Recent therapies include immunotherapy.Some progress has been made in this area in recent years, for which immunologists James Allison and Tasuku Honjo have received the 2018 Nobel Prize in Physiology or Medicine.
Researchers have laid the foundation for a novel form of immunotherapy.
What is immunotherapy based on?
In general, immunotherapy is intended to support and strengthen the immune system so that it can defend itself against the disease.
For example, immune system messengers were used to trigger a non-specific immune defense in the body.This can be used to fight pathogens and diseased cells, but this non-specific response for cancer cells was usually not sufficient.
Why are cancer cells not being fought by the immune system?
Cancer cells can disguise themselves as healthy cells
Cancer cells can camouflage in the body, so our immune system does not perceive them as diseased cells.
For this purpose, the cells use different methods.One of them influences certain control points of our immune system, so-called immune checkpoints. They sit on the T-cells that destroy pathogens or diseased cells.
Checkpoints regulate our immune response
The immune checkpoints can influence the response of T cells to pathogens and the body’s own cells.One can think of the checkpoints as switches to switch the T-cells on and off (or rather, to strengthen or weaken the immune response of our body).
Too strong an immune system would harm our body
A very aggressive immune system (i.e. “switched on” T-cells) would also accrue to the body’s own cells and trigger autoimmune reactions.
Cells can turn off the immune response
Therefore, it makes perfect sense that other healthy body cells have the possibility to “switch off” the T cells with this checkpoint, i.e. to protect themselves from an attack by the immune system if there is a risk that the immune cells will take action against them.
However, cancer cells also have this ability to “switch off” the T cells.Our immune system can no longer recognize and fight the cancer cells as a disease.
What does immunotherapy do?
This is where the new immunotherapy begins: it uses certain drugs (immune checkpoint blockers) that block these immune checkpoints and thus prevent the T cells from being “switched off”.
As a result, the T cells are permanently “switched on” or up-regulated and can now detect and fight the cancer cells.
Side Effects of Therapy
As explained above, a highly regulated immune system can pose a danger to healthy cells in the body.The side effects of this form of therapy therefore include autoimmune diseases.
It is therefore very important to find a balance between stimulation and inhibition of the immune system, so that such side effects can be avoided as much as possible.
Current state of research
The active ingredients of immunotherapy have already been successful in some cancers (black skin cancer, non-small cell lung cancer or bladder cancer) where conventional cancer therapies could no longer help.
Nevertheless, much research still needs to be done in this area, for example not all patients are talking about therapy (the reasons for this have not yet been clarified) and immunotherapy is still far from being used successfully for all cancers.