COX2-Inhibitory and Cytotoxic Activities of Phytoconstituents of Matricaria chamomilla L.

Abstract

Chamomile tea is a popular beverage and herbal remedy with various health benefits, including antioxidant and antimicrobial activities and beneficial effects on metabolism. In this study, we investigated the inhibitory activities of secondary metabolites from Matricaria chamomile L. against COX2, an enzyme involved in inflammation and linked to cancer development. The cytotoxicity of the compounds was also evaluated on a panel of 60 cancer cell lines. Myricetin, one of the COX2-inhibiting and cytotoxic compounds in chamomile tea, was further studied to determine a proteomic expression profile that predicts the sensitivity or resistance of tumor cell lines to this compound. The expression of classical mechanisms of anticancer drug resistance did not affect the responsiveness of cancer cells to myricetin, e.g., ATP-binding cassette (ABC) transporters (ABCB, ABCB5, ABCC1, ABCG2), tumor suppressors (p53, WT1), and oncogenes (EGFR, RAS), whereas significant correlations between myricetin responsiveness and GSTP expression and cellular proliferation rates were observed. Additionally, Kaplan–Meier survival time analyses revealed that high COX2 expression is associated with a worse survival prognosis in renal clear cell carcinoma patients, suggesting a potential utility for COX2 inhibition by myricetin in this tumor type. Overall, this study provides insight into the molecular modes of action of chamomile secondary metabolites and their potential as cancer-preventive or therapeutic agents.