Cancer remains the second-leading cause of death in the United States. This year, an estimated 1.7 million new cases will be diagnosed, with nearly 610,000 people expected to die from the disease, according to the National Cancer Institute.

Fortunately, several recent cancer treatments show considerable promise. Among them is Chimeric Antigen Receptor (CAR) T cell therapy, which the American Society of Clinical Oncology recently named the "2018 Advance of the Year." Three USC Viterbi School of Engineering researchers - Assistant Professor Stacey Finley, Professor Pin Wang and Assistant Professor Nick Graham - have just published a paper in "Biophysical Journal" that sheds light on how this new treatment works, information that could one day result in better cancer therapies with fewer side effects.

"We're trying to dig into the molecular mechanisms," said Graham, an assistant professor of chemical engineering and materials science. "By understanding how the CAR T cells work, we could try to design better ones."

When the immune system functions normally, immune cells move around the body and look for pathogens that don't belong and kill them. However, cancer cells can mask themselves, making it harder for the good cells, such as T cells, to kill them.

With CAR T cell therapy, a person's T cells are removed, genetically engineered with proteins, and then injected back into the patient. The resulting CAR T cells are much better at fighting cancer cells. That's because these modified CAR T cells have an engineered protein receptor, the CAR, that can bind to cancer cells. When this occurs, a signal from the CAR tells the T cell to begin destroying the cancer by secreting the chemicals perforin and granzyme.