expressed are those of OICR and do not necessarily reflect the views of the Province of Ontario.

New training platform to help Canadian researchers gain data science skills

OICR’s Dr. Michelle Brazas will lead the initiative which has received $6 million in funding from CIHR and Genome Canada

Researchers face a tsunami of data and a growing set of powerful data analysis tools. Within these hide the potential for new breakthroughs in cancer research and other fields, but to get the most out of them researchers need up-to-date skills.

To drive the use of health and life science data in Canada for scientific discovery, the Canadian Institutes of Health Research (CIHR) and Genome Canada have awarded $6.05 million in funding over six years to establish the Canadian Bioinformatics, Computational Biology and Health Data Sciences Training and Community Platform.

OICR News chatted with Dr. Michelle Brazas, Associate Director of Adaptive Oncology at OICR and Scientific Director of the OICR-hosted Bioinformatics.ca, about the Platform, which she will lead in collaboration with colleagues across the country.

Can you tell us what the goals of the Platform are and why it is needed?

The goal of our Platform is to accelerate capacity building in bioinformatics, computational biology and health data sciences, with an emphasis on reaching audiences that haven’t been represented in these fields. The need to accelerate capacity building exists because in Canada, and globally, there is a skill gap between what researchers are taught in their formal education and what they need for their research work.

Universities and colleges provide an excellent and needed foundation, but as technologies change and people move into niche uses of data, they need additional skills. For example, in the context of cancer research, we are producing massive amounts of genomic and other ‘omics’ data, which in a way is the easy part. It is the analysis and interpretation that is hard, which is why we need to equip our researchers with data analysis skills so that they can leverage these new technologies to make discoveries which otherwise would not be possible.

How will the Platform achieve this?

Training alone will not get us to where we need to be, as learning continues beyond the classroom. So, with that in mind community support and mentorship is being given equal weight. We want to grow a national network of skilled researchers who know and support each other. We will be expanding our community activities and locations, providing programming that is both national and local, in regions throughout the country. To ensure that individuals from equity-deserving groups are benefitting from the Platform’s work, the concept of IDEA – inclusivity, diversity, equity, accessibility – will be central to what we do.

What will the training look like?

On the training side, we plan to bring together in a catalogue the training programs from key Canadian and international training providers to create a more cohesive strategy to deliver educational opportunities, instead of the piecemeal approach that has existed to date. Some of our training will be in-person, but we also know because of our pandemic experience with Bioinformatics.ca, that online training can be an effective mode of instruction as well. Researchers are already very busy, so we aim to provide short-format training opportunities in a variety of formats that deliver specifically what these researchers need.

We will also be offering training awards aimed at increasing the participation of individuals from equity-deserving groups, for example, Black and Indigenous researchers. We also plan to work at establishing partnerships with groups representing these communities so that we can co-develop training to serve their needs.

Can you tell us why mentorship is so important to the success of this initiative?

Mentorship is critical in a few different ways. Firstly, mentorship can help accelerate capacity building across the country, by guiding trainees on other professional and leadership skills relevant for their career development. Mentorship is also an important way to bring individuals from equity-deserving groups into the field and ensure they have the same opportunities to advance their careers. In time, trainees will become leaders in the community, so the mentorship cycle will also help set us up for long-term success.

What are the next steps for the Platform?

With funding from CIHR and Genome Canada in place, we are now working on putting our plan into action. Fortunately, we have a strong group of leaders from across Canada as well a strong foundation with Bioinformatics.ca, which will allow us to get the Platform up and running more quickly than if we were starting from scratch. We will have more to share with the community in a little while, but in the meantime, those who are interested in getting involved can get in touch with us at Bioinformatics.ca.

Dr. Michelle Brazas can be reached at support@bioinformatics.ca.  

Ask a Cancer Researcher: What is epigenetics?

Dr. Shraddha Pai, a Principal Investigator at OICR, explains what epigenetics is, its role in the formation of cancer and how epigenetics can be used to create new diagnostic tests and therapies for cancer.

Pharmacist and health policy specialist comes full circle as patient partner

Mona Sabharwal is the newest member of OICR’s Patient and Family Advisory Council.


Mona Sabharwal never had any doubt that patients have an important perspective to contribute to healthcare research and policy.

In fact, Sabharwal helped bring patient voices into Ontario’s drug-funding decisions when she worked in policy for the provincial Ministry of Health in the early 2000s – long before patient partnership was common practice.  

But it wasn’t until Sabharwal was diagnosed with acute myeloid leukemia in March 2023 and became a patient partner herself that she truly understood the patient perspective, and the vulnerability that comes with sharing it.

“When you’re asked to contribute to a research or policy initiative as a patient, you often don’t know the full context or the people involved, and you sometimes question whether they’re actually interested in what you have to say,” says Sabharwal, a pharmacist who is currently Senior Vice President at Rexall Pharmacy Group. “I look back at some of my interactions with patients when I was on the other side and wonder: is that how I made them feel?”

It’s that experience from both sides of patient partnership that drives Sabharwal. Though she says patient partnership has evolved immensely since the early 2000s, she believes patients can still do more to influence the care they receive.

Sabharwal joined OICR’s Patient and Family Advisory Council (PFAC) earlier this year. She recently spoke to OICR News about her experiences as a patient, pharmacist and policy expert, and how she hopes to apply them to improve cancer research.

How has your professional experience, as a pharmacist and in health policy, influenced your experience as a patient?

My experience and understanding of the healthcare system has empowered me to advocate for myself. When someone says ‘you can’t do that’ I have no problem asking why. I also know some of the levers within the health system, which has been helpful as I fight for my life against this disease. But I recognize that not everyone has this privilege, and that’s part of why I became a patient partner.

Has research played a role in your own experience with cancer?

I’ve been a participant in a few research projects as part of my cancer care. The experience has been positive overall – I think I benefitted from participating, and I hope others will benefit as well. But there were opportunities for improvement.

For example, one study tried to recruit me while I was very, very sick during treatment. I think most people would have declined in that situation. Then another study just stopped providing me with any updates once my participation was over. I received no feedback or follow-up information, even though my data became part of their dataset.

I’ve learned from these situations and look forward to applying that knowledge as part of OICR’s PFAC to help others have even more positive experiences.

What are your goals as a member of OICR’s PFAC?

I firmly believe that patients who participate in research are going to receive better care than if they didn’t. I believed that before I had cancer, and it has only been reinforced during my cancer journey. I would like to bring those advantages to light, and help more cancer patients access research.

I would also like to see patients play a bigger role in advocating for cancer research. It’s very compelling for policymakers and other decision makers to hear from the people who receive and benefit from research.

How has your experience with PFAC been so far?

OICR is leaps and bounds over many organizations that work with patients. Having staff members dedicated to patient partnership, as OICR does, is a huge step forward and really demonstrates the Institute’s commitment.

At the same time, I think there’s more that can be done. I’d like to see OICR continue to lead and continue to be bolder. Why not push the envelope a little more on how patients and family members can influence the health system?

No tumour sample, no problem: Blood test predicts immunotherapy outcomes without biopsy

Researchers from OICR and UHN have developed a predictive test that measures fragments of tumour DNA in the bloodstream.

A blood test developed by OICR-supported researchers has shown the potential to predict how patients with various types of cancer will respond to immunotherapy without needing to take a tissue biopsy.

The test, recently described in Cancer Discovery, harnesses an innovative technique called ‘cell-free methylated DNA immunoprecipitation sequencing’ to detect tiny pieces of cancer DNA circulating in the bloodstream.

Blood tests for cancer and other ‘liquid biopsies’ have emerged as intriguing alternatives to traditional biopsies, which can be invasive, painful and sometimes impossible for patients, depending on the location of their tumour.

But many liquid biopsies still need a sample of tumour tissue for reference that must be taken with a biopsy. That’s what sets this new test apart.

“This is a groundbreaking study, and the results demonstrate the promise of what are called ‘tumour-naïve’ assays to help guide cancer treatment without the need for a tissue sample,” said Dr. Lillian Siu, Senior Scientist at Princess Margaret and one of the study’s senior authors.

Siu, OICR’s Director of Genomics Dr. Trevor Pugh, and a team of researchers from OICR and Princess Margaret Cancer Centre (University Health Network) found that the amount of these DNA fragments detectable before and after a patient was treated with pembrolizumab – a type of immunotherapy – was a good predictor of whether their cancer would progress after treatment and whether they would ultimately survive the disease.

“A tumour-naïve assay like this has the potential to stratify risk without relying on tissue samples, and that could mean faster time to diagnosis and initiation of treatment,” says Dr. Eric Stutheit-Zhao, Postdoctoral Researcher at Princess Margaret and co-first author of the study.

A total of 204 blood samples from 87 patients were tested in OICR’s Genomics lab as part of the study. Researchers found that a decrease in the amount of methylated DNA over the first six weeks of pembrolizumab treatment was linked to a 60 per cent lower risk of death and a 65 per cent lower risk of disease progression compared to the reference group.

“We observed that a decrease in methylated ctDNA was associated with better outcomes, including progression-free survival and overall survival,” said Dr. Enrique Sanz-Garcia, Clinician Investigator at Princess Margaret and the study’s other first author.

This study comes out of the INSPIRE clinical trial, a collaboration between OICR and Princess Margaret led by Siu.

Previous INSPIRE research has shown the connection between circulating tumour DNA and how head and neck, breast, ovarian and other solid tumours respond to pembrolizumab. Those prior studies relied on a tumour-informed approach that required DNA sequencing of tumour samples to guide design of the cell-free DNA test.

This new work and other studies have generated a lot of excitement about blood tests and their potential to detect and diagnose cancer more accurately and with less burden on patients. Pugh also co-led a landmark study published last year where blood tests were used to detect cancer months earlier than imaging in patients with a rare form of hereditary cancer syndrome, and OICR has made liquid biopsies a key part of its research strategy.

“Liquid biopsies have the potential to change how we screen for cancer and monitor the progress and cancer treatment,” says Pugh. “And assays like this, which don’t require a reference tumour sample, could help unlock that full potential.”

This work was supported by OICR, the Princess Margaret Cancer Foundation, the Terry Fox Research Institute, the Princess Margaret Cancer Centre Global Oncology Program, the Cancer Research Institute, and Merck.