Acquired angioedema

Acquired angioedema (AAE) is characterized by acquired deficiency of C1 inhibitor (C1-INH), hyperactivation of the classical pathway of human complement and angioedema symptoms mediated by bradykinin released by inappropriate activation of the contact-kinin system. Angioedema recurs at unpredictable intervals, lasts from two to five days and presents with edema of the skin (face, limbs, genitals), severe abdominal pain with edema of the gastrointestinal mucosa, life-threateing edema of the upper respiratory tract and edema of the oral mucosa and of the tongue. AAE recurs in association with various conditions and particularly with different forms of lymphoproliferative disorders. Neutralizing autoantibodies to C1-INH are present in the majority of patients. The therapeutic approach to a patient with AAE should first be aimed to avoid fatalities due to angioedema and then to avoid the disability caused be angioedema recurrences. Acute attacks can be treated with plasma-derived C1-INH, but some patients become non-responsive and in these patients the kallikrein inhibitor ecallantide and the bradykinin receptor antagonist icatibant can be effective. Angioedema prophylaxis is performed using antifibrinolytic agents and attenuated androgens with antifibrinolytic agents providing somewhat better results. Treatment of the associated disease can resolve AAE in some patients

The small heat shock protein B8 (HSPB8) modulates proliferation and migration of breast cancer cells

open12noBreast cancer (BC) is one of the major causes of cancer death in women and is closely related to hormonal dysregulation. Estrogen receptor (ER)-positive BCs are generally treated with anti hormone therapy using antiestrogens or aromatase inhibitors. However, BC cells may become resistant to endocrine therapy, a process facilitated by autophagy, which may either promote or suppress tumor expansion. The autophagy facilitator HSPB8 has been found overexpressed in some BC. Here we found that HSPB8 is highly expressed and differentially modulated by natural or synthetic selective ER modulators (SERMs), in the triple-positive hormone-sensitive BC (MCF-7) cells, but not in triple-negative MDA-MB-231 BC cells. Specific SERMs induced MCF-7 cells proliferation in a HSPB8 dependent manner whereas, did not modify MDA-MB-231 cell growth. ER expression was unaffected in HSPB8-depleted MCF-7 cells. HSPB8 over-expression did not alter the distribution of MCF-7 cells in the various phases of the cell cycle. Conversely and intriguingly, HSPB8 downregulation resulted in an increased number of cells resting in the G0/G1 phase, thus possibly reducing the ability of the cells to pass through the restriction point. In addition, HSPB8 downregulation reduced the migratory ability of MCF-7 cells. None of these modifications were observed, when another small HSP (HSPB1), also expressed in MCF-7 cells, was downregulated. In conclusion, our data suggest that HSPB8 is involved in the mechanisms that regulate cell cycle and cell migration in MCF-7 cells.openPiccolella, Margherita; Crippa, Valeria; Cristofani, Riccardo; Rusmini, Paola; Galbiati, Mariarita; Elena Cicardi, Maria; Meroni, Marco; Ferri, Nicola; Morelli, Federica F; Carra, Serena; Messi, Elio; Poletti, AngeloPiccolella, Margherita; Crippa, Valeria; Cristofani, Riccardo; Rusmini, Paola; Galbiati, Mariarita; Elena Cicardi, Maria; Meroni, Marco; Ferri, Nicola; Morelli, Federica F; Carra, Serena; Messi, Elio; Poletti, Angel

Prevention of Hereditary Angioedema Attacks with a Subcutaneous C1 Inhibitor

Prevenció; Atac d'angioedema; Inhibidor C1Prevención; Ataque de angioedema; Inhibidor C1Prevention; Angioedema attack; C1 inhibitorBACKGROUND: Hereditary angioedema is a disabling, potentially fatal condition caused by deficiency (type I) or dysfunction (type II) of the C1 inhibitor protein. In a phase 2 trial, the use of CSL830, a nanofiltered C1 inhibitor preparation that is suitable for subcutaneous injection, resulted in functional levels of C1 inhibitor activity that would be expected to provide effective prophylaxis of attacks. METHODS: We conducted an international, prospective, multicenter, randomized, double-blind, placebo-controlled, dose-ranging, phase 3 trial to evaluate the efficacy and safety of self-administered subcutaneous CSL830 in patients with type I or type II hereditary angioedema who had had four or more attacks in a consecutive 2-month period within 3 months before screening. We randomly assigned the patients to one of four treatment sequences in a crossover design, each involving two 16-week treatment periods: either 40 IU or 60 IU of CSL830 per kilogram of body weight twice weekly followed by placebo, or vice versa. The primary efficacy end point was the number of attacks of angioedema. Secondary efficacy end points were the proportion of patients who had a response (≥50% reduction in the number of attacks with CSL830 as compared with placebo) and the number of times that rescue medication was used. RESULTS: Of the 90 patients who underwent randomization, 79 completed the trial. Both doses of CSL830, as compared with placebo, reduced the rate of attacks of hereditary angioedema (mean difference with 40 IU, -2.42 attacks per month; 95% confidence interval [CI], -3.38 to -1.46; and mean difference with 60 IU, -3.51 attacks per month; 95% CI, -4.21 to -2.81; P<0.001 for both comparisons). Response rates were 76% (95% CI, 62 to 87) in the 40-IU group and 90% (95% CI, 77 to 96) in the 60-IU group. The need for rescue medication was reduced from 5.55 uses per month in the placebo group to 1.13 uses per month in the 40-IU group and from 3.89 uses in the placebo group to 0.32 uses per month in the 60-IU group. Adverse events (most commonly mild and transient local site reactions) occurred in similar proportions of patients who received CSL830 and those who received placebo. CONCLUSIONS: In patients with hereditary angioedema, the prophylactic use of a subcutaneous C1 inhibitor twice weekly significantly reduced the frequency of acute attacks. (Funded by CSL Behring; COMPACT EudraCT number, 2013-000916-10 , and ClinicalTrials.gov number, NCT01912456)

Hereditary Angioedema: The Dawn of a New Era of Hereditary Angioedema Management

This symposium provided an overview of past, current, and future therapies and routes of administration for patients with hereditary angioedema (HAE). Prof Cicardi opened the symposium by welcoming attendees and introducing the main topics of the session. Prof Magerl then focussed on treatments that are currently used for acute and prophylactic management of patients with HAE and highlighted that there is an unmet medical need in terms of better prophylactic treatment options. Prof Craig summarised the clinical evidence gathered over the last decades and shared the key findings and insights that led to our current understanding of the disease and laid the foundations for current and future treatment approaches. Prof Zuraw presented the findings from the pivotal Phase III COMPACT trial that explored the efficacy and safety of a self-administered subcutaneous (SC) nanofiltered C1-esterase inhibitor concentrate (C1-INH[SC]) for the prevention of HAE attacks

The protein quality control system in motoneuron diseases

Spinal and bulbar muscular atrophy (SBMA) is a motoneuronal diseases caused by an elogated polyglutamine (polyQ) tract in the androgen receptor (AR). The polyQ expansion causes the AR protein to misfold and the binding with the ligand testosterone triggers a cascade of events, including ARpolyQ aggregation, that led to motoneuron death. The intracellular accumulation of misfolded ARpolyQ both altered the protein quality control system (PQC) and impaired the protective mechanisms deputed to refolding and clearance of misfolded proteins. In PQC, the molecular chaperones allow the refolding or the clearance of the misfolded proteins through the Ubiquitin Proteasome system (UPS) or the autophagic pathway. Moreover, emerging evidence reveal that ARpolyQ toxicity is not related only to motoneuron degeneration but also skeletal muscle damage plays a primary role in SBMA. AIM: The aim of the study was both to unravell the contribution of PQC in SBMA and to find molecular and pharmacological approaches for modulating PQC as potential therapeutic target. Methods: Western blot and filter retardation assay were used to analyse the biochemical properties of ARpolyQ and the protein level of PQC markers. RT-qPCR was used to quantify the mRNA expression of PQC genes in presence of ARpolyQ. Results: In SBMA motoneuronal cell line, we demonstrated that both UPS and autophagic pathway are impaired or blocked, leading to ARpolyQ accumulation into the aggregates. Moreover, analysis in SBMA animal model showed that in the spinal cord and in the skeletal muscle, the PQC could differ considerably in how degrading the mutant and misfolded ARpolyQ. In these conditions of PQC impairment we tested, in SBMA cell model, the overexpression of the small heat shock protein B8 (HspB8), involved in the autophagic pathway. HpB8 led to the autophagic removal of misfolded ARpolyQ, restorating the intracellular autophagic flux. Interestingly, we found that trehalose, a known autophagic stimulator, was able to induce the HspB8 expression and to facilitate the ARpolyQ clearance. Then, we tested the combined treatment of trehalose with Bicalutamide, an antiandrogen. Bicalutamide is able to slow down AR nuclear translocation and to retain it into the cytoplasm, where the autophagic pathway is active. Bicalutamide and trehalose showed synergic activity in the degradation of ARpolyQ. Conclusions: the PQC plays a crucial role in SBMA, the modulation of its activity with trehalose and Bicalutamide might be a promising approach for this no cure disease

Aberrant Autophagic Response in The Muscle of A Knock-in Mouse Model of Spinal and Bulbar Muscular Atrophy

Spinal and bulbar muscular atrophy (SBMA) is characterized by loss of motoneurons and sensory neurons, accompanied by atrophy of muscle cells. SBMA is due to an androgen receptor containing a polyglutamine tract (ARpolyQ) that misfolds and aggregates, thereby perturbing the protein quality control (PQC) system. Using SBMA AR113Q mice we analyzed proteotoxic stress-induced alterations of HSPB8-mediated PQC machinery promoting clearance of misfolded proteins by autophagy. In muscle of symptomatic AR113Q male mice, we found expression upregulation of Pax-7, myogenin, E2-ubiquitin ligase UBE2Q1 and acetylcholine receptor (AchR), but not of MyoD, and of two E3-ligases (MuRF-1 and Cullin3). TGF beta 1 and PGC-1 alpha were also robustly upregulated. We also found a dramatic perturbation of the autophagic response, with upregulation of most autophagic markers (Beclin-1, ATG10, p62/SQSTM1, LC3) and of the HSPB8-mediated PQC response. Both HSPB8 and its co-chaperone BAG3 were robustly upregulated together with other specific HSPB8 interactors (HSPB2 and HSPB3). Notably, the BAG3: BAG1 ratio increased in muscle suggesting preferential misfolded proteins routing to autophagy rather than to proteasome. Thus, mutant ARpolyQ induces a potent autophagic response in muscle cells. Alteration in HSPB8-based PQC machinery may represent muscle-specific biomarkers useful to assess SBMA progression in mice and patients in response to pharmacological treatments

A dysfunctional Cl inhibitor protein with a new reactive center mutation (Arg-444→Leu)

AbstractA Pl mutation (Arg-444→Leu) was identified in a dysfunctional Cl inhibitor from a patient with type 2 hereditary angioneurotic edema. The mutation was defined at the level of the protein (by sequence analysis of the Pseudomonas aeruginosa elastase-derived reactive center peptide), and the mRNA (CGC→CTC) (by sequence analysis of PCR-amplified DNA)

The small heat shock protein B8 (HSPB8) efficiently removes aggregating species of dipeptides produced in C9ORF72-related neurodegenerative diseases

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two neurodegenerative diseases in which similar pathogenic mechanisms are involved. Both diseases associate to the high propensity of specific misfolded proteins, like TDP-43 or FUS, to mislocalize and aggregate. This is partly due to their intrinsic biophysical properties and partly as a consequence of failure of the neuronal protein quality control (PQC) system. Several familial ALS/FTD cases are linked to an expansion of a repeated G4C2 hexanucleotide sequence present in the C9ORF72 gene. The G4C2, which localizes in an untranslated region of the C9ORF72 transcript, drives an unconventional repeat-associated ATG-independent translation. This leads to the synthesis of five different dipeptide repeat proteins (DPRs), which are not âclassicalâ misfolded proteins, but generate aberrant aggregation-prone unfolded conformations poorly removed by the PQC system. The DPRs accumulate into p62/SQSTM1 and ubiquitin positive inclusions. Here, we analyzed the biochemical behavior of the five DPRs in immortalized motoneurons. Our data suggest that while the DPRs are mainly processed via autophagy, this system is unable to fully clear their aggregated forms, and thus they tend to accumulate in basal conditions. Overexpression of the small heat shock protein B8 (HSPB8), which facilitates the autophagy-mediated disposal of a large variety of classical misfolded aggregation-prone proteins, significantly decreased the accumulation of most DPR insoluble species. Thus, the induction of HSPB8 might represent a valid approach to decrease DPR-mediated toxicity and maintain motoneuron viability

A transcriptomic study of Hereditary Angioedema attacks

Background: Hereditary angioedema (HAE) caused by C1-inhibitor deficiency is a lifelong illness characterized by recurrent acute attacks of localized skin or mucosal edema. Activation of the kallikrein/bradykinin pathway at the endothelial cell level has a relevant pathogenetic role in acute HAE attacks. Moreover, other pathways are involved given the variable clinical expression of the disease in different patients. Objective: We sought to explore the involvement of other putative genes in edema formation. Methods: We performed a PBMC microarray gene expression analysis on RNA isolated from patients with HAE during an acute attack and compared them with the transcriptomic profile of the same patients in the remission phase. Results: Gene expression analysis identified 23 genes significantly modulated during acute attacks that are involved primarily in the natural killer cell signaling and leukocyte extravasation signaling pathways. Gene set enrichment analysis showed a significant activation of relevant biological processes, such as response to external stimuli and protein processing (q &lt; 0.05), suggesting involvement of PBMCs during acute HAE attacks. Upregulation of 2 genes, those encoding adrenomedullin and cellular receptor for urokinase plasminogen activator (uPAR), which occurs during an acute attack, was confirmed in PBMCs of 20 additional patients with HAE by using real-time PCR. Finally, in vitro studies demonstrated the involvement of uPAR in the generation of bradykinin and endothelial leakage. Conclusions: Our study demonstrates the increase in levels of adrenomedullin and uPAR in PBMCs during an acute HAE attack. Activation of these genes usually involved in regulation of vascular tone and in inflammatory response might have a pathogenic role by amplifying bradykinin production and edema formation in patients with HAE