Discovery of novel hybrids of diaryl-1,2,4-triazoles and caffeic acid as dual inhibitors of cyclooxygenase-2 and 5-lipoxygenase for cancer therapy

Inflammation plays a key role in cancer initiation and propagation. Cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX), two important enzymes in inflammatory responses are up-regulated in various tumor types. Dual inhibition of COX-2 and 5-LOX constitutes a rational concept for the design of more efficacious anti-tumor agents with an improved safety profile. We have previously reported a series of diaryl-1,2,4-triazole derivatives as selective COX-2 inhibitors. Herein, we hybridized the diaryl-1,2,4-triazoles with caffeic acid (CA) which was reported to display 5-LOX inhibitory and anti-tumor activities, affording a novel class of COX-2/5-LOX dual inhibitors as anti-tumor drug candidates. Most of these compounds exhibited potent COX-2/5-LOX inhibitory and antiproliferative activities in vitro. And the most potent compound 22b could significantly inhibit tumor growth in vivo. Furthermore, mechanistic investigation showed that the representative compound 15c blocked cell cycle in G2 phase and induced apoptosis in human non-small cell lung cancer A549 cells in a dose-dependent manner. Our preliminary investigation results would provide new clues for the cancer theatment with COX-2/5-LOX dual inhibitors.