NOS2 and Cowden syndrome 1: Furthermore, down-regulation of iNOS expression suppresses the production of inflammatory cytokines as well as matrix metalloproteinases, which are essential molecules for the development of CS [3], suggesting that CAM administered orally and M-4 synthetized from CAM cause a decrease in iNOS expression in cytosol after inflammatory stimulation, inhibiting superoxide generation and resulting in prevention of tissue injury in patients with chronic airway diseases, including CS.