Decreased survival in patients treated by chemotherapy after targeted therapy compared to immunotherapy in metastatic melanoma.

BACKGROUND: Cytotoxic chemotherapy (CC) is currently used in metastatic melanoma after patients have developed resistance to immune checkpoint inhibitors (ICI) and/or Mitogen-Activated Protein Kinase inhibitors (MAPKi). We sought to evaluate if a previous treatment by ICI or MAPKi influences clinical outcomes in patients treated by CC in metastatic melanoma. METHODS: Eighty-eight patients with a metastatic melanoma, treated by CC after a previous treatment by ICI or MAPKi between January 2009 and October 2019, were retrospectively analyzed. Progression-Free-Survival (PFS), Overall Survival (OS), Overall Response Rate (ORR), and Disease Control Rate (DCR) were evaluated in patients treated by CC according to their prior treatment by ICI or MAPKi. RESULTS: Patients treated by CC after ICI tended to have a better median PFS (2.81 months (2.39-5.30) versus 2.40 months (0.91-2.75), p = 0.023), median OS (6.03 months (3.54-11.54) versus 4.44 months (1.54-8.59), p = 0.27), DCR (26.0% vs. 10.5%, p = 0.121) and ORR (22.0% vs. 7.9% p = 0.134) than those previously treated by MAPKi. CONCLUSIONS: A prior treatment by an MAPKi may be associated with a worse response to CC than ICI, and further investigations should be performed to confirm if there is a clinical benefit to propose CC in this setting.

Immunomodulatory drugs in multiple myeloma: Impact of the SCARMET (Self CARe and MEdication Toxicity) educational intervention on outpatients' knowledge to manage adverse effects.

Long-term multiple myeloma therapy by immunomodulatory drugs (IMiDs) raises the question of management of adverse effects. The aim of this study is to assess the impact of an educational session for patients on the acquisition of knowledge to manage hematologic and thromboembolic adverse effects of IMiDs. In this prospective single-center study, patients attended an educational session with a hospital clinical pharmacist and a nurse. The primary endpoint was the patient's level of knowledge for the management of IMiDs adverse effects, assess with a dedicated questionnaire administered before the session then 1 and 6 months after. Assessment of knowledge was combined with self-assessment of certainty. The secondary endpoints were adherence and IMiD treatment satisfaction. 50 patients were included. Patient knowledge increased at 1 month (p<0.001) despite a loss of knowledge at 6 months (p<0.05). Six months after the educational intervention, the number of patients with skills considered satisfactory by the pharmacist and nurse increased (p<0.01). Most patients showed satisfactory adherence, with medication possession ratio ≥ 80%. The Self CARe and MEdication Toxicity (SCARMET) study highlighted the impact of multidisciplinary follow-up in multiple myeloma patients to improve knowledge of toxicity self-management.

The E3 ubiquitin ligases HOIP and cIAP1 are recruited to the TNFR2 signaling complex and mediate TNFR2-induced canonical NF-κB signaling.

Tumor Necrosis Factor (TNF) is a proinflammatory cytokine that elicits its action by binding to two cell surface TNF receptors (TNFR), TNFR1 and TNFR2, which are expressed by many different cell types. Stimulation of TNFR1 activates canonical NF-κB signaling, leading to the NF-κB dependent expression of a large number of genes. Canonical NF-κB signaling requires the assembly of a TNFR1 signaling complex at the cell membrane, whose formation is regulated by different protein ubiquitination events. In this context, recruitment of the Linear Ubiquitin Chain Assembly Complex (LUBAC) to TNFR1 plays an important role by mediating M1-linked polyubiquitination of specific NF-κB signaling proteins. In contrast to TNFR1, much less is known about the role of ubiquitination in TNFR2 signaling. Here we demonstrate that specific TNFR2 stimulation rapidly triggers M1- and K63-linked polyubiquitination at the TNFR2 signaling complex. In agreement, TNFR2 stimulation induces the recruitment of HOIP, a LUBAC component and the only known E3 ubiquitin ligase for M1-polyubiquitination, to the TNFR2 signaling complex. Also cIAP1, a E3 ubiquitin ligase able to modify proteins with K63-polyubiquitin chains, was recruited to the TNFR2 signaling complex. Treatment of cells with a cIAP antagonist inhibited the recruitment of HOIP and prevented HOIP-mediated M1-ubiquitination of the TNFR2 signaling complex, indicating that HOIP recruitment to the TNFR2 relies on cIAPs. Finally, we show that both HOIP and cIAP1 are required for TNFR2-induced canonical NF-κB activation. Together, our findings demonstrate an important role for M1- and K63-linked polyubiquitination in TNFR2 signaling.

[Intelligent videosurveillance and falls detection: Perceptions of professionals and managers]. / Vidéosurveillance intelligente et détection des chutes: perception des professionnels et des gestionnaires.

DESCRIPTION: Gerontechnologies can be used to detect accidental falls. However, existing systems do not entirely meet users' expectations. Our team developed an intelligent video-monitoring systems to fill these gaps. Authors advocate consulting potential users at the early stages of the design of gerontechnologies and integrating their suggestions. PURPOSE: This study aims to explore health care workers' opinion regarding the intelligent video monitoring to detect falls by older adults living at home. METHOD: This qualitative study explored the opinions of 31 participants using focus groups. Transcripts were analyzed using predetermined codes based on the competence model. FINDINGS: Participants reported several advantages for using the intelligent video monitoring and provided suggestions for improving its use. IMPLICATIONS: The participants' suggestions and comments will help to improve the system and match it to users' needs.

MALT1 cleaves the E3 ubiquitin ligase HOIL-1 in activated T cells, generating a dominant negative inhibitor of LUBAC-induced NF-κB signaling.

Human paracaspase 1 (PCASP1), better known as mucosa associated lymphoid tissue lymphoma translocation 1 (MALT1), plays a key role in immunity and inflammation by regulating gene expression in lymphocytes and other immune cell types. Deregulated MALT1 activity has been implicated in autoimmunity, immunodeficiency and certain types of lymphoma. As a scaffold MALT1 assembles downstream signaling proteins for nuclear factor-κB (NF-κB) activation, while its proteolytic activity further enhances NF-κB activation by cleaving NF-κB inhibitory proteins. MALT1 also processes and inactivates a number of mRNA destabilizing proteins, which further fine-tunes gene expression. MALT1 protease inhibitors are currently developed for therapeutic targeting. Here we show that T cell activation, as well as overexpression of the oncogenic fusion protein API2-MALT1, induces the MALT1-mediated cleavage of haem-oxidized IRP2 ubiquitin ligase 1 (HOIL-1). In addition, to acting as a K48-polyubiquitin specific E3 ubiquitin ligase for different substrates, HOIL-1 co-operates in a catalytic-independent manner with the E3 ubiquitin ligase HOIL-1L interacting protein (HOIP) as part of the linear ubiquitin chain assembly complex (LUBAC). Intriguingly, cleavage of HOIL-1 does not directly abolish its ability to support HOIP-induced NF-κB signaling, which is still mediated by the N-terminal cleavage fragment, but generates a C-terminal fragment with LUBAC inhibitory properties. We propose that MALT1-mediated HOIL-1 cleavage provides a gain-of-function mechanism that is involved in the negative feedback regulation of NF-κB signaling.

XEDAR activates the non-canonical NF-κB pathway.

Members of the tumor necrosis factor receptor (TNFR) superfamily are involved in a number of physiological and pathological responses by activating a wide variety of intracellular signaling pathways. The X-linked ectodermal dysplasia receptor (XEDAR; also known as EDA2R or TNFRSF27) is a member of the TNFR superfamily that is highly expressed in ectodermal derivatives during embryonic development and binds to ectodysplasin-A2 (EDA-A2), a member of the TNF family that is encoded by the anhidrotic ectodermal dysplasia (EDA) gene. Although XEDAR was first described in the year 2000, its function and molecular mechanism of action is still largely unclear. XEDAR has been reported to activate canonical nuclear factor κB (NF-κB) signaling and mitogen-activated protein (MAP) kinases. Here we report that XEDAR is also able to trigger the non-canonical NF-κB pathway, characterized by the processing of p100 (NF-κB2) into p52, followed by nuclear translocation of p52 and RelB. We provide evidence that XEDAR-induced p100 processing relies on the binding of XEDAR to TRAF3 and TRAF6, and requires the kinase activity of NIK and IKKα. We also show that XEDAR stimulation results in NIK accumulation and that p100 processing is negatively regulated by TRAF3, cIAP1 and A20.

The multifaceted role of the E3 ubiquitin ligase HOIL-1: beyond linear ubiquitination.

Ubiquitination controls and fine-tunes many signaling processes driving immunity, inflammation, and cancer. The E3 ubiquitin ligase HOIL-1 (heme-oxidized IRP2 ubiquitin ligase-1) is increasingly implicated in different signaling pathways and plays a vital role in immune regulation. HOIL-1 co operates with the E3 ubiquitin ligase HOIP (HOIL-1 interacting protein) to modify specific nuclear factor-κB (NF-κB) signaling proteins with linear M1-linked polyubiquitin chains. In addition, through its ability to also add K48-linked polyubiquitin chains to specific substrates, HOIL-1 has been linked with antiviral signaling, iron and xenobiotic metabolism, cell death, and cancer. HOIL-1 deficiency in humans leads to myopathy, amylopectinosis, auto-inflammation, and immunodeficiency associated with an increased frequency of bacterial infections. HOIL-1-deficient mice exhibit amylopectin-like deposits in the myocardium, pathogen-specific immunodeficiency, but minimal signs of hyper-inflammation. This review summarizes current knowledge on the mechanism of action of HOIL-1 and highlights recent advances regarding its role in health and disease.

MALT1--a universal soldier: multiple strategies to ensure NF-κB activation and target gene expression.

The paracaspase MALT1 (mucosa associated lymphoid tissue lymphoma translocation gene 1) is an intracellular signaling protein that plays a key role in innate and adaptive immunity. It is essential for nuclear factor κB (NF-κB) activation and proinflammatory gene expression downstream of several cell surface receptors. MALT1 has been most studied in the context of T-cell receptor-induced NF-κB signaling, supporting T-cell activation and proliferation. In addition, MALT1 hyperactivation is associated with specific subtypes of B-cell lymphoma, where it controls tumor cell proliferation and survival. For a long time, MALT1 was believed to function solely as a scaffold protein, providing a platform for the assembly of other NF-κB signaling proteins. However, this view changed dramatically when MALT1 was found to have proteolytic activity that further fine-tunes signaling. MALT1 proteolytic activity is essential for T-cell activation and lymphomagenesis, suggesting that MALT1 is a promising therapeutic target for the treatment of autoimmune diseases and distinct lymphoma entities. However, interference with MALT1 activity may pose a dangerous threat to the normal functioning of the immune system and should be evaluated with great care. Here we discuss the current knowledge on the scaffold and protease functions of MALT1, including an overview of its substrates and the functional implications of their cleavage.

The biology of A20-binding inhibitors of NF-kappaB activation (ABINs).

The family of A20-Binding Inhibitors of NF-kappaB (ABINs) consists of three proteins, ABIN-1, ABIN-2 and ABIN-3, which were originally identified as A20-binding proteins and inhibitors of cytokines and Lipopolysaccharide (LPS) induced NF-kappaB activation. ABIN family members have limited sequence homology in a number of short regions that mediate A20-binding, ubiquitin-binding, and NF-kappaB inhibition. The functional role of A20 binding to ABINs remains unclear, although an adaptor function has been suggested. ABIN-1 and ABIN-3 expression is upregulated when cells are triggered by NF-kappaB-activating stimuli, suggesting a role for these ABINs in a negative feedback regulation of NF-kappaB signaling. Additional ABIN functions have been reported such as inhibition of TNF-induced hepatocyte apoptosis, regulation of HIV-1 replication for ABIN-1, and Tumor Progression Locus 2 (TPL-2)-mediated Extracellular signal-Regulated Kinase (ERK) activation for ABIN-2. In mice, ABIN-1 overexpression reduces allergic airway inflammation and TNF-mediated liver injury, ABIN-2 overexpression delays liver regeneration, and ABIN-3 overexpression partially protects against LPS-induced acute liver failure. Analysis of mice deficient in ABIN-1 or ABIN-2 demonstrates the important immune regulatory function of ABINs. Future studies should clarify the functional implication of the A20-ABIN interaction in supporting ABINs' mechanisms of action.

The use of transdermal buprenorphine to relieve radiotherapy-related pain in head and neck cancer patients.

Many head and neck cancer (HNC) patients experience painful therapy-related mucositis and dermatitis. This prospective observational study evaluated transdermal buprenorphine use in HNC patients to relieve treatment-related pain. During treatment with paracetamol or tramadol, visual analogue scale (VAS)-pain scores >30/100 occurred in 26/45 patients 4 weeks after starting cancer therapy, persisting for ≥2 weeks after treatment. These patients subsequently received transdermal buprenorphine. Pain therapy should be more accurately up-titrated to the maximum recommended dose (140 µg/hr) where necessary to maintain pain scores ≤30/100 and, for some patients, should be continued for 6 weeks after the last cancer treatment day.

IκB kinase ε (IKKε): a therapeutic target in inflammation and cancer.

The innate immune system forms our first line of defense against invading pathogens and relies for a major part on the activation of two transcription factors, NF-κB and IRF3. Signaling pathways that activate these transcription factors are intertwined at the level of the canonical IκB kinases (IKKα, IKKß) and non-canonical IKK-related kinases (IKKε, TBK1). Recently, significant progress has been made in understanding the function and mechanism of action of IKKε in immune signaling. In addition, IKKε impacts on cell proliferation and transformation, and is thereby also classified as an oncogene. Studies with IKKε knockout mice have illustrated a key role for IKKε in inflammatory and metabolic diseases. In this review we will highlight the mechanisms by which IKKε impacts on signaling pathways involved in disease development and discuss its potential as a novel therapeutic target.

A20 inhibits LUBAC-mediated NF-κB activation by binding linear polyubiquitin chains via its zinc finger 7.

Linear polyubiquitination of proteins has recently been implicated in NF-κB signalling and is mediated by the linear ubiquitin chain assembly complex (LUBAC), consisting of HOIL-1, HOIP and Sharpin. However, the mechanisms that regulate linear ubiquitination are still unknown. Here, we show that A20 is rapidly recruited to NEMO and LUBAC upon TNF stimulation and that A20 inhibits LUBAC-induced NF-κB activation via its C-terminal zinc-finger 7 (ZF7) domain. Expression of a polypeptide corresponding to only ZF7 was sufficient to inhibit TNF-induced NF-κB activation. Both A20 and ZF7 can form a complex with NEMO and LUBAC, and are able to prevent the TNF-induced binding of NEMO to LUBAC. Finally, we show that ZF7 preferentially binds linear polyubiquitin chains in vitro, indicating A20-ZF7 as a novel linear ubiquitin-binding domain (LUBID). We thus propose a model in which A20 inhibits TNF- and LUBAC-induced NF-κB signalling by binding to linear polyubiquitin chains via its seventh zinc finger, which prevents the TNF-induced interaction between LUBAC and NEMO.

A20 (Tnfaip3) deficiency in myeloid cells protects against influenza A virus infection.

The innate immune response provides the first line of defense against viruses and other pathogens by responding to specific microbial molecules. Influenza A virus (IAV) produces double-stranded RNA as an intermediate during the replication life cycle, which activates the intracellular pathogen recognition receptor RIG-I and induces the production of proinflammatory cytokines and antiviral interferon. Understanding the mechanisms that regulate innate immune responses to IAV and other viruses is of key importance to develop novel therapeutic strategies. Here we used myeloid cell specific A20 knockout mice to examine the role of the ubiquitin-editing protein A20 in the response of myeloid cells to IAV infection. A20 deficient macrophages were hyperresponsive to double stranded RNA and IAV infection, as illustrated by enhanced NF-κB and IRF3 activation, concomitant with increased production of proinflammatory cytokines, chemokines and type I interferon. In vivo this was associated with an increased number of alveolar macrophages and neutrophils in the lungs of IAV infected mice. Surprisingly, myeloid cell specific A20 knockout mice are protected against lethal IAV infection. These results challenge the general belief that an excessive host proinflammatory response is associated with IAV-induced lethality, and suggest that under certain conditions inhibition of A20 might be of interest in the management of IAV infections.

Structure and function of the Type III secretion system of Pseudomonas aeruginosa.

Pseudomonas aeruginosa is a dangerous pathogen particularly because it harbors multiple virulence factors. It causes several types of infection, including dermatitis, endocarditis, and infections of the urinary tract, eye, ear, bone, joints and, of particular interest, the respiratory tract. Patients with cystic fibrosis, who are extremely susceptible to Pseudomonas infections, have a bad prognosis and high mortality. An important virulence factor of P. aeruginosa, shared with many other gram-negative bacteria, is the type III secretion system, a hollow molecular needle that transfers effector toxins directly from the bacterium into the host cell cytosol. This complex macromolecular machine works in a highly regulated manner and can manipulate the host cell in many different ways. Here we review the current knowledge of the structure of the P. aeruginosa T3SS, as well as its function and recognition by the immune system. Furthermore, we describe recent progress in the development and use of therapeutic agents targeting the T3SS.

Regulation of TNF-induced NF-κB activation by different cytoplasmic ubiquitination events.

TNF is a multifunctional cytokine that plays a key role in innate immunity by inducing the expression of a variety of genes that are involved in an inflammatory response. TNF-induced NF-κB activation is one of the best studied signaling pathways in mammalian cells and has recently led to a revival of research in the biology of ubiquitin. Many NF-κB signaling proteins are modified by specific ubiquitin ligases with different types of ubiquitin chains that are recognized by other proteins and which determine the outcome of ubiquitination. In addition, specific de-ubiquitinases make the whole process reversible. This review summarizes recent findings that have shaped our current understanding on the role of cytoplasmic ubiquitination events in the regulation of TNF-induced NF-κB signaling.

Linear ubiquitination in NF-κB signaling and inflammation: What we do understand and what we do not.

Despite its small size, ubiquitin is one of the most versatile signaling molecules in the cell and affects distinct cellular processes. It forms the building block of a repertoire of posttranslational modifications of cellular proteins, ranging from the attachment of a single ubiquitin to ubiquitin chains of different linkage. Proteins that contain ubiquitin chain-specific ubiquitin-binding domains recognize different types of ubiquitination and determine the mode of signaling of modified proteins. Polyubiquitin chains were thought to be formed only by the conjugation of the ubiquitin C-terminal Gly to one of the seven internal Lys residues of another ubiquitin. However, the C-terminal Gly was recently shown to also link to the N-terminus of another ubiquitin to form head-to-tail polyubiquitin chains, which is referred to as linear ubiquitination. These linear linkages can be assembled and conjugated to another protein by an E3 ligase complex known as LUBAC, and are recognized by a particular ubiquitin-binding domain known as UBAN. Both have been implicated in the regulation of TNF-induced NF-κB signaling, which induces the expression of a wide range of proteins that mediate many biological processes including inflammation and cell survival. We discuss the molecular players and mechanisms that determine the specificity and outcome of linear ubiquitination in NF-κB signaling, as well as future directions and challenges ahead.

TAX1BP1, a ubiquitin-binding adaptor protein in innate immunity and beyond.

The innate immune system senses and protects against invading microorganisms and endogenous danger signals by triggering inflammatory and antimicrobial responses. However, dysregulation of these pathways, which involve the transcription factors nuclear factor-κB (NF-κB) and interferon regulatory factor (IRF) 3, can lead to severe inflammatory diseases. Tax1-binding protein 1 (TAX1BP1) plays a key role in the negative regulation of NF-κB and IRF3 signaling by acting in concert with the ubiquitin-editing enzyme A20. In addition to regulating A20 function in anti-inflammatory and antiviral signaling pathways, TAX1BP1 also coordinates its antiapoptotic activities. Moreover, TAX1BP1 can also function as a transcriptional coactivator for nuclear receptors and viral transactivators. In this review, we discuss these findings in light of the emerging role of TAX1BP1 as a ubiquitin-binding adaptor protein.

Expression, biological activities and mechanisms of action of A20 (TNFAIP3).

A20 (also known as TNFAIP3) is a cytoplasmic protein that plays a key role in the negative regulation of inflammation and immunity. Polymorphisms in the A20 gene locus have been identified as risk alleles for multiple human autoimmune diseases, and A20 has also been proposed to function as a tumor suppressor in several human B-cell lymphomas. A20 expression is strongly induced by multiple stimuli, including the proinflammatory cytokines TNF and IL-1, and microbial products that trigger pathogen recognition receptors, such as Toll-like receptors. A20 functions in a negative feedback loop, which mediates its inhibitory functions by downregulating key proinflammatory signaling pathways, including those controlling NF-κB- and IRF3-dependent gene expression. Activation of these transcription factors is controlled by both K48- and K63- polyubiquitination of upstream signaling proteins, respectively triggering proteasome-mediated degradation or interaction with other signaling proteins. A20 turns off NF-κB and IRF3 activation by modulating both types of ubiquitination. Induction of K48-polyubiquitination by A20 involves its C-terminal zinc-finger ubiquitin-binding domain, which may promote interaction with E3 ligases, such as Itch and RNF11 that are involved in mediating A20 inhibitory functions. A20 is thought to promote de-ubiquitination of K63-polyubiquitin chains either directly, due to its N-terminal deubiquitinase domain, or by disrupting the interaction between E3 and E2 enzymes that catalyze K63-polyubiquitination. A20 is subject to different mechanisms of regulation, including phosphorylation, proteolytic processing, and association with ubiquitin binding proteins. Here we review the expression and biological activities of A20, as well as the underlying molecular mechanisms.

ABINs: A20 binding inhibitors of NF-kappa B and apoptosis signaling.

ABINs have been described as three different proteins (ABIN-1, ABIN-2, ABIN-3) that bind the ubiquitin-editing nuclear factor-kappaB (NF-kappaB) inhibitor protein A20 and which show limited sequence homology. Overexpression of ABINs inhibits NF-kappaB activation by tumor necrosis factor (TNF) and several other stimuli. Similar to A20, ABIN-1 and ABIN-3 expression is NF-kappaB dependent, implicating a potential role for the A20/ABIN complex in the negative feedback regulation of NF-kappaB activation. Adenoviral gene transfer of ABIN-1 has been shown to reduce NF-kappaB activation in mouse liver and lungs. However, ABIN-1 as well as ABIN-2 deficient mice exhibit only slightly increased or normal NF-kappaB activation, respectively, possibly reflecting redundant NF-kappaB inhibitory activities of multiple ABINs. Other functions of ABINs might be non-redundant. For example, ABIN-1 shares with A20 the ability to inhibit TNF-induced apoptosis and as a result ABIN-1 deficient mice die during embryogenesis due to TNF-dependent fetal liver apoptosis. On the other hand, ABIN-2 is required for optimal TPL-2 dependent extracellularly regulated kinase activation in macrophages treated with TNF or Toll-like receptor ligands. ABINs have recently been shown to contain an ubiquitin-binding domain that is essential for their NF-kappaB inhibitory and anti-apoptotic activities. In this context, ABINs were proposed to function as adaptors between ubiquitinated proteins and other regulatory proteins. Alternatively, ABINs might disrupt signaling complexes by competing with other ubiquitin-binding proteins for the binding to specific ubiquitinated targets. Altogether, these findings implicate an important role for ABINs in the regulation of immunity and tissue homeostasis.

Cellular expression of A20 and ABIN-3 in response to Toll-like receptor-4 stimulation.

Although Toll-like receptor (TLR)-induced expression of several proinflammatory genes is required to provoke an efficient immune response, excessive or prolonged activation of TLR signaling can contribute to the development of septic shock and several inflammatory diseases. Given this inherent danger of unrestrained TLR signaling to the organism, it is not surprising that many negative feedback mechanisms have evolved to hold TLR signaling in check. In this context, TLR stimulation induces several negative regulators of TLR-induced signaling to nuclear factor (NF)-kappaB dependent gene expression. Here we describe the use of Western blotting and reverse transcriptase polymerase chain reaction (RT-PCR) to study respectively the cellular protein and mRNA expression levels of the NF-kappaB inhibitory proteins A20 and ABIN-3 in response to TLR4 stimulation by lipopolysaccharide (LPS).