Exosomal EGFR and miR-381-3P mediate HPV-16 E7-induced angiogenesis of non-small cell lung cancer

Background Our previous studies have demonstrated that exosomal epidermal growth factor receptor (EGFR) and exosomal miR-381-3P expression were significantly increased in HPV-16 E7-overexpressing non-small cell lung cancer (NSCLC) cells. Moreover, exosomal EGFR was involved in HPV-16 E7-induced EMT in NSCLC cells. In this study, we further investigated the effect of exosomes derived from HPV-16 E7-overexpressing NSCLC cells on angiogenesis and the roles of exosomal EGFR and exosomal miR-381-3P in it. Methods The exosomes derived from the stable HPV-16 E7-overexpressing A549 and H460 NSCLC cells (E7 Exo) and empty vector-infected cells (ev Exo) were isolated by ultracentrifugation. Colony formation assay and Transwell assay were performed to observe the effect of E7 Exo on the abilities of colony formation and migration of human umbilical vein endothelial cells (HUVECs). Additionally, cell and animal experiments were used to analyze the effect of E7 Exo on angiogenesis. Furthermore, the roles of exosomal EGFR and miR-381-3p in angiogenesis were explored through the inhibition EGFR activation and exosome secretion or overexpression of miR-381-3p, respectively. Results Compared with ev Exo, both A549 E7 Exo and H460 E7 Exo significantly enhanced colony formation and migration abilities of HUVECs. Moreover, E7 Exo dramatically promoted tube-forming abilities cells in vitro ( P < 0.01) and angiogenesis in vivo ( P < 0.01). The inhibition EGFR activation and exosome secretion of NSCLC cells suppressed HPV-16 E7-induced migration and tube formation of HUVEC cells in vitro ( P < 0.01), and significantly deceased the levels the Ang-1 and VEGFA proteins, angiogenesis-related markers ( P < 0.01). The tube-forming abilities of HUVECs transfected with miR-381-3p mimics and then treated with E7 Exo were significantly enhanced as compared with cells treated with E7 Exo only ( P < 0.01), while transfection of miR-381-3p inhibitor reversed this effect ( P < 0.05). Conclusion Exosomal EGFR and exosomal miR-381-3p may be involved in HPV-16 E7-induced angiogenesis of NSCLC.