Abstract
Tumors are one of the most common fatal diseases worldwide and pose a severe threat to human health. Effective tumor prevention and treatment strategies are persistent challenges in the medical community. Angiogenesis plays a critical role in and is the basis for tumor development and metastasis. Circular RNAs (circRNAs) are novel single‑stranded covalently closed RNA molecules that are widely expressed in tumors due to their structural specificity and conservation. circRNAs affect angiogenesis by functioning as microRNA sponges to regulate vascular endothelial growth factor‑related pathways, thereby participating in various stages of tumor growth, invasion and proliferation. The present review summarizes the involvement of circRNAs in the regulation of tumor angiogenesis through competing endogenous RNA mechanisms, with a particular focus on the regulatory role of circRNAs in tumor angiogenesis in various systems. It is considered that circRNAs have great potential for use as tumor diagnostic markers and anti‑angiogenic therapies, and are thus worthy of further research and exploration.