14 DAY TRIAL // A group of researchers from the Johns Hopkins University (JHU) announce a significant discovery related to the way cancer cells move through the human body. The team says that the model currently used to explain these motions, called random walk, does not hold true when assessing cellular motions in 3D. The model was developed based on observations conducted on 2D lab cultures.
Random walk is a term researchers use to denote cancer cells that move through the human body in a very slow and apparently-aimless pattern. However, the JHU team determined that this range of motions does not hold true when investigating cells inside the body, in three dimensions. In other words, the pattern is only true for tumor cells moving across the confines of Petri dishes.
The new investigation could have significant implications for researchers studying cancer spread patterns. These studies are very important because they can help oncologists design timely interventions for patients at risk of developing metastasis, which is the generalized spread of cancer to all organs in the body. This is usually the step where the disease becomes incurable and lethal.
Details of the new study, led by the JHU Theophilus H. Smoot professor, Denis Wirtze, are published in the March 4 early online issue of the esteemed journal Proceedings of the National Academy of Sciences (PNAS). Wirtze's team has been conducting research on the differences between cancer cells in 2D and 3D settings for several years.
“Cancer cells that break away from a primary tumor will seek out blood vessels and lymph nodes to escape and metastasize to distant organs. For a long time, researchers have believed that these cells make their way to these blood vessels through random walks,” Wirtz explains.
“In this study, we found out that they do not. Instead, we saw that these cells will follow more direct, almost straight-line trajectories. This gives them a more efficient way to reach blood vessels – and a more effective way to spread cancer,” the team leader goes on to say.
The main implication here is that cancer cells can make their way to their targets a lot faster than previously estimated, meaning that doctors have far less time available to come up with an effective course of treatment. The new investigation was supported by the National Institutes of Health.
“Cells that are moving through a 3D environment seem to be more directional than those moving across a flat 2D surface. The unpredictable ‘random walk’ is not prevalent in a 3D environment,” says co-lead study author Anjil Giri, a PhD student with the Department of Chemical and Biomolecular Engineering at JHU.