An update on small molecules targeting CXCR4 as starting points for the development of anti-cancer therapeutics.

CXCR4 (C-X-C Chemokine Receptor type 4) and its natural ligand SDF-1α (Stromal-Derived-Factor-1α) are involved in a number of physiological and pathological processes including cancer spread and progression. Over the past few years, numerous CXCR4 antagonists have been identified and currently are in different development stages as potential agents for the treatment of several diseases involving the CXCR4/SDF-1α axis. Herein, we focus on small molecules reported in literature between 2013 and 2017, claimed as CXCR4 antagonists and potentially useful in the treatment of cancer and other diseases where this receptor is involved. Most of the compounds resulted from a chemical optimization of previously identified molecules and some of them could represent suitable candidates for the development of advanced anticancer agents.