FKA-A NPs enhances PTX-A NPs efficacy to suppress ovarian cancer via regulating Skp2/YAP pathway.

Recurrence and distant metastasis after paclitaxel (PTX)-based chemotherapy in ovarian cancer (OC) patients remains a clinical obstacle. Flavokawain A (FKA) is a novel chalcone from kava plant that can induce G2/M arrest and inhibit invasion and metastasis in different tumor cells. In this study, we examined the effects and the molecular mechanism of sodium aescinate (Aes)-stabilized nanoparticles FKA-A NPs in enhancing the efficacy of PTX-A NPs in vitro and in vivo. We showed that FKA-A NPs combined with PTX-A NPs notably inhibited the proliferation and migration and reduced the expression of EMT-related markers in OCs. YAP nuclear translocation and its downstream signaling pathway were remarkably activated after PTX-A NPs treatment in OCs. FKA-A NPs obviously inhibited YAP nuclear translocation and reduced the transcriptional activity of YAP target genes. Simultaneously, FKA-A NPs dose and time dependently inhibited Skp2 expression in A2780 and Skov3 cells. In contrast, overexpression of Skp2 significantly attenuated the inhibition of FKA-A NPs on YAP nuclear translocation. In OC homograft mice, treatment with FKA-A NPs and PTX-A NPs significantly suppressed the growth of homograft tumor compared with PTX-A NPs but did not decrease mice's body weight. In summary, we demonstrate that FKA-A NPs enhance the efficacy of PTX-A NPs against OCs in vitro and in vivo via reducing Skp2 expression, thus suppressing YAP nuclear translocation and activity of its target genes.