PTGS2 and malignant colon neoplasm: In addition, eugenol modulated growth and cyclooxygenase-2 expression in human colon cancer HT-29 cells25, exerted an antiproliferative effect on colon cancer cells (HCT-15 and HT-29)26 and inhibited growth of human breast cancer MCF-7 cells in a dose-dependent manner, accompanied by a depletion in GSH and an increase in peroxidation activity27.