The present invention relates to methods and pharmaceutical compositions for the treatment of cystic fibrosis (CF). In particular, the present invention relates to a method of treating cystic fibrosis in a subject in need thereof comprising administering to the subject a therapeutically effective amount of an antisense Oligonucleotide Target Site Blocker (TSB) that binds to a specific microRNA recognition site of ANO1 mRNA.
Autors show that ANO1 chloride channel activity is decreased in CF bronchial epithelial cells due to a decrease in ANO1 protein expression. Use of specific TSB oligonucleotides allows to increase ANO1 expression, chloride activity and mucus dynamics in primary CF cells isolated from bronchial biopsies from CF patients. An additive effect of the TBS is observed on the mucus dynamics in Orkambi treated primary human bronchial epithelial and fully differentiated cells isolated from bronchial biopsies from CF patients. Specific TSB increases ANO1 chloride activity and mucus dynamics in trachea of CF mice.