Cancer’s Front Lines: Watching the Invasives
A new microfluidic device could help scientists understand the conditions that favor cancer’s spread.
The study of cancer cells’ invasiveness has just gone from the equivalent of moving little soldiers around on a table to staging live-action re-enactments. Researchers at the University of Michigan have developed a 3-D fluidic device to observe cancer cells at the “front,” or leading edge of invasion. The Michigan team’s device is designed to study “tumoroids,” or globular masses of cells, instead of single cells. The device surrounds the cells with a matrix made of hydrogel and collagen—a protein that helps the hydrogel hold its shape. Nutrients and fluid flow through molded channels within the gel without disturbing the matrix. The pressure of fluid flow through the matrix, however, changes with the amount of fluid being channeled.
The scientists studied how such changes, as well as the concentration of collagen, affected how quickly the cells at the leading edge of the tumoroid multiplied and spread into the collagen-hydrogel matrix.
The team compared two prostate cancer cell lines. Increasing the collagen in the matrix cut the cells’ invasiveness by half in the first cell line and by 10 times in the second. Cutting fluid flow entirely in a high-collagen matrix eliminated invasiveness in both cell lines. By measuring the expression of a growth differentiation factor, they determined that the front-line tumor cells were growing and multiplying faster than interior cells. This suggests, the researchers wrote, that the growth factor could serve as “a marker of active invasion.”
Overall, the researchers noted, the experimental setup is “a suitable in vitro preclinical model for cancer development and progression.” Next they plan to fully map the molecular expression profiles of the invading cells. The device, they believe, can also be used to characterize primary tumors, biopsies, and cancer cell lines to assess risk and develop treatment strategies for individual patients. The study was published in Scientific Reports.