New biomarkers can predict cancer immunotherapy success
According to health experts, around half a million people in Germany contract cancer each year. After diagnosis, many of those affected are operated on and receive chemotherapy and / or radiation. Immunotherapy for cancer has also been available for some years. A blood test can now be used to predict whether patients will respond positively.
Therapy success can be predicted by new biomarkers
More and more people are getting cancer. According to the World Cancer Report by the International Agency for Research on Cancer (IARC), 20 million new cases of cancer could occur worldwide by 2025. In Germany, the number of new diagnoses has almost doubled since 1970. After cancer is diagnosed, surgery, radiation and / or chemotherapy often follow. For some years now, doctors have also been relying on immunotherapy for cancer. Scientists from Switzerland report that the success of this treatment method can be predicted by new biomarkers.
There have been sensational successes in cancer immunotherapy in recent years.
For example, doctors from London's Great Ormond Street Hospital (GOSH) reported about a little girl who was cured for the first time with a special cell therapy that had never been used before.
And promising results have been achieved in various countries with a new immunotherapy for blood cancer.
However, such treatments do not work the same for all patients. However, the University of Zurich (UZH) is now reporting that it can already be demonstrated in the blood whether cancer patients will respond positively to immunotherapy.
Researchers at the university have therefore identified corresponding biomarkers. Patients who do not benefit from the therapy can be treated early with other methods.
Certain forms of cancer can be successfully combated
Black skin cancer (melanoma) and lung cancer can already be successfully combated with immunotherapy.
The normal function of the immune system, which regularly checks all tissues in the body for pathogens and disorders, is used in a targeted manner: With specific inhibitors, the immune cells are activated in such a way that they detect and eliminate the cancer cells as foreign bodies.
The system can strengthen its often weakening immune response so that even pronounced daughter ulcers (metastases) are found and destroyed.
Cancer can be controlled in this way in up to 50 percent of patients, and some are even cured.
Not everyone responds to therapy
However, about half of cancer patients do not respond to immunotherapy, but must accept the side effects.
A team of researchers from the University of Zurich and the University Hospital Zurich has now used a novel method to find out which patients are likely to respond positively to immunotherapy.
They were able to identify the biomarkers in the blood samples which, before the start of treatment, indicate whether the therapy is more likely to be effective or not.
The experts report on their new findings in the "Nature Medicine" magazine.
“When deciding on immunotherapy, the white blood cells should be analyzed for these biomarkers. This can dramatically increase the proportion of patients who benefit from the therapy, ”says Prof. Burkhard Becher from the Institute for Experimental Immunology at UZH.
"On the other hand, the other patients can use other methods straight away - without losing valuable time with an immunotherapy that is ineffective for them."
High-dimensional cell analysis
In cooperation with the USZ Dermatology Clinic, the researchers examined 40 blood samples from 20 patients before and 12 weeks after immunotherapy for biomarkers.
The high-dimensional cell analysis method Cytometry-by-time-of-flight (CyTOF) was used, which analyzes each cell individually for up to 50 different proteins.
In this way, each individual cell could be identified and its activation status documented. Even nuanced differences between patient samples were recorded precisely.
Recognize molecular patterns
After analyzing the cells, the data were analyzed together with employees from the Swiss Institute for Bioinformatics at UZH for molecular patterns that can predict therapeutic success.
“Even before the start of therapy, we found a subtle and weak immune response in the blood caused by the cancer. We identified this molecular pattern as a small subset of white blood cells (CD14 + CD16 − HLA-DRhi) that indicate better therapy results, ”said Becher.
In order for the finding to be easy to understand, the biomarkers should also be easily detectable in the usual clinical laboratories: In fact, such a blood picture was reproduced in a second, independent cohort of more than 30 people using conventional methods.
Start of precision medicine
"Together with a comprehensive, precisely structured biobanking, this study is an important step towards precision medicine," says Prof. Mitch Levesque from the USZ Dermatology Clinic.
This is also supported by the University's research focus on translational cancer research at UZH. The knowledge gained must now be used in independent studies with larger numbers of patients before they can be implemented clinically.
The method with the help of biobanking, high-dimensional cytometry and computer-aided pattern recognition should also help with other clinical pictures, to make therapy decisions and to develop new therapy approaches. (ad)