How do cells know when to move?
How a KEYS intern from the Navajo Nation joined University of Arizona researchers studying the signals that help cells heal—and sometimes spread cancer.
Hunter Tallsalt (right), a 2026 KEYS intern from Holbrook High School, and graduate mentor Isaiah Toth (left) worked together on cell migration research in the laboratory of Pascale Charest, associate professor of molecular and cellular biology at the University of Arizona.
Caroline Bartelme, BIO5 Institute
Every day, cells move throughout the human body. Some travel to heal damaged tissue, while others help the immune system fight infection. But when cancer cells hijack those same signals, they can spread to other parts of the body. Pascale Charest and her research team study the molecular signals that guide cell movement, with the goal of revealing how diseases like cancer spread.
This summer, 2026 KEYS intern Hunter Tallsalt from Holbrook High School joined the research team of Charest, associate professor of molecular and cellular biology in the College of Science, to investigate how different signals affect the way cells move and repair damaged tissue.
Working alongside doctoral student and mentor Isaiah Toth, Tallsalt grew breast epithelial cells, treated them with different chemical signals and measured how quickly they migrated to repair a small scratch created by researchers. By comparing how the cells responded, the team hopes to reveal how cells repair damaged tissue and what happens when that process goes wrong.
Graduate mentor Isaiah Toth and Hunter Tallsalt discuss microscope images of breast epithelial cells collected during their research.
Caroline Bartelme, BIO5 Institute
For Tallsalt, who traveled from the Navajo Nation and lived in the University of Arizona dorms during KEYS, the project offered something he couldn't experience at his rural high school.
"My school doesn't receive a lot of funding for scientific education," said Tallsalt. "The students at my school have never fully experienced what it's like to work in a lab."
One of the biggest surprises, Tallsalt said, was how quickly the unfamiliar became familiar. At first, everything felt new, but over time, he found himself relying less on his notes, carrying out experiments more independently and settling into the rhythm of the lab.
Those moments stood out to Toth.
"I like the 'oh' moments when they realize how everything connects," said Toth.
For Charest, a member of the BIO5 Institute, watching students grow more comfortable in the laboratory is one of the most rewarding parts of mentoring.
"At first, it's intimidating," said Charest. "But by the end, they know their way around the lab. They know what to do, and you see their confidence and experimental skills grow."
By the end of the summer, Tallsalt contributed to research investigating how cells move and repair damaged tissue. When he begins his first year at the University of Arizona this fall, he'll already know what it means to be part of a research team.
From left: Graduate mentor Isaiah Toth, Hunter Tallsalt, and faculty mentor Pascale Charest.
Caroline Bartelme, BIO5 Institute