Metastatic Cancer Cells and Shear Stress
How do metastatic cancer cells survive the remarkable stresses of the human bloodstream?
In 2011, more than half a million Americans died from metastatic cancer — cancer that spreads from its original site to another location in the body.
IIHR Assistant Research Engineer Sarah Vigmostad is part of research team working to learn more about these metastatic cancer cells and how they survive the remarkable stresses of the human bloodstream.
Vigmostad, who is also an assistant professor of biomedical engineering, says the metastatic cancer cells have an almost uncanny ability to undergo shear stresses in the bloodstream and emerge stronger than before. “As they navigate through the bloodstream, they’re potentially exposed to very high stresses,” she explains. “It appears that the metastatic cells are somehow adapting, so that over time, their survival rate improves. If they continue to be exposed to shear stress, they seem to somehow improve their survival.”
It’s easy to start thinking about these metastatic cancer cells as almost supernaturally resilient, Vigmostad admits. “Cells are crazy!” she says. “Cells are living things, and so you observe this in a lot of different instances — this quick response of cells to mechanical stimuli.”
Vigmostad and her team are hoping to better understand what’s at play with the metastatic cells, and what this might mean for scientists trying to better understand the disease and identify metastatic cancer cells within the circulatory system. She says the team is using fluid mechanics knowledge and the ability to model cell dynamics to understand some of the processes that take place during cancer metastasis.
This area offers a number of challenging puzzles, Vigmostad says. Circulating cancer cells are often found in a cancer patient’s bloodstream, but that’s not necessarily an indicator that the cancer is going to metastasize. Researchers want to learn why some cells are successfully metastasizing after they enter the bloodstream, and how they differ from other cells.
She is collaborating with Michael Henry from the Department of Molecular Physiology and Biophysics. His group observed differences in the behavior of metastatic cancer cells and non-metastatic cancer cells. They have been struggling to understand and explain these disparities, Vigmostad says. She hopes the computational tools and experimental mechanics can help shed some light on the question.
Vigmostad’s research team is using micro-pipette aspiration to quantify the cells’ material properties, which may help the cells survive in the bloodstream. Researchers apply suction to the metastatic cancer cell through a micro-pipette smaller than the individual cell diameter, and very slowly aspirate part of the cell into the micro-pipette. “The material properties of the cell are going to dictate how quickly the cells come into the pipette and what kinds of pressures are needed,” Vigmostad says. “That can help us quantify the material properties of those cancer cells.”
Using micro-PIV (micro resolution particle image velocimetry), Vigmostad also hopes to be able to visualize the interactions between cells as they flow through the body. “We’re interested to see what the dynamic is between cancer cells and blood cells, and whether there’s a different dynamic when have metastatic cells vs. healthy or non-metastatic cells.”
It’s a promising area of research where much still remains unknown. “I think we have a lot of potential to explore important questions related to metastasis,” Vigmostad says. “It’s very exciting. But it’s never as straightforward as you think it’s going to be.”