Overexpression of ACE2 produces antitumor effects via inhibition of angiogenesis and tumor cell invasion in vivo and in vitro.

Angiotensin II (AngII) is a multifunctional bioactive peptide in the renin-angiotensin system (RAS). Angiotensin-converting enzyme 2 (ACE2) is a newly identified component of RAS. The role of AngII and ACE2 in the metastasis of non-small cell lung cancer (NSCLC) and the effects on matrix metalloproteinases (MMPs) are still unknown. In the present study, the anti-invasive effect and mechanism of ACE2 were investigated in vitro and in vivo. Results of a transwell assay showed that the overexpression of ACE2 reduces the invasive ability of A549 cells in vitro. According to the results of qRT-PCR and western blot analysis, the inhibitory role of ACE2 was mediated through the down-regulation of MMP-2 and MMP-9. Additionally, we confirmed that the overexpression of ACE2 inhibited cell growth and VEGFa production while simultaneously suppressing ACE and angiotensin II type 1 receptor (AT1R) expression in human lung cancer xenografts. These results suggest that the overexpression of ACE2 may potentially suppress the invasion and angiogenesis of NSCLC.