COVID vaccinations drive cancer research
The mRNA vaccines were used against the coronavirus SARS-CoV-2 for the first time on a large scale in humans. In fact, research into such vaccines was carried out long before the corona pandemic. The global focus on this topic has given technology in this area a huge boost. This could also result in new cancer vaccines in the foreseeable future. Expert Dr. Guido Wollmann explains the details.
Dr. Guido Wollmann is head of the Christian Doppler Laboratory for Viral Immunotherapy at the Medical University of Innsbruck. His specialty are so-called oncolytic viruses. This special type of virus acts directly or indirectly against tumor cells. For more than a decade, researchers have tried to use such viruses to treat or prevent cancer. The knowledge gained from the corona vaccines could now bring the decisive breakthrough.
Expert interview with cancer researcher Guido Wollmann
Although the big breakthrough has not materialized so far, the results of decades of research into cancer vaccines have helped ensure that the mRNA vaccines against SARS-CoV-2 can be launched so quickly. Cancer researcher Wollmann explains why cancer research is now benefiting from the findings from corona mass vaccinations.
What is the status of mRNA vaccines against cancer?
“The three well-known mRNA vaccine manufacturers have a very strong background in cancer vaccination that has grown over the years,” reports Wollmann. One reason why the corona vaccine development went so extremely quickly is largely that these vaccine technologies are already well advanced in cancer therapy. According to Wollmann, these RNA platforms, which can then be individually equipped with RNA snippets of the coronavirus or tumor mutations, have been very well characterized in clinical studies in thousands of cancer patients for many years.
How do the principles of action differ in cancer and corona?
“In an mRNA vaccine you put very short-lived genetic information and your own body cell uses it to produce a protein,” explains the expert. This could, for example, be the information of a viral protein, but also that of a modified component of an endogenous protein, namely that of a tumor mutation. An mRNA vaccine could therefore specifically code the areas of a mutation against cancer. “These are tumor components that are only perceived by the immune system, but no longer have any function themselves,” emphasizes the laboratory manager.
Inject oncolytic viruses into the tumor
In addition to the mRNA vaccines, there are also so-called vector vaccines against SARS-CoV-2, the principle of which is different. “For use in the COVID vaccination, certain viruses are almost completely gutted, filled with a small part of the genetic information of the COVID virus – here as a piece of DNA instead of RNA – and used as a ferry,” explains Wollmann. The body still recognizes the enucleated virus as a virus and generates an immune response.
“It is different with oncolytic, cancer-killing viruses,” says the cancer researcher. They could not be gutted because they should only multiply in the tumor. In cancer research, therapies are currently being developed in which oncolytic viruses are injected directly into the tumor. There they specifically attack the cancer cells and also trigger inflammation, which makes the immune system aware of the tumor.
Will the COVID vaccines advance cancer research?
“Yes, very well,” emphasizes Wollmann. According to the expert, all the very important, but also strict, regulatory processes represent a major burden for the large companies in the process of clinical test phases and approval. It helps if one draws on the experience of millions of applications of these novel biological therapy platforms can.
“Now you have additional arguments with regard to the security profiles,” explains Wollmann. This mass vaccination alleviates many of the concerns about these novel therapies. The corona pandemic also created a major lead in the upscaling process, i.e. when upgrading the operating facilities to produce large quantities of vaccine. This is an important future bonus for cancer vaccine development.
How does cancer research benefit on a technical level?
“Research on vector-based cancer therapies – i.e. both cancer vaccines and oncolytic viruses – can learn in particular from the immunological interactions between the immune reaction against the target antigen, i.e. the corona or tumor protein, and the anti-vector immune response”, so Wollmann.
“Another related and very topical topic would be the now intensively investigated use of COVID mixed vaccinations,” the expert continues. This principle has been pursued in experimental cancer therapy for over ten years, and the ongoing studies on this approach around the world would certainly also encourage the mixed use of cancer vaccines. You get clinical data on the body’s reaction to the vaccine combinations and you can draw parallels.
How does the immune system react to adenoviruses?
Adenoviruses are used for COVID-19 vector vaccines, which are also used for oncolytic viruses. “Everyone is constantly exposed to adenoviruses – these are the classic, mild cold viruses,” explains the scientist. The adenovirus generates very strong, but not long-term immunity. However, there are many adenovirus subspecies. The four adenovirus-based COVID vector vaccines currently approved in different parts of the world are based in part on different adenovirus subtypes that occur very rarely or not at all in humans. In this way, an already existing immunity is circumvented.
“In tumor therapy it has been shown that the intravenous administration of oncolytic adenoviruses only very rarely leads to the desired reactions in the tumor tissue, which is largely due to this certain pre-immunity against certain adenoviruses,” explains the expert. Due to the high probability of existing immunity, according to Wollmann, oncolytic adenoviruses as well as other oncolytic human viruses are injected directly into the tumor.
What are the side effects of a cancer vaccination?
“In general, compared to chemotherapy, the side effect profile of cancer vaccines or oncolytic viruses is much lower,” emphasizes Wollmann. You have treatment reactions that are part of the immune response that is triggered in the body. These are mostly flu-like symptoms.
“With RNA applications, they are generally considered to be very safe,” says Wollmann. The extremely rarely described, strong allergic reactions can be ascribed to the nanoparticle shell, the protective bubble in which the RNA is located. After closer examination of these cases, it turned out that this particular allergic reaction only affects those people who have had an allergic history to a component of these nanoparticles, namely the stabilizer polyethylene glycol (PEG). “Those affected already showed antibodies against this component,” explains Wollmann. If PEG is injected with the vaccination, it could lead to an allergic reaction.
Are there approved viral tumor therapies?
“A milestone was reached in 2015 when the first oncolytic virus was approved for the treatment of black skin cancer in the USA and Europe,” says Wollmann. The “T-Vec”, based on a modified herpes virus, brings very good treatment results for a certain number of those affected. The response rate is roughly in the range in which the so-called checkpoint inhibitors (immunotherapy form, note) have revolutionized cancer therapy.
“In many cases, responding not only means prolonging survival, but also long-term control of the tumor right through to healing,” emphasizes the cancer researcher. On the one hand, the viruses infect the cancer cells in the treated tumors in a highly specific manner and destroy them. On the other hand, the viruses also trigger a very strong immune response against the tumor and thus prevent it from returning to other parts of the body, i.e. the formation of metastases.
“That is the great promise of these oncolytic viruses”, sums up the head of the Christian Doppler Laboratory for Viral Immunotherapy. Almost all clinical studies on oncolytic viruses are now combined with immunotherapy. (vb)
Author and source information
This text complies with the requirements of specialist medical literature, medical guidelines and current studies and has been checked by medical professionals.
Diploma-Editor (FH) Volker Blasek
- Innsbruck Medical University: “The COVID vaccination advances cancer research” (published: 16.06.2021), i-med.ac.at
- Federal Center for Health Education (BZgA): All important information on mRNA vaccines (as of: May 28, 2021), infektionsschutz.de
- Christian Doppler Forschungsgesellschaft (CDG): CD Laboratory for Viral Immunotherapy of Cancer (accessed: June 18, 2021), cdg.ac.at
This article is for general guidance only and is not intended to be used for self-diagnosis or self-treatment. He can not substitute a visit at the doctor.