Researchers from the Universities of Toronto and McMaster have just achieved promising results in trials of a new treatment for glioblastoma, a widespread and aggressive form of brain cancer.
Glioblastoma multiforme (GBM) is the most common brain tumor in adults. It is also the most aggressive. Although chemotherapy, radiation therapy, and surgery can be used to slow its progression, these measures have so far only had palliative value. Most patients have a life expectancy of less than one year, and only 3% of them reach the 5-year mark. Every year more than 241,000 people die from this terrible disease.
T-cells in use
T-cells play an important role in the immune response. Present in the blood, they are able to specifically target and destroy cells infected by a virus or a tumor. These diseased cells have mutated antigens that are different from those produced by healthy cells. Another type of immune cell (the antigen-presenting cell, APC) “warns” T-lymphocytes of these invaders through a structure called Major Histocompatibility Complex (MHC). As soon as presentations are made, the lymphocytes are able to recognize the unwanted antigens and destroy the cells that carry them.
However, cancer can interfere with this process in several ways, including reducing the availability of MHC. Therefore, one of the researchers’ strategies is to explore alternative ways of providing lymphocytes with the receptors needed to identify enemy cells. This is the role of the Chimeric Antigen Receptor (CAR), a molecule developed in the laboratory from patients’ lymphocytes. The lymphocytes are collected and then genetically modified to express a specific CAR receptor to the antigen produced by the cancer cells.
The treatment, developed by the team at McMaster University’s Singh Laboratory in collaboration with the University of Toronto’s Jason-Moffat Laboratory, specifically targets the CD133 protein found in glioblastoma cells. Tested in mice, it has shown promising results with reduced tumor load and improved life expectancy. These results have led to the establishment of a new company called Empirica Therapeutics, with the aim of carrying out the first clinical trials for this treatment and several others in 2022.
“We hope that our approach of targeting glioblastoma cells with CAR-T therapy will provide patients with a better quality of life and increased survival,” said Jason Moffat, Chief Scientific Officer of Empirica Therapeutics. Sheila Singh, a co-founder of the new company, added that the treatment opens up new avenues to identify and destroy particularly aggressive glioblastoma cell populations, a new step in the fight against this dreaded disease.