Ultrasound energy is being studied as a method for activating cancer-fighting molecules in CAR T cells.
In the future, battling cancer may no longer entail harsh chemotherapy, but genetically modified immune systems that can be “remote-controlled.” That is currently the goal of UCSD researchers who are looking into whether ultrasound waves can control T cells in order to generate a new kind of cancer therapy.
The treatment builds on CAR T-cell therapy, which has revolutionized cancer treatments. During CAR T-cell therapy, doctors reengineer a patient’s T cells, which are part of the immune system, to detect and battle cancer. The technique has just been licensed for use in non-solid tumors thus far.
Researchers have been looking for a method to stimulate the immune system to target solid tumors without also causing T cells to attack essential organs, such as the lungs or liver.
Using microbubbles to fight cancer
In August, Dr. Peter Yingxiao Wang, a bioengineering professor at UCSD and co-author of the study, wanted to see if remote-controlled ultrasound might help develop a new type of targeted CAR T-cell therapy in a research published in Proceedings of the National Academy of Sciences.
In this early study, Wang and his colleagues concentrated on developing T cells that responded to ultrasound waves in order to activate them.
The team was able to tap into a field of study known as “mechanobiology.” It concerned how a cell understands, feels, and responds to external stimuli.
The researchers treated T cells with a “mechanosensor” and microbubbles to make them “see” the ultrasound waves. They were subsequently genetically modified to target cancer cells, allowing them to be “remote-controlled” cancer treatment.
“We adapt and twist things a little,” Yang said in order to understand how they made the cell capable of regulating its actions.
“The ultrasound is a sound with a high frequency that is similar to the sound made by a hammer,” Yang explained for Healthline.
Yang may theoretically use ultrasound waves to inject a patient with engineered CAR T cells that won’t “activate” unless they are targeted by an ultrasound beam.
It may mean that a person with a liver or lung tumor, for example, might be treated with the CAR T cells and that the cells would only start to attack if the ultrasound machine was utilized in the location of the tumor.
Because the cells would be less likely to mistake critical organ tissue for cancer tissue, this method would safeguard the patient’s healthy tissues.
This research is still in the preliminary stages and has not been shown to be effective on cancer patients. However, Wang believes that it may help advance CAR T-cell therapy research by providing a new route for studying it. “This study may eventually lead to a unique precision and efficiency in CAR T-cell immunotherapy against solid tumors while minimizing off-tumor toxicity,” he added.
Is there a cure for cancer on the horizon?
“It’s a pretty fantastic concept,” said Dr. Rebecca Gardner, an oncologist at Seattle Children’s Hospital. “The fact that it’s anatomically specific is what makes this study so unique,” she added, noting that you need the ultrasound machine to activate only the CAR T cells in a particular area.
Dr. Robert Gardner went on to explain that CAR T-cell treatments are presently being utilized for diffuse blood diseases like leukemia. However, because a solid tumor has greater dangers than a blood cancer, it might be better to utilize CAR T-cell therapy for solid tumors only.
Dr. Jonathan Gardner, a professor of radiology at the University of Utah School of Medicine, said that now ensuring that these therapies don’t harm normal tissue or induce harmful side effects in patients is difficult. A more extensive study will be required to keep people safe.
“We’ll want to better regulate where CAR T cells are and when they’re expressed, as well as when they don’t express,” Gardner said.
However, she added that this study builds on previous work looking at the effect of CAR T-cell therapy on solid tumors, including brain tumors.
Dr. Nicole Gardner, a doctor who specializes in pediatric brain cancer and regenerative medicine at Children’s Memorial Hermann Hospital in Houston, agreed. “I believe perhaps the next thing where CAR T cells can be beneficial is brain tumors,” she said.
It’s possible that your head doesn’t have a strong immune system, making it simpler to tamper with.”However, she warned that this area of study will require much more study before any of these treatments are utilized on a large scale.
“There are several compelling reasons for cell destruction in solid tumors that prevent the immune system from reaching and functioning,” she added. “It’s not as easy as saying, ‘Here’s a CAR T cell for a solid tumor.’”