Suppressive effects of tea polyphenol and conformational changes with receptor for advanced glycation end products (RAGE) expression in human hepatoma cells.
OBJECTIVE
It is reported that polyphenol is associated with low risk of hepatoma and that RAGE (receptor for advanced glycation end products) is important for cancer invasion.


METHODS
Effects of teapolyphenol, EGCG (epigallocatechin-3-gallate) were studied. Proliferation of on human hepatoma cells, HLF, was measured with the use of WST-1 colorimetric assay. Cell invasion was analyzed by the Matrigel invasion assay. Morphology and immunohistological staining of expression of RAGE were also performed.


RESULTS
Proliferation was inhibited with the addition of EGCG in a dose-dependent manner. EGCG (200 mumol/L) produced a profound growth suppression of HLF cells (24.5%). Cell invasion was also inhibited with preincubation of 100 mumol/L of EGCG (10.2%). In addition to the antitumor effects, neurite-like conformational changes of HLF cells were observed. Addition of EGCG (100 mumol/L) showed the expression of RAGE on cell surface in accordance to the morphological changes.


CONCLUSIONS
The pathway associated to cell movement might be activated with RAGE expression. Although EGCG inhibits the growth and invasion, the cells which expressed RAGE seem to survive. Thus, the enrollment of RAGE should be analyzed to clarify the mechanisms of cancer resistance.
Takada
Moriatsu
M
First Department of Surgery, Kobe University School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. moriatsu@med.kobe-u.ac.jp
Ku
Yonson
Y
Toyama
Hirochika
H
Suzuki
Yasuyuki
Y
Kuroda
Yoshikazu
Y
D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D006528:Carcinoma, Hepatocellular / Q000473:pathology*; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology*; D009361:Neoplasm Invasiveness / Q000473:pathology; D016501:Neurites / Q000187:drug effects / Q000473:pathology; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic / Q000187:drug effects*; D013662:Tea; D014407:Tumor Cells, Cultured / Q000473:pathology*
D000972:Antineoplastic Agents, Phytogenic; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic; D013662:Tea; D002392:Catechin; C045651:epigallocatechin gallate