Use of nontoxic cyclic peptides to block transport via OATP1B1/ OATP1B3-related proteins, for the treatment of cancer cells expressing such transporters
The present invention relates in a first aspect to cyclic peptides being stable and non-toxic for specifically antagonising OATP1B1 and/or OATP1 B3. That is, the present inventors identified OATP1B1 and/or OATP1B3 specific antagonists being storable and non-toxic. In particular, the present invention relates to the use of stable, non-toxic cyclic peptides whereby said cyclic peptides have a long shelf life as well as being stable under acidic conditions. Furthermore, the present invention relates to cyclic peptides wherein cyclisation is realised by amino linkage. Said cyclic peptides are particularly useful for the treatment of cancer. In addition, the cyclic peptides allow to design OATP1B1 or OATP1 B3 specific antagonising compounds useful for the treatment of cancer or modulate the transport to these channels, in particular modulation of the transport in liver cells for preventing drug metabolism or having anti-toxic activity against hepatotoxic compounds.
