Topology Control of Cancer Cell Monolayers Density by Liquid Crystal Networks

Cancer cells in tumors in vivo can form dynamic patterns, such as oncostreams and topological defects, which are able to regulate tumor growth, invasion, cell migration and apoptosis. In particular, it has been shown that topological defects can be centers for apoptosis, impact cell density, or even serve to stimulate growth and mound formation. Thus, it would be important to design means to regulate the organization of cells into topological defects with predictable function. For example, we could engineer topological defects that cause cells to enter apoptosis, a manner of designing a method to kill tumor cells using purely physical means. To do so we created liquid crystal network substrates printed onto glass slides patterned to display arrays or individual topological defects. We then plated mouse glioma cells or onto the glass slides, cultured cells for various days, and then analyzed the cells’ growth patterns.

Glioma cells grew on +1/2, -1/2, and +1 (circular and aster) defects. Interestingly, cells appeared unable to grow on -1 defects in isolation, though they did grow on arrays of +1/-1 defects. Further, cells accumulated at the center of circular +1 defects, and were reduced in the center and arms of +1 aster defects. This indicates that the network patterns are able to program the distribution of glioma cells and may determine cell density along defects. Our long-term aim is to deploy topological defects into tumors in vivo to control cell density and death in brain tumors.