Fralin Fellow investigates how environmental stress could promote tumor cell growth
July 29, 2015
In a well-lit laboratory on the southwest side of campus, Virginia Tech undergraduate Kimberly Soto-Alvarado focused a high-resolution microscope on a bright orange liquid in a small clear flask.
"Take a look," she said.
Through the microscope were tiny, worm-shaped cells squished together. "You can see that the cells have grown up to fill this small space, but there is no more room," she said, "so now we can look closer to see how the cells were affected by this environment."
Soto-Alvarado of Springfield, Virginia, a senior majoring in biological sciences in the College of Science, has spent her summer depleting human cells of nutrients, such as vitamins and proteins, to determine the point at which a cell’s environment changes enough to trigger mutations.
Ultimately, Soto-Alvarado’s work will help researchers determine how environmental conditions cause normal or pre-cancerous cells to form malignant tumors.
Low-nutrient environments are typical of developing cancers, she said, so her goal is to change the environment of healthy and typically pre-cancerous cells to coax them to mutate or show cellular defects, such as changes in chromosome number and errors during cell division.
"In a number of tumors, the pre-cancerous cells tend to display twice the normal number of chromosomes, which is a condition known as a tetraploidy," said Daniela Cimini, an associate professor of biological sciences in the College of Science and a Fralin Life Science Institute affiliate. "And there is evidence that tetraploidy may emerge in many cases during tumor progression."
Though cell mutations have been linked to altering amounts of chromosomes, it is not well understood how cells with twice the healthy amount of chromosomes, or tetraploidy, adapt and change to stressful environments, explained Soto-Alvarado, whose research has been supported by a Summer Undergraduate Research Fellowship from the Fralin Life Science Institute.
Under the mentorship of Cimini and Nicolaas Baudoin of Blacksburg, Virginia, a doctoral student in biological sciences, Soto-Alvarado alters the nutrient environment of two kinds of human cells: cells with the normal 46 chromosomes and cells with 92 chromosomes. When both normal and abnormal cells have access to few nutrients, the cells display greater variability in chromosome number, with the abnormal cells displaying greater variability than the normal cells.
"A greater variability in chromosomes makes cells more adaptable to certain environmental conditions. Therefore, we believe that by increasing chromosome number variability, tetraploidy makes cells more prone to tumor growth," Cimini said.
Much of Cimini’s work focuses on the role chromosomes play in making cells cancerous and treatment resistant, which is what attracted Soto-Alvarado to her research.
"Working on this project has provided me hands-on laboratory experience that has added a lot to my undergraduate coursework in biology and my interest in cancer research," Soto-Alvarado said. "I have also learned the process of performing science through the trials and errors of the scientific method."
Soto-Alvarado will present her research findings this week at the annual undergraduate research symposium on Thursday July 30, in Goodwin Hall.
Written by Cassandra Hockman, communications coordinator at the Fralin Life Science Institute.