2026 Talented 12: Euna Yoo

It’s easy to think of proteases—the enzymes that break down proteins into amino acids—as paper shredders: turn them on, feed them a protein to degrade, on to the next. But Euna Yoo thinks there’s more to these enzymes than simple slicing and dicing.

Because protein degradation is irreversible, the process has to be carefully orchestrated, Yoo says. “There are multiple mechanisms to track and keep those activities in check. It’s a rather complicated and intertwined and complex system.”

Yoo’s laboratory group at the US National Cancer Institute (NCI) seeks to understand just how proteases work at the fundamental level. Protease research in oncology often focuses on these enzymes’ role in cancer metastasis, but Yoo investigates how the body’s immune response to cancer activates proteases in immune cells and cancer cells. Her lab develops tools to visualize these processes with the goal of developing better cancer therapeutics.

“There’s a space in chemical biology where if you have the right tool, you can ask all these questions that no one else can ask,” says Matthew Bogyo, a chemical biologist at Stanford University who supervised Yoo’s postdoctoral work. Yoo, he says, has found areas of biology where she can apply her expertise as a chemist “to create a tool that allows you to now ask and answer questions that weren’t previously answerable.”

Her group’s most recent publication detailed a fluorescence-based probe that can measure and visualize the activity of granzyme B—a protease that targets and destroys cancer cells. The probe could track how tumors respond to immunotherapy.

Yoo’s desire to understand the fundamental processes behind complex biology has been a theme throughout her career. She completed her undergraduate and master’s degrees at Ewha Womans University, where she studied pharmacology and medicinal chemistry.

But she wanted to expand her horizons, so she looked at PhD programs in the US and decided on the University of Kansas. “I wanted to be out of my comfort zone,” she says.

Yoo knew that the pace of life in Kansas would be very different from the hustle and bustle of Seoul, where “you can basically have everything that you need with every single moment. But I learned in Kansas how to be patient,” she says.

After earning her PhD, she began her work targeting proteases as a postdoctoral scholar in Bogyo’s lab. This research was quite different from her PhD work studying vaccine adjuvants; in this case, she was developing inhibitors of proteases from the parasite that causes malaria. Bogyo says Yoo was keen to develop new skills, which made her a good addition to the lab. Sure enough, she had made herself at home in the chemical biology landscape by the time she finished her postdoc.

She once again found herself at a crossroads of staying in the US or going back to Korea. “I personally thought at the time that securing an academic position in the US would be more challenging and more difficult. But because of that, I wanted to try that first,” she says.

Yoo was selected for a tenure-track position at NCI’s Chemical Biology Laboratory in the fall of 2019. She’s still developing protease-tracking tools at NCI, but she has shifted her focus away from malaria and into cancer. She’s also begun mentoring students of her own; she leads a team of four people: two postdoctoral researchers and two postbaccalaureate fellows.

She’s now working on exploring proteases as possible biomarkers for immune activity around tumors and examining their upregulation in the tumor microenvironment to find possible therapeutic targets. Yoo says she is particularly eager to see what her tools can help other scientists achieve. “I want to see the initial tools and probes that my lab has developed getting used in the field and the clinical setting by other people.”