Treat cancer with measles viruses?

Combination of immunotherapy and virotherapy is said to kill cancer cells successfully

In the treatment of cancer physicians put great hope for new approaches of immunotherapy. Here, for example, the combination of immunotherapy with virotherapy based on modified measles viruses is a promising option for whose research Dr. med. Dr. Christine Engeland from the National Center for Tumor Diseases (NCT) in Heidelberg has recently been awarded the Anita and Friedrich Reutner Prize.

The team around Dr. Dr. Christine Engeland is working on a combination of immunotherapy with virotherapy. "Virotherapy exploits the fact that certain viruses infect body cells, multiply and cause them to burst," explain the experts in a press release from Heidelberg University Hospital. In their research, the researchers used measles viruses as they are used for vaccinations. "In the laboratory, we were able to show in mice that our altered measles virus is delaying the growth of colorectal cancer," reports Dr. med. Dr. Engeland.

Activate body's defenses against the cancer

Almost half a million people in Germany are diagnosed with cancer every year. Efficient treatment methods are still in urgent need of care. Immunotherapy offers a very promising approach here. It activates the body's own defense mechanisms against the cancer cells. For example, "so-called checkpoint inhibitors can be used to release certain brakes in the immune system that often prevent immune cells from fighting cancer cells," reports Heidelberg University Hospital.

Viruses can specifically infect cancer cells

It has also been demonstrated that so-called oncolytic viruses such as herpes simplex viruses, vaccinia viruses and other viruses specifically infect cancer cells that carry certain sites for docking on their surface or in which pathways associated with cell growth are altered, the researchers report. When the viruses are released, the cancer cells are destroyed and the immune system is activated.

Combination of different therapeutic approaches

Based on these findings, Dr. Dr. Engeland and colleagues changed measles viruses in their investigations to release brakes in the immune system and specifically kill cancer cells. "We supplement measles viruses with antibodies to various brakes in the immune system," explains the researcher. These viruses were able to specifically infect cancer cells, initiate production of the antibodies in the cells and eventually cause them to burst. The released antibodies thus activate the immune system directly on site, so that it acts against the remaining cancer cells.

Decreased side effects

A key advantage of the method is that the production of antibodies takes place directly in the tumor, which reduces the side effects that often occur in an application throughout the body, reports Heidelberg University Hospital. In the laboratory, scientists have already been able to prove that the altered measles viruses delay the growth of colorectal cancer. Now, current research is about bringing immune cells and cancer cells into direct contact. So far the problem exists "that immune cells often do not find and recognize the malignant cells sufficiently", explains the Dr. med. Dr. Engeland. In order to remedy this, special structures (so-called MV-BiTEs, measles virus encoded bispecific T-cell engagers) have been incorporated into the measles virus, which bind to both cancer cells and immune cells.

First patient trial planned for next year

The measles virus causes these junctions to be channeled directly into the tumor and released where they "link" the cancer cells and immune cells on the spot, Dr. Dr. Engeland and colleagues. Again, they have already proven the effectiveness of the approach in mouse models for skin and colon cancer. Next year, the nationwide first patient study on immuno-virotherapy with altered measles viruses will start at the NCT. Accompanying research work on patient cells and blood samples will monitor the changes in the therapy in the patient, according to the Heidelberg University Hospital. (Fp)