We speculate that by poisoning microtubule +ends, eribulin binding to tubulin at substoichiometric concentrations [4, 24] disturbs the binding of the tubulin polymerase ch-TOG, thereby impacting tubulin polymerization which translates in a decrease of microtubule growth speed; this does not require the delocalization of EB1 which occurs at higher eribulin concentrations in our cancer cell model. The gene discussed is C4B; the disease is cancer.