12-O-tetradecanoylphorbol-13-acetate-induced invasion/migration of glioblastoma cells through activating PKCα/ERK/NF-κB-dependent MMP-9 expression

• Published in: Journal of cellular physiology Vol. 225; no. 2; pp. 472 - 481
• Main Authors: Lin, Cheng-Wei, Shen, Shing-Chuan, Chien, Chih-Chiang, Yang, Liang-Yo, Shia, Lin-Ting, Chen, Yen-Chou
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.11.2010; Wiley Subscription Services, Inc
• Subjects: Acetic acid; Cell activation; Cell migration; Cytosol; Enzymatic activity; Enzyme activity; Enzymes; Extracellular signal-regulated kinase; Flavonoids; Gene expression; Glioblastoma; Glioblastoma cells; Glioma; Glioma cells; Kaempferol; Kinases; Nuclear transport; Phosphorylation; Protein kinase C; Protein transport; Proteins; siRNA; Transfection; Translocation; Wound healing
• ISSN: 0021-9541; 1097-4652
• DOI: 10.1002/jcp.22226

An increase in MMP‐9 gene expression and enzyme activity with stimulating the migration of GBM8401 glioma cells via wound healing assay by 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) was detected in glioblastoma cells GBM8401. TPA‐induced translocation of protein kinase C (PKC)α from the cytosol to membranes, and migration of GBM8401 elicited by TPA was suppressed by adding the PKCα inhibitors, GF109203X and H7. Activation of extracellular signal‐regulated kinase (ERK) and c‐Jun‐N‐terminal kinase (JNK) by TPA was identified, and TPA‐induced migration and MMP‐9 activity was significantly blocked by ERK inhibitor PD98059 and U0126, but not JNK inhibitor SP600125. Activation of NF‐κB protein p65 nuclear translocation and IκBα protein phosphorylation with increased NF‐κB‐directed luciferase activity by TPA were observed, and these were blocked by the PD98059 and IkB inhibitor BAY117082 accompanied by reducing migration and MMP‐9 activity induced by TPA in GBM8401 cells. Transfection of GBM8401 cells with PKCα siRNA specifically reduced PKCα protein expression with blocking TPA‐induced MMP‐9 activation and migration. Additionally, suppression of TPA‐induced PKCα/ERK/NK‐κB activation, migration, and MMP‐9 activation by flavonoids including kaempferol (Kae; 3,5,7,4′‐tetrahydroxyflavone), luteolin (Lut; 5,7,3′4′‐tetrahydroxyflavone), and wogonin (Wog; 5,7‐dihydroxy‐8‐methoxyflavone) was demonstrated, and structure–activity relationship (SAR) studies showed that hydroxyl (OH) groups at C4′ and C8 are critical for flavonoids' action against MMP‐9 enzyme activation and migration/invasion of glioblastoma cells elicited by TPA. Application of flavonoids to prevent the migration/invasion of glioblastoma cells through blocking PKCα/ERK/NF‐κB activation is first demonstrated herein. J. Cell. Physiol. 225: 472–481, 2010. © 2010 Wiley‐Liss, Inc.