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Lung cancer is one of the most common malignancies in the world and its metastasis is the major cause of death in cancer patients. Acacetin (5,7-dihydroxy-4'-methoxyflavone), a flavonoid compound, has anti-peroxidative and anti-inflammatory effects. The effect of acacetin on invasion and migration in human NSCLC A549 cells was investigated. First, the result demonstrated acacetin could exhibit an inhibitory effect on the abilities of the adhesion, morphology/actin cytoskeleton arrangement, invasion, and migration by cell-matrix adhesion assay, immunofluorescence assay, Boyden chamber assay, and wound-healing assay. Molecular data showed that the effect of acacetin in A549 cells might be mediated via sustained inactivation of the phosphorylation of mixed-lineage protein kinase 3 (MLK3), mitogen-activated protein kinase kinases 3/6 (MKK3/6), and p38α MAPK signal involved in the downregulation of the expressions of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), and urokinase-type plasminogen activator (u-PA). Next, acacetin significantly decreased in the phosphorylation and degradation of inhibitor of kappaBα (IκBα), and the nuclear levels of nuclear factor kappa B (NF-κB), c-Fos, and c-Jun. Also, the treatment with acacetin to A549 cells also leads to a concentration-dependent inhibition on the binding abilities of NF-κB and activator protein-1 (AP-1). Furthermore, the treatment of specific inhibitor for p38 MAPK (SB203580) to A549 cells could cause reduced activities of MMP-2/9 and u-PA. In addition, acacetin significantly decreased the levels of phospho-p38α MAPK, MMP-2/9, and u-PA in p38α-cDNA-transfected cells concomitantly with a marked reduction on cell invasion and migration. Our results revealed the anti-migration and anti-invasion effects of acacetin, which may act as a promising therapeutic agent for the treatment of lung cancer.

Purpose -This study proposes integrating the perceived risk and social influence literatures on online group buying (OGB) intentions with the basic TAM variables (perceived usefulness and perceived ease of use). Design/methodology/approach -Based on an empirical survey of 304 online adopters of OGB in Taiwan, the paper uses structural equation modeling to confirm the research model. Findings -The results reveal that perceived critical mass had the largest total effect on intention to use group buying websites. The findings also indicate that perceived usefulness and a sense of virtual community (SOVC) have significant effect on OGB intention. In addition, both perceived ease of use and website quality influence perceived usefulness. As expected, perceived risk has negative effect on OGB intention. Research limitations/implications -This study only considered buying intention with regard to foodstuffs, and it is unclear whether these analytical results can be generalized to other items. Further research could apply this model to examine group coupons (such as discount vouchers for restaurants). Practical implications -To sustain a successful group buying website, attention must be paid to enhancing user's SOVC, enlarging the critical mass, and lowering the perceived risk. Practitioners can apply the findings of this study to focus on the determinants of success for their online shopping websites. Originality/value -Theoretically, while drawing upon TRA studies, this paper provides a model that is capable of lending an understanding of the determinants of OGB intention. From a managerial perspective, the findings indicate that webmasters can improve or manage website members' buying intentions by increasing the sense of virtual community and critical mass.

BackgroundPinocembrin 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.ResultsFirstly, 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.ConclusionsPresented 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.

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