Showing papers by "Michael Karin published in 2011"

Inflammation meets cancer, with NF-κB as the matchmaker

Abstract: Inflammation is a fundamental protective response that sometimes goes awry and becomes a major cofactor in the pathogenesis of many chronic human diseases, including cancer. Here we review the evolutionary relationship and opposing functions of the transcription factor NF-κB in inflammation and cancer. Although it seems to fulfill a distinctly tumor-promoting role in many types of cancer, NF-κB has a confounding role in certain tumors. Understanding the activity and function of NF-κB in the context of tumorigenesis is critical for its successful taming, an important challenge for modern cancer biology.

NF-κB and STAT3 - key players in liver inflammation and cancer.

Abstract: Hepatocellular carcinoma (HCC), the major form of primary liver cancer, is one of the most deadly human cancers. The pathogenesis of HCC is frequently linked with continuous hepatocyte death, inflammatory cell infiltration and compensatory liver regeneration. Understanding the molecular signaling pathways driving or mediating these processes during liver tumorigenesis is important for the identification of novel therapeutic targets for this dreadful disease. The classical IKKβ-dependent NF-κB signaling pathway has been shown to promote hepatocyte survival in both developing and adult livers. In addition, it also plays a crucial role in liver inflammatory responses by controlling the expression of an array of growth factors and cytokines. One of these cytokines is IL-6, which is best known for its role in the liver acute phase response. IL-6 exerts many of its functions via activation of STAT3, a transcription factor found to be important for HCC development. This review will focus on recent studies on the roles of NF-κB and STAT3 in liver cancer. Interactions between the two pathways and their potential as therapeutic targets will also be discussed.

Tumour-infiltrating regulatory T cells stimulate mammary cancer metastasis through RANKL–RANK signalling

Abstract: In a mouse model of ErbB-driven mammary tumours, Tan et al. find a role for RANKL (receptor activator of nuclear factor-κB ligand) in the formation of lung metastases. RANKL is produced by regulatory T cells infiltrating the primary tumours, and acts through its receptor RANK, which is expressed on the cancer cells. Targeting RANKL may therefore prove useful in reducing breast cancer metastases. In a mouse model of Erbb2-driven mammary tumours, this study finds a role for RANKL in the formation of lung metastases. RANKL is produced by regulatory T cells infiltrating the primary tumours and acts via its receptor RANK expressed on the cancer cells. Targeting RANKL may therefore prove useful in reducing breast cancer metastases. Inflammatory mechanisms influence tumorigenesis and metastatic progression even in cancers whose aetiology does not involve pre-existing inflammation or infection, such as breast and prostate cancers1. For instance, prostate cancer metastasis is associated with the infiltration of lymphocytes into advanced tumours and the upregulation of two tumour-necrosis-factor family members: receptor activator of nuclear factor-κB (RANK) ligand (RANKL) and lymphotoxin2. But the source of RANKL and its role in metastasis have not been established. RANKL and its receptor RANK control the proliferation of mammary lobuloalveolar cells during pregnancy3 through inhibitor of nuclear factor-κB (IκB) kinase-α (IKK-α)4, a protein kinase that is needed for the self-renewal of mammary cancer progenitors5 and for prostate cancer metastasis2. We therefore examined whether RANKL, RANK and IKK-α are also involved in mammary/breast cancer metastasis. Indeed, RANK signalling in mammary carcinoma cells that overexpress the proto-oncogene Erbb2 (also known as Neu)6, which is frequently amplified in metastatic human breast cancers7,8, was important for pulmonary metastasis. Metastatic spread of Erbb2-transformed carcinoma cells also required CD4+CD25+ T cells, whose major pro-metastatic function was RANKL production. Most RANKL-producing T cells expressed forkhead box P3 (FOXP3), a transcription factor produced by regulatory T cells, and were located next to smooth muscle actin (SMA)+ stromal cells in mouse and human breast cancers. The dependence of pulmonary metastasis on T cells was replaceable by exogenous RANKL, which also stimulated pulmonary metastasis of RANK+ human breast cancer cells. These results are consistent with the adverse impact of tumour-infiltrating CD4+ or FOXP3+ T cells on human breast cancer prognosis9,10 and suggest that the targeting of RANKL–RANK can be used in conjunction with the therapeutic elimination of primary breast tumours to prevent recurrent metastatic disease.

Inflammatory cytokines in cancer: tumour necrosis factor and interleukin 6 take the stage

Abstract: Up to 20% of all cancers arise in association with chronic inflammation and most, if not all, solid tumours contain inflammatory infiltrates. Immune cells have a broad impact on tumour initiation, growth and progression and many of these effects are mediated by proinflammatory cytokines. Among these cytokines, the pro-tumourogenic function of tumour necrosis factor (TNF) and interleukin 6 (IL-6) is well established. The role of TNF and IL-6 as master regulators of tumour-associated inflammation and tumourigenesis makes them attractive targets for adjuvant treatment in cancer.

Expanding TRAF function: TRAF3 as a tri-faced immune regulator

Abstract: Tumour necrosis factor receptor (TNFR)-associated factor (TRAF) proteins are essential components of signalling pathways activated by TNFR or Toll-like receptor (TLR) family members. Acting alone or in combination, the seven known TRAFs control many biological processes, including cytokine production and cell survival. The function of one TRAF in particular, TRAF3, remained elusive for many years. Recent work has revealed that TRAF3 is a highly versatile regulator that positively controls type I interferon production, but negatively regulates mitogen-activated protein kinase activation and alternative nuclear factor-κB signalling. In this Review, we discuss our current understanding of the role of TRAF3 in TNFR and TLR signalling pathways, and its role in disease.

Fibroblast-specific protein 1 identifies an inflammatory subpopulation of macrophages in the liver

Abstract: Cirrhosis is the end result of chronic liver disease. Hepatic stellate cells (HSC) are believed to be the major source of collagen-producing myofibroblasts in cirrhotic livers. Portal fibroblasts, bone marrow-derived cells, and epithelial to mesenchymal transition (EMT) might also contribute to the myofibroblast population in damaged livers. Fibroblast-specific protein 1 (FSP1, also called S100A4) is considered a marker of fibroblasts in different organs undergoing tissue remodeling and is used to identify fibroblasts derived from EMT in several organs including the liver. The aim of this study was to characterize FSP1-positive cells in human and experimental liver disease. FSP1-positive cells were increased in human and mouse experimental liver injury including liver cancer. However, FSP1 was not expressed by HSC or type I collagen-producing fibroblasts. Likewise, FSP1-positive cells did not express classical myofibroblast markers, including αSMA and desmin, and were not myofibroblast precursors in injured livers as evaluated by genetic lineage tracing experiments. Surprisingly, FSP1-positive cells expressed F4/80 and other markers of the myeloid-monocytic lineage as evaluated by double immunofluorescence staining, cell fate tracking, flow cytometry, and transcriptional profiling. Similar results were obtained for bone marrow-derived and peritoneal macrophages. FSP1-positive cells were characterized by increased expression of COX2, osteopontin, inflammatory cytokines, and chemokines but reduced expression of MMP3 and TIMP3 compared with Kupffer cells/macrophages. These findings suggest that FSP1 is a marker of a specific subset of inflammatory macrophages in liver injury, fibrosis, and cancer.

Crystal structure of inhibitor of κB kinase β

Abstract: Inhibitor of κB (IκB) kinase (IKK) phosphorylates IκB proteins, leading to their degradation and the liberation of nuclear factor κB for gene transcription. Here we report the crystal structure of IKKβ in complex with an inhibitor, at a resolution of 3.6 A. The structure reveals a trimodular architecture comprising the kinase domain, a ubiquitin-like domain (ULD) and an elongated, α-helical scaffold/dimerization domain (SDD). Unexpectedly, the predicted leucine zipper and helix–loop–helix motifs do not form these structures but are part of the SDD. The ULD and SDD mediate a critical interaction with IκBα that restricts substrate specificity, and the ULD is also required for catalytic activity. The SDD mediates IKKβ dimerization, but dimerization per se is not important for maintaining IKKβ activity and instead is required for IKKβ activation. Other IKK family members, IKKα, TBK1 and IKK-i, may have a similar trimodular architecture and function. IKK (inhibitor of κB kinase) is an important element in the activation of nuclear factor κB (NF-κB) transcription factors — master regulators of inflammatory, immune and apoptotic responses. Here Wu and colleagues describe the long awaited X-ray structure of a member of the IKK family in combination with an inhibitor. They show that IKKβ has a tri-molecular architecture that contains the kinase domain, a ubiquitin-like domain and an extended scaffolding and dimerization domain, and discuss the functional implications.

Constitutive intestinal NF-κB does not trigger destructive inflammation unless accompanied by MAPK activation.

Abstract: Nuclear factor (NF)-κB, activated by IκB kinase (IKK), is a key regulator of inflammation, innate immunity, and tissue integrity. NF-κB and one of its main activators and transcriptional targets, tumor necrosis factor (TNF), are up-regulated in many inflammatory diseases that are accompanied by tissue destruction. The etiology of many inflammatory diseases is poorly understood, but often depends on genetic factors and environmental triggers that affect NF-κB and related pathways. It is unknown, however, whether persistent NF-κB activation is sufficient for driving symptomatic chronic inflammation and tissue damage. To address this question, we generated IKKβ(EE)(IEC) mice, which express a constitutively active form of IKKβ in intestinal epithelial cell (IECs). IKKβ(EE)(IEC) mice exhibit NF-κB activation in IECs and express copious amounts of inflammatory chemokines, but only small amounts of TNF. Although IKKβ(EE)(IEC) mice exhibit inflammatory cell infiltration in the lamina propria (LP) of their small intestine, they do not manifest tissue damage. Yet, upon challenge with relatively mild immune and microbial stimuli, IKKβ(EE)(IEC) mice succumb to destructive acute inflammation accompanied by enterocyte apoptosis, intestinal barrier disruption, and bacterial translocation. Inflammation is driven by massive TNF production, which requires additional activation of p38 and extracellular-signal-regulated kinase mitogen-activated protein kinases (MAPKs).

Developmental factor IRF6 exhibits tumor suppressor activity in squamous cell carcinomas

Abstract: The transcription factor interferon regulatory factor 6 (IRF6) regulates craniofacial development and epidermal proliferation. We recently showed that IRF6 is a component of a regulatory feedback loop that controls the proliferative potential of epidermal cells. IRF6 is transcriptionally activated by p63 and induces its proteasome-mediated down-regulation, thereby limiting keratinocyte proliferative potential. We hypothesized that IRF6 may also be involved in skin carcinogenesis. Hence, we analyzed IRF6 expression in a large series of squamous cell carcinomas (SCCs) and found a strong down-regulation of IRF6 that correlated with tumor invasive and differentiation status. IRF6 down-regulation in SCC cell lines and primary tumors correlates with methylation on a CpG dinucleotide island located in its promoter region. To identify the molecular mechanisms regulating IRF6 potential tumor suppressive activity, we performed a genome-wide analysis by combining ChIP sequencing for IRF6 binding sites and gene expression profiling in primary human keratinocytes after siRNA-mediated IRF6 depletion. We observed dysregulation of cell cycle-related genes and genes involved in differentiation, cell adhesion, and cell–cell contact. Many of these genes were direct IRF6 targets. We also performed in vitro invasion assays showing that IRF6 down-regulation promotes invasive behavior and that reintroduction of IRF6 into SCC cells strongly inhibits cell growth. These results indicate a function for IRF6 in suppression of tumorigenesis in stratified epithelia.

IL-1β-driven neutrophilia preserves antibacterial defense in the absence of the kinase IKKβ.

Abstract: Transcription factor NF-κB and its activating kinase IKKβ are associated with inflammation and are believed to be critical for innate immunity. Despite the likelihood of immune suppression, pharmacological blockade of IKKβ-NF-κB has been considered as a therapeutic strategy. However, we found neutrophilia in mice with inducible deletion of IKKβ (Ikkβ(Δ) mice). These mice had hyperproliferative granulocyte-macrophage progenitors and pregranulocytes and a prolonged lifespan of mature neutrophils that correlated with the induction of genes encoding prosurvival molecules. Deletion of interleukin 1 receptor 1 (IL-1R1) in Ikkβ(Δ) mice normalized blood cellularity and prevented neutrophil-driven inflammation. However, Ikkβ(Δ)Il1r1(-/-) mice, unlike Ikkβ(Δ) mice, were highly susceptible to bacterial infection, which indicated that signaling via IKKβ-NF-κB or IL-1R1 can maintain antimicrobial defenses in each other's absence, whereas inactivation of both pathways severely compromises innate immunity.

Transmembrane tumour necrosis factor is neuroprotective and regulates experimental autoimmune encephalomyelitis via neuronal nuclear factor-κB

Abstract: Tumour necrosis factor mediates chronic inflammatory pathologies including those affecting the central nervous system, but non-selective tumour necrosis factor inhibitors exacerbate multiple sclerosis. In addition, TNF receptor SF1A , which encodes one of the tumour necrosis factor receptors, has recently been identified as a multiple sclerosis susceptibility locus in genome-wide association studies in large patient cohorts. These clinical data have emphasized the need for a better understanding of the beneficial effects of tumour necrosis factor during central nervous system inflammation. In this study, we present evidence that the soluble and transmembrane forms of tumour necrosis factor exert opposing deleterious and beneficial effects, respectively, in a multiple sclerosis model. We compared the effects, in experimental autoimmune encephalomyelitis, of selectively inhibiting soluble tumour necrosis factor, and of both soluble and transmembrane tumour necrosis factor. Blocking the action of soluble tumour necrosis factor, but not of soluble tumour necrosis factor and transmembrane tumour necrosis factor, protected mice against the clinical symptoms of experimental autoimmune encephalomyelitis. Therapeutic benefit was independent of changes in antigen-specific immune responses and focal inflammatory spinal cord lesions, but was associated with reduced overall central nervous system immunoreactivity, increased expression of neuroprotective molecules, and was dependent upon the activity of neuronal nuclear factor-κB, a downstream mediator of neuroprotective tumour necrosis factor/tumour necrosis factor receptor signalling, because mice lacking IκB kinase β in glutamatergic neurons were not protected by soluble tumour necrosis factor blockade. Furthermore, blocking the action of soluble tumour necrosis factor, but not of soluble tumour necrosis factor and transmembrane tumour necrosis factor, protected neurons in astrocyte–neuron co-cultures against glucose deprivation, an in vitro neurodegeneration model relevant for multiple sclerosis, and this was dependent upon contact between the two cell types. Our results show that soluble tumour necrosis factor promotes central nervous system inflammation, while transmembrane tumour necrosis factor is neuroprotective, and suggest that selective inhibition of soluble tumour necrosis factor may provide a new way forward for the treatment of multiple sclerosis and possibly other inflammatory central nervous system disorders. * Abbreviations : EAE : experimental autoimmune encephalomyelitis FLIP : FLICE-inhibitory protein IKKβ : IκB kinase β IKKβF/F : loxP-flanked Ikbkb MOG35–55 : myelin oligodendrocyte glycoprotein peptide 35–55 NF-κB : nuclear factor-κB RT-PCR : reverse transcription-polymerase chain reaction TNF : tumour necrosis factor

Role of TLR2-dependent inflammation in metastatic progression.

Abstract: Inflammation is a part of the host defense system, which provides protection against invading pathogens. However, it has become increasingly clear that inflammation can be evoked by endogenous mediators through Toll-like receptors (TLRs) to enhance tumor progression and metastasis. Here, we discuss the roles of TLR-mediated inflammation in tumor progression and the mechanisms through which it accomplishes this pathogenic function.

Crystal structure of inhibitor of kappaB kinase beta.

Abstract: Inhibitor of {kappa}B (I{kappa}B) kinase (IKK) phosphorylates I{kappa}B proteins, leading to their degradation and the liberation of nuclear factor {kappa}B for gene transcription. Here we report the crystal structure of IKK{beta} in complex with an inhibitor, at a resolution of 3.6 {angstrom}. The structure reveals a trimodular architecture comprising the kinase domain, a ubiquitin-like domain (ULD) and an elongated, {alpha}-helical scaffold/dimerization domain (SDD). Unexpectedly, the predicted leucine zipper and helix-loop-helix motifs do not form these structures but are part of the SDD. The ULD and SDD mediate a critical interaction with I{kappa}B{alpha} that restricts substrate specificity, and the ULD is also required for catalytic activity. The SDD mediates IKK{beta} dimerization, but dimerization per se is not important for maintaining IKK{beta} activity and instead is required for IKK{beta} activation. Other IKK family members, IKK{alpha}, TBK1 and IKK-i, may have a similar trimodular architecture and function.

Transcriptional regulation of the Th17 immune response by IKKα

Abstract: Th17 cells are a subset of T cells that play crucial roles in the pathogenesis of many inflammatory diseases. We report here the identification of IKKα (inhibitor of NF-κB kinase-α) as a key transcriptional regulator of the Th17 lineage. T cells expressing a nonactivatable form of IKKα were significantly compromised in their ability to produce IL-17 and to initiate neural inflammation. IKKα is present in the nuclei of resting CD4+ T cells. Upon Th17 differentiation, IKKα selectively associated with the Il17a locus, and promoted its histone H3 phosphorylation and transcriptional activation in a NF-κB–independent manner. These findings indicate that nuclear IKKα maintains the Th17 phenotype by activating the Il17a gene.

IKKβ regulates essential functions of the vascular endothelium through kinase-dependent and -independent pathways

Abstract: Vascular endothelium provides a selective barrier between the blood and tissues, participates in wound healing and angiogenesis, and regulates tissue recruitment of inflammatory cells. Nuclear factor (NF)-κB transcription factors are pivotal regulators of survival and inflammation, and have been suggested as potential therapeutic targets in cancer and inflammatory diseases. Here we show that mice lacking IKKβ, the primary kinase mediating NF-κB activation, are smaller than littermates and born at less than the expected Mendelian frequency in association with hypotrophic and hypovascular placentae. IKKβ-deleted endothelium manifests increased vascular permeability and reduced migration. Surprisingly, we find that these defects result from loss of kinase-independent effects of IKKβ on activation of the serine-threonine kinase, Akt. Together, these data demonstrate essential roles for IKKβ in regulating endothelial permeability and migration, as well as an unanticipated connection between IKKβ and Akt signalling.

JNK-1 deficiency limits macrophage-mediated antigen-induced arthritis.

Abstract: Objective To elucidate the nonredundant roles of JNK-1 and JNK-2 in antigen-induced arthritis (AIA). Methods Mice that were genetically disrupted in Jnk1 or Jnk2 were primed by injection of methylated bovine serum albumin (mBSA) in Freund's complete adjuvant and then challenged on day 21 by intraarticular injection of mBSA into the right knee. Bone marrow chimeras were generated and similarly treated. Joints were harvested and prepared for histologic assessment. T cell responses were verified by cytokine and proliferation responses, and relative immunoglobulin responses were measured by enzyme-linked immunosorbent assay. Cytokine messenger RNA expression levels were measured by quantitative polymerase chain reaction analysis. Thioglycollate-elicited and zymosan A–elicited macrophage recruitment was tested in vivo, and cell migration was tested in vitro. The peptide inhibitor D-JNKi was injected daily starting 4 days after intraarticular injection of mBSA into wild-type (WT) mice, and inflammation was scored histologically. Results JNK-1–deficient, but not JNK-2–deficient, mice had a reduction in inflammatory cell infiltration and joint damage. This effect was primarily restricted to hematopoietic cells, but B and T cell responses were preserved in mBSA-injected mice. JNK-1–deficient macrophages produced cytokines and chemokines at a level comparable to that in their WT counterparts. However, macrophage migration was impaired in vivo and in vitro. Targeting JNK with the peptide inhibitor D-JNKi dramatically reduced inflammation and joint destruction in WT mice. Conclusion AIA is dependent on JNK-1, but not JNK-2. JNK-1 is a promising molecular target for reducing autoimmune inflammation, since its inhibition impairs macrophage migration.

Cell-Selective Inhibition of NF-κB Signaling Improves Therapeutic Index in a Melanoma Chemotherapy Model

Abstract: The transcription factor NF-κB promotes the survival of cancer cells exposed to doxorubicin and other chemotherapeutic agents. IκB kinase is essential for chemotherapy-induced NF-κB activation and considered a prime target for anticancer treatment. An IκB kinase inhibitor sensitized human melanoma xenografts in mice to killing by doxorubicin yet also exacerbated treatment toxicity in the host animals. By using mouse models that simulate cell-selective targeting, we found that impaired NF-κB activation in melanoma and host myeloid cells accounts for therapeutic and adverse effects, respectively. Ablation of tumor-intrinsic NF-κB activity resulted in apoptosis-driven tumor regression after treatment with doxorubicin. By contrast, chemotherapy in mice with myeloid-specific loss of NF-κB activation led to a massive intratumoral recruitment of interleukin-1β–producing neutrophils and necrotic tumor lesions, a condition associated with increased host mortality but not accompanied by tumor regression. Therefore, a molecular target-based therapy may be steered toward different clinical outcomes depending on the drug's cell-specific effects. Significance: Our findings show that the IκB kinase–NF-κB signaling pathway is important for both promoting treatment resistance and preventing host toxicity in cancer chemotherapy; however, the two functions are exerted by distinct cell type–specific mechanisms and can therefore be selectively targeted to achieve an improved therapeutic outcome. Cancer Discovery; 1(6) ; 496–507. ©2011 AACR . Read the Commentary on this article by Aggarwal and Sung, [p. 469][1] This article is highlighted in the In This Issue feature, [p. 457][2] [1]: /lookup/volpage/1/469?iss=6 [2]: /lookup/volpage/1/457?iss=6

Design and characterization of a potent and selective dual ATP- and substrate-competitive subnanomolar bidentate c-Jun N-terminal kinase (JNK) inhibitor.

Abstract: c-Jun N-terminal kinases (JNKs) represent valuable targets in the development of new therapies. Present on the surface of JNK is a binding pocket for substrates and the scaffolding protein JIP1 in close proximity to the ATP binding pocket. We propose that bidentate compounds linking the binding energies of weakly interacting ATP and substrate mimetics could result in potent and selective JNK inhibitors. We describe here a bidentate molecule, 19, designed against JNK. 19 inhibits JNK kinase activity (IC50 = 18 nM; Ki = 1.5 nM) and JNK/substrate association in a displacement assay (IC50 = 46 nM; Ki = 2 nM). Our data demonstrate that 19 targets for the ATP and substrate-binding sites on JNK concurrently. Finally, compound 19 successfully inhibits JNK in a variety of cell-based experiments, as well as in vivo where it is shown to protect against Jo-2 induced liver damage and improve glucose tolerance in diabetic mice.

IKK-β-mediated myeloid cell activation exacerbates inflammation and inhibits recovery after spinal cord injury.

Abstract: Traumatic spinal cord injury (SCI) is followed by massive infiltration and activation of myeloid cells such as neutrophils and macrophages, but the functions of these cells are controversial. In this study, our objective was to elucidate the in vivo role of a signaling pathway involved in activation of these innate immune cells in SCI using myeloid cell-specific IκB kinase (IKK)-β conditional knockout (ikkβΔmye) mice. In these mice, the ikkβ gene has been specifically deleted from myeloid cells, compromising their in vivo IKK/NF-κB-dependent activation. We found that ikkβΔmye mice had significantly reduced neutrophil and macrophage infiltrations after SCI compared to ikkβ(+/+) controls. SCI-induced proinflammatory gene expression was also reduced in ikkβΔmye mice. Reduced neuroinflammation in ikkβΔmye mice was accompanied by attenuated neuronal loss and behavioral deficits in motor activity. In addition, the SCI-induced expression of CXC ligand 1 was reduced in ikkβΔmye mice, which may be responsible for the reduced neutrophil infiltration in these mice. Our data demonstrate that IKK-β-dependent myeloid cell activation potentiates neuroinflammation and neuronal damage after SCI.

NF-κB, IκB Kinase and Interacting Signal Networks in Squamous Cell Carcinomas

Abstract: Nuclear factor-κB (NF-κB) transcription factors and the IκB kinases (IKKs) that activate them are central coordinators of innate and adaptive immune responses. More recently, it has become clear that NF-κB signaling also has a critical role in cancer development and progression. The canonical NF-κB pathway contributes to squamous cell carcinoma (SCC) development by interacting with other signaling pathways including tumor suppressive and oncogenic pathways in a tissue specific manner. In this chapter, we will summarize recent advances in the understanding of interconnections between NF-κB and IKKs, including IKKα which has NF-κB independent functions, in the context of SCC development and progression and as potential target for novel chemotherapy approaches.

NF-κB in health and disease

Abstract: Preface.- Understanding the Logic of IkappaB:NF-kappaB Regulation in Structural Terms.- NF-kappaB/Rel proteins and the humoral immune responses of Drosophila melanogaster.- Specialized chromatin patterns in the control of inflammatory gene expression.- IKK regulation and human genetics.- Control of NF-kappaB activity by proteolysis.- NF-kappaB and Innate Immunity.- NF-kappaB and mucosal homeostasis.- IKK and NF-kappaB mediated functions in carcinogenesis.- Macrophages and NF-kappaB in Cancer.- NF-kappaB in liver cancer - the plot thickens.- NF-kappaB as a target for oncogenic viruses.- Inhibition of NF-kappaB signaling as a strategy in disease therapy.- Subject index

Abstract 10070: Sestrin2 Mediates the LKB1-AMPK Signaling Cascade in the Ischemic Heart

Abstract: Background: AMP-activated Protein Kinase (AMPK) has recently emerged as a pertinent stress-activated kinase shown to have substantial cardioprotective capabilities against myocardial ischemia/reper...