MMP14 and cancer: Figure 8b and c confirms that both proteolysis and cancer cell–cancer cell adhesion are required for effective cell growth in 3D collagen matrices. Moreover, the positive effect of boosting proteolysis required cell-cell adhesions (Figure 8b and c compares MMP14 OE with αCATKO MMP14 OE). Ectopic activation of ROCK2, which disrupts cytoskeletal cohesion in cell clusters, also reduced growth in 3D collagen (Figure 8—figure supplement 1d and e).