Adjuvant Properties of Caffeic Acid in Cancer Treatment

Caffeic acid (CA) is a polyphenol belonging to the phenylpropanoid family, commonly found in plants and vegetables. It was first identified by Hlasiwetz in 1867 as a breakdown product of caffetannic acid. CA is biosynthesized from the amino acids tyrosine or phenylalanine through specific enzyme-catalyzed reactions. Extensive research since its discovery has revealed various health benefits associated with CA, including its antioxidant, anti-inflammatory, and anticancer properties. These effects are attributed to its ability to modulate several pathways, such as inhibiting NFkB, STAT3, and ERK1/2, thereby reducing inflammatory responses, and activating the Nrf2/ARE pathway to enhance antioxidant cell defenses. The consumption of CA has been linked to a reduced risk of certain cancers, mitigation of chemotherapy and radiotherapy-induced toxicity, and reversal of resistance to first-line chemotherapeutic agents. This suggests that CA could serve as a useful adjunct in cancer treatment. Studies have shown CA to be generally safe, with few adverse effects (such as back pain and headaches) reported. This review collates the latest information from Google Scholar, PubMed, the Phenol-Explorer database, and ClinicalTrials.gov, incorporating a total of 154 articles, to underscore the potential of CA in cancer prevention and overcoming chemoresistance.