Its increasingly important role in prevention, treatment, and recovery
Long before there was modern life, there was cancer—and there was the potential for the body’s own immune system to conquer the disease. Now, more and more research is exploring the relationship between immunity and cancer, looking at how supporting the immune system can help at every stage of cancer, from prevention to treatment to recovery.
The science behind the immune system’s role in the development of effective cancer treatments has become so solid that “immunotherapy” (an umbrella term for several therapies that harness and strengthen the power of the immune system to attack tumours) has become known as the next pillar of cancer treatment, alongside surgery, chemotherapy, radiation therapy, and “targeted therapy.”
“Everybody recognizes that the immune system plays an essential role in cancer, particularly the innate immune system,” says Dr. Hal Gunn, founder and CEO of Qu Biologics and co-founder of InspireHealth, a leading supported cancer-care centre.
“When most people think of a tumour, they think of it as just being filled with cancer cells. Of course, there are lots of cancer cells in a tumour, but there are also a lot of immune cells in a tumour.
“One of the most important factors for determining prognosis in cancer is what those immune cells are doing,” Gunn adds. “In many cases, what the immune cells are doing is more important than what the cancer cells are doing. If those immune cells are supporting the growth of cancer and suppressing immune function, then the prognosis is poor. But if those immune cells are actively clearing the cancer, then the prognosis is good.”
Several recent advancements have occurred in efforts to help immune cells eradicate malignant cells. One of the most prominent has been the development of “immune checkpoint inhibitors.”
The immune system protects people from disease, with T-cells being a key type of immune cell. Cancer cells can trick the immune system by turning the T-cells off, stopping them from recognizing and destroying cancer cells. In this form of immunotherapy, checkpoint inhibitors turn the T-cells back on so they can discern and attack cancer cells.
Checkpoint inhibitors “essentially take the brake off the immune system to allow it to clear the cancer,” Gunn explains. However, there is a risk that the immune cells become overactivated, potentially leading to autoimmune disease where the immune system starts attacking healthy cells as well as the cancer.
“The ultimate goal is [to] understand how you can activate or restore normal immune function so that it will still have the appropriate modulation,” Gunn says. Qu Biologics is developing what it calls Site Specific Immunomodulators, which aim to stimulate the body’s normal immune response to identify and destroy cancer cells.
Other types of immunotherapies range from targeted antibodies and cancer vaccines to adoptive cell transfer and tumour-infecting viruses. Immunotherapy also shows promise because it can train the immune system to remember cancer cells, possibly resulting in long-lasting remissions.
As research into specific types of immunotherapies continues, the fact remains that supporting immunity can help at every stage of cancer, from prevention to treatment to recovery. The question, then, is: how can people activate the immune system to get it to do what it’s supposed to do?
“In the same way that our immune system is capable of being activated to clear cancer, the same principle applies to the prevention of cancer,” Gunn says. “The stronger, the more resilient, the more robust your innate immune system is functioning, the better capable it is of preventing cancer.
“Exercise plays a role in supporting innate immune function; healthy diet is very important in supporting optimal immune function; sleep is very important in supporting immune function,” Gunn adds. “Not surprisingly, if you do those three things well it reduces your risk of developing cancer. If you eat unhealthily, don’t exercise, and have poor sleep habits, all of those three things increase your risk for developing cancer.”
An active lifestyle with plenty of greens isn’t a guarantee against cancer, of course. “If you practise these healthy approaches to living, it does reduce the risk of developing cancer; it can’t invariably protect you,” Gunn says. “It substantially reduces the risk because there are many factors involved in the development of cancer—some of which you have some control over and some of which you don’t.”
Certain cancer treatments (such as chemotherapy, radiation therapy, surgery, and stem cell or bone marrow transplants) or the disease itself can suppress or weaken the immune system by lowering the number of white blood cells and other immune system cells.
It’s easier to get an infection when there aren’t enough white blood cells, particularly neutrophils, to destroy germs. Treatments can also cause these cells to work less effectively than usual, leading to what is known as immunosuppression. Consequently, bolstering the immune system throughout treatment is vital.
“It makes sense to optimally support your immune function during treatment,” Gunn says. “There’s a whole range of approaches, and some of the most important ones are nutrition, exercise, and things we all understand in a common-sense way that are good for our health. The reason they’re good for our health is because they support our immune function.”
A strong immune system also benefits recovery from cancer treatment. Regular exercise, for instance, not only increases a person’s energy level and sense of well-being, but also can make recovery faster and decrease the risk of cancer coming back.
Getting enough restful sleep is crucial. Sleeping can boost brain function, improve hormone function, and lower blood pressure.
In a sense, immunotherapy and supporting the immune system are the ultimate in precision, or personalized, medicine.
“To some degree, supporting immune health is individualized according to what is happening with your own health and your own life,” Gunn says. “It’s a lifelong learning process to understand how you can optimally support your health.”
Research points to three categories of natural products (which researchers describe as “compounds extracted and/or optimized from nature”) that are showing promising effects in cancer immunotherapy. Saponins, polysaccharides, and flavonoids seem to play a role in reversing tumour-induced immunosuppression.
Saponins are naturally occurring compounds found in many plants, including legume species, which appear to affect the immune system in ways that help protect the body against cancers.
Polysaccharides, found in fungi, algae, and some plants, can stimulate and regulate innate immunity, improving the effect of immunotherapy.
Flavonoids, present in fruits, vegetables, and green tea, wine, and cocoa, act to suppress cancer-cell proliferation and invasiveness.
Some supplements can provide immune support during cancer treatment. Check with your health care practitioner about any supplements that may interfere with conventional therapies.
The sunshine vitamin may prolong life in people with cancer. It helps control cell growth and immune function by regulating genes for cell differentiation, division, and death.
The essential mineral seems to protect normal cells against damage from chemotherapy and radiation and enhances the effect of treatment on cancerous cells.
The supplement combination is sometimes used to counteract chemotherapy toxicity without compromising its therapeutic effects.
Ginger extract supplements may help treat nausea, vomiting, and other gastrointestinal symptoms associated with cancer treatments.
More than two-thirds of the human body consists of water found inside cells. Much of the rest of the body’s fluid is “interstitial,” meaning “between the other places.” That fluid and the tissues connecting it make up the interstitium, which can be found everywhere just below the skin and in digestive, respiratory, and urinary systems (and which may be an entire organ in itself).
So where does the interstitium fit in with immunity and cancer?
The immune system and lymphatic system work together to maintain health. Interstitial fluid is the source of lymph, which releases white blood cells, the immune system’s infection fighters. The network of fluid-filled compartments crosses organ barriers and could serve as a conduit for tumour cells to spread.
Although research is ongoing, this may help to explain why cancers that start in one spot in the body often end up somewhere else despite not having an obvious path.