• Asian Pacific Journal of Cancer Prevention
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• v.17 no.6
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• pp.2735-2739
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• 2016

Curcumin, is a polyphenol from Curcuma longa (turmeric plant), is a polyphenol that belongs to the ginger family which has long been used in Ayurveda medicines to treat various diseases such as asthma, anorexia, coughing, hepatic diseases, diabetes, heart diseases, wound healing and Alzheimer's. Various studies have shown that curcumin has anti-infectious, anti-inflammatory, anti-oxidant, hepatoprotective, thrombosuppressive, cardio protective, anti-arthritic, chemo preventive and anti-carcinogenic activities. It may suppress both initiation and progression stages of cancer. Anticancer activity of curcumin is due to negative regulation of inflammatory cytokines, transcription factors, protein kinases, reactive oxygen species (ROS) and oncogenes. This review focuses on the different targets of curcumin to treat cancer.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.481-487
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• 2007

Toll-like receptors (TLRs) induce innate immune responses that are essential for host defenses against invading microbial pathogens, thus leading to the activation of adaptive immune responses. In general, TLRs have two major downstream signaling pathways: the MyD88- and TRIF-dependent pathways, which lead to the activation of $NF-{\kappa}B$ and IRF3. Numerous studies have demonstrated that certain phytochemicals possessing anti-inflammatory effects inhibit $NF-{\kappa}B$ activation induced by pro-inflammatory stimuli, including lipopolysaccharides and $TNF{\alpha}$. However, the direct molecular targets for such anti-inflammatory phytochemicals have not been fully identified. Identifying the direct targets of phytochemicals within the TLR pathways is important because the activation of TLRs by pro-inflammatory stimuli can induce inflammatory responses that are the key etiological conditions in the development of many chronic inflammatory diseases. In this paper we discuss the molecular targets of resveratrol, (-)-epigallocatechin-3-gallate (EGCG), and curcumin in the TLR signaling pathways. Resveratrol specifically inhibited the TRIF pathway in TLR3 and TLR4 signaling, by targetting TBK1 and RIP1 in the TRIF complex. Furthermore, EGCG suppressed the activation of IRF3 by targetting TBK1 in the TRIF-dependent signaling pathways. In contrast, the molecular target of curcumin within the TLR signaling pathways is the receptor itself, in addition to $IKK{\beta}$. Together, certain dietary phytochemicals can modulate TLR-derived signaling and inflammatory target gene expression, and in turn, alter susceptibility to microbial infection and chronic inflammatory diseases.

• Korean Journal of Food Science and Technology
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• v.41 no.5
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• pp.477-482
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• 2009

Toll-like receptors (TLRs) play a critical role in the induction of innate immune responses that are essential for host defense against invading microbial pathogens. In general, TLRs have two major downstream signaling pathways, namely MyD88- and TRIF-dependent pathways, leading to the activation of nuclear factor-${\kappa}B$ (NF-${\kappa}B$) and interferon regulatory factor 3 (IRF3) and the expression of inflammatory mediators. TLR4 dimerization is required for the activation of downstream signaling pathways and may be one of the first lines of regulation in activating TLR-mediated signaling pathways. In this paper, the molecular targets of curcumin, 6-shogaol, and cinnamaldehyde in TLR signaling pathways will be discussed. Curcumin, 6-shogaol, and cinnamaldehyde with ${\alpha},{\beta}$-unsaturated carbonyl groups inhibit the dimerization of TLR4 induced by lipopolysaccharide, resulting in the downregulation of NF-${\kappa}B$ and IRF3. These results suggest that phytochemicals with the structural motif conferring Michael addition inhibit TLR4 dimerization, suggesting a novel mechanism for the anti-inflammatory activity of phytochemicals.

• Journal of Digestive Cancer Research
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• v.4 no.2
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• pp.64-76
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• 2016

The step-wise process of colorectal carcinogenesis from aberrant crypt foci, adenoma to adenocarcinoma, is relatively suitable for chemopreventive intervention. Accumulated evidences have revealed that maintaining an undifferentiated state (stemness), inflammation, and oxidative stress play important roles in this colon carcinogenesis process. However, appropriate molecular targets that are applicable to chemopreventive intervention regarding those three factors are still unclear. In this review, we summarized appropriate molecular targets by identification and validation of the prospective targets from a comprehensive overview of data that showed colon cancer preventive effects in clinical trials, epidemiological studies and basic research. We first selected a study that used aspirin, statins and metformin from FDA approved drugs, and epigallocatechin-gallate and curcumin from natural compounds as potential chemopreventive agents against colon cancer because these agents are considered to be promising chemopreventive agents. Experimental and observational data revealed that there are common target molecules in these potential chemopreventive agents: T-cell factor/lymphoid enhancer factor (TCF/LEF), nuclear factor-&B (NF-κB) and nuclear factor-erythroid 2-related factor 2(NRF2). Moreover, these targets, TCF/LEF, NF-κB and NRF2, have been also indicated to suppress maintenance of the undifferentiated state, inflammation and oxidative stress, respectively. In the near future, novel promising candidate agents for colon cancer chemoprevention could be identified by integral evaluation of their effects on these three transcriptional activities.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.263-269
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• 2008

Hydrazinocurcumin (HC), a synthetic derivative of curcumin, has been reported to inhibit angiogenesis via unknown mechanisms. Understanding the molecular mechanisms of the drug's action is important for the development of improved compounds with better pharmacological properties. A genome-wide drug-induced haploinsufficiency screening of fission yeast gene deletion mutants has been applied to identify drug targets of HC. As a first step, the 50% inhibition concentration $(IC_{50})$ of HC was determined to be $2.2{\mu}M$. The initial screening of 4,158 mutants in 384-well plates using robotics was performed at concentrations of 2, 3, and $4{\mu}M$. A second screening was performed to detect sensitivity to HC on the plates. The first screening revealed 178 candidates, and the second screening resulted in 13 candidates, following the elimination of 165 false positives. Final filtering of the condition-dependent haploinsufficient genes gave eight target genes. Analysis of the specific targets of HC has shown that they are related to septum formation and the general transcription processes, which may be related to histone acetyltransferase. The target mutants showed 65% growth inhibition in response to HC compared with wild-type controls, as shown by liquid culture assay.