Fascin is a major actin-bundling protein that regulatescell motility and has recently received attention as a promising prognosticmarker of metastatic cancer.32,33 In contrast to Mg2+-mediated bundles, fascin-induced bundles presented monoexponentialdecays of actin rotor DiSC2(3) with characteristic lifetimesbetween 1.8 and 2.4 ns, implying a homogeneous environment for therotor in the bundle interfilamentous space (Figure 2e,g,h). This evidence concerns the gene FSCN1 and metastatic malignant neoplasm.