Tubulin polymerization-IN-61 (Compound 9a) is a tubulin polymerization inhibitor. Tubulin polymerization-IN-61 destroys the microtubule skeleton, blocks the cell cycle in G2/M phase, induces Apoptosis , and inhibits cancer cell migration and colony formation. Tubulin polymerization-IN-61 shows antitumor activity in vivo against 4T1 xenograft model.