On the Brink of Curing Cancer: How Nobel Prize Winners Offer Hope
The way we understand cancer treatment in the U.S. is changing. This year’s Nobel prizes in medicine honored new scientific breakthroughs that suggest we may be close to finding a cure for cancer.
One of the Nobel-prize winners, Dr. James P. Allison, has made great strides in advancing cancer immunotherapy. Immunotherapy is a treatment that augments the body’s ability to utilize its own immune system to fight malignant tumors. This innovative treatment has given hope to thousands of cancer patients who have limited options in treating their disease. It has also opened up many new avenues for cancer research.
But if the groundbreaking treatment offers so much promise, why have so many cancer patients, and even doctors, not heard of it? And of those who have, why are many so skeptical? According to Dr. Daniel Chen, oncologist and researcher at Stanford University, the doubt and uncertainty that surrounds immunotherapy is simply due to its novelty. “The emergence of cancer immunotherapy has occurred so quickly,” he said, “it’s hard for scientists, let alone physicians and patients, to keep track of it all.”
So what exactly is immunotherapy?
Until recently, there were only three options for treating cancer: surgery, radiation, and chemotherapy. While surgery has been around for thousands of years, radiation therapy was discovered in the late 1800s, followed by chemotherapy in 1946 as a result of chemical warfare research. More recent treatments also include poisoning cancer by preventing tumors from getting nutrients and blood supply.
These treatment methods are unfortunately only effective in about half of all cancer cases. While on the one hand this is a feat, on the other, it’s still a death sentence for many. According to the World Health Organization, in 2018, 9,055,027 people around the world received that death sentence. Immunotherapy offers another treatment option that may help to reduce that death toll.
Our immune system provides us with the best defense against diseases. It’s responsible for protecting our bodies against foreign invaders, and normally, it does a great job. But with cancer, the immune system unfortunately isn’t always successful. For over a hundred years, scientists have struggled to figure out why. That’s where Dr. Allison’s research comes in.
His biggest discovery was that the immune system wasn’t ignoring cancer, but that cancer actually found ways to evade the immune system. Using tricks that are designed to shut the immune system down, cancer escapes attack. But Allison found a way to block the tricks and get the immune system’s T-cells to target cancer like it would any other foreign invader.
Using Checkpoint Inhibitors
In 1994, Allison’s immunology lab at the University of California, Berkeley discovered that a protein on the T-cell called CTLA-4 was designed to stop the immune system from attacking healthy body cells. This is the “trick” that cancer utilizes to stay alive. The researchers then created an antibody that blocked the CTLA-4 protein, also called a checkpoint, and allowed the immune system to keep on attacking.
This discovery not only cured many cancer patients of their disease, but also opened up the floodgates for new immunology-based cancer research. The goal was to find checkpoints that might be even more effective than CTLA-4.
One such checkpoint is called PD-1, and it was discovered by Dr. Tasuku Honjo of Kyoto University, the other winner of this year’s Nobel prize. The body uses PD-1 cells as a signal to other cells to let them know that they’re safe and don’t need to be attacked. Again, cancerous cells utilize this process by tricking T-cells into thinking that its cells are normal. Honjo found a way to block this “secret handshake” between cancerous cells and the immune system, which ultimately created an effective way to kill cancer.
Most recently, in 2015, scientists discovered the “second generation” of checkpoint inhibitors, known as anti-PD-1 or anti-PD-L1. This is the type of drug that cured former U.S. President Jimmy Carter of his aggressive liver and brain cancer. Keytruda, or what many people call “the Jimmy Carter drug,” is one of the most widely used cancer drugs in the U.S. It’s currently used against nine different kinds of cancers.
The Future of Immunology
Researchers have barely begun to scratch the surface of all that immunology can offer us. They don’t yet know all there is to know about the relationship between cancer and the immune system.
Researchers refer to our current time as their “penicillin moment,” hearkening back to the days when the powerful drug was discovered. Its discovery opened up many new possibilities and sparked years of more research and medical breakthroughs.
Checkpoint inhibitors have only just been discovered. If this is the “penicillin moment,” then we can be sure that scientists will come up with many more effective treatments in the future.
Checkpoint inhibitors are not the only form of immunotherapy. There are currently 940 cancer immunotherapeutic drugs being tested in clinics by more than half-a-million cancer patients. Additional trials are also testing patients with a combination of immunotherapy and chemotherapy or radiation treatments.
Among the techniques currently being tested is adoptive cell transfer, which uses extracted T-cells re-injected into a patient to attack each cancerous cell. Another technique is chimeric T-cell therapy, or CAR-T. CAR-T takes a patient’s T-cells and forms a living drug that can wipe cancer out. It has already been successful in eradicating certain kinds of pediatric leukemia.
Dr. Axel Hoos, immunologist and former global medical lead at Bristol-Myers Squibb, says proudly that “the word cure can now be used in oncology.” Although doctors can’t promise to cure every kind of cancer in every patient, they can now cure some. Immunology isn’t fool proof, and it isn’t a guarantee. But many cancer patients who have responded to these treatments call it a lifesaver.