Because it is suggested that some CFTR is expressed at the apical membrane in epithelial cells from CF patients [47], despite a reduced level when compared to non-CF cells, and because we found a positive effect of AnxA5, our aim was to highlight a non toxic mean to increase AnxA5 expression in F508del-CFTR expressing cells. The gene discussed is ANXA5; the disease is cystic fibrosis.