Dual regulation of autophagy: paradoxical effects on tumor angiogenesis

Autophagy plays a critical role in dynamic cell growth under different environmental conditions and maintains cellular homeostasis and cell viability in response to different cellular injuries, especially in tumor angiogenesis, where there is a controversial dual role. Angiogenesis plays a key role in facilitating tumor development. Therefore, investigating the mechanism of action of autophagy in the flexible shift of tumor angiogenesis is essential for antiangiogenic clinical therapy, and modulating the autophagy process is expected to constitute a new strategy to inhibit tumor angiogenesis and stop tumor growth and spread. This review highlights the close connection between autophagy and tumor angiogenesis. We also attempt to explain the seemingly contradictory promotion or inhibition of angiogenesis in tumor development reported in past studies. We focus on the potential clinical value of autophagy agonists and inhibitors in antiangiogenic therapy, which will provide new theoretical bases for antitumor therapy and may lead to innovative therapeutics.