Immunotherapy Outcomes Prediction: Scientists Discover Strategies for Foreseeing Response Success
Modern medicine is constantly evolving, and one of the latest advancements in the fight against cancer is immunotherapy. However, not everyone and every type of cancer can be treated with this innovative approach.
Researchers at Johns Hopkins University have recently made a significant breakthrough in this field. They've identified a specific subset of mutations in a cancer tumor that could indicate how receptive it will be to immunotherapy treatment.
These findings could help doctors more accurately select patients for immunotherapy and even predict the treatment's outcome. The research was published in the journal Nature Medicine.
So, what exactly is immunotherapy? In simple terms, immunotherapy is a treatment that boosts the body's immune system to fight off the disease. Usually, cancer cells develop mutations that make them hide from the immune system. Immunotherapy works by giving the immune system a boost, making it easier for it to find and destroy these cancer cells.
There are several types of immunotherapy, including checkpoint inhibitors, CAR T-cell therapy, and adoptive cell transfer. Immunotherapy is currently being used as a treatment for breast cancer, melanoma, leukemia, and non-small cell lung cancer. Researchers are also exploring its potential for other types of cancer like prostate, brain, and ovarian cancer.
In the past, doctors would use the total number of mutations in a tumor, called the tumor mutation burden (TMB), to try to figure out how well a tumor would respond to immunotherapy. However, the researchers at Johns Hopkins went a step further. They identified a specific subset of mutations within the overall TMB - which they call "persistent mutations" - that are less likely to disappear as the cancer evolves. This means that the cancer tumor remains visible to the body's immune system, enhancing the response to immunotherapy.
The researchers believe that the number of persistent mutations better identifies tumors that are more likely to respond to immune checkpoint blockade compared to the overall TMB. This could help clinicians more accurately select patients for immunotherapy and predict their clinical outcome with standard-of-care immune checkpoint blockade.
Dr. Valsamo Anagnostou, a senior author of the study and an associate professor of oncology at John Hopkins, explained, "Persistent mutations are always there in cancer cells. These mutations may render the cancer cells continuously visible to the immune system, eliciting an immune response that is augmented in the context of immune checkpoint blockade, allowing the immune system to continue eliminating cancer cells with these persistent mutations over time, resulting in sustained immunologic tumor control and long survival."
These findings could revolutionize the way cancer patients are selected for immunotherapy in the future. High-throughput, next-generation sequencing techniques could be used to study patients' mutational spectrum, categorizing patients by their likelihood of response to immunotherapy.
Dr. Kim Margolin, a medical oncologist and medical director of the Saint John’s Cancer Institute Melanoma Program, said, "It was refreshing to see this incredible article demonstrating that a highly-respective collaborative group has gone way beyond the simple concept of tumor mutation burden and to define persistent mutations, loss of mutation-containing sequences, and in a new light."
References:
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- The recent research by Johns Hopkins University scientists has identified a specific subset of mutations in cancer tumors, known as "persistent mutations," which could significantly improve the effectiveness of immunotherapy treatments.
- By understanding the presence of these persistent mutations, doctors may be able to more accurately select patients who are likely to benefit from immunotherapy, potentially revolutionizing the way cancer patients are treated in the future.
- The discovery of these persistent mutations adds a new layer to the ongoing scientific investigation into the applications of immunotherapy for various medical conditions, including cancer types beyond those currently treated, such as prostate, brain, and ovarian cancer.
