  The precise role of the microenvironment on tumor growth is poorly
understood. Whereas the tumor is in constant competition with the surrounding
tissue, little is known about the mechanics of this interaction. Using a novel
experimental procedure, we study quantitatively the effect of an applied
mechanical stress on the long-term growth of a spheroid cell aggregate. We
observe that a stress of 10 kPa is sufficient to drastically reduce growth by
inhibition of cell proliferation mainly in the core of the spheroid. We compare
the results to a simple numerical model developed to describe the role of
mechanics in cancer progression.
