hMENA is a key regulator in endothelin-1/beta-arrestin1-induced invadopodial function and metastatic process

Aberrant activation of endothelin-1 receptors (ET-1R) elicits pleiotropic effects relevant for tumor progression. The network activated by this receptor might be finely, spatially, and temporarily orchestrated by beta-arrestin1 (beta-arr1)-driven interactome. Here, we identify hMENA, a member of the actin-regulatory protein ENA/VASP family, as an interacting partner of beta-arr1, necessary for invadopodial function downstream of ET-1R in serous ovarian cancer (SOC) progression. ET-1R activation by ET-1 up-regulates expression of hMENA/hMENA Delta v6 iso-forms through beta-arr1, restricted to mesenchymal-like invasive SOC cells. The interaction of beta-arr1 with hMENA/hMENA Delta v6 triggered by ET-1 leads to activation of RhoC and cortactin, recruitment of membrane type 1-matrix metalloprotease, and invadopodia maturation, thereby enhancing cell plasticity, transendothelial migration, and the resulting spread of invasive cells. The treatment with the ET-1R antagonist macitentan impairs the interaction of beta-arr1 with hMENA and inhibits invadopodial maturation and tumor dissemination in SOC orthotopic xenografts. Finally, high ETAR/hMENA/beta-arr1 gene expression signature is associated with a poor prognosis in SOC patients. These data define a pivotal function of hMENA/hMENA Delta v6 for ET-1/beta-arr1-induced invadopodial activity and ovarian cancer progression.