A cell-permeable marine toxin. Disrupts microfilament-mediated processes. Actin polymerization inhibitor in vitro and in vivo by the formation of a 1:1 complex with monomeric G-actin. Depolymerizes actin filaments (F-actin) and acts as a phagocytosis inhibitor. Anticancer compound. Suppresses hypoxia-induced HIF-1 activation in tumor cells. Inhibits tumor cell invasion.