Pull the plug: Anti-angiogenesis potential of natural products in gastrointestinal cancer therapy

Gastrointestinal cancer (GIC), including gastric cancer and colorectal cancer, is a common malignant tumor originating from the gastrointestinal epithelium. Although the pathogenesis of GIC has not been fully elucidated, angiogenesis is recognized as the key pathological basis for the growth, invasion and metastasis of cancer cells, and GIC angiogenesis is closely related to vascular endothelial growth factor family, hypoxia-inducible factor family, fibroblast growth factor family and matrix metalloproteinase family. Recently, many natural products have shown a wide range of pharmacological biological activities against GIC. In this review, the effects and mechanisms of natural compounds on the angiogenesis of gastric and colorectal cancer were summarized. The results show that some natural compounds, especially gallic catechin gallate, astragaloside and curcumin, can effectively inhibit angiogenesis; the HIF-1α/VEGF, COX-2/PGE2, HGF/c-Met and PI3K/Akt/mTOR are involved in these inhibition effects. This review examines the anti-angiogenesis potential of natural products in the GIC treatment and provides clues to the development of vascular targeted agents.