There is a delicate balance in living cells between normal growth and development and the runaway growth that is cancer. Kunxin Luo, a cell biologist in Berkeley Lab's Life Sciences Division and at UC Berkeley, has been looking at the ways in which this balance gets tilted in favor of tumor development for epithelial cells, the cells lining the skin, blood vessels, and other organs, which are involved in nearly 90 percent of all human cancers.

"My group's research shows that in epithelial cells, two closely related oncogene protein products, Ski and Sno, directly interact with the protein products of tumor suppressor genes at a common point," says Luo. "This indicates that tumor promoter and suppressor proteins do not act independently as many scientists believe, but instead help regulate one another's function."

Understanding the mechanisms by which a normal cell becomes cancerous is like solving a puzzle, Luo says, and she has always enjoyed solving puzzles.

That she would direct this interest to the sciences was in keeping with a family tradition. Her father is a physicist and her mother a biochemist in China, where Luo was born and raised.

Upon her graduation in 1986 from the University of Science and Technology of China at the age of 20, with a bachelor's degree in biology, Luo was encouraged by her parents to continue her education in the United States. After a semester at Notre Dame, she transferred in the fall of 1987 to UC San Diego, where she would go on to receive her Ph.D in biology in 1992.

"When I was a high school senior in China, biology was considered the best major, and students with the highest exam scores often chose biology by default," she says. "I chose biology because of my own interest, although it was against the wishes of my parents who wanted me to study computer science."

During her graduate studies, Luo's interest in biology began to zero in on the protein signals that regulate vital cell processes. These days she's specifically looking at the signals transmitted by TGF-ß (transforming growth factor-beta), an extracellular protein that controls the growth and differentiation of epithelial cells.

"TGF-ß is a very potent protein that affects many aspects of cell function, including tumor suppression, wound healing and embryonic development," Luo says. "I want to understand how the signals initiated by TGF-ß become inactivated in many human cancer cells."

Being a research scientist is very demanding, Luo says, with twelve-hour days in the lab not unusual.

"Biomedical research does not necessarily require genius, but it does require persistence," she says.

Such persistence can be hard on personal relationships, but Luo's husband, Qiang Zhou, understands. He too is a UC Berkeley scientist, studying the molecular mechanisms behind the expression of the HIV gene.

More about Kunxin Luo's research