From carbohydrate to peptidomimetic inhibitors of galectins

Although the roles that galectins play in controlling and mediating various biological processes is ever growing, only recently have galectins been accepted as valid therapeutic targets for clinical intervention. Because galectin inhibitors have therapeutic potential in many areas, e.g. as anti-inflammatory, anti-cancer, and even anti-HIV-1 agents, considerable efforts are being made by many laboratories to discover or design galectin antagonists. However, none are presently available for standard-of-care use in the clinic. To date, most galectin antagonists target the carbohydrate binding site, and as such are generally ß-galactoside-analogs and glycomimetics. Several peptide-based galectin inhibitors have also been reported, and one of these, calixarene-based peptidomimetic PTX008 that targets galectin-1, is presently in a phase I clinical trial. This review provides an overview of various galectin inhibitors reported to date.