Specific microproteins in liver cancer open door to potential vaccine

A team of Spanish scientists has identified a set of microproteins that They are found only in liver tumors. and that they are clearly identified by the immune system, making them an ideal target for the development of cancer vaccines.

Details of the study, carried out by the Research Institute of the Hospital del Mar in collaboration with the Sima de Navarra University (CIMA) and the Pompeu Fabra University, were published in the journal Science Advances.

In the first phase of the study, based on advanced bioinformatics methods, the team identified this set of microproteins from samples from 117 patients With Liver cancer.

“We had tissue from both the tumor and healthy adjacent tissue, so we defined very accurately “These microproteins are found only in the tumor and do not appear in healthy tissue of the same patient, in the liver or other tissues,” explains EFE Mar Alba, an ICREA researcher at the Hospital del Mar Research Institute and author of the study.

These microproteins represent an ideal target for development of a vaccine against cancer because, being expressed only in tumors and not in healthy tissues, they make it possible to create vaccines that activate the immune system’s defenses and specifically attack cells containing these proteins and found only in the tumor.

To confirm these results in the lab, the team studied the immune response to the vaccine in mice and confirmed that the animals’ immune systems could see these microproteins, suggesting that “They have the potential to develop vaccines”emphasizes Alba.

Cancer vaccines

The development of cancer vaccines is based on the ability of the immune system recognize foreign molecules that are not part of the body But some types of cancer, such as liver cancer, are very difficult to detect.

Therefore, for this type of cancer, the discovery of these microproteins represents a very encouraging alternative.

“This study shows that there is significant amount of microproteins which are expressed exclusively in tumor cells and can be used to develop new treatments,” says Marta Espinosa Camarena of the Del Mar Hospital Research Institute and co-author of the study.

“We saw that some of these microproteins can stimulate the immune system. potentially generating a response against cancer cells. This response can be enhanced by vaccines similar to those against coronavirus, but which produce these microproteins. These vaccines can stop or reduce tumor growth,” says Puri Fortes, a scientist at CIMA and CIBERehd.

Additionally, unlike other types of vaccines that rely on patient-specific mutations, this treatment can use on multiple peoplebecause the same microprotein is expressed in several patients.

And although studies on the use of vaccines have not yet begun, researchers believe that Its administration can be relatively simple.“This is our goal,” the authors defend themselves.

The team will conduct testing first. combinations of these microproteins in mice to see how the immune system of mice responds and to see how it works as a vaccine, and if all goes well, the next step will be to test it on human cells to see if lymphocytes are activated.

High quality research

According to Ramon Salazar, head of the medical oncology service at the Catalan Institute of Oncology in L’Hospitalet (ICO), this is a “high-quality” study, combines “all the latest generation technologies to test a new concept that may be clinically very relevant.

“The most important thing is to confirm that there are regions in the genome of these cancer cells that were thought to be silent, but which In fact, they encode microproteins.and the discovery that these proteins are tumor-specific and can stimulate the immune response,” he explains in a statement to the Science Media Center of Spain (SMC Spain).

“So they can be used to produce generic vaccines “on a mass scale, without the need to individualize each patient, which could mean great progress,” he notes.

Regarding possible limitations of the study, he points out that there is still no clinical experience and that while the concept is “very attractive,” one of the problems with hepatocellular carcinoma and other tumors is that “their system for presenting proteins to the immune system is malfunctioningwhat is needed for vaccines to be effective”