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Cancer treatment innovations are of continued interest to medical professionals, people diagnosed with cancer and their caregivers.
Recently, with support from the National Institutes of Health, a team of scientists created a kind of synthetic protein called a chimeric antigen receptor (CAR) that could increase the effectiveness of immunotherapies that target solid tumors.
Additionally, the CAR could trigger the body’s immune system to directly attack the tumors — a response that may be instrumental in getting rid of cancer in a person’s body.
The Engineered Protein Changed the T Cell Response
As people go about their lives, their immune systems look for foreign cells that could cause damage. The surface of each one contains a protein called an antigen that stimulates the body to recognize it as an invader and create antibodies as a defense.
Furthermore, the immune system contains white blood cells, called T cells, that can find damaging cells and limit their effects. The T cells have proteins called receptors that recognize and attach to particular antigens. When that happens, various processes make the T cell counteract the antigens.
However, the process described above often fails to have a detrimental effect on solid cancerous tumors. That’s because those growths secrete immunosuppressive cytokines. They’re soluble proteins that shut down the immune system and make T cells unable to fight back against the antigens.
While in the lab, the research team created CARs to change how T cells respond to immunosuppressive cytokines. These CARs were effective against antigens on the surface of cells, as well as soluble ones. The scientists put the CARs onto the T cells, thereby making them active in the presence of soluble antigens and able to attack them.
What Could This Mean for Immunotherapy and Other Cancer Interventions?
Using a patient’s immune system as a cancer treatment mechanism is a strategy collectively known as adoptive cell transfer (ACT). The previously mentioned CARs fall under the ACT umbrella, and scientists recognize that CARs that positively affect T cells have only been studied at a minimum so far. In most cases, the associated small clinical trials were for patients with blood cancers.
However, this recent development could impact how physicians diagnose, monitor and treat cancerous tumors, too.
Doctors already have several resources at their disposal. One of them is nuclear medicine, which involves a radioactive material called a radiotracer that’s inhaled, injected into or eaten by a patient. The subsequent radioactive emissions get captured by a camera and then analyzed.
Regarding cancer, physicians often depend on nuclear medicine to find it in the body or determine whether treatments are working. Eventually, patients undergoing CAR treatments could go to nuclear imaging appointments to see if those immune system-based therapies have had the intended effects.
Moreover, this recent scientific achievement related to CARs and T cells is versatile, and that’s another promising factor about it. While experimenting, the researchers engineered several proteins that responded as expected to various types of soluble proteins, including the TGF-Beta cytokine, which could become a future target for emerging immunotherapies.
Another Effort to Use CARs on T Cells to Shrink Solid Tumors
The achievement of the UCLA researchers represents a very new development. It’s worth noting, though, that a clinical trial involving human subjects with pancreatic cancer began last fall at the University of Pennsylvania, and it, too, focused on CARs and T cell activation. The trial is currently in Phase I, which tests the safety of a drug. About 70 percent of medical advancements make it past that segment.
E. John Wherry, PhD. — director of the Institute for Immunology at the Perelman School of Medicine — clarified that besides investigating the efficacy of this kind of therapy on pancreatic cancer, the clinical trial also aims to look at ways to enhance the potency of this intervention.
He also brought up how, although pancreatic cancer is typically difficult to treat, researchers could refer to the previous research on CARs and blood disorders and use that material to inform these upcoming findings. Data about that clinical trial indicates the completion date isn’t until September of 2021, so that means people still have a while to wait before getting news about the outcome.
The use of synthetic proteins to stop cytokines from deactivating T cells is still in its early stages. However, developments in the process and its effects are undoubtedly promising, and they could be life-changing for current and future cancer patients.
Written by Kayla Matthews, Productivity Bytes.