 In general the dynamics are normally suppressed by low, subtoxic concentrations of microtubule drugs that also inhibit cell migration.However, incorporating β3-tubulin into microtubules increases the concentration of drug that is needed to suppress dynamics and inhibit cell migration.Thus, tumors that express β3-tubulin are not only resistant to the cytotoxic effects of microtubule targeted drugs, but also to their ability to suppress tumor metastasis.