title: Caffeine induces matrix metalloproteinase-2 (MMP-2) and MMP-9 down-regulation in human leukemia U937 cells via Ca2+/ROS-mediated suppression of ERK/c-fos pathway and activation of p38 MAPK/c-jun pathway.
abstract: Caffeine attenuated invasion of human leukemia U937 cells with characteristic of decreased protein expression and mRNA levels of matrix metalloproteinase-2 (MMP-2) and MMP-9. Down-regulation of MMP-2 and MMP-9 in U937 cells was abrogated by abolishment of caffeine-elicited increase in intracellular Ca(2+) concentration and ROS generation. Pretreatment with BAPTA-AM (Ca(2+) chelator) and N-acetylcysteine (ROS scavenger) abolished caffeine-induced ERK inactivation and p38 MPAK activation. Moreover, caffeine treatment led to MAPK phosphatase-1 (MKP-1) down-regulation and protein phosphatase 2A catalytic subunit (PP2Ac) up-regulation, which were involved in cross-talk between p38 MAPK and ERK. Transfection of constitutively active MEK1 or pretreatment with SB202190 (p38 MAPK inhibitor) restored MMP-2 and MMP-9 protein expression in caffeine-treated cells. Caffeine treatment repressed ERK-mediated c-Fos phosphorylation but evoked p38 MAPK-mediated c-Jun phosphorylation. Knock-down of c-Fos and c-Jun by siRNA reflected that c-Fos counteracted the effect of c-Jun on MMP-2/MMP-9 down-regulation. Taken together, our data indicate that MMP-2/MMP-9 down-regulation in caffeine-treated U937 cells is elicited by Ca(2+)/ROS-mediated suppression of ERK/c-Fos pathway and activation of p38 MAPK/c-Jun pathway.
authors.affiliation: Institute of Biomedical Sciences, National Sun Yat-Sen University-Kaohsiung Medical University Joint Research Center, National Sun Yat-Sen University, Kaohsiung, Taiwan.
authors.forename: Wen-Hsin
authors.initials: WH
authors.lastname: Liu
authors.forename: Long-Sen
authors.initials: LS
authors.lastname: Chang
mesh_terms: D000818:Animals; D002110:Caffeine / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D015536:Down-Regulation; D004789:Enzyme Activation; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism*; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D020298:U937 Cells / Q000187:drug effects* / Q000502:physiology
chemical_list: D010726:Phosphodiesterase Inhibitors; D016760:Proto-Oncogene Proteins c-fos; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; D002110:Caffeine; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D002118:Calcium