Phosphorylation ; Porphyromonas gingivalis ; Signal Transduction

Syk Kinase ; Tyrosine/metabolism* ; Phosphorylation

Hippo/YAP signaling is implicated in tumorigenesis and progression of various cancers. By inhibiting a plethora signaling cascades, resveratrol has strong anti-tumorigenic and anti-metastatic activity. In the present study, we demonstrate that resveratrol decreases the expression of YAP target genes. In addition, our data showed that resveratrol attenuates breast cancer cell invasion through the activation of Lats1 and consequent inactivation of YAP. Strikingly, we also demonstrate that resveratrol inactivates RhoA, leading to the activation of Lats1 and induction of YAP phosphorylation. Further, resveratrol in combination with other agents that inactivate RhoA or YAP showed more marked suppression of breast cancer cell invasion compared with single treatment. Collectively, these findings indicate the beneficial effects of resveratrol on breast cancer patients by suppressing the RhoA/Lats1/YAP signaling axis and subsequently inhibiting breast cancer cell invasion.
Breast Neoplasms* ; Breast* ; Carcinogenesis ; Humans ; Phosphorylation

No abstract available.
eIF-2 Kinase* ; HIV-1* ; Phosphorylation

Quercetin, a flavonol, has been reported to exhibit a wide range of biological properties including anti-oxidant and anti-inflammatory activities. However, pharmacological properties of quercetin-3-O-β-D-glucuronide (QG), a glycoside derivative of quercetin, have not been extensively examined. The objective of this study is to elucidate the anti-inflammatory property and underlying mechanism of QG in lipopolysaccharide (LPS)-challenged RAW264.7 macrophage cells in comparison with quercetin. QG significantly suppressed LPS-induced extracellular secretion of pro-inflammatory mediators such as nitric oxide (NO) and PGE2, and pro-inflammatory protein expressions of iNOS and COX-2. To elucidate the underlying mechanism of the anti-inflammatory property of QG, involvement of MAPK signaling pathways was examined. QG significantly attenuated LPS-induced activation of JNK and ERK in concentration-dependent manners with a negligible effect on p38. In conclusion, the present study demonstrates QG exerts anti-inflammatory activity through the suppression of JNK and ERK signaling pathways in LPS-challenged RAW264.7 macrophage cells.
Dinoprostone ; Macrophages ; Nitric Oxide ; Phosphorylation* ; Quercetin

Tyrosine phosphorylation is one of the important protein phosphorylations in eukaryotes responsible for a variety of biological processes including cell signaling transduction, cell migration, and apoptosis. In the study of phosphoproteomics, due to the low stoichiometry of tyrosine phosphorylation (pTyr) proteins and sometimes limited initial sample, traditional phosphoproteomics enrichment technology is inefficient for the enrichment of pTyr peptides. Here, we review the substantial progress in tyrosine phosphoproteomics by preparation of limited amount sample and the newly introduced SH2 superbinder.
Cell Movement ; Peptides ; Phosphorylation ; Technology ; Tyrosine/metabolism*

Protein kinase CK2 is a common, evolutionarily conserved and ubiquitous protein kinase. In recent years, increasing evidences have shown that CK2 has a variety of phosphorylated protein substrates, which play important roles in growth, development and various diseases. Therefore, CK2 may participate in these physiological processes by regulating the phosphorylation of these substrates. This article briefly reviewed the structural characteristics of protein kinase CK2 and its physiological functions in growth, development, immunity, formation of tumor and other diseases, in order to provide knowledge basis for further research on the regulatory mechanism of CK2 and potential applications of its inhibitors.
Casein Kinase II/metabolism* ; Phosphorylation ; Proteins

In several human tumors, signal transducer and activator of transcription 3 (STAT3) and nuclear factor κB (NFκB) are activated and interact; how these STAT3–NFκB complexes are transported to the nucleus is not fully understood. In this study, we found that Rac1 was activated in starved cancer cells and that activated Rac1 coexisted with STAT3 and NFκB. Rac1 knockdown and overexpression of the dominant-negative mutant Rac1N19 inhibited the degradation of IκBα, an inhibitor of NFκB. MG132, an inhibitor of the ubiquitin proteasome pathway, increased the amount of non-phosphorylated IκBα, but not serine-phosphorylated IκBα, indicating that IκBα degradation by Rac1 in starved cancer cells is independent of IκBα serine phosphorylation by IKK. Rac1 knockdown also inhibited the nuclear translocation of STAT3–NFκB complexes, indicating that this translocation requires activated Rac1. We also demonstrated that the mutant STAT3 Y705F could form complexes with NFκB, and these unphosphorylated STAT3–NFκB complexes translocated into the nucleus and upregulated the activity of NFκB in starved cancer cells, suggesting that phosphorylation of STAT3 is not essential for its translocation. To our knowledge, this is the first study demonstrating the crucial role of Rac1 in the function of STAT3–NFκB complexes in starved cancer cells and implies that targeting Rac1 may have future therapeutic significance in cancer therapy.
Humans ; Phosphorylation ; Proteasome Endopeptidase Complex ; Serine ; STAT3 Transcription Factor ; Ubiquitin

Epilepsy is arising from many molecular and biochemical events. In the underlying mechanisms of epilepsy, oxidative stress plays an important role in seizure-induced brain damage and neuronal death. Also epileptic seizures are noted in mitochondrial diseases with problems in oxidative phosphorylation. So oxidative stress is an important emerging cause of seizure-induced neuronal death as well as a result of epileptic seizure event.
Brain ; Epilepsy* ; Mitochondrial Diseases ; Neurons ; Oxidative Phosphorylation ; Oxidative Stress*

In the present study we evaluated the anti-inflammatory potential of 3-hydroxy-4,7-megastigmadien-9-one (Comp) isolated from Ulva pertusa Kjellman, in LPS-stimulated bone marrow-derived dendritic cells (BMDCs). Comp treatment exhibited strong dose dependent inhibition of IL-12 p40 and IL-6 cytokine production with IC₅₀ values of 7.85 ± 0.32 and 7.86 ± 0.18, respectively in LPS-stimulated BMDCs. Treatment of Comp inhibited MAPKs and NF-κB pathways in LPS-stimulated BMDCs by inhibiting the phosphorylation of ERK1/2, JNK1/2, p38 and IκB. Thus, these results suggest that Comp have a significant anti-inflammatory property and affirm further studies concerning the potentials of Comp for medicinal use.
Dendritic Cells ; Interleukin-12 ; Interleukin-6 ; Phosphorylation ; Protein Kinases* ; Ulva*