Fu Jen Catholic University

About: Fu Jen Catholic University is a education organization based out in Taipei, Taiwan. It is known for research contribution in the topics: Population & Medicine. The organization has 6842 authors who have published 9512 publications receiving 171005 citations. The organization is also known as: FJU & Fu Jen.

Folate deprivation enhances invasiveness of human colon cancer cells mediated by activation of sonic hedgehog signaling through promoter hypomethylation and cross action with transcription nuclear factor-kappa B pathway.

Abstract: Low folate status is well recognized as one of the metabolic stressors for colorectal cancer carcinogenesis, but its role in colon cancer invasion remains unknown. Activation of the Sonic hedgehog (Shh) signal in interaction with the transcription nuclear factor-kappa B (NF-κB) pathway is crucial for cancer aggressiveness. The aims of this study were to investigate whether and how folate deprivation promotes invasion by colon cancer cells in relation to Shh signaling and NF-κB pathway activation. Cultivation of epithelial colon carcinoma-derived cells (HCT116) in folate-deficient (FD) medium enhanced cellular migration and invasion, in correlation with epithelial-mesenchymal transition (EMT) associated with Snail expression and E-cadherin suppression, increased production of β1 integrin and increased proteolysis by matrix metalloproteinase 2. Blockade of Shh signaling by cyclopamine (CYC) or of NF-κB activation by BAY abolished FD-enhanced EMT and invasion by HCT116 cells. FD cells had 50-80% less intracellular folate, associated with aberrant hypomethylation of the Shh promoter, than control cells, and increased binding of nuclear NF-κB subunit p65 to the Shh promoter region, which coincided with increased Shh expression and protein production of Shh ligand; in addition, the FD-induced Shh signaling targeted Gli1 transcription activator as well as Ptch receptor. The FD-induced Shh induction and activated signaling were blocked by NF-κB inhibitor BAY. Blockade of Shh signaling abrogated FD-promoted NF-κB activation measured by IκBα degradation and by target gene TNFα expression. Taken together, these findings demonstrate that folate deprivation enhanced invasiveness of colon cancer cells mediated by activation of Shh signaling through promoter hypomethylation and cross actions with the NF-κB pathway.

A personalized and integrative comparison-shopping engine and its applications

Abstract: Agents are the catalysts for commerce on the Web today. For example, comparison-shopping agents mediate the interactions between consumers and suppliers in order to yield markets that are more efficient. However, today's shopping agents are price-dominated, unreflective of the nature of supplier/consumer differentiation or the changing course of differentiation over time. This paper aims to tackle this dilemma and advances shopping agents into a stage where both kinds of differentiation are taken into account for enhanced understanding of the realities. We call them personalized and integrative shopping agents. These agents can leverage the interactive power of the Web for a more accurate understanding of consumer's preferences. This paper then presents a comparison-shopping engine that can be easily instantiated to become personalized and integrative shopping agents. This engine comprises of a product/merchant information collector, a consumer behavior extractor, a user profile manager, and an on-line learning personalized ranking module. We have built this engine and instantiated a comparison-shopping system for collecting preliminary evaluation results. The results show that this system is quite promising in overcoming the reality challenges of comparison shopping. In order to strengthen the contributions of this engine, we also gave a fielded application of this engine for personalized travel information discovery and explained the great potentials of this engine for a variety of comparison-shopping tasks.