Angiotensin peptides and lung cancer

Abstract

Lung cancer is a leading cause of death in both men and women, with over 1,000,000 new cases diagnosed worldwide annually and a 5-year survival rate of only 14%, a figure that has improved little in the past thirty years. This poor prognosis suggests a need for novel approaches for the treatment and prevention of lung cancer. The renin-angiotensin system is an established, primary regulator of blood pressure, homeostasis, and natriuresis; however, compelling evidence indicates that the angiotensin peptides also play a role in cell proliferation and inflammation. Angiotensin II is a vasoconstrictor, a mitogen, and an angiogenic factor, while angiotensin-(1-7) has vasodilator, anti-proliferative, and anti-angiogenic properties. This review focuses on studies examining the renin-angiotensin system in pulmonary cancers and whether clinical intervention of this pathway may serve as an effective chemotherapeutic and/or chemopreventive modality for lung cancer.

Fig. (1)

The renin-angiotensin system.

Fig. (2)

Effect of ACE inhibition on angiotensin peptides.

Fig. (3)

Reduction of VEGF-A in human A549 lung tumor xenografts infused with saline or Ang-(1-7). n = 3 for each group.

Fig. (4)

Ang-(1-7) inhibition of endothelial cell tubule formation. Panel A – A representative photograph of endothelial cells incubated with or without Ang-(1-7) on Matrigel. Panel B – Quantification of tubule number following 16 h treatment with various doses of Ang-(1-7). *p<0.05; n = 3-5.