Immunotherapy: A Modern Treatment For Cancer
Scientific advancements have grown by
Scientific advancements have grown by leaps and bounds in recent decades. Medical science has not been left out of this great leap forward and cancer research is one such field. Apart from a better understanding of the disease, we also have a host of novel treatments for cancer.
One of these breakthrough treatments for cancer is Immunotherapy. Immunotherapy is a type of targeted therapy or biologic therapy that uses the body’s natural immune system to kill cancer cells. Cancer immunotherapy is known by other names such as immuno-oncology.
The immune system helps the body to ward off diseases and illness, both caused by external as well as internal factors. However, the immune system cannot detect cancer cells since cancer cells lack the external markers that the immune system uses to identify hostile bodies, essentially ‘hiding’ from the immune system. The cancer cells can also signal the immune system to not destroy them or the immune system may be too weak to destroy cancer cells even if it can identify them.
This is where immunotherapy steps in. The immune system should be able to destroy tumour cells and immunotherapy is a way to help the body’s immunity to do that.
Types Of Immunotherapy
It can be difficult to clearly categorise different types of immunotherapy due to overlap and use of combination therapy to treat cancer. The most common types of immunotherapy include:
Monoclonal antibodies are synthetic antibodies made in a laboratory. Usually, antibodies are produced by the immune system in response to a threat, and these antibodies find and target the threat to eliminate it from the body. Monoclonal antibodies work in a similar manner.
Monoclonal antibodies can help the immune system to find cancer cells by interfering with the proteins of the cancer cells so that they become visible to the immune cells. It can also help to weaken the cancer cells so that they can be destroyed by the immune system.
Cytokines are a type of protein that helps the body destroy abnormal or dangerous cells. Cytokines include proteins such as Interleukin and Interferon.
These proteins interfere with the division and growth processes of cancer cells, boost the functions and growth of killer T-cells, and make cancer cells more visible to the immune system.
These inhibitors cancel out the effect of proteins produced by cancer cells that stop the immune system from killing them. This allows the immune system to find them and destroy them.
Checkpoints refer to the proteins present on the surface of T-cells (killer cells in the immune system) that turn ‘on’ in response to a threat and turn ‘off’ when needed. This helps to activate and deactivate the killing functions of the T-cells.
Cancer cells switch off the checkpoints on T-cells so that they are not attacked and checkpoint inhibitors turn these back on.
It may sound impossible but there is such a thing as vaccines against cancer and they are a type of immunotherapy.
Cancer vaccines are designed to identify certain protein markers on cancer cells. They can then work to inhibit the growth of abnormal cells, remove abnormal growths that couldn’t be reached with other treatments, and prevent the re-growth of cancer cells.
Adoptive cell transfer
This is the latest type of immunotherapy and may be offered as a part of clinical trials. Adoptive cell transfer refers to the transfusion of T-cells into the patient’s body. T-cells are a type of white blood cells or lymphocytes that destroy threats in the body such as pathogens and abnormal cells.
The most common type of adoptive cell transfer CAR T-cell therapy (CAR- Chimeric Antigen Receptor). Doctors take a sample of T-cells from the patient, genetically engineer them so that they can differentiate them cancer from normal cells, multiply these modified T-cells, and return them to the patient’s body.
Immunotherapy is a novel approach to cancer treatment and it works in many cases where other conventional treatments like chemotherapy and radiation don’t. While some types of immunotherapy are still being perfected, they are a glowing beacon of hope for cancer treatment.