Galectin-3 inhibitors: a patent review (2008-present)

Galectin-3 (Gal-3), a lectin with preference for β-galactoside-containing carbohydrates, is a structurally unique member of the galectin family. It is ubiquitously expressed in various mammalian tissues with a wide distribution from the intracellular environment to the extracellular space. Gal-3 is a well-established player in numerous diseases, from infections to heart failure. Notably, as Gal-3 overexpression is associated with cancer drug resistance, it has been identified as a valuable therapeutic target in the fight against cancers.

This review discusses the recent progress of patent applications (2008-present) and the current knowledge of pertinent Gal-3-inhibitor interactions in an effort to progress the development of selective and high affinity carbohydrate-based inhibitors targeting Gal-3, with an emphasis on engaging a structure-based drug design rationale.

The lack of commercially available anti-Gal-3 therapeutic reagents and its clear involvement in serious disease, notably cancer, leads to an urgent need for development of inhibitors that specifically target Gal-3. Design of potent and selective carbohydrate inhibitors targeting Gal-3 is challenging due to relative weak protein-carbohydrate interactions along with the high sequence homology in the carbohydrate binding site region among galectins. To date, some chemical scaffolds have been exploited for design of promising effective Gal-3 inhibitors for cancer therapy.