The Next Generation: Dr. Michael Taylor
Michael Taylor wants to find a novel treatment for the leading cause of death in pediatric cancer in Canada; one that won’t harm the developing brain of his young patients, lead to secondary cancers or prevent them from being able to hold a full-time job when they grow up. In his lab at The Hospital for Sick Children (SickKids), Taylor uses experience gained from 15 years of clinical and scientific post-secondary education and 24 years of biomedical research to help in his quest to increase the quality of life and survival of children with brain tumours (medulloblastomas).
An epiphany and a chance rotation in medical school led Taylor to his current position as a practicing neurosurgeon at SickKids. “In a graduate night-course in medical school, a professor showed slides demonstrating that cancer was caused by mutations in genes,” says Taylor. “This was 20 years ago and that idea was just starting to be very well accepted as a route for therapy.” Taylor was drawn to this fascinating concept and had a moment of revelation that the field of cancer might dramatically change during his lifetime. Later, in a rotation during a summer post as a medical student at Mississauga General Hospital, Taylor was asked to assist in neurosurgery. “I saw the doctors open a patient’s skull to access his brain and it was the most fascinating thing I ever saw,” says Taylor.
Taylor completed medical school at the University of Western Ontario, followed by a neurosurgery residency and a PhD at the University of Toronto. He moved on to St. Jude Children’s Research Hospital in Memphis, Tennessee, where he completed a clinical fellowship in pediatric neurosurgery and pediatric neuro-oncological surgery. He completed his first postdoctoral fellowship on the genomics of brain tumours, started a practice and completed a second postdoctoral fellowship in functional genomics.
The focus of Taylor’s research is to gain a better understanding of pediatric brain tumours, to eventually improve its therapy. “Leukemias and other non-solid cancers are very common but we have very good treatments for those and many of these children are successfully treated,” says Taylor. “However, many children still pass away from brain cancer and those who don’t are often left very disabled as a result of both the disease and treatment.”
Taylor receives a grant through OICR’s Cancer Stem Cell Program. It helps to fund research to determine how brain cancer spreads. “When children have brain cancer, it doesn’t spread through the blood or lymphatic system like adult cancer,” says Taylor. “It spreads instead by breaking off into the spinal fluid that bathes the brain and spinal cord, coating the brain and the spinal cord as it floats around and cuts off its blood supply.” Taylor explains that craniospinal radiation is one of the therapies used to treat these types of cancer but is harmful to the developing brains of children. Along with his colleagues, he hopes to find a therapy to treat cancers in children that increases the cure rate and decreases the complications of surgery.
One of the challenges to Taylor’s research is tumour heterogeneity. Two tumours might appear the same under the microscope, but can be very different molecularly. “Inter-tumour heterogeneity is very important because it can predict the clinical behaviour of tumours that look similar but are molecularly different,” says Taylor. “We can use protein and RNA biomarkers to determine the subgroup of a particular brain cancer and predict its response and outcomes to therapy.”
“To bypass the issue of heterogeneity, the solution is to study large numbers of tumours,” says Taylor. This is easier said than done. Taylor, passionate about his research and in need of samples, decided to form MAGIC (Medulloblastoma Advanced Genomics International Consortium). He personally contacted researchers worldwide to contribute samples to his laboratory. They answered his appeal and have contributed more than 1,200 frozen medulloblastoma tumours to his laboratory’s tumour bank.
Along with Drs. David Malkin and Marco Marra, Taylor is participating in a Genome Canada-funded study to analyze the genomes of pediatric medulloblastoma samples. RNA and microRNA expression profiles of 1,000 samples will be studied to identify novel subgroups. These expression profiles will be used to develop biomarkers to more reliably and accurately classify medulloblastomas. This project is now OICR’s third International Cancer Genome Consortium project and has received $10 million over three years from Genome Canada. Taylor also recently commenced a project with Dr. Rima Al-awar, which will screen high-risk medulloblastoma to find new treatments.
“Genetics is exploding with all the advances in next-generation sequencing,” says Taylor. “We will have a much better understanding of the genome of pediatric brain cancer in the next three to five years and will have identified targets for drugs.” The next step is to develop drugs that will work on the identified targets.
Taylor thinks OICR is well equipped to quickly translate his lab’s findings, making it easier to move into the translational phase where a drug is discovered and tested. “If our lab makes a target discovery, we can pass it on to OICR to take it one step further and get it closer to the bedside,” says Taylor. “I would like to get a drug into the clinic for patients that would allow us to use fewer of the current therapies, which can be very toxic.” Taylor hopes his research will provide a better quality of life for young brain cancer patients.
“If our lab makes a target discovery, we can pass it on to OICR to take it one step further and get it closer to the bedside.”
“Genetics is exploding with all the advances in next-generation sequencing. We will have a much better understanding of the genome of pediatric brain cancer in the next three to five years.”