Advancing neuroblastoma research: Insights from a PhD stay at the University of Tokyo

Ioanna Tsea is a doctoral student in the Department of Women and Children’s Health, Division of Pediatric Oncology and Pediatric Surgery, at the research group of Associate Professor John Inge Johnsen. She recently visited the University of Tokyo as part of the collaboration between KI and UTokyo.

What is your area of research?

My doctoral research focuses on Neuroblastoma, one of the most aggressive cancers in young children. More specifically, our main goal is to understand the different types of cancer cells that make up Neuroblastoma tumours and how these cells interact with their surroundings. To this end, we utilise single-cell and spatial omics technologies, which allow us to look at each cell in a tumour in unprecedented detail. As we discover more information about the different types of cancer cells that make up Neuroblastoma tumours, we can uncover new targets for treatment and help develop more personalised therapies for children with cancer.

Why I chose The University of Tokyo?

I chose the University of Tokyo because it’s one of the world’s leading research universities, especially in the field of biomedical science and cancer research. What truly impressed me about the University of Tokyo is its commitment to pushing the boundaries of cancer research through cutting-edge technology. The university is a global leader in developing and applying advanced imaging methods, many of which are not currently available at Karolinska Institutet or Sweden. These powerful techniques allow scientists to observe how proteins behave inside individual cancer cells, offering a deeper understanding of how cancer develops and spreads. The University of Tokyo is an ideal environment for learning these advanced methods and expanding my expertise in Neuroblastoma research. 

Beyond the lab, the University of Tokyo offers a vibrant and intellectually stimulating environment. It has a strong culture of interdisciplinary collaboration, world-class facilities, and a deep commitment to pushing the boundaries of science. For me, it was the ideal place to grow as a researcher, gain new skills, and contribute to meaningful discoveries in pediatric cancer.

What did you do during your lab visit at the University of Tokyo?

During my 5-week research visit at the Institute of Quantitative Biosciences at the University of Tokyo, I worked in Associate Professor Donald Cameron’s lab, which specializes in advanced imaging techniques to study how cancer cells behave. My main focus was learning and optimising a tool called mass photometry, using the Refeyn Two system. This technology helps measure how proteins interact and form larger structures, something that’s key to understanding how cancer grows.

We tested several cancer-related proteins, including ones linked to Neuroblastoma, under different lab conditions, like temperature and salt levels. This helped us figure out the best way to use the instrument and get reliable results. By the end of the visit, we had created a Standard Operating Protocol (SOP) for the system and trained a postdoc in the lab to use it independently.

This experience gave me valuable technical skills and added a new layer to my research. Now, I can study cancer-related proteins not just at the genetic level, but also at the protein level, which will help our research towards understanding how Neuroblastoma develops and spreads. 

What were the major differences between working in a lab KI and The University of Tokyo?

Working at the University of Tokyo was a fascinating and enriching experience. One of the biggest differences from my time at KI was the cultural environment. In Japan, there is a strong sense of hierarchy and respect, both inside and outside the lab. People are very mindful of how they interact with others, and formal communication is the norm. This structure creates a very organised and disciplined atmosphere, which noticeably boosted my productivity. The clear expectations, respect for roles, and daily routines helped me stay focused and efficient throughout my research visit.

Another standout aspect was the work ethic. Japanese researchers take great pride in their work and approach each task with care and diligence. Every day, I saw how committed they were to precision and quality, which motivated me to be even more detail-oriented in my own research.

In terms of lab structure, KI tends to have a more open and collaborative setup, where different groups share space and ideas freely. At UTokyo, labs are more compartmentalised, but the equipment is state-of-the-art and meticulously maintained. Access to advanced technologies was a major advantage and allowed me to explore techniques not yet available in Sweden.

Even the rhythm of the workday felt different during my time at KI and UTokyo. At KI, we often take breaks together, like the Swedish “fika,” which fosters a relaxed and social atmosphere. In Japan, breaks are more individual, and the focus remains on maintaining a steady workflow throughout the day.

Overall, the experience at UTokyo gave me a new appreciation for structure, discipline, and dedication in research. It broadened my perspective and enriched my approach to science in ways I’ll carry forward in my career.

What is your impression of Tokyo?

My impression of Tokyo is that it’s a city full of contrasts and character. It is a place where modern ideals and deep-rooted tradition exist side by side in a way that feels both natural and captivating. I was truly fascinated by how seamlessly the old and the new coexist in the city of Tokyo. You can stroll past ancient temples and shrines, then turn a corner and find yourself surrounded by modern skyscrapers, high-tech stores, and digital billboards. This intriguing “marriage” of eras gives Tokyo a unique energy that’s unlike any other city I’ve visited.

Tokyo is also incredibly diverse and vast, with each neighbourhood offering its own distinct personality. I loved exploring areas like Asakusa, with its traditional atmosphere and historic Senso-ji Temple, and Shibuya, which is lively, bright, and full of energy. Harajuku stood out for its creative fashion and youth culture, while Ginza offered a more refined and elegant experience. Even quieter neighbourhoods like Shimokitazawa had their own charm, with cosy cafés and vintage shops that made every walk feel like a discovery.

And of course, the food was unforgettable. I spent a lot of time trying different dishes from Japanese cuisine and enjoyed the rich tea culture. Even the simplest meals were beautifully prepared and full of flavour.

Overall, Tokyo for me is a city that invites you to explore, learn, and experience and I feel incredibly fortunate to have visited it. 

Do you have any recommendations?

I had the advantage of knowing Japanese before my visit, which allowed me to engage more fully with everyday life and better understand the depth of Japanese culture and values. Speaking the language helped me connect more easily with colleagues and appreciate the subtle aspects of communication, respect, and social harmony that are central to Japanese society. While it’s certainly possible to get by with English, especially in Tokyo’s academic and international settings, I would strongly encourage future doctoral students and researchers to familiarise themselves with both the language and cultural norms. Even a basic understanding can enrich the experience, help with daily interactions, and offer a deeper appreciation of the environment you're working in.

A memorable experience from your stay 

Mount Fuji is one of the most famous and meaningful symbols of Japanese culture. It’s often shown in art and history, but seeing it in real life is something else entirely. Because the mountain is usually covered by clouds, it’s actually quite rare to get a clear view of the whole peak. That’s why my trip to Lake Kawaguchi was so special, because I was lucky enough to visit on a clear day and see Mount Fuji in full, from base to summit. The view of Mount Fuji was absolutely stunning and it felt like a perfect moment, quiet, beautiful, and deeply connected to the spirit of Japan. It’s one of those experiences I’ll never forget.

To what extent have your stay abroad affected you personally?

During my time in Japan, I was deeply moved by the respectful culture. From how people greet each other to how they behave in public spaces, there’s a strong sense of consideration and harmony. It made me reflect on how I interact with others and helped me grow personally, not just professionally. People seemed to work with intention and care in how they approached even the smallest tasks, a mindset that really stayed with me and has allowed me to reflect upon my habits. 

What will you bring back to KI?

My time at the University of Tokyo gave me so much to bring back to KI, both in terms of research and personal growth. One of the biggest contributions is the technical expertise I gained while working with the Refeyn Two mass photometry platform. During my stay, we successfully optimised the system and developed a Standard Operating Protocol (SOP), which now allows for precise and efficient measurement of protein complexes using very small sample amounts. This new skillset adds a whole layer to my PhD work, allowing me to compare protein-level findings with what we already know from DNA and RNA analysis. It thus offers a more complete picture of how these oncoproteins behave and contribute to cancer progression. I’m excited to apply this knowledge back at KI and continue building on it.

But just as importantly, I’m bringing back a renewed sense of focus, structure, and appreciation for detail—values I saw every day in the Japanese research environment. These experiences have shaped how I approach my work and will continue to influence how I contribute to the research culture at Karolinska.