title: Pinocembrin suppresses TGF-β1-induced epithelial-mesenchymal transition and metastasis of human Y-79 retinoblastoma cells through inactivating αvβ3 integrin/FAK/p38α signaling pathway.
abstract: BACKGROUND
  Pinocembrin is the most abundant flavonoid in propolis. In this study, we investigated the antimetastatic effect of pinocembrin on TGF-β1-induced epithelial-mesenchymal transition (EMT) and metastasis of human Y-79 retinoblastoma cells.
  
  
  RESULTS
  Firstly, the results showed that pinocembrin significantly suppresses the TGF-β1-induced abilities of the invasion and migration of Y-79 cells under non-cytotoxic concentration. Pinocembrin decreased TGF-β1-induced expression of vimentin, N-cadherin, αv and β3 integrin in Y-79 cells. Molecular data also showed pinocembrin inhibits the activation of focal adhesion kinase (FAK) and p38α signal involved in the downregulation of enzyme activities, protein and messenger RNA levels of matrix metalloproteinase-2/9 (MMP-2/-9) induced by TGF-β1. Next, pinocembrin also strongly inhibited the degradation of inhibitor of kappaBα (IκBα) and the nuclear levels of nuclear factor kappa B (NF-κB). Also, a dose-dependent inhibition on the binding ability of NF-κB was further observed under pinocembrin treatment.
  
  
  CONCLUSIONS
  Presented results indicated that pinocembrin inhibits TGF-β1-induced epithelial-mesenchymal transition (EMT) and metastasis of Y-79 cells by inactivating the αvβ3 integrin/FAK/p38α signaling pathway. Thus, our findings point to the anticancer potential of pinocembrin against retinoblastoma cells.
authors.affiliation: Department of Optometry, Chung Hwa University of Medical Technology, Tainan 71703, Taiwan.
authors.forename: Kun-Shiang
authors.initials: KS
authors.lastname: Chen
authors.affiliation: Department of Medical Technology, Kaohsiung Veterans General Hospital Tainan Branch, Tainan 71051, Taiwan ; Department of Medical Laboratory Science and Biotechnology and Graduate Institute of Biological Technology, Chung Hwa University of Medical Technology, Tainan 71703, Taiwan.
authors.forename: Ming-Der
authors.initials: MD
authors.lastname: Shi
authors.affiliation: Department of Orthopaedic Surgery, Chi Mei Medical Center, Tainan 71067, Taiwan.
authors.forename: Chi-Sheng
authors.initials: CS
authors.lastname: Chien
authors.affiliation: Department of Food Nutrition, Chung Hwa University of Medical Technology, Tainan 71703, Taiwan ; Department of Biological Science and Technology and Graduate Institute of Biomedical Science, Chung Hwa University of Medical Technology, Tainan 71703, Taiwan.
authors.forename: Yuan-Wei
authors.initials: YW
authors.lastname: Shih
keywords: Invasion; Migration; Pinocembrin; TGF-β1; αv and β3 integrin