Metal chemotherapy can potentiate immune therapies for cancer

Metal-containing chemotherapies enhance immune response to cancer

So far, damage to the immune system has been associated with metal-containing chemotherapy. Researchers have now found that metal chemotherapy can even enhance the immune response to cancer and thus immune therapies.

Number of cancers is increasing

More and more people are getting cancer. According to the World Cancer Report of the International Agency for Research on Cancer (IARC), there could be 20 million new cases of cancer annually worldwide by 2025. In Germany, the number of new diagnoses has almost doubled since 1970. After the diagnosis cancer often follow surgery, radiation and / or chemotherapy. For several years, doctors have also been using immunotherapy for cancer. As researchers have now discovered, this treatment can be enhanced by metal-containing chemotherapy.

Researchers were able to show that chemotherapies containing metal can enhance the immune response to cancer and thus immune therapies. (Image: psdesign1 / fotolia.com)

So far, damage to the immune system has been assumed

Due to their strong tumor killing effect, metal-containing chemotherapies are often used in cancer therapy.

Because of the cytotoxic (cell damaging) effect even against dividing healthy cells, so far rather a damage to the immune system has been assumed.

However, the research cluster "Translational Cancer Therapy Research", set up by the University of Vienna together with the Medical University (MedUni) Vienna, now reveals the opposite in a scientific review article.

As stated in a statement from the universities, metal chemotherapy may even increase the immune response to cancer and thus immune therapies.

This partly because they make the cancer cells "more visible" and eliminate inhibitory immune components.

The article by the researchers appeared in the journal "Chemical Reviews".

More than 1,300 scientific articles illuminated

According to the study, the inter-university research cluster "Translational Cancer Therapy Research" reviews all papers (more than 1,300 scientific articles in total) that deal with the interaction between the immune system and metal-based chemotherapies.

In addition to publications of the past 30 years, main author Walter Berger of the MedUni Vienna and his colleagues also discuss new aspects and compile a comprehensive inventory.

"The result clearly shows that the combination of metal-containing chemotherapies and immunotherapies is one of the most promising therapy concepts of the present and the future," says Berger.

Metal chemotherapy also destroys inhibitory components of the immune system

The explanation behind this finding: every cancer is preceded by a long fight of the immune system with the potential cancer cells that the immune system eventually loses.

The reason for this is that the tumor either fails to be generally recognized as foreign or to control and calm the immune cells.

Metal chemotherapies now not only destroy tumor cells, but also prefer the "burnt out" or inhibitory components of the immune system.

In response, the immune system is renewed from stem cells, rejuvenating and reactivating the fight against cancer.

Therefore, metal-containing chemotherapy also increases the effects of immune checkpoint inhibitors.

The reason: tumor cells come from body cells. The immune system is trained to spare the body's own cells, so it is difficult or even impossible for tumor cells to recognize it.

Metal-based chemotherapy now kills the tumor cells, which change in the process of disintegration. This otherness makes them visible and vulnerable to the immune system, a mechanism called "immunogenic cell death".

At the same time, the tumor cells also "try" to escape the effect of the chemotherapeutic agent on the basis of an increased mutation rate. Each of the resulting new mutations, however, has the potential to be better recognized by the rejuvenated immune system.

Thus, chemoresistant tumor cell clones appear to be preferentially attacked by the immune system. (Ad)