In the mid-1960’s a young biochemistry student made a choice that would change the course of scientific history: he became a dishwasher.

Dr. Tak Wah Mak says his career started when he took a job washing beakers and test tubes at a lab in Wisconsin. He began helping with the lab’s experiments, effectively launching a career in scientific research. In 1984, Dr. Mak cloned the receptor of a specific white blood cell called the T-cell, long considered to be a “Holy Grail” feat in science.

What’s so special about T-cells? For one thing, they can cure cancer. And they’re already inside your body.

T-cells are part of our immune system, our body’s way of protecting us from infection. Scientists have figured out how to harness the immune system’s power and turn it against cancer. 

“What’s so promising for immunotherapy is that it actually works,” says Dr. Ben Wang, the Research Head of the Immune Profiling Team at the Princess Margaret Cancer Centre in Toronto, Canada. “It’s certainly an exciting new strategy to treat cancer and, with more research, could become a cure for many types of cancer.”

A “cure for cancer” has been touted in headlines for generations and never fails to generate controversy. I’m sure you’ve heard the conspiracy theories, the majority of which revolve around Big Pharma. They claim that Big Pharma has found and is actively hiding a “miracle” cure for cancer so that it can continue to profit from treatment, and that Big Pharma invests in the more expensive cancer treatments, leaving the cheaper alternatives with insufficient funding to become widely available. 

The prevalence of such medical conspiracies is staggering; a 2014 study in the Journal of the American Medical Association by Dr. J. Eric Oliver and Professor Thomas Wood found that 49% of Americans believe in at least one medical conspiracy. It is true that research in science is often dependent on access to sufficient funding, which inspires reasonable anxieties about the results being biased towards whoever sponsored them. But the Big Pharma cancer conspiracies speak to a fundamental misunderstanding of how cancer works and what “curing” it really means. So, if you’re worried about missing out on a “secret” or “miracle” cancer cure, please take a sip from this nourishing cup of science and discover how this immunotherapy treatment actually works.

The Princess Margaret is one of the top five cancer centers in the world and boasts incredible immunotherapy success stories. Jeannette Edl, a woman with Stage 4 lung cancer underwent immunotherapy and saw her tumors shrink by seventy percent. Alan Taylor had Stage 4 melanoma spreading aggressively through his abdomen, his bowels, his lymph nodes, and his lungs; in September 2015, treatment with immunotherapy eradicated all but three small tumors. Jason Smith, diagnosed with lung cancer, underwent immunotherapy in 2016 and saw the tumors in his lungs shrink by thirty and fifty percent. He ran the Boston Marathon in the middle of treatment.

The science behind this groundbreaking treatment seems relatively straightforward: the T-cell’s role in the immune system is to attack infected cells and cancer cells. The T-cell uses its receptor to “recognize” those infected cells. Once the T-cell “sees” the infected cell or cancer cell, the T-cell multiplies and attacks. That is what constitutes an immune response.

“Your body already has the capability of detecting cancer cells, and the immune system fights it off as it would fight off an infection,” Dr. Wang explains to me.

Thanks to Dr. Mak’s discovery and new developments in artificial T-cell engineering, scientists are now able to genetically modify T-cells so that they recognize cancerous cells. In a type of immunotherapy called adoptive cell therapy, scientists grow those “activated” T-cells and put hundreds of millions of them back inside the patient. Now, the patient’s own body can recognize and fight cancer.   

Adoptive cell therapies are still in the early stages of clinical trials, however, another type of immunotherapy, which uses immune checkpoint inhibitors, is already considered a first-line of care treatment option for some cancers in Canada. 

The immune system uses proteins called checkpoints to stop the immune response from going too far and damaging healthy tissue. Cancer cells can turn on a checkpoint to “trick” the immune system into not attacking them. Treatment with immune checkpoint inhibitors uses drugs that allow the immune system to ignore these checkpoints and thus attack the cancerous cells. 

“For lung cancer it’s approved, for melanoma … it’s approved, also for renal cancer,” Dr. Wang tells me.

He adds that, in Canada, approval could be in the works for other disease sites, such as head and neck cancer.

This method had shown great success; for example, there is usually only a fifteen to twenty percent chance that patients with late stage melanoma will survive for five years. Dr. Wang explains that with this immunotherapy treatment, their chances of survival leap to thirty-four percent. 

“I think it’s definitely a good strategy because it’s enhancing something that your body already has. You already have these cells, and we’re just kind of unleashing them,” he says. 

Dr. Wang oversees of the collection and analysis of patient samples that the Princess Margaret obtains from clinical trials. His team aims to take what they learn from the research in the lab and apply it to new clinical trials. 

A trial called INSPIRE, which launched in March 2016, is testing a drug called Pembrolizumab, which enhances the immune system’s power to kill cancer cells. Over 100 patients are enrolled. Dr. Wang tells me.

“We collect blood and tissues from the patients at various points in time, and then we’re looking at how patients respond to treatment and changes in their immune profile. Do they have more T-cells after treatment? Do they have more activated T-cells after treatment?”

Dr. Lillian Siu, the principal investigator on the trial, says they are collecting important details about the patients who respond better than others. They are working to understand how to use the drugs effectively on a patient-to-patient basis. According to Dr. Siu, “I think that’s very important in personalizing immunotherapy.”

Patient personalization is where immunotherapy falters. While it has revolutionized how we treat cancer, Dr. Wang cautions that immunotherapy is not a one-size-fits-all solution. Some patients respond well, while others do not. Dr. Wang’s team is trying to figure out why.

“What’s unique to one group of patients versus another that allows them to respond? Will combining different immunotherapies give a better response? Should you treat with an immune checkpoint inhibitor or with adoptive cell therapy?” asks Dr. Wang. “There could be a lot of different factors that affect a patient’s response to treatment. There could be underlying genetic factors at play.”

The possible side effects of immunotherapy also depend on the individual patient and his or her overall health. Common side effects include flu-like symptoms, fatigue, and small rashes on the skin. More severe side effects involve the inflammation of various organs.  

The hospital has also begun a microbiome program to investigate how the gut, which has a significant influence on the immune system, affects patient response to immunotherapy. Dr. Wang tells me that stool sample collection and strategies to alter a patient’s microbiome may be in the works for the hospital.

Another exciting development is cancer vaccines. Unlike regular vaccines, which are administered before the onset of infection, a cancer vaccine is administered after the patient develops cancer. A sample of the patient’s cancer tissue is used to program the body’s T-cells to more easily recognize and kill all of the cancer cells. 

So, will immunotherapy finally lead to a world without cancer? According to Dr. Wang, we need to change how we think about “curing cancer.” 

“Immune checkpoint inhibitors and adoptive cell therapy do not prevent cancer, but they can be an effective way to treat it,” he explains. “Some cancers are genetic. Mutations occur and mutations are the cause of cancer. Environmental factors can also play a role … exposure to carcinogens can increase your risk of getting cancer.”

Cancer will occur. It’s in the behaviour of a cell. According to the Canadian Cancer Society, almost one in two Canadians will receive a cancer diagnosis in their lifetime. What “curing cancer” means is being able to successfully treat cancer – control it, prolong patient survival, and prevent relapse.  

And it looks like, for many patients and many types of cancer, immunotherapy is doing just that. 

“I think that’s the rewarding part of the whole thing – knowing that it’s effective,” Dr. Wang says. 

While there are still many questions that surround the treatment, Dr. Wang’s team has made unprecedented strides in answering them. 

When I ask Dr. Wang about how he ended up on such a revolutionary team, he tells me that, just before he completed his undergraduate degree, his father passed away from cancer. Dr. Wang decided he wanted to apply his immunology training in the field of cancer research. And this job just happened to be available when he finished his doctorate.

“I was lucky, I guess,” he says, laughing. “There’s nothing special about me, really.”