title: Oxygen partial pressure modulates 67-kDa laminin receptor expression, leading to altered activity of the green tea polyphenol, EGCG.
abstract: (-)-Epigallocatechin-3-O-gallate (EGCG) exhibits anti-tumor activity mediated via the 67-kDa laminin receptor (67LR). In this study, we found that 67LR protein levels are reduced by exposure to low O(2) levels (5%), without affecting the expression of HIF-1α. We also found that EGCG-induced anti-cancer activity is abrogated under low O(2) levels (5%) in various cancer cells. Notably, treatment with the proteasome inhibitor, prevented down-regulation of 67LR and restored sensitivity to EGCG under 5% O(2). In summary, 67LR expression is highly sensitive to O(2) partial pressure, and the activity of EGCG can be regulated in cancer cells by O(2) partial pressure.
authors.affiliation: Laboratory of Food Chemistry, Division of Applied Biological Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka, Japan.
authors.forename: Shuntaro
authors.initials: S
authors.lastname: Tsukamoto
authors.forename: Shuya
authors.initials: S
authors.lastname: Yamashita
authors.forename: Yoon Hee
authors.initials: YH
authors.lastname: Kim
authors.forename: Motofumi
authors.initials: M
authors.lastname: Kumazoe
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Huang
authors.forename: Koji
authors.initials: K
authors.lastname: Yamada
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Tachibana
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D001483:Base Sequence; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D017931:DNA Primers / Q000235:genetics; D006367:HeLa Cells; D056945:Hep G2 Cells; D006801:Humans; D000860:Hypoxia / Q000378:metabolism / Q000473:pathology; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism; D008546:Melanoma, Experimental / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D051379:Mice; D010100:Oxygen / Q000378:metabolism*; D061988:Proteasome Inhibitors / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism; D017474:Receptors, Laminin / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D017931:DNA Primers; C497443:Hif1a protein, mouse; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D061988:Proteasome Inhibitors; D017382:Reactive Oxygen Species; D017474:Receptors, Laminin; D002392:Catechin; C045651:epigallocatechin gallate; D010100:Oxygen