Cancer Immunotherapy in the 21st Century: Types, Progress, and More

Immunotherapy is a form of cancer treatment that strengthens the body’s natural defenses against malignant diseases. It uses substances that either the body or medical lab technicians created to improve how the immune system locates and destroys cancer cells.

How the Immune System Fights Cancer

The immune system has complex functions that allow the body to fight diseases and infections. This process involves the organs, proteins, and cells. Cancer is an unpredictable illness that can penetrate the immune system’s defenses, allowing cancer cells to grow and divide.

There are many different types of immunotherapy treatment. Some help the immune system slow the growth of cancer cells or stop it completely, while others help the immune system destroy cancer cells or stop the cancer from spreading to other areas of the body. An oncologist may order immunotherapy treatments alone or combine them with more conventional methods, including chemotherapy and radiation therapy.

Types of Immunotherapy Treatments

Those in the field of cancer research and treatment development have introduced many immunotherapy options throughout the years. They include:

  • Monoclonal antibodies and tumor-agnostic treatments, such as checkpoint inhibitors
  • T-cell therapy
  • Oncolytic virus therapy
  • Cancer vaccines

Allow us to discuss each of these treatments further below.

Understanding Monoclonal Antibodies and Tumor-Agnostic Treatments

The immune system creates antibodies when it detects something harmful in the body. Antibodies, also called immunoglobulins, are Y-shaped proteins that identify and neutralize infection by attaching to antigens, which are unique molecules that stimulate an immune response.

Medical lab technicians create monoclonal antibodies to improve the body’s own antibodies or act as antibodies themselves. Monoclonal antibodies help defend against cancer cells in different ways. For instance, they can obstruct the activity of abnormal proteins in cancer cells through targeted therapy, which targets a cancer’s genes, proteins, and the specific tissue environment that allows a tumor to grow and thrive.

Other types of monoclonal antibodies enhance immune system functions by blocking or stopping immune checkpoints. The body normally uses an immune checkpoint to hinder the immune system’s response naturally and prevent it from attacking healthy cells. However, by activating these checkpoints, cancer cells obtain the ability to hide from the immune system. Checkpoint inhibitors impede cancer cells from stopping the immune system to activate, and in turn, power the immune system to destroy cancer cells. The common checkpoints that these inhibitors affect are CTLA-4 and PD-1/PD-L1 pathways.

The United States Food and Drug Administration (FDA) has approved many checkpoint inhibitors for certain cancers through the years. There are also checkpoint inhibitors used to treat tumors in different areas of the body, focusing on specific genetic changes. Scientists refer to them as tumor-agnostic treatments.

Understanding Non-Specific Immunotherapies

Non-specific immunotherapy treatments do not attack cancer cells specifically. Instead, they stimulate the immune system in a more general manner, which can sometimes result in a better immune response against malignant cells.

Most people get this form of therapy after or with other cancer treatments, such as radiation therapy or chemotherapy. Sometimes non-specific immunotherapies are the primary cancer treatment. Some of the common immunotherapies in this category include the proteins interferons and interleukins.

Understanding T-Cell Therapy

T cells are immune cells that play an important role in fighting infections. In T-cell therapy, a doctor removes T cells from the blood. Then, a medical lab technician will add specific proteins called receptors to the cells, which will allow the T cells to identify cancer cells.

The doctor will then place the altered T cells back into the body. Once there, they will actively find and attack cancer cells. This therapy is called “chimeric antigen receptor (CAR) T-cell therapy.” This treatment works best for addressing certain blood cancers. Similar to other cancer treatments, side effects can occur. In CAR T-cell therapy, fevers and elevated blood pressure are some of the common side effects.

Researchers are conducting further studies to determine other ways to modify T cells to destroy different types of cancer.

Understanding Oncolytic Virus Therapy

Oncolytic virus therapy uses viruses that scientists have modified in a laboratory to kill cancer cells.

In this particular treatment, a doctor will first inject the genetically-changed virus into the tumor. Once inside, the virus will penetrate the cancer cells and create a copy of itself. The cancer cells burst and die in the process. As the cells die, they release proteins that stimulate the immune system to target other cancer cells in the body with the same proteins as the dead cancer cells. The virus will not enter healthy cells.

The FDA approved the first oncolytic virus therapy in 2015, which treats advanced stages of melanoma that surgery cannot address. Talimogene laherparepvec (Imlygic) or T-VEC is the virus used in this treatment. It is an altered version of the herpes simplex virus that causes cold sores. An oncologist can inject T-VEC into melanoma sites until there are no more cancer cells left.

Common side effects of oncolytic virus therapy may include fatigue, fevers, chills, and nausea. Some people also experience flu-like symptoms, as well as pain and discomfort at the injection site.

Clinical trials all over the world are reviewing other oncolytic viruses for different cancers. Researchers are also testing how specific viruses react when combined with other treatments, such as chemotherapy.

Understanding Cancer Vaccines

A cancer vaccine deliberately exposes the immune system to foreign proteins called antigens, causing the immune system to recognize and attack that antigen or related substances. There two types of cancer vaccine are prevention vaccines and treatment vaccines. For example, the HPV vaccine can help prevent cancer in the mouth or throat, anus or rectum, penis, cervix, vagina, and vulva.

Conclusion

Immunotherapy is an important approach to discover new treatments for cancer. The examples above do not include every immunotherapy treatment available, as researchers are still studying many new drugs and techniques. Nonetheless, the future of cancer treatment is brighter than ever with the introduction of immunotherapy in modern medicine.

Is Immunotherapy Right for You?

Our comprehensive cancer care specialists here at New Hope Unlimited can map out a treatment plan for your unique cancer case. To determine if immunotherapy is right for you, call us at 480-666-1403 to schedule a consultation.

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