Annexin A2,a multifunctional tumor associated protein,promotes nuclear factor-kappa B (NF-κB) activation by interacting with NF-κB p50 subunit and facilitating its nuclear translocation.Here we demonstrated that two ginsenosides Rg5 (G-Rg5) and Rk1 (G-Rk1),with similar structure,directly bound to Annexin A2 by molecular docking and cellular thermal shift assay.Both Rg5 and Rk1 inhibited the interaction between Annexin A2 and NF-κB p50 subunit,their translocation to nuclear and NF-κB activation.Inhibition of NF-κB by these two ginsenosides decreased the expression of inhibitor of apoptosis proteins (lAPs),leading to caspase activation and apoptosis.Over expression of K302A Annexin A2,a mutant version of Annexin A2,which fails to interact with G-Rg5 and G-Rk1,effectively reduced the NF-κB inhibitory effect and apoptosis induced by G-Rg5 and G-Rk1.In addition,the knockdown of Annexin A2 largely enhanced NF-κB activation and apoptosis induced by the two molecules,indicating that the effects of G-Rg5 and G-Rk1 on NF-κB were mainly mediated by AnnexinA2.Taken together,this study for the first time demonstrated that G-Rg5 and G-Rk1 inhibit tumor cell growth by targeting Annexin A2 and NF-κB pathway,and G-Rg5 and G-Rk1 might be promising natural compounds fortargeted cancer therapy.