MMP9 and cancer: Liu et al. (2017) found that ellagic acid gradually reduced MMP-2 and MMP-9 levels in cancer studies. Carnosic acid, a catechol-type electrophilic molecule, activates the Keap1/Nrf2 transcriptional pathway by binding specific cysteine residues on Keap1, protecting against oxidative stress (Satoh et al., 2008). Yu et al. (2008) demonstrated that these inhibitory mechanisms of carnosic acid may interrupt a signaling event involving MMP-9 transcription-mediated activation of NF-kB and, based on this conclusion, CA reduced MMP-9 expression.