In a recent Scientific American article called “Viewing Cancer as a Physics Problem Suggests New Treatments,” Rakesh K. Jain, of Massachusetts General Hospital and Harvard Medical School, notes that cells and a stiff fibrous material known as the matrix can squash blood vessels inside tumors. As a consequence, oxygen and anticancer drugs flowing in the blood get stopped in their tracks, unable to penetrate beyond the pinched areas. Starved of oxygen and spared from attacks by anticancer agents, malignant cells in many parts of the tumor proliferate and may even become more aggressive. The article goes on to describe methods under study to deplete the matrix, thereby easing compressive forces and allowing blood vessels to open and distribute blood—and thus oxygen and drugs—throughout a mass.
To assess the compressive stresses in the tumors of lab animals, Jain and his colleagues slice the masses, measure how much they swell in response to the cut and feed the information into mathematical formulas the group has developed.
Watch the swelling in one such tumor, a mammary cancer from a mouse, below. The ruler visible in the movie is included for scale.
Video reproduced from (pdf).
Right now, the group applies the technique only in the lab, evaluating how well various substances ease compressive forces in tumors. If reducing compression turns out to enhance the effectiveness of anticancer drugs in matrix-rich tumors in humans, the technique could, in principle, also help doctors to determine which patients might be good candidates for receiving matrix-depleting agents, along with more standard treatments.