Scientists Discover “Living Drug” in Blood of Cancer Patient
Unusual T Cells Provide Advanced Cancer Treatment
Scientists have found an unusual “living drug” in the blood of a man who had an incurable form of cancer.
One year after receiving the “most advanced cancer treatment” in over 50 years, this patient’s body was still protected by a group of immune killer cells known as T cells.
And researchers at Cardiff University in the UK have found that these special T cells can recognize and attack tumors much better than normal T cells. It can even treat several different types of cancer at the same time from different angles.
Cardiff University biologist Andy Sewell explains: “Our results really surprised us because no one knew that individual T cells could recognize cancer cells with several different cancer-associated proteins at the same time. We wanted to know how some cancer patients were able to recognize cancer cells. End-stage and those treated with (tumor-infiltrating lymphocyte) therapy did not get rid of the cancer, so we were looking for answers.”
Over the past decade or so, tumor-infiltrating lymphocyte (TIL) therapy has emerged as a new and powerful method for advanced tumor eradication.
TIL treatment involves taking the patient’s own white blood cells directly from the tumor and artificially amplifying them to better attack the cancer.
And in clinical trials, the treatment works in more than 80% of cases.
Despite these amazing results, scientists still don’t know how the treatment works at the cellular level.
Cardiff researchers have been trying to figure this out for years, and now they’ve made a breakthrough.
Understanding the Mechanism
Looking at the results of phase I and II clinical trials in which 31 patients with malignant melanoma were treated with TIL, the researchers found that those who had their cancer removed still had a sustained T-cell response after more than a year.
The T cells from one of these patients were surprisingly “universal”, demonstrating the ability to respond to most types of cancer, not just skin cancer.
“More importantly, we have found large numbers of polyclonal T cells in the blood of people who have had cancer,” says Sewell. “Until now, we have not found such polyclonal T cells in people with advanced cancer.”
To confirm what’s really going on, Sewall and his colleagues now have to watch closely as these versatile T cells attack cancer in the lab.
Only then will they be able to determine whether these immune cells are responsible for the excellent results of TIL therapy.
Potential for Future Treatments
The researchers say we hope to find out if engineered pluripotent T cells can be used to treat a wide range of cancers, similar to how engineered CAR-T cells are currently being used to treat certain types of leukemia. CAR-T cells are chimeric antigen-receptor T cells that have already been approved for the treatment of leukemia by the US Food and Drug Administration.
CAR-T therapy is slightly different from TIL therapy because it reprograms specific T cells to target specific parts of the cancer cell.
Because TIL T cells come directly from a solid tumor, they are more versatile, and scientists don’t have to fiddle with their attack mechanisms as much.
Perhaps that is why they are so effective against many types of cancer.
The study was published in Cell.
Source: Science Alert
