Helps mice…
Activating the immune system against cancer cells or developing a vaccine to prevent cancer are promising strategies, especially if they can be implemented with minimal side effects. However, previous trials of cancer vaccines have not been successful because they have failed to elicit a sufficiently persistent and strong immune system response to destroy cancer cells.
A new experimental vaccine that activates the body's own immune system to target cancer cells has proven effective for the treatment and prevention of cancer in mice. It was created to target the KRAS gene, which is known to be involved in the development of many cancers, including lung, bowel and pancreatic cancers. Researchers have also found a new way to detect and treat aggressive forms of lung cancer that are able to evade the attack of the body's immune system.
Both studies were presented at the 32nd Symposium of the European Organization for Research and Treatment of Cancer (EORTC-NCI-AACR), which was held online.
Scientists have long known that the KRAS gene does not work (or mutates) in many types of cancer, still trying to find a way to turn this knowledge into an effective treatment.
The study of the new vaccine was conducted by Dr. Rachel Ambler and her colleagues from the Francis Crick Institute, UK.
They decided to create an anti-cancer vaccine that could not only treat, but also provide long-term protection against cancer with minimal side effects.
Dr. Ambler and her colleagues have created a set of vaccines that can stimulate the immune response to the most common KRAS mutations. Vaccines consist of two elements connected together. One element is a fragment of a protein produced by cancer cells with a mutated KRAS gene. Another element is an antibody that helps deliver the vaccine to dendritic cells. It is these cells that play a key role in helping the immune system detect and destroy cancer cells.
The group tested the vaccine on mice that had already developed lung tumors, and on mice whose tumors were just forming. The researchers studied mice to see how their immune system responds to the vaccine and what happens to tumors.
65% of the animals among mice with tumors who received the vaccine were alive after 75 days, compared with 15% of mice who were not injected with the vaccine.
In mice treated during tumor induction, 40% of vaccinated animals remained healthy after 150 days compared to 5% of unvaccinated mice. After vaccinating the mice, the researchers found that the appearance of tumors is delayed by an average of about 40 days.
Researchers from the same group have also made an important discovery about how lung cancer can evade the body's immune system and complicate treatment. In patients, they found that the activity of the KRAS gene leads to the accumulation of adenosine. Higher levels of adenosine are known to weaken the body's immune response, preventing immune cells from targeting and destroying cancer cells.
The researchers then studied lung cancers with similar KRAS activity in mice to see if adenosine levels could be manipulated to increase the effectiveness of treatment. By injecting mice with the AstraZeneca-produced drug, oleklumab, designed to reduce adenosine levels, along with existing anti-cancer drugs that help the immune system fight cancer, the researchers found that survival improved.
These results give hope that one day it will be possible to use a combination of drugs to support the immune system and successfully treat patients with an aggressive type of lung cancer.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on EurekAlert: Vaccine to treat and prevent lung, bowel and pancreatic cancer shows promise in the lab.