Recent News
A New Class of RNA Therapies
RNA-based approach shows potential for treating genetic diseases like cystic fibrosis.
Read MoreA New Class of RNA Therapies
RNA-based approach shows potential for treating genetic diseases like cystic fibrosis.
Approximately 11% of genetic disorders are caused by mutations that prematurely halt messages encoded in DNA. One such condition is cystic fibrosis, a genetic disorder that can result from mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. In a new study published in Science, researchers at UHN’s Princess Margaret Cancer Centre (PM) developed an RNA-based therapeutic strategy to treat diseases caused by these mutations and successfully corrected a premature CFTR stop mutation in laboratory models.
When DNA is copied into messenger RNA (mRNA), the mRNA is then used as a template to make proteins that carry out the body's functions. Some DNA mutations can create a premature ‘stop’ signal, causing the cell to stop producing a protein too soon, which can contribute to disease. This faulty ‘stop’ signal is called a premature termination codon (PTC).
Therapeutic approaches have been developed to overcome PTCs through engineered molecules known as suppressor transfer RNAs (sup-tRNAs), which can bypass these faulty stop signals and enable the production of full-length, functional proteins. However, engineering safe and effective sup-tRNAs, delivering them efficiently to target cells, and achieving sufficient activity in living cells remain major challenges.
To address these challenges, a team co-led by Dr. Bowen Li, Affiliate Scientist at PM, tested chemical modifications of sup-tRNAs. They identified a modification that increased sup-tRNA stability and efficiency, improved protein production, and reduced unwanted immune system responses.
The researchers also improved delivery of sup-tRNAs to cells by developing a lipid nanoparticle (LNP)—small, lipid-based delivery vehicles that safely carry genetic medicines into cells—specifically tailored to carry sup-tRNAs. Analysis revealed that these LNPs efficiently delivered sup-tRNAs to lung tissue via inhalation.
Cystic fibrosis is a hereditary condition that causes progressive lung damage. Approximately ten percent of patients have mutations that cause a premature ‘stop’ signal and cannot benefit from current therapeutics. The team tested their approach in cystic fibrosis laboratory models and patient-derived tissue samples carrying these mutations and successfully restored the CFTR protein function.
Researchers say the findings could pave the way for a new platform of genetic medicines capable of treating a wide range of diseases caused by mutations that lead to these premature stop signals.
Doctoral Candidate Jingan Chen and Postdoctoral Researchers Dr. Muye Zhou and Dr. Songtao Dong are co-first authors of the study in Dr. Bowen Li’s lab.
Dr. Bowen Li, Affiliate Scientist at UHN’s Princess Margaret Cancer Centre and Associate Professor at the Leslie Dan Faculty of Pharmacy at the University of Toronto, is a co-corresponding author of the study.
Dr. Haissi Cui, Assistant Professor in the Department of Chemistry at the University of Toronto, is a co-corresponding author of the study.
This work was supported by the Leslie Dan Faculty of Pharmacy, the Connaught Fund, the Canadian Institutes of Health Research, the Natural Sciences and Engineering Research Council of Canada, Cystic Fibrosis Canada, Harrington Discovery Institute, the National Institutes of Health, the Government of Canada, Cystic Fibrosis Foundation, PRiME, Next Generation Precision Medicine initiative, and The Princess Margaret Cancer Foundation.
Dr. Li is a Tier 2 Canada Research Chair in RNA Vaccines and Therapeutics and the GSK Chair in Pharmaceutics and Drug Delivery.
Jingan Chen, Dr. Haissi Cui, and Dr. Bowen Li are inventors on an invention disclosure that covers compositions, methods, and uses of the engineered/modified sup-tRNAs. Jingan Chen, Dr. Muye Zhou, Dr. Songtao Dong, and Dr. Bowen Li are inventors on an invention disclosure that covers the described ionizable lipids.
Chen J, Zhou M, Dong S, Gong F, Tennakoon R, Seto BY, Chen ZR, Zhou ZP, Pan J, Xu Y, Luozhong S, Macarios CM, Tijaro-Bulla S, Gonska T, Hu J, Cui H, Li B. Nonviral delivery of chemically modified tRNA rescues nonsense mutations in cystic fibrosis. Science. 2026 Aug 27;393(6814):eaeb0054. doi: 10.1126/science.aeb0054.
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Navigating Uncertainty in ALS
Exploring how people with ALS make care decisions amid uncertainty about symptom progression.
Read MoreNavigating Uncertainty in ALS
Exploring how people with ALS make care decisions amid uncertainty about symptom progression.
Image Caption: Amyotrophic lateral sclerosis (ALS) is a fast-progressing neurological disease that affects movement and brain function. As symptoms change over time, patients and families often face complex decisions about managing care and maintaining quality of life.
For people living with amyotrophic lateral sclerosis (ALS), everyday activities such as speaking, eating, and swallowing can become increasingly difficult as the disease progresses. Researchers from UHN’s KITE Research Institute, Sunnybrook Health Sciences Centre, and the University of Toronto found that uncertainty about ALS progression can make it challenging for patients to decide when and how to manage their symptoms, highlighting the need for better support and communication from health care providers.
ALS is a progressive disease, and over time, many patients develop bulbar symptoms, which affect speech and swallowing functions. These symptoms are associated with reduced quality of life and can worsen rapidly once they appear. Therefore, early and timely intervention, such as communication aids, dietary changes, or feeding tubes, may help patients maintain function and independence. However, the unpredictable nature of ALS can make it difficult for patients to know when to act.
To better understand these challenges, the research team interviewed 12 adults with ALS, including people with and without bulbar symptoms. Using in-depth interview techniques, the researchers explored how patients approached decisions about symptom management and what support they wanted from health care professionals.
After analyzing participant responses, three key themes emerged: disease uncertainty; quality of information; and personal values and beliefs. Uncertainty about when symptoms might appear or worsen often delayed discussions about treatment options. Some participants preferred to wait until symptoms developed, while others wanted to learn about future options early to plan ahead. Participants also emphasized the importance of receiving clear, personalized information tailored to their individual circumstances, including how symptoms might progress and when interventions should be considered. This helped patients feel more prepared to make decisions. Finally, personal values and beliefs played a key role in decision-making. Priorities included maintaining quality of life, preserving independence, supporting family relationships, and reducing burdens on loved ones, which often influenced decisions.
The findings highlight the need for more person- and family-centered ALS care. Providing timely individualized information and incorporating patients’ values and family perspectives may help patients navigate the complex care decisions that come with living with ALS.
Anna Huynh, first and corresponding author of the study, is a PhD Candidate at the Rehabilitation Sciences Institute at the University of Toronto in the lab of Dr. Yana Yunusova.
Dr. Yana Yunusova, senior author of the study, is a Senior Scientist at UHN’s KITE Research Institute and the Sunnybrook Research Institute. Dr. Yunusova is also a Professor in the Department of Speech-Language Pathology and Director of the Rehabilitation Sciences Institute at the University of Toronto.
This work was supported by the National Institutes of Health, KITE-Toronto Rehabilitation Institute, Fondation Vincent Bourque, ALS Canada, and Brain Canada. Operational support for the KITE Research Institute was provided by UHN Foundation.
The research team is grateful to the research participants—patients living with ALS—as well as ALS neurology partners, Drs. Lorne Zinman and Agessandro Abrahao.
Huynh A, Cranley L, Barnett-Tapia C, Abrahao A, Zinman L, Yunusova Y. Understanding patients' experiences and needs around decision-making for bulbar symptom management at a multidisciplinary ALS clinic. Disabil Rehabil. 2026 Jul 1. doi: 10.1080/09638288.2026.2693395.
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Shaping Canadian Health Sciences
Four UHN researchers elected as Fellows of the Canadian Academy of Health Sciences.
Read MoreShaping Canadian Health Sciences
Four UHN researchers elected as Fellows of the Canadian Academy of Health Sciences.
Image Caption: (Pictured clockwise from the top left) Drs. Niall Ferguson, Jennie Johnston, Gang Zheng, and Michael Milosevic.
Four UHN researchers were elected as Fellows of the Canadian Academy of Health Sciences (CAHS)—one of the highest honours in Canadian health sciences. Fellows are nominated from diverse disciplines and recognized for excellence in advancing academic research and improving health and health systems in Canada.
Congratulations to the following UHN researchers, who were among the 59 newly elected Fellows:
● Dr. Niall Ferguson is a Senior Scientist at UHN’s Lung and Respiratory Research Institute. His research focuses on improving outcomes for patients with acute respiratory failure, largely through clinical trials of mechanical ventilation and extracorporeal life support strategies, which temporarily support blood oxygenation outside the body.
● Dr. Jennie Johnstone is a Clinician Investigator at UHN’s Organ Systems and Integrated Health Sciences Research Institute. Her primary area of research is the prevention of hospital-acquired infections.
● Dr. Michael Milosevic is a Clinician Scientist at UHN’s Princess Margaret Cancer Centre. His research examines how advanced, image-guided radiotherapy and biological targeting of hypoxia (low oxygen levels within tumours) and the tumour microenvironment can improve outcomes for patients with gynecologic cancers.
● Dr. Gang Zheng is a Senior Scientist and Associate Research Director at UHN’s Princess Margaret Cancer Centre. Working in the field of cancer nanomedicine, his research develops innovative imaging, diagnostic, and targeted treatment technologies to advance precision cancer care.
For a full list of the 2026 CAHS Fellows, read the press release here.
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Improving Gene Editing Efficiency
New AI method can predict the performance of CRISPR gene editing tools.
Read MoreImproving Gene Editing Efficiency
New AI method can predict the performance of CRISPR gene editing tools.
Image Caption: CRISPR-Cas9 is a gene-editing tool that enables scientists to modify DNA. The system works by using a short piece of RNA to acts as the guide, directing the Cas9 enzyme to a specific spot where it can cut the DNA.
A study from UHN’s Princess Margaret Cancer Centre (PM) introduces a new AI model that can help scientists design more efficient gene editing tools.
Gene editing enables scientists to make targeted changes to DNA in living cells. These approaches are widely used in biomedical research and have potential applications in treating disease, including correcting disease-causing mutations, identifying potential drug targets, and investigating gene function.
The CRISPR-Cas 9 system is one of the most widely used gene editing tools and uses a short piece of RNA, known as single-guide RNA (sgRNA), to direct the Cas9 protein to a specific location in the genome, where it can cut DNA. However, not all sgRNAs perform equally well, and predicting which guides will be most effective remains a challenge.
As the sequence of the sgRNA affects its gene editing performance, careful guide design is essential. Several AI models have been developed to help predict which RNA sequences will work best. However, these programs often function as "black boxes”, providing little information about how the models work. They also often overlook how the position of patterns within sgRNA sequences influences their effects on Cas9.
To address this problem, the team, co-led by Dr. Sushant Kumar, Scientist at PM, and collaborators developed DeepCC9, a new machine learning framework designed to be both accurate and interpretable. The model identifies position-based sequence patterns for sgRNAs that affect gene editing efficiency. DeepCC9 enables users to learn what sequence features drive this predictive performance.
When tested using datasets for different Cas9 variants, DeepCC9 outperformed existing approaches in predicting how well gene editing would perform. In addition, the researchers identified 74 informative features of sgRNA sequences associated with the prediction of Cas9 genome-editing efficiency. They also found that the position of these features within an sgRNA can significantly affect how well Cas9 binds to and cuts DNA.
These findings provide a clearer picture of the sequence features that contribute to successful gene editing and could help scientists design more effective sgRNAs for research and biotechnology applications. DeepCC9 may help accelerate discoveries in genome engineering and other areas of molecular biology.
Nasim Bakhtiyari, doctoral candidate at Tabriz University of Medical Sciences, is the first author of the study.
Dr. Yosef Masoudi-Sobhanzadeh, from the Department of Computer Engineering, Istanbul Rumeli University and the Department of Molecular Medicine, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, is a co-corresponding author of the study. He was a Postdoctoral Researcher at UHN’s Princess Margaret Cancer Centre at the time of this study.
Dr. Safar Farajnia, Professor of Biotechnology, Drug Applied Research Center & Biotechnology Research center, Tabriz University of Medical Sciences, is a co-corresponding author of the study.
Dr. Sushant Kumar, Scientist at UHN’s Princess Margaret Cancer Centre and Assistant Professor in the Department of Medical Biophysics at the University of Toronto, is the co-corresponding author of the study.
This work was supported by the Princess Margaret Cancer Foundation, the Terry Fox Research Institute, the Drug Applied Research Center, and Tabriz University of Medical Sciences.
Dr. Sushant Kumar is a Tier 2 Canada Research Chair in Genomic Medicine.
Bakhtiyari N, Masoudi-Sobhanzadeh Y, Farajnia S, Kumar S. An interpretable deep learning framework uncovers features governing CRISPR-Cas9 genome-editing efficiency. Bioinformatics. 2026 Jul 2;42(7):btag483. doi: 10.1093/bioinformatics/btag483.
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Celebrating Transplant Research
UHN’s Ajmera Transplant Centre Research Day was a showcase of discovery and collaboration.
Read MoreCelebrating Transplant Research
UHN’s Ajmera Transplant Centre Research Day was a showcase of discovery and collaboration.
Image Caption: Moments from Ajmera Transplant Centre Research Day, featuring scientific sessions, participant engagement, and award recipients.
UHN’s Ajmera Transplant Centre (ATC) brought the transplant community together for its annual Research Day, an energizing forum that spotlighted the ideas, collaborations, and people driving progress in solid-organ transplantation.
Close to 200 clinicians, scientists, trainees, patient partners, and health professionals filled the Transplant Innovation Centre for a day designed to spark discussion and accelerate discovery. The program featured four scientific sessions: New Horizons in Transplantation, Innovations in Transplantation, Nursing, Health Disciplines and Quality Improvement, and Clinical Research at Ajmera Transplant Centre.
The day featured an exciting lineup of speakers, including keynote presenter Dr. Alireza Rabi, cardiac surgeon and Affiliate Scientist at UHN's Peter Munk Cardiac Centre, who shared how innovation in donor heart recovery, preservation, and repair can expand access to heart transplantation. Four invited experts and six recipients of Ajmera grants and fellowships also presented emerging findings that point to new opportunities for impact.
The breadth and depth of transplant research at UHN were on full display through 39 electronic posters and 39 printed posters. Judges recognized Sarayna Bala and Dr. Naga Karthik Enamundram in the Basic/Translational Science category, and Dr. Emmanuel Lafont and Dayana Davoudi in the Clinical Science category.
The event also celebrated the people whose contributions are advancing research, teaching, mentorship, and patient care across the transplant community. Among the award recipients were Dr. Ana Konvalinka and Dr. Juan Montagne, who received the Dr. Gary Levy Award for Excellence in Clinical and Translational Research.
Additional honours recognized excellence in teaching, mentorship, citizenship, and clinical education across faculty, fellows, and health professionals. Dr. Cynthia Tsien and Dr. Melinda Nguyen received the Dr. Paul Greig Award for Excellence in Teaching. The Dr. Heather Ross Award for Exemplary Citizenship and Mentorship in Transplant was awarded to Dr. Vivek Rao and Dr. Mukesh Kumar. Alicia Healey received the Nursing and Health Professions Excellence in Clinical Teaching Award.
Together, the day captured the spirit of ATC: bold science, strong partnerships, and a shared commitment to improving outcomes and quality of life for transplant patients. It also underscored ATC’s leadership in shaping the future of transplant research, education, and care.
The Ajmera Transplant Centre Research Day 2026 was made possible through the generous support of sponsors Astellas, Merck, and Takeda as Gold Sponsors, and Traferox as Silver Sponsor.
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Celebrating Youth Contributions
UHN supports youth in STEM as they pursue their aspirations and share unique perspectives.
Read MoreCelebrating Youth Contributions
UHN supports youth in STEM as they pursue their aspirations and share unique perspectives.
Image Caption: 2026 UHN STEM Pathways youth in action.
In honour of International Youth Day, we are highlighting how four UHN summer students are contributing to the future of research and health care.
At UHN, investing in the next generation is more than a commitment; it is an important part of advancing research. Through the UHN STEM Pathways summer research program, 37 high school students had the opportunity to gain hands-on experience working alongside researchers, clinicians, and research staff while exploring various research fields and developing the skills and confidence to support their future STEM (science, technology, engineering, and mathematics) aspirations. This summer program seeks to support students who experience socioeconomic disadvantages, systemic racism, and barriers to participation in STEM.
This year’s International Youth Day theme, Different Contexts, Common Aspirations, recognizes how today's youth often share common goals for the future despite being shaped by diverse experiences. Learn about the unique experiences of four UHN summer research students and discover the aspirations driving their work.
Yusrah Surajudeen | Summer Research Student in the lab of Dr. Jason Fish
My interest in STEM began with psychology and a curiosity about how thoughts, emotions, and behaviours work. Through UHN STEM Pathways, I had the opportunity to join the lab of Dr. Jason Fish at UHN’s Peter Munk Cardiac Centre. Here, I worked on a project focused on activating a KRAS genetic mutation in an advanced preclinical model using blue light.
Working alongside scientists at UHN showed me what research is like beyond the classroom. This experience taught me the importance of patience, problem-solving, and attention to detail. Research does not always go as planned, but every challenge is an opportunity to learn and ask questions.
In the future, my aspiration is to become a clinical researcher who combines both patient care and scientific discovery. Being at UHN has reinforced my ambitions by showing me how discoveries can make an impact.
My advice for future summer research students is to take advantage of every opportunity, whether it is attending the tours or presentations or introducing yourself to those around you. Everyone has a unique story and valuable advice to share. These experiences helped me understand many different career paths in research and made my placement much more rewarding than I expected.
Illia Lysenko | Summer Research Student in the lab of Dr. Ralph DaCosta
My passion for STEM started with learning about the immune system and how our bodies protect us. Through UHN STEM Pathways, I had the opportunity to be a summer research student in Dr. Ralph DaCosta’s lab at UHN’s Princess Margaret Cancer Centre. I participated in literature reviews and cell culture work, while contributing to projects involving pancreatic cancer cell research. My experience at UHN has taught me that innovation starts with creative problem-solving and requires finding new ways to make research more efficient and effective.
My STEM aspiration is to pursue a career as a nursing researcher. My time at UHN has helped me better understand how research and patient care work closely together to improve lives. If you are interested in STEM, my advice is to ask a lot of questions, take advantage of every opportunity, and understand that mistakes can happen, but to take them as part of the learning experience.
Selena Medrano | Summer Research Student in the lab of Dr. Catriona Steele
Throughout my life, I have always been fascinated by the human body and inspired by family members working in health care. This summer, in the Swallowing Rehabilitation Research lab at UHN’s KITE Research Institute, I supported research activities ranging from analyzing resources for chronic lung disease to knowledge translation projects and clinical X-ray observations.
What stood out most about my experience was the opportunity to learn from a variety of experts across UHN. Through STEM Pathways’ hospital tours, shadowing experiences, and conversations with researchers, I gained valuable insights, including the importance of paying attention to detail and communicating effectively with team members.
Despite being in a new environment, I felt supported by passionate people who genuinely wanted to support my learning and growth. Their encouragement gave me confidence to step out of my comfort zone, making this experience positive and rewarding. Seeing how UHN research advances patient care motivates me to contribute to meaningful work and strengthens my aspiration to pursue a career in radiology.
My advice to future youth in STEM is to make the most of every opportunity, seek feedback, and take initiative when you can. The skills you develop and the connections you make are just as valuable as the experience you gain from the work itself.
Adam Ali | Summer Research Student at UHN's Department of Research Analytics
My interest in STEM grew through hands-on experiences at school that gave me insight into a variety of careers and ultimately helped me discover my interest in biomedical engineering. This summer, I joined UHN’s Department of Research Analytics, where I worked with large research datasets and explored integrating artificial intelligence to improve team workflows.
This opportunity has expanded my understanding of research and data analysis, while helping me develop practical skills that will support my academic and professional goals in STEM. I have learned that working with artificial intelligence requires patience and problem-solving because finding effective solutions often involves trial and error.
These experiences at UHN reinforced my aspiration to develop innovative and accessible scientific technologies that can improve patient outcomes around the world. My advice for future students is to stay curious, be open to new experiences, and not be afraid to ask for help.
The experiences of Yusrah, Illia, Selena, and Adam highlight the impact of providing the next generation with meaningful opportunities to learn, contribute, and grow. Through programs like STEM Pathways, UHN is helping students explore career opportunities in STEM, build confidence, and gain a strong foundation in research and health care.
Meet the next generation of STEM leaders as the STEM Pathways summer research students share their aspirations for the future.
UHN STEM Pathways is a Toronto-based outreach program that aims to inspire and educate students from kindergarten to grade 12 through interactive tours, scientist panels, hands-on workshops, and classroom visits. For more information on their current offerings, click here or contact stempathways@uhn.ca.
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Research Spotlight
Read the latest bi-monthly newsletter that highlights advancements from UHN researchers.
Read MoreResearch Spotlight
Read the latest bi-monthly newsletter that highlights advancements from UHN researchers.
Welcome to the latest issue of Research Spotlight.
As Canada’s largest research hospital, UHN is a national and international source for discovery, education, and patient care. This newsletter highlights top research advancements from over 5,000 members of TeamUHN—a diverse group of trainees, staff, and principal investigators who conduct research at UHN.
Stories in this month’s issue:
● Hearing, Balance, and Thinking: Cognitive training improves balance and multitasking with varied benefits to hearing ability.
● Guiding Equal Heart Failure Care: Study finds new strategy for heart failure care is equally effective for males and females.
● Brain Stimulation to Treat OCD: Large-scale UHN-led study finds brain stimulation treatments may help people with severe OCD
● New Clues to Leukemia Relapse: Researchers uncover how DNA elements may fuel leukemia recurrence and therapy resistance.
Read these stories and more online here. To read previous issues, see the newsletter archive.
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Research Institutes at UHN
Research conducted at UHN's research institutes spans the full spectrum of diseases and disciplines, including cancer, cardiovascular sciences, transplantation, neural and sensory sciences, musculoskeletal health, rehabilitation sciences, and community and population health.
Research Institutes
Research at UHN is conducted under the umbrella of the following research institutes. Click below to learn more:
