Association of suppression of extracellular signal-regulated kinase phosphorylation by epigallocatechin gallate with the reduction of matrix metalloproteinase activities in human fibrosarcoma HT1080 cells.
Matrix metalloproteinases (MMPs) play a crucial role in the process of cancer invasion and metastasis. Previous findings suggested that epigallocatechin gallate (EGCG), a main flavanol of green tea, caused decreased levels of MMP-2 and MMP-9 activities to be secreted into culture medium. To obtain further information on EGCG-mediated regulation of these MMPs, the effects of EGCG on enzyme activity, mRNA expression, and mitogen-activated protein kinase (MAPK) activities in human fibrosarcoma HT1080 cells were examined. EGCG was confirmed to suppress the gelatin-degrading activities due to MMP-2 and MMP-9 in the culture medium. This suppression of enzyme activities by EGCG was consistent with the decreased levels of MMP-2 and MMP-9 mRNAs. EGCG-mediated suppression was also observed for MT1-MMP mRNA. EGCG-mediated suppression of the level of MMP-9 transcript was correlated with its suppression of MMP-9 promoter activity. EGCG inhibited the phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2), which are the members of an MAPK family necessary for MMP-9 up-regulation. EGCG also suppressed p38 MAPK activity but gave no effects on stress-activated protein kinase/c-Jun N-terminal kinase activity. These findings suggest that suppression of ERK phosphorylation by EGCG is involved in the inhibition of expression for MMP-2 and MMP-9 mRNAs, leading to the reduction of their enzyme activities of the cancer cells. Methyl derivatives, epigallocatechin-3-O-(3-O-methyl) gallate and epigallocatechin-3-O-(4-O-methyl) gallate, exhibited effects similar to, but weaker than, those of EGCG, suggesting the important role of an unsubstituted triphenolic ester structure in these activities.
Maeda-Yamamoto
Mari
M
National Institute of Vegetable and Tea Science, NARO, 2769 Kanaya, Shizuoka 428-8501, Japan. marimy@affrc.go.jp
Suzuki
Naoko
N
Sawai
Yoshinori
Y
Miyase
Toshio
T
Sano
Mitsuaki
M
Hashimoto-Ohta
Akiko
A
Isemura
Mamoru
M
D028241:Camellia sinensis / Q000737:chemistry; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000493:pharmacokinetics*; D005354:Fibrosarcoma / Q000201:enzymology*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000235:genetics; D020780:Matrix Metalloproteinase 9 / Q000235:genetics; D061965:Matrix Metalloproteinase Inhibitors; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D010766:Phosphorylation; D018515:Plant Leaves / Q000737:chemistry; D012333:RNA, Messenger / Q000032:analysis; D013662:Tea / Q000737:chemistry; D014407:Tumor Cells, Cultured
D004791:Enzyme Inhibitors; D061965:Matrix Metalloproteinase Inhibitors; D012333:RNA, Messenger; D013662:Tea; D002392:Catechin; C045651:epigallocatechin gallate; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9