Davidson College summer research student Itzy Cuellar '20 is attacking cancer where it spreads: how cancer cells communicate. Her results will help propel the search for potentially life-saving, carbohydrate-based cancer drugs.
Sugar is a carbohydrate and a key to how cancer cells interact with healthy cells when they spread to other parts of the body.
Cuellar said to think of the telephone you made as a child, with two cans and a string.
"The can is the arm of the cell. The string is the sugar. In order for cells to communicate with one another, two cells have to be holding onto that string. We're looking at ways to give a cancer cell a string that's not attached to a healthy cell."
If the cancer cell's arm is holding a string with nothing on the other end, the cancer cell cannot invade healthy tissue. No communication, no cancer spread.
The same principle of carbohydrate binding could be used to attach that empty, other end of the "string" to an anti-cancer drug.
Cuellar's experiments focus on finding the most efficient ways to produce glycogenin, a human enzyme that builds glycogen molecules. Glycogen, an energy-storage sugar made in our livers, can serve as a "sugar string" to trick cancer cells.
In a new approach, Cuellar and others in their Davidson biology lab are looking at ways to manufacture synthetic sugar strings that normally have to be produced within living cells. Such biology outside cells could end up being the most efficient and cost-effective way to produce ingredients for recipes against cancer.
"Today's technical advances mean that synthetic biology labs can look for ways to go ‘cell-free,'" said Malcolm Campbell, Herman Brown Professor of Biology and the director of the James G. Martin Genomics Program.
Campbell is Cuellar's adviser for the Davidson Research Initiative-funded biology portion of her research. Chemistry professor Nicole Snyder is providing additional funding and research mentorship to extend Cuellar's research through the summer. Cuellar will present her findings to top researchers at the American Society for Biochemistry and Molecular Biology and at the American Chemical Society national meetings in spring 2019.
Cuellar's love of science grew out of an early–and necessary–love of numbers. When she was in the third grade, her family moved from Mexico to the United States, and she spoke no English.
"But a number was always a number," she said.
In fourth grade, she ranked tops in her class in math. By fifth grade, her English had caught up, and she was on to science.
A Questbridge Scholar, Cuellar is majoring in chemistry and minoring in genomics. She easily crosses boundaries between the disciplines of biology, chemistry, and math.
"This summer, I've learned a lot about things I didn't necessarily think I would need to know a lot about, from antibodies to mass spectrometry," she said.
Outside the lab, she volunteers as a medical interpreter at the local clinic at Ada Jenkins Community Center in Davidson.
"Science is truly how I want to understand the world," said Cuellar. "And if we're talking about people not having access to medicine, I want to think about what we can do at the smallest level of detail to solve bigger problems."