Canadian researchers discover unsuspected early origins of childhood brain cancer
Study identifies the earliest traces of brain cancer long before the disease becomes symptomatic
Brain tumors are the leading cause of non-accidental death among children in Canada; however, little is known about when these tumors are formed or how they develop. Researchers have recently identified cells thought to be causing some brain tumors in children, and discovered that these cells first form in the embryonic stage of mammalian development - much earlier than they expected.
The findings of this study, published today in Nature, could pave the way for the discovery of better treatments to tackle these lethal brain tumors.
"Progress in developing more effective treatments for brain cancer is largely slowed by complex heterogeneity, that is, by the variety of cells in each tumor," says Dr. Michael Taylor. , one of the study's lead co-authors, who is a specialist in pediatric neurosurgery and a researcher in Developmental Biology and Stem Cells at the Hospital for Sick Children (SickKids). We recognized that new technologies could help us decipher some of this complex reality; We decided to team up with McGill University and the Ontario Institute for Cancer Research (OICR) to work together on this problem by sharing our expertise and experience. "
Using mouse models, the group of researchers studied the various types of normal brain cells and how they formed in the cerebellum - where brain tumors are most often seen in children, with various types of brain cells. stages of their development. The researchers mapped the lineages of more than 30 cell types and identified normal cells that would later become cancer cells, also known as cells of origin.
To identify these normal cells eventually turning into cancer cells, the researchers used single-cell sequencing technology, which allows them to study individual cells more precisely than traditional sequencing methods.
As part of their work, the researchers observed the original cells at a much earlier stage of fetal development than expected, Dr. Taylor, who is also a professor in the Department of Surgery, commented. , Laboratory Medicine and Pathology at the University of Toronto and Co-Director of the IORC's Institute for Translational Research in Brain Cancer.
"Our data show that in humans, brain tumors are in some cases cell populations or events dating back six weeks of intrauterine life," says Dr. Lincoln Stein, co-lead author of the study and head of the study. adaptive oncology program at IORC. These results suggest that brain tumors may develop well before they are clinically visible, or even before a woman knows she is pregnant. "
"The brain is remarkably complex. Our findings are not only important for understanding brain tumors, but they will also help us learn more about brain tumor cells and how they work, helping children with delayed brain tumors. neurodevelopmental. What we have achieved as a team in this paper is a source of hope for patients, "says Dr. Nada Jabado, co-lead author of the study, who is a pediatric hemato-oncologist at and a researcher at the heart of the study. the Child Health and Human Development Program of the Research Institute of the McGill University Health Center (RI-MUHC). Dr. Jabado is also a professor of pediatrics and human genetics at McGill University.
With this new knowledge, researchers can now study the differences between the development of healthy normal cells and that of cells that will eventually give rise to cancer cells.
