Study: Cancer Cells Move Faster in Mucus

Key Points:

• Scientists have discovered that cancer cells and fibroblasts travel more quickly through viscous fluids than they do through less dense ones.

• The revelation may explain why cancer cells and fibroblasts have a greater impact on the diseases than healthy cells.

• Scientists hope to learn how to influence the behavior of the dangerous cells in an effort to slow them down.

A collaboration between researchers from the University of Toronto, Johns Hopkins University and Vanderbilt University may have groundbreaking implications in the treatment of diseases like cancer and cystic fibrosis.

Contrary to conventional wisdom, the research team discovered that certain cells move more quickly through thick fluids. The study, published in Nature Physics, focused on cancer and fibroblast cells—both of which have ruffled edges that help “propel” them in an environment that would otherwise slow them down.

“This link between cell viscosity and attachment has never been demonstrated before,” said Sergey Plotnikov, a cell researcher at the University of Toronto. “We found that the thicker the surrounding environment, the stronger the cells adhere to the substrate and the faster they move—much like walking on an icy surface with shoes that have spikes, versus shoes with no grip at all.”

Not only do cancer cells and fibroblasts feature ruffled edges, but they both also migrate through dense fluids enroute to their target destination. This may explain why cancerous cells outpace healthy ones as the disease propagates. Likewise, fibroblasts may use the same mechanism to reach wounds in the lung and cause further scarring.

The research was born from an experiment that aimed to observe the motility of cancer cells. Yun Chen, assistant professor of mechanical engineering at Johns Hopkins University, and student Matthew Pittman observed that cancer cells traveled quicker than non-cancerous cells when an artificial viscous fluid was poured over them.

They attributed the cancerous cells’ speed to actin, an intracellular protein responsible for muscle contraction and cell movement. Columns of the protein stabilized in the presence of the viscous fluid, which in turn expanded the cells’ ruffled edges.

Understanding how the cells utilize this mechanism is critical, as the research team’s next goal is to devise more effective treatments for cancer and cystic fibrosis.