Understanding How Radiation Affects our Cells: An Interview with Siamak Haghdoost

Dr. Siamak Haghdoost, Professor of Molecular Radiobiology at University of Caen and University of Stockholm, and Work Package leader in the HARMONIC project, tells us about his work in HARMONIC and shares some personal considerations

Can you explain briefly who you are and what you do?

My name is Siamak Haghdoost. I am a radiation biologist by training, and at the moment I am working at the University of Caen in France but I keep an affiliation with Stockholm University. So, I am representing both universities in HARMONIC.

My research interest revolves on understanding the early and late health effects of radiation; more particularly, understanding how our cells respond to low/high doses of ionizing radiation.

What types of radiation do you look at?

Good question. My previous research covered the so-called non-ionising radiation, basically UV radiation, and also ionising radiation such as X-rays. But since I moved to France four years ago, I have also started looking at particle radiation – or what we call high linear energy transfer (LET) radiation – including proton and carbon ion radiation. Carbon ion radiation is also being used to treat cancers, with the advantage that the dose to the normal tissue is expected to be lower as compared with protons and has high biological effect. Some places in Italy and Germany for example are already using it, and we plan to start soon in Caen.

What is your role in Harmonic?

I am responsible for the radiobiology work package (WP5) in HARMONIC. The aim of this work package is to understand the biological processes that can lead to late health effects in paediatric patients exposed to ionizing radiation. Specifically, we look for four main outcomes: secondary cancers, cardiovascular problems, chronic inflammatory responses and chronic oxidative stress.

How do you study this?

The clinicians involved in HARMONIC are collecting blood and saliva samples from the patients, before and after radiation exposure, including one year after. We will have samples from three groups of patients: those treated with proton therapy, those treated with photon therapy and those undergoing cardiac fluoroscopy. We look at changes induced by exposure to radiation at the levels of proteins, microRNAs and other markers mitochondria numbers, telomere lengths, etc. We always compare with the sample that was taken before the intervention. The sample taken one year after radiation exposure is very important, since we are looking for more stable effects. We hope that these changes can give us information on what’s going on in the body of irradiated young patients.

In a previous conversation, you mentioned that your work package has reached an important milestone. Would you care explaining?   

We have now in Stockholm a biobank to stock blood and saliva samples, and we have just received the first delivery of samples from Italy (complete samples from a dozen of cardiofluoroscopy patients), so, we can soon start with some of the analyses. It’s the starting point for our laboratory work. We’re also waiting to receive samples from the Danish team soon.

By the end of the project, in about two years, we expect to have a good number of analysed samples, enough to even do some statistical analysis.

How will the results of your work package contribute to the well-being of children exposed to medical radiation?

Within the HARMONIC time frame (5 years) it will be difficult to have final results, since the majority of the late health effects will surely take longer than that to appear. But that is why the biomarkers which can be find in the frame of HARMONIC in the samples taken after radiation exposure will be so important – by following these children beyond the project duration, we can retrospectively determine if some of these markers can be used to predict the risk of developing adverse effects later on.

So, the patients included in HARMONIC may not benefit directly from these results, but they will contribute importantly to research that will help future patients.

And, of course, our patients may benefit in the sense that, if we see a clear upregulation of, for example, markers of heart disease in a patient’s sample, we can act accordingly.

And now let’s move to some more personal questions. What did you want to do when you were a kid?

I wanted just to play football and handball! Actually, because of my father, I wanted to do some research in justice. I was very young, 5-6 years old, and I asked if I could join his class. He said that it was for grown-ups but that I could come. It was amazing – I remember sitting there, among adult people, listening to him.

And then, when I was 13-14, just before high school, I realised that my natural science-related subject scores were high, but the other ones were not. So, I decided to go in this direction. And I don’t regret it.

What do you enjoy most about your job?

I enjoy the flexibility, and always having to think, to formulate problems and find a solution. I love the creativity, the feeling of creating new things, new protocols…   And I also like the teaching part, the connection with young students.

And the least?

Having to take the telephone everywhere with me and having to answer emails even in the middle of vacations. I know this is not healthy, but sometimes I have to. I wish I could disconnect more often.

What advice would you give to young researchers in your field?

Radiation biology is quite a narrow field of research, and there is often a lack of resources. My advice is don’t give up when you do not get funding for your project. Remember it is an important area of research that can save lives.

Maybe you, as researchers, can help raise awareness among funders? 

Yes, it has to come from us to actively convince the European Commission that we need to improve the current knowledge on radiation effects, particularly for proton therapy. We need to fill research gaps at different levels- from the basic, cellular level to the long-term clinical follow-up of patients, specially of paediatric patients.