Cristina G. Lucio Madrid


Updated Tuesday, February 27, 2024-18:31

An international reference in the field of Radiology, Yolanda Prezado (Verín, 1977) 'returns home' after developing a large part of her professional career in Paris.

The Galician has just signed up for the Singular Center for Research in Molecular Medicine and Chronic Diseases (CiMUS) of the University of Santiago de Compostela from which she will direct a new line of research in proton therapy.

One of its main objectives is to place Spain at the forefront of this area of ​​research, which is immersed in

"a paradigm shift."

Our country, he assures,

"can become one of the great powers of proton therapy."

"We have a great opportunity ahead of us" with the 13 proton therapy teams that will be available in Spain in the short term, says the researcher, who refers to the two teams that already exist in Madrid and the one tendered in Cantabria, which will be added soon those donated by Amancio Ortega.

The arrival of these new proton centers "will place Spain as one of the countries with the most proton therapy lines per inhabitant", which places it in a privileged situation for the advancement of research.

If this is coordinated well, he says, it will greatly favor studies in this field "and will allow us to know the radiobiology of protons better and better," which will result in an expansion of the locations and effectiveness of this therapy.

"My intention is to help build something relevant. We have to work as a team. If done well, Spain can become one of the great powers of proton therapy.

There is a very important opportunity to place Spain in a pole position 'at the international level

' in the field of radiotherapy in general and proton therapy in particular.

New approaches in Radiotherapy

Prezado founded his team in 2013 at the French National Center for Scientific Research (CNRS) to explore new approaches in Radiotherapy, an objective that he later transferred to the Institut Curie in Paris, from which he now arrives at CiMUS.

At the Galician research center he wants to establish lines of collaboration and synergies with different groups from different disciplines.

"We have been working on these lines of research for many years, developing new approaches. The philosophy is to improve the therapeutic index of Radiotherapy, which is one of the main pillars of cancer treatment."

Radiotherapy, the researcher emphasizes, is today a powerful and sophisticated tool against different tumors.


the potential for improvement in this area is enormous.

We're only seeing the tip of the iceberg

of what this approach can offer, she notes.

Recent research, in fact, suggests a more than promising future with regard to this type of treatment and its clinical usefulness.

For example, he points out, there is increasing evidence that by modifying the physical parameters of irradiation, that is, the way in which we deposit the dose in the body, we can modulate the biological response to cancer, which opens up an extensive field. of action.

mini proton beams

Along these lines, Prezado's team has been a pioneer in the development of new radiotherapy techniques, such as

radiotherapy with mini proton beams

, a strategy that in laboratory studies has proven to be less invasive and more effective.

For this approach, the researcher has received the award from the French Academy of Sciences and the award of a Consolidator Grant from the European Research Council (ERC).

Compared to conventional therapy, standard proton therapy already allows more precise irradiation, largely preserving the healthy tissues surrounding the tumor.

But Prezado's technique, according to what preclinical research suggests, would allow us to go one step further, activate other biological mechanisms against cancer and reach locations and

tumors that were hitherto impregnable.

"It is a technique that drastically reduces the toxicity of healthy tissues and

increases the effectiveness of tumor control

in tumors as aggressive as


," explains the researcher.

In a trial in rats implanted with glioma models, the strategy has demonstrated very important tumor control, with survival rates in the animals of up to 70% tumor-free.

Those experiments were done with very high doses of irradiation, an approach that could not have been carried out with standard proton therapy without causing significant damage to the brain.

In the case of mini proton beams, however, the treatment was safe.

In subsequent behavioral studies in the treated rats, no cognitive or motor damage was observed.

But the researchers also observed another additional advantage of the technique.

Minibeams allow heterogeneous doses of irradiation to be applied, so that part of the tumor receives lower doses of the treatment than other areas.

Prezado's team wanted to test the effects of these differences in an experiment in which, despite the heterogeneity, the survival of the animals remained high.

The scientists then thought about the possibility that the approach was

activating other radiobiological mechanisms.


hypothesized that the key could be in the immune system and set out to continue investigating.

Among the new tests they carried out, they considered injecting tumor cells again into the contralateral hemisphere of several animals that had already been previously treated with the mini proton beams and had been cured.

And what they found is that, while the control animals developed cancer, none of the irradiated animals did.

"A kind of

vaccine effect

was produced , the immune system was capable of recognizing the tumor cells," says Prezado, who clarifies that this discovery could be very interesting to deal with one of the main problems that gliomas present, their high rate. of recurrence.

Researchers are already preparing

clinical trials

to test the usefulness of the technique in patients.

Specifically, they are seeking funding to carry out the first phase of clinical research.

In addition, they are also exploring the combination of the technique with immunotherapy approaches, such as


Other approaches

Another line that Prezado investigates is the so-called

FLASH radiotherapy

, which basically consists of applying high doses of radiation in a very short time,

"in milliseconds instead of giving them in minutes."

They have also carried out preclinical studies with the technique, aimed at reducing toxicity in healthy tissues and organs, although Prezado acknowledges that this approach is much further from reaching the clinic and has yielded some discouraging results.

"It is very interesting at the research level, but I think that many more studies still need to be done to find an optimal configuration and to be able to think about reaching the clinic," says the researcher, who points out that the team also has a line that explores the combination of radiotherapy with nanoparticles.

"We are in a very interesting moment in the field of radiotherapy. In the midst of a

paradigm shift

and established dogmas being discarded, such as that strictly homogeneous doses are needed to eradicate a tumor," says the scientist.

In that sense, Prezado adds that the discipline is changing to be guided by biology instead of technology.

"For example, it has been seen that protons have a greater capacity to inhibit tumor angiogenesis, which is beneficial for tumor control."

So far, we are exploiting the physical advantages of protons.

But the moment we begin to investigate more about the radiobiology of protons, we will be able to treat different tumor locations more effectively and we will be able to

use protons in a much more optimal way

, he advances.

"We are at a key point, at a very important moment in research, where an explosion of innovation and new knowledge is taking place. In the coming years we are going to see great evolution. All this research will undoubtedly improve treatments" .

And there Spain can play a key role, Prezado emphasizes.

The scientist says that she decided to return due to "a mixture of personal and professional considerations" in which, without a doubt, the fact that "right now we have a very important opportunity to place Spain in a very good situation in the international panorama of radiotherapy".

"Due to its professionals, resources, operation and strategic location, CiMUS is the ideal ecosystem to amplify the research in this field that was being developed at the

Institut Curie

in Paris, a research that, due to its transversal nature, will allow it to easily establish synergies with the different groups of this Singular Center. The specialties in biology, medicine and

Drug Discovery

methods of CiMUS are extremely interesting to be applied in the field of radiotherapy."

To this day there are still tumors for which there is no hope and there are still patients who are cured but with significant consequences, he concludes.


We have to continue investing and researching in the field of Radiotherapy.

And I would like to contribute to building something relevant. Contribute all my experience and my contacts to the Spanish scientific community so, together, we can help patients."