What do cells talk about? Years of research have shown us that cells secrete and receive chemical substances to interact with each other. Clearly chemicals play a major role in cell communication, but is there more to the language of cells?
Prof. Mingming Wu, biological and environmental engineering, and her colleagues research ways in which cells use their physical environment to communicate with each other. Specifically, cells placed in a matrix of microscopic fibers interact with these fibers to send out signals. As opposed to the chemical signals that have been thoroughly researched, these cells use the physical fibrous network around them to relay messages.
Studying such microscopic phenomena is challenging. To run experiments, Wu and Matthew Hall ’16 used a cell tank, an aquarium of sorts. A synthetic gel containing cells was then placed into the tank. However, creating a gel that mimics the natural matrix found in animal tissues is difficult. Biological tissues do not resemble simple, crisscross, linear patterns as much as they resemble tangled spaghetti.
After creating the gel, the team then placed tumour cells in it to study their interactions with the matrix. To do so, fluorescent beads were added to the matrix fibers so as to make any physical changes apparent as well as aid calculations of the forces these cells exert. Their observations revealed that the tumour cells pulled on the fibres and used them to propel themselves forward. Such findings are important because they could help explain how malignant cancer cells move rapidly in the body.
“It was harder than I thought, but I didn’t think it was impossible. Sometimes the community tells you that this is way too hard but I was trained as a physicist so I thought if something exists you got to be able to measure it,” Wu said.
Furthermore, the tumour cells seemed to use this pulling action to communicate with other cells in the vicinity. This communication seemed to increase significantly when there was more sugar in the matrix. Thus, patients with higher levels of sugar such as those with diabetes would have greater communication between cancer cells and possibly experience a faster progression of the disease.
Wu plans to study these mechanisms in more realistic conditions, especially in the presence of fluids as is the case in actual animal tissue. She hopes that their research will eventually help them predict the direction of movement of cancer cells. Such prediction methods would support research that aims to control their movement and restrict them to certain regions.
Wu also credits the interdisciplinary approach behind the study. Prof. Chung-Yuen Hui, mechanical and aerospace engineering, played a pivotal role in the theory behind the experiments.
“I think that collaboration shows us that biological engineering is quite interdisciplinary, it is tough for one person to just sit there and do something. One really needs everyone to work together,” Wu said.
Wu’s research brings together the fields of cellular biology, physics and bio engineering to provide insights into the different ways cells communicate with each other. In time, propelled by a deeper understanding of how cells, especially cancer cells, move around in the body, such research may lead to new tools in the ongoing fight against the disease.