Cancer is considered a global health crisis, with diagnoses and deaths from cancer predicted to increase significantly in the next few decades. Immunotherapy for cancer could be the answer to treating this complex and devastating disease, using the patient’s own immune system itself to attack tumors.
June is cancer immunotherapy awareness month, dedicated to raising awareness about immunotherapy for cancer, educating patients and members of the public about how cancer immunotherapy works, and showcasing recent progress in the field of cancer immunotherapy. In this blog, we’re answering your questions about immunotherapy for cancer, discussing our own cancer immunotherapy research here at oNKo-innate, and celebrating the impact of cancer immunotherapy researchers around the world.
Understanding Immunotherapy for Cancer: The Basics
Just like cancer itself, immunotherapy is complex. Let’s investigate the basics: what is immunotherapy for cancer, how does immunotherapy for cancer work, the advantages of immunotherapy over traditional cancer treatments, potential side effects, and types of cancer immunotherapy.
What is immunotherapy for cancer?
Immunotherapy refers to a broad category of treatments that involve harnessing the power of the body’s own immune system to fight diseases like cancer in a targeted manner. While it’s only in the last few decades that cancer immunotherapies have become widely used, the first use of immunotherapy for cancer actually dates back to the late 1800s.
How does immunotherapy for cancer work?
Immunotherapy for cancer works by either boosting the immune system so it is better able to detect and kill cancer cells, or removing the roadblocks that may have been exploited by the cancer to prevent the immune system from recognizing and responding to the cancer cells in the first place.
In a healthy person, the immune system is constantly dealing with threats, like infections and cancer cells – it’s actually quite incredible at its job. Cytotoxic lymphocytes, like killer CD8+ T cells and natural killer (NK) cells, are the ‘soldiers’ of the immune system, fighting cancer cells on the front line. These cells have different mechanisms that allow them to recognize both healthy cells and ‘non-self’ or cancerous cells, killing the latter.
However, because cancer cells develop from healthy cells, they are a bit trickier for cytotoxic lymphocytes to recognize as non-self, and tumors often exploit these signals to inhibit or evade recognition by the immune system. Cancer immunotherapy restores the ability of the immune system to recognize the cancer cells as non-self and/or supercharges the cytotoxic lymphocytes so they are more efficient at killing tumors.
Immunotherapy for cancer vs. traditional cancer treatments
Immunotherapy for cancer can offer some key advantages over traditional treatments such as chemotherapy and radiation therapy: it is often more precise and more durable, offering greater potential for lifelong cures.
Let’s take chemotherapy as an example. There are different types of chemotherapy, but they all work by killing rapidly dividing cells, like cancer cells. Unfortunately, this means that they also kill any other cells in the body that are actively growing and dividing – including healthy ones, such as those found in hair follicles. The reason chemotherapy has such significant (and unpleasant) side effects is because it is toxic to healthy tissues with dividing cells, like the skin, digestive system, reproductive system, and bone marrow.
Unlike chemotherapy or radiation, immunotherapies are designed to trigger the immune system to attack cancer cells, while reducing the impacts on healthy cells and tissues. This is particularly important in treating childhood cancers, where chemotherapy regimens typically result in long-term damage and unwanted side effects, such as sterility.
Are there any cancer immunotherapy side effects?
Yes, patients can still experience side effects when treated with immunotherapy for cancer. However, these are not because the treatment itself is toxic to any healthy tissues, but rather due to an overstimulation of the immune response. Cancer immunotherapy side effects vary considerably from patient to patient and depend on the type of immunotherapy and duration of the treatment.
Common side effects of immunotherapy for cancer include fatigue, headaches, skin rashes, muscle and joint aches, nausea and vomiting, and flu-like symptoms such as fever and chills. While some side effects can be severe, most are quite manageable.
Types of cancer immunotherapy
The main types of cancer immunotherapy include cytokine therapy, immune checkpoint inhibitors, oncolytic virus therapy, cellular immunotherapy, monoclonal antibodies, and cancer vaccines.
There are now many different kinds of immunotherapy for cancer that have different modes of action. The type of cancer and the individual features of a patient’s tumor will determine the types of cancer immunotherapy drugs that are best suited. An immunotherapy for cancer may be administered on its own or as an adjuvant, meaning that it is given alongside other cancer drugs. In some cases, combination immunotherapy is used. Let’s take a look at the broad categories of immunotherapy for cancer and how they work.
Table 1: Types of Cancer Immunotherapy and Their Mode of Action
| Type of Cancer Immunotherapy | Mode of Action |
|---|---|
| Cancer vaccines | Cancer vaccines encourage the immune system to mount an anti-cancer response by helping immune cells recognize cancer cell antigens. They can be preventative or therapeutic. |
| Monoclonal antibodies (mAbs) | mAbs are lab-produced antibodies designed to bind to a specific target on either immune or tumor cells and stimulate an immune response against cancer cells. There are many types of mAbs with different functions. |
| Cellular immunotherapies | Cellular immunotherapies, otherwise known as adoptive cell transfer, involve taking a patient’s own immune cells or using cells from a healthy donor, growing them in large numbers, and administering them as a ‘living drug’ to attack tumors. The cells can be modified in vitro in the lab to improve their capacity to recognize cancer cells or increase their anti-tumor activity. Types of cellular immunotherapies for cancer include tumor-infiltrating lymphocyte (TIL) therapy, chimeric antigen receptor (CAR)-T cell therapy, and natural killer cell therapy. |
| Immune checkpoint inhibitors | Immune checkpoint inhibitors (ICIs) are drugs designed to treat tumors that have co-opted key immune checkpoints to block the ongoing recognition by the immune system. By preventing immune checkpoint proteins from binding to their target on immune cells (or vice versa), this type of therapy switches immune cells back ‘on’, restoring their ability to recognize and kill cancer cells. ICIs are currently the most widely used type of immunotherapy for cancer. |
| Cytokine therapy | Cytokines are the signalling molecules of the immune system, allowing cells to communicate and orchestrating immune responses. Cytokine therapy involves using recombinant – and in some cases, modified – cytokines to further activate the immune response against cancer, particularly cytotoxic lymphocytes like CD8+ T cells and natural killer cells. |
| Oncolytic viruses | Oncolytic viruses infect cancer cells in a specific manner. By injecting tumors with oncolytic viruses, the cancer cells will die, triggering an immune response. Oncolytic viruses can also be modified to deliver specific genes into cancer cells that will encourage the immune system to attack them. |
| Multi-specific Immune Engagers | Immune engagers, or multi-specific antibodies, are designed to bind to two or more targets on both tumor cells and immune effector cells. They act as a bridge, forcing the immune cell and cancer cell together and helping immune cells find and kill tumor cells that they otherwise might not have detected. |
Can Immunotherapy Cure Cancer?
Now that we’ve explored how immunotherapy for cancer works, and its advantages over other common cancer treatments, you’re likely asking the obvious question: can immunotherapy cure cancer? In some cases, the answer is yes, but it’s not so simple. Let’s explore the effectiveness of immunotherapy for cancer and how we’re creating safer, more powerful cancer immunotherapies here at oNKo-innate.
How effective is immunotherapy for cancer?
While immunotherapy is becoming an increasingly common treatment option, it cannot treat all types of cancer. For some tumors, even the best cancer immunotherapy will not produce a response. In the case of solid cancers, what really determines if current immunotherapies will work is whether the tumor is hot or cold.
Many tumors are immunologically ‘cold’, meaning that they have little to no immune activity. These cold tumors are able to fly under the radar of the immune system, evading detection and growing unchecked. Because of this, they are extremely unlikely to respond to common cancer immunotherapies like immune checkpoint inhibitors (ICIs).
One of the key goals in the field of immunotherapy for cancer is to ‘heat up’ these cold tumors, allowing them to be recognized by the immune system, increasing their infiltration by cytotoxic lymphocytes, and making them sensitive to immunotherapies like ICIs. At oNKo, this is one of our major areas of research and innovation. Curious about cold tumors and why they are such a problem? Read our full article below.
Next-generation immunotherapy for cancer: cytokine checkpoint inhibitors and more
Here at oNKo-innate, our goal is to create effective cancer immunotherapies that can treat a broad range of solid tumors, including cold tumors, while avoiding harmful side effects. To that end, we are pursuing multiple avenues of research, including next-generation cytokine therapies, cytokine checkpoint inhibitors, and cellular immunotherapies.
Our oNKo-001 and oNKo-044 assets are both promising cytokine therapies, based on the powerful interleukin-12 (IL-12) cytokine. With potent anti-tumor activity, extended half-life, and an improved therapeutic window, these candidates are poised to revolutionize the treatment of solid cancers, heating up cold tumors that do not respond to iICIs.
We believe that by expanding the definition of immune checkpoints, we will be able to create more effective immunotherapies for cancer, as evidenced by our oNKo-037 therapy. An interleukin-15 (IL-15) cytokine checkpoint inhibitor, oNKo-037 is designed to increase one of three signals crucial for the activation of CD8+ T cells and increase the function and fitness of natural killer cells. This molecule is also able to heat up cold tumors, allowing them to respond to ICIs and making it ideal for use in combination immunotherapy.
We are also exploring multiple targets that have the potential to improve cellular immunotherapies for cancer, including genetic modifications and checkpoints in T cells and natural killer cells. The most crucial aspect of our research is that we aren’t trying to cure any particular type of cancer, but rather generating treatments that overcome immune roadblocks across a variety of solid tumors. Our modality-agnostic approach and advanced discovery platform allow us to pursue any potential target in any immune cell type to achieve this goal.
Cancer Immunotherapy Awareness Month: Learn More and Get Involved
Cancer immunotherapies have enormous potential, but more research and innovation are needed before these treatments are able to cure all types of cancer. Fortunately, we’re seeing massive progress in this area; in the last decade alone, new tools have become available that can help us generate more effective immunotherapies for cancer, including artificial intelligence and CRISPR gene editing.
This cancer immunotherapy awareness month, we’re celebrating all of the researchers in academia and industry that do such amazing work pushing the field of immunotherapy for cancer forward. From creating more effective immunotherapies to deepening our understanding of why some patients do not respond to immunotherapy for cancer, these researchers are dedicating their careers to providing better clinical outcomes for cancer patients.
To get involved in cancer immunotherapy awareness month, you can donate directly to support cancer immunotherapy research through the Cancer Research Institute’s website. CRI also have a range of activities and events throughout cancer immunotherapy month each year where you can learn about immunotherapy for cancer and all the latest advances in this exciting field. Many of these virtual events are available on YouTube if you missed them, including this amazing fireside chat with cancer immunotherapy experts.
If you enjoyed this article, don’t forget to explore the rest of our learning centre for more information on cancer research and our own approach to immunotherapy for cancer. The field of cancer immunotherapy has been gaining huge momentum in the last few years, and we believe we are closer than ever to a cancer-free future. Do you have more questions about immunotherapy for cancer? Get in touch with us on LinkedIn and X.