Jean-François Côté and Islam Elkholi
Credit: IRCM
Canadian scientists have identified a promising therapeutic target to attack to prevent breast cancer from recurring: the protein PIK3C3.
Published this month in Cancer Research, the findings by a team led by Université de Montréal medical professor Jean-François Côté reveal that PI3KC3 is essential for the survival of dormant cancer cells.
By targeting this protein, scientists led by Côté at the UdeM-affiliated Montreal Clinical Research Institute (IRCM), where he runs the cytoskeletal organization and cell migration research unit, were able to eliminate the dormant cells before they triggered a metastatic relapse.
"Metastasis remains one of the greatest challenges for patients living with breast cancer," said Côté. "Understanding how to prevent this process is key to improving their rate of survival."
Islam Elkholi, an ocologist with a PhD in molecular biology from UdeM who's now a postdoctoral fellow at McGill University, is the study's first author.
"Pinpointing factors that allow cancer cells to survive during the dormancy phase, such as PIK3C3, would guide emerging clinical trials that investigate therapeutic opportunities for breast-cancer patients at risk of developing metastatic relapses," Dr. Elkholi said.
The study was done in collaboration with colleagues at McGill, the University of Toronto, as well as the Albert Einstein College of Medicine, Lee Moffitt Cancer Center & Research Institute, and Fred Hutchinson Cancer Center, in the United States.
Breast cancer is among the most common forms of cancer and is the second leading cause of cancer death among Canadian women.
Approximately one in four breast cancer patients experience metastatic recurrence, months or even years after their initial diagnosis and treatment. These recurrences occur when cancer cells spread from the breast to distant organs, where they remain dormant before reactivating.
About this study
"Targeting the Dependence on PIK3C3-mTORC1 Signaling in Dormancy-Prone Breast Cancer Cells Blunts Metastasis Initiation," by Jean François Côté et al., was published May 15, 2025 in Cancer Research. Funding was provided by the Cancer Research Society (Canada), the Canadian Institutes of Health Research, the Canada Research Chair program, and the U.S. National Institutes of Health/National Cancer Institute, as well as by philanthropic support from the IRCM Foundation including the Transat Breast Cancer Research Chair and the Alain Fontaine Chair in Cancer Research.
