How does the body fight cancer

Immunotherapy - Can the Immune System Fight Cancer?

The task of the immune system is to defend itself against pathogens and fight damaged cells. The prerequisite for this, however, is that the damaged cells show significant changes compared to healthy tissue. Cancer cells often do not show such clear characteristics, and the cancer cells can change and develop further very quickly. This allows them to develop evasive strategies against an immune response over time, for example by making themselves "invisible" to the immune system or by inhibiting the immune reaction.

Immunotherapies - A Promising Approach to Research in Combating Cancer

A general, unspecific strengthening of the immune system is not enough to fight cancer. Immunotherapies are designed to strengthen the immune system to such an extent that it can destroy cancer cells on its own. Immunotherapies are all methods that use the body's immune system to fight cancer.

An example of an immunotherapy approach is the use of checkpoint inhibitors, a type of antibody that specifically targets "brakes" in the immune system. These checkpoints normally prevent an excessive reaction of the immune system (so-called autoimmune reactions) against the body's own healthy cells. Some tumors specifically activate such "immune checkpoints" so that immune cells that actually recognize and fight the tumor are severely weakened. So-called immune checkpoint inhibitors or checkpoint inhibitors counteract this: They prevent the suppression of the immune response and thus cause the immune system to attack the tumor more intensely.

Promote research on immunotherapies

As part of its institutional funding, the BMBF funds non-university research institutions in the field of cancer research such as the German Cancer Research Center (DKFZ), the National Center for Tumor Diseases (NCT) and the German Consortium for Translational Cancer Research (DKTK). This year, well over 200 million euros will be made available for cancer research.

The DKFZ, NCT and DKTK primarily pursue innovative “next generation” approaches in their research on immunotherapy procedures. An important research area at the DKFZ is, for example, the development of tumor vaccines, i.e. cancer vaccines. Cancer vaccines are supposed to produce a reaction against tumor antigens. To do this, these proteins or sections of them are vaccinated together with substances that strengthen the immune response. As an alternative to the finished protein as a cancer vaccine, its genetic blueprint, i.e. a piece of genetic material, can also be used as a vaccine. Or you use whole tumor cells that are no longer capable of growth and "show" the immune system several possible tumor antigens at the same time. At the DKFZ, for example, research is being carried out on vaccinations for skin cancer and pancreatic cancer. The use of special viruses for cancer therapy, especially in glioblastoma, a type of brain tumor, and the combination of radiation and immunotherapy are also the subject of research in Heidelberg and other DKTK locations.

In addition, basic research into the immune system is of immense importance, as this is the only way to develop completely new approaches to immunotherapy procedures. At the DKFZ, for example, research is being carried out into the functioning of natural killer cells (NK cells), which can destroy tumor cells and convey large amounts of inflammatory messenger substances.

Effectiveness and safety of immunotherapies

In the future, the effectiveness and, in particular, the safety of the use of immunotherapies must be better researched. The danger of a strong activation of the immune system lies in the fact that the immune cells can also direct themselves against the own body. The consequences are autoimmune reactions such as skin rashes, but also different degrees of inflammation of the thyroid, liver, lungs or intestines, which can be life-threatening for the patient.

As studies have shown, the use of checkpoint inhibitors can achieve great success in various types of cancer, but only a small proportion (approx. 20-30 percent across different entities) of patients respond to these therapies. Little is known about why immunotherapies work in some patients and not in others. The new immunodiagnostic platform at the NCT therefore aims to identify biomarkers that predict the response of an individual tumor to immunotherapy, so that ineffective and very risky treatments can be avoided.

Research challenges

The challenges of the coming years lie in the development of biomarkers, in risk assessment to avoid serious complications and in the research of novel immunotherapies. The aim is to develop an effective and specific immunotherapy tailored to individual patients. At the moment, findings from larger studies are used to make therapy decisions in individual patients.

The BMBF-funded DKFZ, NCT and DKTK institutions will continue to do top-class and innovative research in these areas and thus significantly advance the further development of immunotherapy methods for the treatment of cancer.