Beating Cancer At Its Own Game

How immunotherapy is reinventing how we fight cancer and improving the chances of many cancer patients.

By Eden Bartlett

image: Cancer cell, Google Images

What if oncology’s secret weapon against cancer lies beneath your very skin? According to Suzanne L. Topalian, Professor of Surgery and Oncology at Johns Hopkins School of Medicine, your body may be the “ideal anti-cancer agent.” In a talk presented at University of Maryland, Baltimore County, Topalian described the latest breaking developments in immunotherapy, which utilizes a cancer patient’s immune system to fight tumors. By “reactivating” the immune system using newly developed drugs, Topalian and other oncologists believe immunotherapy can be used in conjunction with other traditional therapies to more effectively treat and prevent the reemergence of many kinds of cancer.

“With all their wonderful properties, the immune system should work against cancer,” Topalian said, pointing to the many mechanisms that the immune system utilizes to attack foreign invaders, “but it’s stalled by cancer cells because [they] put up all walls against immune attack.” Cancer cells act like invaders that essentially prevent the immune system from attacking them by thwarting a particular checkpoint that T-cells use to determine when to attack a foreign body. T-cells will usually attack a group of cells if they recognize them as foreign—but in the case of many cancers, the tumor emits a molecule that turns the immune attack off, allowing the tumor to grow unchecked.

“If we could devise a drug that would reactivate the immune system in the proper way, this drug could become a common denominator in cancer therapy,” Topalian stated. Drugs can be used to target this particular checkpoint so that tumors cannot trick the immune system into allowing them to continue to grow. By blocking the T-cells from recognizing the tumor’s emitted molecule, the tumor will not pass the checkpoint, and the immune system’s natural T-cells will attack and repress the tumor’s growth. In this way, the immune system can be “reactivated” to fight against the tumor like it would against any other foreign invader, like an infection or virus.

Trials utilizing these drugs are already underway, and the results appear promising. In one case study, a patient with lung cancer saw the regression of multiple tumors after using drugs targeting this pathway. Prior to the trial, this patient had been given a life expectancy of only a few months—but with the immunotherapeutic drugs, the patient continued to see improvement for years.

Currently, randomized clinical trials are underway to further study the effects of immunotherapy drugs.

“The gold standard is overall survival,” said Topalian. “There’s a lot of reasons to be excited about these treatments which can break down the walls of cancer.”