A cancer treatment that stimulates the immune system and which has been successfully tested in mice will soon be the subject of clinical trials in humans.
Will we soon be able to cure cancer with a simple injection? This is the hope of a discovery made by researchers at Stanford University in the United States.
Their study, published in late January in the journal Science Translational Medicine showed that the injection of two immunostimulatory agents directly into the tumor can be used to target and destroy cancer cells. This combined treatment causes an immune response and can be easily administered by injection, hence the qualification of it by scientists of “vaccine” against cancer, even if it is technically not one. Until now tested on mice, it will soon be the subject of clinical trials on humans.
A treatment that reactivates immune cells
The “vaccine” developed by the researchers consists of two types of safe “immunostimulatory agents”. The first, an antibody called anti-OX40, activates CD4 T cells, auxiliary cells that communicate with other immune cells. It also activates the “killer” CD8 cells that release chemicals that destroy the malignant cells. The other vaccine agent is a short strand of synthetic DNA that allows the immune cells to produce a surface protein called TLR9 ligand. This protein in turn stimulates the production of antibodies that leads to the creation of specialized memory cells. This will recognize the malignant cells if they reappear in the future.
“Immune cells like T cells recognize the abnormal proteins that are often found in cancer cells and infiltrate them to attack the tumor,” says the Stanford Medicine Magazine, “but as the tumor develops, it often finds ways to suppress the activity the T cells. The method developed by Dr. Levy works to reactivate cancer-specific T cells by injecting microgram quantities of two agents directly into the tumor site. ”
An efficiency rate of 97%
Injected into solid tumors of mice, the vaccine activated the immune system in a localized way, targeting cancer cells and leaving healthy cells intact. The vaccine not only eliminated 97% of mouse lymphomas, but also eliminated secondary malignancies resulting from the original cancerous tumors. In addition, say the researchers, this treatment would be effective against several types of cancer.
“When we use these two agents together, we see the elimination of tumors all over the body. This approach bypasses the need to identify tumor-specific immune targets and doesn’t require wholesale activation of the immune system or customization of a patient’s immune cells,” says Dr. Ronald Levy, professor of oncology and lead author of the study in an interview with Stanford Medicine Magazine.
An alternative to chemotherapy?
Researchers now want to test the efficacy of the treatment in humans with a subtype of low-grade non-Hodgkin’s lymphoma called B-cell lymphoma. They hope is to recruit a total of 35 adult patients to form two study groups by the end of the year. The purpose of the test will be to determine the optimal dose of the treatment and to examine the side effects.
“All of these immunotherapy advances are changing medical practice,” says Dr. Levy in the interview. Indeed, if it proves effective this vaccine can soon be used as a rapid and effective cancer therapy without subjecting patients to chemotherapy.