Researchers at the Francis Crick Institute in London have designed a vaccine to treat and prevent cancer of the lung, intestine and pancreas, the first laboratory tests of which in mice have shown promise.
The researchers plan to present the results of this trial next Sunday at the 32nd EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics, which had to be held in Barcelona and will be held virtually due to the pandemic this weekend.
The vaccine has been created to target a gene called KRAS, which is linked to the development of many types of cancer, including those of the lung, intestine and pancreas.
The vaccine study has been carried out by Dr. Rachel Ambler, a postdoctoral researcher, and other researchers at the Francis Crick Institute in London. “We know that if the KRAS gene fails, it allows cells to start multiplying and becoming cancerous. More recently, we have learned that, with the right help, the immune system may be able to slow down this process,” he has advanced Ambler in a statement released by the organization of the congress.
“We wanted to see if we could use this knowledge to create a cancer vaccine that could be used not only to treat cancer, but to provide long-lasting protection against the disease with minimal side effects,” Ambler added.
Researchers have created a set of vaccines that are capable of eliciting an immune response against most of the most common KRAS mutations.
The mouse test
Vaccines are made up of two linked elements, a fragment of the protein made by cancer cells that have the mutated KRAS gene and an antibody that helps the vaccine reach a type of immune system cell called dendritic, which helps immune system to identify and destroy cancer cells, an ability that vaccines can boost.
Researchers have tested the vaccine in mice that already had lung tumors and in mice that were induced to grow tumors. They studied the mice to see if their immune systems responded to the vaccine, and they also looked to see if the tumors shrunk or failed to form.
In mice with tumors, 65% of those treated with the vaccine were still alive 75 days later, compared with 15% of those who had not. In animals treated to induce tumors, 40% of those vaccinated were still tumor free 150 days later, compared to only 5% of those not vaccinated (a mouse). By vaccinating the mice, the researchers found that the appearance of tumors was delayed by an average of 40 days.
Slows the growth of tumors
“When we used the vaccine as a treatment, we saw that it slowed the growth of tumors in mice. And when we used it as a preventive measure, we saw that tumors did not appear for quite a long time and that, in many cases, they never appeared. “Ambler summarized.
Some previous cancer vaccine trials have failed, he says, because they were unable to create a strong enough immune response to find and destroy cancer cells.
“Is investigation it still has a long way to go before it can help prevent and treat cancer in people, but our results suggest that the vaccine design has created a strong response in mice, with very few side effects, “he concluded.