An Interview with PLOS ONE Editorial Board Member, Professor Tara Mastren

As we launch our curated collection of Radiochemistry research we chat with Dr. Tara Mastren about her work in nuclear medicine, life as an Early Career Researcher, and Open Science.

Dr. Tara Mastren is an Assistant Professor in the Nuclear Engineering Program at the University of Utah. She obtained her PhD in Nuclear and Radiochemistry at Washington University in St. Louis in December 2014. She then worked in the Radiology Department at the University of Texas Southwestern Medical School as a postdoctoral researcher. In May 2016 she joined Los Alamos National Laboratory, for her second postdoc, in their Isotope Production Program. Dr. Mastren’s interests are focused on the production and use of radionuclides for the targeted treatment of cancer and other diseases.

Radioisotopes are utilized in a vast array of research fields. Do you think the breadth of the applications affects advances/progress in analytical techniques using these elements? Is there opportunity for interdisciplinarity amongst the various radiochemistry-related fields? 

TM: Yes, I believe as the field of radiochemistry and its techniques become more well known more researchers will see the advantage of using radionuclides in their research. There is a lot of opportunity for interdisciplinary research amongst the various radiochemistry-related fields. For instance, radiochemical separations overlap a multitude of fields including medicine, forensics, and fuel reprocessing.

How did you become interested in nuclear and radiochemistry?  

TM: Like many I was not exposed to nuclear and radiochemistry in high school or during my undergraduate study. When I attended graduate school, my original plan was to study biochemistry.  One day, however, I attended a professor’s lecture on nuclear reactions in stars and I was intrigued. I went to speak to him about research and he discussed with me a possible opportunity to apply nuclear research to medicine and I got excited about it. I have been a radiochemist ever since.

For many researchers, the use of radionuclides, especially alpha-emitters, demands a high level of meticulous care. Does your field require this level of fastidiousness and what if any precautions do you take in working with these materials? 

TM: Yes, working with radioactivity is a huge responsibility. We undergo lots of training to work with these materials plus have the appropriate radiation detection and dosimetry in place to make sure we are working safely. Work with radionuclides is highly regulated, requires a lot of training, internal safety audits and regulation at the state and/or national level. 

Your own research focuses largely on the new and emerging field of Targeted Alpha Therapy. Can you explain what this is, how it utilizes radionuclides, and what potential it has as an effective cancer treatment? 

TM: Targeted alpha therapy (TAT) has been of interest to nuclear medicine for decades; however, its popularity has grown significantly in recent years as a methodology of interest for cancer therapy. In TAT a highly energized alpha particle emitted during decay is used to induce cell death in cancer cells. An alpha particle is a fully ionized helium atom that is emitted from the nucleus during decay. These alpha particles travel ~10 cell lengths; depositing their energy and destroying the cells throughout their path. The alpha emitting radionuclide can be attached to a biological molecule that acts as a mailman delivering the radioactivity directly to the cancer sites, which maximizes the dose to cancer cells while minimizing the impact to healthy tissues. TAT has shown great promise in cancer therapy – in a study by Kratochwil and colleagues in the Journal of Nuclear Medicine¹ patients with stage 4 prostate cancer have gone into remission after several treatments with TAT. These results have caused a lot of excitement in the field and jumpstarted additional research for the use of TAT in other cancer types.

Can you tell us about any new and exciting projects you’re working on? What do you foresee as the next step in your research journey? 

TM: I am working on projects that involve using nanoparticles for the advancement of TAT. One project is aimed at containing the daughter radionuclides at the cancer site to increase cancer cell killing effectiveness. Several of the alpha emitting radionuclides of interest to nuclear medicine have a cascade of alpha emissions. Each alpha emission results in the formation of a new “daughter” radionuclide. As alpha decay is high in energy, the daughter recoils, traveling ~100nm. This can cause the daughter to be released from the cancer site, increasing the dose to healthy tissues. Encompassing the radionuclides in a nanoparticle can help to mitigate this issue. We have successfully made nanoparticles containing alpha emitting radionuclides, and our next step will be to study them in vitro for their stability and cancer killing abilities.

What are the biggest challenges you currently face as an Early Career Researcher? 

TM: One of my biggest challenges as an Early Career Researcher is learning time and management skills. We aren’t really taught to manage people during our education and becoming an Assistant Professor one of the biggest parts of your job is managing graduate students and postdocs. Additionally, you wear many hats; instructing classes, mentoring students on research, writing grants, creating and using budgets, internal and external service, and making sure all research is conducted safely. It’s a big job that no one prepared you for, but it is also so very rewarding when you observe the progress that is being made as you watch your students evolve into independent scientists.

What are your thoughts on Open Science, and in what ways has your research community embraced this philosophy? (e.g., publishing in open access journals, making data available in public repositories, etc.). 

TM: I think that Open Science is the future of publishing. It grants access to information to students and countries that otherwise would not have access. I believe that increasing access to science and research is important for the betterment of society. As a graduate student and post doc, my advisors embraced open access journals and several of my publications have been in these journals. I also see more and more of my colleagues publishing in these journals. I believe as these journals become more popular more scientists will feel comfortable publishing open access.

¹Kratochwil et al., ²²⁵Ac-PSMA-617 for PSMA targeting alpha-radiation therapy of patients with metastatic castration-resistant prostate cancer, Journal of Nuclear Medicine, 2016.