Published on
Updated
Reading 3 mins.
in collaboration with
Ivan Pourmir (medical oncologist)
Hijacking already cancerous cells to mutate them into anticancer agents reinjected into the tumor, this is one of the latest studies from the Harvard Medical School. A Trojan horse strategy that shows promising results against brain cancers.
Fight fire with fire. This is the image with which scientists at Harvard Medical School evoked their latest study aimed at finding a cure for glioblastoma, the most common brain cancer in adults. Why that ? Because their idea is based on an ingenious concept: using cancer cells and modifying them to make them cancer killers. “Our team followed a simple idea: take cancer cells and turn them into vaccines.”, explains the lead author of the research, Khalid Shah. Their work can be read in the journal Science Translational Medicine.
Reprogram living cancer cells into Trojan horses
The scientists relied on known methods of cell therapy. The team of scientists extracted living tumor cells. Called ThTCs, the cells have been modified by the CRISPR-Cas9 “genetic scissor” to give them the ability to produce high amounts of two small immune system proteins, with the aim of repurposing them as a tumor cell-killing agent . “Live tumor cells are like carrier pigeons. They have the particularity of traveling long distances through the brain but end up returning to their original home with the other tumor cells” explain the authors. Once back in their original home, these modified cells set out to kill other cancer cells. The team, however, had to invent a kind of isafety switch, which, when activated, allows the killer cell to self-destruct.
This cutting-edge work has another particularity: to prevent any return of the cancer, the researchers added a characteristic to the modified tumor cells so that they could be easily identified by the immune system, which memorized them. If the cancer comes back, the immune cells can quickly return to the places where the cancer cells are growing and fight them off.
A promising treatment in mice
Impossible to claim victory for all that. For now, the team of scientists has experimented with this technique on mice carrying glioblastoma, the most common and very aggressive form of brain cancer. At this stage, the scientists concluded that the animals had greater survival and long-term immunity to primary, recurrent and metastatic cancers. “This dual-action cell therapy was safe, applicable, and effective in these models, suggesting a roadmap for developing a therapy“they announce.
Even if these tests on animals are promising, we are still far from tests carried out on human subjects. However, the search is actively continuing to reach a viable solution: “Most patients with aggressive brain cancer do not survive beyond 15 to 18 months” recalls the first author of the study.
Can using “living” tumor cells make a difference?
Consulted about this study, Dr. Ivan Pourmir, oncologist specializing in immunotherapy and member of our committee of experts, recognizes an interesting approach, even if it is still too experimental to be considered on humans.
“Historically, it is known that deactivated cells can present antigens to the immune system, but this functioning is not sufficient. Using and modifying “living” tumor cells to release toxic products, attract immune cells and educate them to get rid of cancer is a promising avenue. It’s still experimental, but the concept is a good strategy.”
A particularly relevant strategy in research against glioblastoma, continues the researcher:
“Glioblastomas are tumors that deeply infiltrate the brain, difficult to remove surgically and extremely frequent recurrences. Harnessing the very biology of the tumor cell to make its way, colonize an inaccessible tumor and attract immune cells to the same location gives serious hope.”