Chlorogenic acid for cancer prevention and therapy: Current status on efficacy and mechanisms of action

Chlorogenic acid (CA), also known as 5-O-caffeoylquinic acid, is a dietary phenolic acid produced by various plant species. CA, is the most ubiquitous compound among the phenolic acid group, is also present in tea and green coffee extracts. Its consumption reduces the risk of numerous diseases as validated by preclinical and clinical studies. CA possesses a wide range of pharmacological properties, such as hepatoprotective, antimicrobial, immunomodulatory, antioxidant, antidiabetic, and anticancer activities. It has been extensively used in the food, chemical, medicine, and health care industries. Available reports revealed that CA can exert anticancer activity by inhibiting the cell cycle, triggering apoptosis, and suppressing the proliferation of cancer cells. It upregulates the expression of nuclear factor of activated T cells 2 (NFATC2) and NFATC3 genes involved in immune pathway and downregulates B cell-specific moloney murine leukemia virus integration site 1 protein and SRY-box transcription factor 2 gene expression to facilitate tumor cell destruction. It promotes intracellular DNA impairment and topoisomerase I- and topoisomerase-II-DNA complex formation that perform a key function in apoptosis. In addition, CA has been documented to be an effective natural anticancer drug and was approved by the China Food and Drug Administration. Several previously published reports have provided fragmented summary of various anticancer activities of CA. Therefore, this review aims to deliver up-to-date and comprehensive assessment about the natural sources of CA, its bioavailability, metabolism, and anticancer property with an emphasis on the molecular mechanisms associated with several signaling pathways in tumor cells.