You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Chemical"].

Please return the output as a JSON object of the format: {"Chemical": ["Arsenic", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Antiangiogenic effects of p-coumaric acid in human endothelial cells. p-Coumaric acid, a hydroxy derivative of cinnamic acid, has been known to possess antioxidant and anticancer activities. Despite its potential contribution to chemopreventive effects, the mechanism by which p-coumaric acid exerts its antiangiogenic actions remains elusive. In this study, we revealed that p-coumaric acid inhibited the sprouting of endothelial cells in rat aortic rings and inhibited the tube formation and migration of endothelial cells. We observed that p-coumaric acid could downregulate mRNA expression levels of the key angiogenic factors vascular endothelial growth factor and basic fibroblast growth factor. Also, we demonstrated that p-coumaric acid inhibited both the AKT and ERK signaling pathways, which are known to be crucial for angiogenesis. Using a mouse model, we also showed that p-coumaric acid effectively suppressed tumor growth in vivo by lowering hemoglobin contents. Collectively, these findings indicate that p-coumaric acid possesses potent anticancer properties due to the inhibition of angiogenesis in vivo. Copyright © 2012 John Wiley & Sons, Ltd.
{"Chemical": ["p-coumaric acid", "p-Coumaric acid", "hydroxy", "cinnamic acid"]}