title: Epigallocatechin-3-O-gallate up-regulates microRNA-let-7b expression by activating 67-kDa laminin receptor signaling in melanoma cells.
abstract: MicroRNAs (miRNAs) are non-coding RNAs involved in various biological processes by regulating their target genes. Green tea polyphenol (-)-epigallocatechin-3-O-gallate (EGCG) inhibits melanoma tumor growth by activating 67-kDa laminin receptor (67LR) signaling. To examine the effect of EGCG on miRNA expression in melanoma cells, we performed miRNA microarray analysis. We showed that EGCG up-regulated miRNA-let-7b expression through 67LR in melanoma cells. The EGCG-induced up-regulation of let-7b led to down-regulation of high mobility group A2 (HMGA2), a target gene related to tumor progression. 67LR-dependent cAMP/protein kinase A (PKA)/protein phosphatase 2A (PP2A) signaling pathway activation was involved in the up-regulation of let-7b expression induced by EGCG. These findings provide a basis for understanding the mechanism of miRNA regulation by EGCG.
authors.affiliation: Division of Applied Biological Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Shuhei
authors.initials: S
authors.lastname: Yamada
authors.affiliation: Division of Applied Biological Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Shuntaro
authors.initials: S
authors.lastname: Tsukamoto
authors.affiliation: Division of Applied Biological Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Division of Applied Biological Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Makio
authors.affiliation: Division of Applied Biological Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Motofumi
authors.initials: M
authors.lastname: Kumazoe
authors.affiliation: Division of Applied Biological Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Shuya
authors.initials: S
authors.lastname: Yamashita
authors.affiliation: Division of Applied Biological Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Tachibana
mesh_terms: D000818:Animals; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D045744:Cell Line, Tumor; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D025743:HMGA2 Protein / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008545:Melanoma / Q000235:genetics* / Q000378:metabolism*; D051379:Mice; D035683:MicroRNAs / Q000235:genetics*; D054648:Protein Phosphatase 2 / Q000378:metabolism; D017474:Receptors, Laminin / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: D025743:HMGA2 Protein; D035683:MicroRNAs; C510624:RPSA protein, human; D017474:Receptors, Laminin; D012269:Ribosomal Proteins; C487931:mirnlet7 microRNA, human; D002392:Catechin; C045651:epigallocatechin gallate; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; D054648:Protein Phosphatase 2