Annexina2 as a target protein for chlorogenic acid in human lung cancer A549 cells

Chlorogenic acid, an important active component of coffee with anti-tumor activities, has been found for many years. However, the lack of understanding about its target proteins greatly limits the exploration of its anti-tumor molecular mechanism and clinical application. Here, in vitro and animal experiments showed that chlorogenic acid had a significant inhibitory effect on the proliferation of A549 cells. Using the spontaneous fluorescence characteristic of chlorogenic acid to screen the target proteins cleverly to avoid the problem of chemical modification increasing false positive, we identify and verify annexin A2 (ANXA2) as a covalent binding target of chlorogenic acid in A549 cells. Then, we discover that chlorogenic acid as an inhibitor of the binding of ANXA2 to p50 subunit inhibited the expression of downstream anti-apoptotic genes cIAP1 and cIAP2 of NF-κB signaling pathway in A549 cells in vitro and vivo. Moreover, we find chlorogenic acid hindered the binding of ANXA2 and actin maybe involved in the impediment of tumor cell cycle and migration. Thus, this work demonstrates that chlorogenic acid, as a binding ligand of ANXA2, decrease the expression of NF-κB downstream anti-apoptotic genes, inhibiting the proliferation of A549 cells in vivo and vitro.View Full Text