Healthcare (Commonwealth Union) – Derek Urwin has a personal connection to his work as a cancer control researcher. After completing his undergraduate degree in applied mathematics at UCLA, he transitioned to a career as a firefighter. His motivation to pursue a second career in science stemmed from the tragic loss of his brother, Isaac, who succumbed to leukemia at just 33 years old, despite their family having no prior history of cancer. Urwin earned his doctorate while collaborating with Anastassia Alexandrova, a professor of chemistry and biochemistry at UCLA.
Currently, Urwin serves as an adjunct professor of chemistry at UCLA while continuing to work full-time as a firefighter for the Los Angeles County Fire Department. His recent research has provided new insights into the chemical factors linked to cancer risk.
When organic materials are burned, the resulting smoke contains compounds known as polycyclic aromatic hydrocarbons (PAHs). These substances can enter the body through inhalation, ingestion, and skin contact. Since industrial and automotive emissions are common sources, nearly everyone is exposed to these chemicals in everyday life. Researchers of the study highlighted the fact that certain occupations, such as firefighting and coal-tar production, expose workers to higher concentrations of PAHs—professions that are also associated with an elevated cancer risk.
The International Agency for Research on Cancer has classified many PAHs as probable or possible carcinogens, with only one, benzo[a]pyrene (B[a]P), being identified as a known human carcinogen.
In a study published in the Proceedings of the National Academy of Sciences, Urwin, Alexandrova, and UCLA undergraduate Elise Tran discovered that some relatives of B[a]P may pose an even greater cancer risk. Utilizing computer simulations to examine molecular interactions, the researchers analyzed what occurs when each of 15 PAHs binds to a specific site in the DNA helix that is often linked to mutations causing cancer. Compared to B[a]P, six of the PAHs demonstrated a stronger tendency to attach to this mutational hotspot. Furthermore, these six compounds were also more likely to evade detection by a critical DNA repair mechanism.
Beyond providing new insights into the relative toxicity of PAHs, this research may also lead to quicker methods for filtering out harmful chemicals and identifying those that pose the greatest risks to human health. Such discoveries could influence laboratory research, population studies, and public policy initiatives.
“We hope that our strategy can speed up the process of studying these chemicals,” explained Urwin, who is the first author of the study. “Instead of casting a wide net, this could show exactly where we ought to start the process. Efficient, effective, accurate computational studies can even enhance or accelerate the process of developing policy that improves public and occupational health.”
Urwin also holds the role of chief science advisor for the International Association of Fire Fighters and was recently appointed to the California Occupational Safety and Health Standards Board.
“Derek’s work as a firefighter made this research possible,” added the corresponding author Alexandrova, who holds membership from the California NanoSystems Institute at UCLA. “He knows what’s going on in the field very intimately, and that enables us to make the connection to chemistry and the tools that we have. Real-life experience educated us about what to do.”
Urwin’s sharp intuition also played a role. He noted that, based on their structures, some PAHs seemed as though they would fit more securely within the DNA double helix—slotting in like a key in a lock.
The researchers expanded on previous studies, using an advanced algebraic technique to precisely model the atomic interactions of PAHs. They then compared how strongly B[a]P and 14 other PAHs bonded to a DNA sequence mutated in about one-third of all human cancers.
Looking ahead, the team intends to apply their computational approach to additional genetic hotspots associated with cancer, as well as to other PAHs and compounds, including PFAS, also known as “forever chemicals.”
With his dual background in firefighting and science, Urwin also values community-based participatory research. This approach involves the community members in the research process—from formulating questions to designing and carrying out the research, and finally, sharing the findings in a way that resonates with those affected.