title: Gallic acid inhibits migration and invasion in human osteosarcoma U-2 OS cells through suppressing the matrix metalloproteinase-2/-9, protein kinase B (PKB) and PKC signaling pathways.
abstract: Advanced cancer is a multifactorial disease which complicates treatment if the cancer cells have metastasized calling for the targeting of multiple cellular pathways. Gallic acid (GA) is known to possess multiple pharmacological activity including antitumor effects. This study investigated the mechanisms for the anticancer properties of GA on migration and invasion of human osteosarcoma U-2 OS cells. The migration and invasion in U-2 OS cells were determined by a Boyden chamber transwell assay. The expression levels and activities of MMP-2 and MMP-9 were measured by Western blotting, real-time PCR and gelatin zymography assays. All examined proteins levels from Western blotting indicated that GA decreased the protein levels of GRB2, PI3K, AKT/PKB, PKC, p38, ERK1/2, JNK, NF-κB p65 in U-2 OS cells. GA also inhibited the activities of AKT, IKK and PKC by in vitro kinase assay. GA suppressed the migration and invasive ability of U-2 OS cells, and it decreased MMP-2 and MMP-9 protein and mRNA levels and secreted enzyme activities in vitro. These results suggest that potential signaling pathways of GA-inhibited migration and invasion in U-2 OS cells may be due to down-regulation of PKC, inhibition of mitogen-activated protein kinase (MAPK) and PI3K/AKT, resulting in inhibition of MMP-2 and MMP-9 expressions.
authors.affiliation: Graduate Institute of Chinese Medicine, China Medical University, Taichung 404, Taiwan, ROC.
authors.forename: Ching-Lung
authors.initials: CL
authors.lastname: Liao
authors.forename: Kuang-Chi
authors.initials: KC
authors.lastname: Lai
authors.forename: An-Cheng
authors.initials: AC
authors.lastname: Huang
authors.forename: Jai-Sing
authors.initials: JS
authors.lastname: Yang
authors.forename: Jen-Jyh
authors.initials: JJ
authors.lastname: Lin
authors.forename: Shin-Hwar
authors.initials: SH
authors.lastname: Wu
authors.forename: W
authors.initials: W
authors.lastname: Gibson Wood
authors.forename: Jaung-Geng
authors.initials: JG
authors.lastname: Lin
authors.forename: Jing-Gung
authors.initials: JG
authors.lastname: Chung
mesh_terms: D001483:Base Sequence; D015153:Blotting, Western; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects*; D017931:DNA Primers; D005707:Gallic Acid / Q000494:pharmacology*; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism; D009361:Neoplasm Invasiveness / Q000517:prevention & control*; D011493:Protein Kinase C / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger; D005707:Gallic Acid; D051057:Proto-Oncogene Proteins c-akt; D011493:Protein Kinase C; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9