Scientists discover double substances that activate the immune system and put the body’s defense cells to fight the tumor – no matter what part of the body it appears
A tumor is made up of mutant cells, with modified genetic code. These cells produce different proteins, which, as an alarm, catch the attention of our immune system. White blood cells, the cops of our body, are sent to the scene of the crime, guided by these proteins. Their function is to destroy the cancer, but when they get there, they are paralyzed and can not react – the tumor has biochemical tricks on its sleeve to save itself.
Radiotherapy and chemotherapy are valuable treatments. But it would be much easier to “wake up” the white blood cells – and let them take care of the tumor with their bare hands.
This trick is about to come off the paper. Researchers at Stanford University have discovered two agents that, when injected directly into a tumor, make the patient’s defense cells that were already there resume combat. The technique, which completely eliminated cancer in 87 of the 90 laboratory mice tested, has the advantage of also combating metastases – “branches” of the original tumor that form in other parts of the body.
Treatments for cancer that activate the immune system are called immunotherapies, and several of them are already applied in hospitals. One of the newly developed modalities involves removing white blood cells from the patient, using genetic engineering to edit them in the laboratory and then injecting them back into the body. Agreed. Another involves activating the entire immune system, not just the cells in the region where the tumor is located – which can cause side effects. None of them is as straightforward as the new solution.
“All of these advances in immunotherapy are changing medical practice,” said Ronald Levy , a professor of oncology and lead author of the study, published in Science . “But our approach does not require the complete activation of the immune system nor the customization of the patient’s immune cells. We apply very small amounts of two agents only once, and they only stimulate the defense cells that are already inside the tumor [ attracted by their proteins ]. “
The agents in question are a bit of DNA called an oligonucleotide and an antibody – which is, in a simplified way, a protein that tells the immune system that there is an enemy to fight. Together, the two nudge a receptor called OX40, which sits on the defense cell membrane. It’s like a button: when it’s tight, the lymphocyte goes up.
The active cell is obstinate: once it devours the main tumor, it detects the secondary tumors that have spread to other parts of the body. She runs back and kills them as well – after all, she already knows what the biochemical signature of mutant cells is.
The first test was done on 90 rats with lymphoma (cancer of the lymphatic system). 87 of them were healed on the first try, the remaining three on the second. Animals with melanoma, breast cancer, and colorectal cancer all responded equally well. As the treatment only depends on the cancer already being identified by the immune system, it probably works in all situations. “I do not think there are limits to the kind of tumor that we could treat. It is enough that it has been infiltrated by the cells of defense, “summarizes Levy.
In addition to the great results, a major advantage of the double agent is that one has already been approved for human use, and the other has performed well in several clinical trials. If they are as effective for us as they are for mice, the new solution is likely to get off the ground quickly – and start using it right away with real patients.