Vimentin contributes to human mammary epithelial cell migration

Vimentin expression in human mammary epithelial MCF10A cells was examined a s a function of their migratory status using an in vitro wound-healing mode l. Analysis of the trajectories of the cells and their migratory speeds by time lapse-video microscopy revealed that vimentin mRNA and protein express ion were exclusively induced in cells at the wound's edge which were active ly migrating towards the center of the lesion. Actin labeling showed the re organization of actin filaments in cells at the wound's edge which confirme d the migratory phenotype of this cell subpopulation. Moreover, the vimenti n protein disappeared when the cells became stationary after wound closure. Using cells transfected with the vimentin promoter controlling the green f luorescent protein gene, we also demonstrated the specific activation of th e vimentin promoter in the migratory cells at the wound's edge. Transfectio n of the antisense vimentin cDNA into MCF10A cells clearly reduced both the ir ability to express vimentin and their migratory speed. Taken together, t hese observations demonstrate that vimentin is transiently associated with, and could be functionally involved in, the migratory status of human epith elial cells.