Search

Deubiquitinating enzymes are key regulators of the ubiquitin-proteasome system and cell cycle, and their dysfunction leads to tumorigenesis. Our in vivo drop-out screens in patient-derived xenograft models identify USP7 as a regulator of melanoma. We show that USP7 downregulation induces cellular senescence, arresting melanoma growth in vivo and proliferation in vitro in BRAF- and NRAS-mutant melanoma. We provide a comprehensive understanding of targets and networks affected by USP7 depletion by performing a global transcriptomic and proteomics analysis. We show that RRM2 is a USP7 target and is regulated by USP7 during S phase of the cell cycle. Ectopic expression of RRM2 in USP7-depleted cells rescues the senescent phenotype. Pharmacological inhibition of USP7 by P5091 phenocopies the shUSP7-induced senescent phenotype. We show that the bifunctional histone deacetylase (HDAC)/LSD1 inhibitor domatinostat has an additive antitumor effect, eliminating P5091-induced senescent cells, paving the way to a therapeutic combination for individuals with melanoma.

Beer contains a large variety of different molecules, of which some can chelate Ca 2+. Here, we show that in PE/CA-PJ15 cells, an experimental model previously employed to investigate Ca 2+ homeostasis, chemical entities with Ca 2+ -chelating properties can markedly impact intra- and extra-cellular levels of the metal ion. This was consistently shown by commercial beers, as well as aliquots of unfinished product taken during the last step (clarification) of the brewing process. Our data suggest that a large number of molecules with chelating properties, can cross the cell membrane and, thus, potentially lead to important biological effects associated with changes in Ca 2+ homeostasis. In this regard, when PE/CA-PJ15 cells were exposed to H 2 O 2 in order to experimentally prompt an oxidative stress, beer antagonized a non-capacitative Ca 2+ entry that was otherwise elicited by H 2 O 2 in its absence. Higher Ca 2+ -chelating activity of stout, as compared to lager beer, suggest that melanoidins, which are generally present in dark malts, are major chelating agents in dark beers. Further, based on dose-response determinations, we report, for the first time, that Ferulic Acid can bind both intra- and extra-cellular Ca 2+ and, as one of the most abundant hydroxycinnamic acids in malted barley, largely account for Ca 2+ chelation. These results support the notion that beer may be considered a natural source of chemical entities that, based on their binding activity to Ca 2+ and, possibly, other metal ions, might be considered as nutritional supplements, detoxification agents, or antibiotics.

In a number of compatible plant‐bacterium interactions, a rise in apoplastic Ca2+ levels is observed, suggesting that Ca2+ represents an important environmental clue, as reported for bacteria infecting mammalians. We demonstrate that Ca2+ entry in Pseudomonas savastanoi pv. savastanoi (Psav ) strain DAPP‐PG 722 is mediated by a Na+/Ca2+ exchanger critical for virulence. Using the fluorescent Ca2+ probe Fura 2‐AM, we demonstrate that Ca2+ enters Psav cells foremost when they experience low levels of energy, a situation mimicking the apoplastic fluid. In fact, Ca2+ entry was suppressed in the presence of high concentrations of glucose, fructose, sucrose or adenosine triphosphate (ATP). Since Ca2+ entry was inhibited by nifedipine and LiCl, we conclude that the channel for Ca2+ entry is a Na+/Ca2+ exchanger. In silico analysis of the Psav DAPP‐PG 722 genome revealed the presence of a single gene coding for a Na+/Ca2+ exchanger (cneA ), which is a widely conserved and ancestral gene within the P. syringae complex based on gene phylogeny. Mutation of cneA compromised not only Ca2+ entry, but also compromised the Hypersensitive response (HR) in tobacco leaves and blocked the ability to induce knots in olive stems. The expression of both pathogenicity (hrpL , hrpA and iaaM ) and virulence (ptz ) genes was reduced in this Psav ‐cneA mutant. Complementation of the Psav ‐cneA mutation restored both Ca2+ entry and pathogenicity in olive plants, but failed to restore the HR in tobacco leaves. In conclusion, Ca2+ entry acts as a ‘host signal’ that allows and promotes Psav pathogenicity on olive plants.

Metastases are the primary cause of cancer-related deaths. The underlying molecular and biological mechanisms remain, however, elusive, thus preventing the design of specific therapies. In melanomas, the metastatic process is influenced by the acquisition of metastasis-associated mutational and epigenetic traits and the activation of metastatic-specific signaling pathways in the primary melanoma. In the current study, we investigated the role of an adaptor protein of the Shc family (ShcD) in the acquisition of metastatic properties by melanoma cells, exploiting our cohort of patient-derived xenografts (PDXs). We provide evidence that the depletion of ShcD expression increases a spread cell shape and the capability of melanoma cells to attach to the extracellular matrix while its overexpression switches their morphology from elongated to rounded on 3D matrices, enhances cells&rsquo, invasive phenotype, as observed on collagen gel, and favors metastasis formation in vivo. ShcD overexpression sustains amoeboid movement in melanoma cells, by suppressing the Rac1 signaling pathway through the confinement of DOCK4 in the cytoplasm. Inactivation of the ShcD signaling pathway makes melanoma cells more sensitive to therapeutic treatments. Consistently, ShcD expression predicts poor outcome in a cohort of 183 primary melanoma patients.

Treatment of metastatic melanoma has been recently revolutionized by the use of targeted and immune inhibitors, though efficiently working only in a fraction of patients. Adverse effects still represent major challenges, as well as the rapid development of drug resistance upon treatment, thus suggesting that it is of utmost importance to elucidate additional molecular pathways and targets to better understand the biology of this tumor. In vivo RNAi screens done in patient-derived xenografts (PDXs) that fully phenocopy the original tumor of the patient represent a powerful tool to identify new putative essential and druggable candidates, and to repurpose drugs already approved for other indications. To this end we have recently generated a platform of melanoma PDXs with which we can recapitulate both melanoma growth and metastasization. We have performed in vivo shRNA screens, where we have found numerous and patient-specific epigenetic genes essential for tumor growth in vivo. With this platform, we have isolated novel frailties whose depletion favors cell senescence. Preliminary data using shRNA libraries of actionable genes for which drugs are already available suggest that specific drugs can be repurposed for melanoma treatment. We have proved that this approach can work in vivo, and we propose to convert it in an in vitro assay to rapidly translate new discoveries to the patient. Note: This abstract was not presented at the conference. Citation Format: Federica Marocchi, Letizia Granieri, Fiorenza Lotti, Fernando Palluzzi, Jole Costanza, Laura Riva, Daniela Bossi, Luisa Lanfrancone. New treatment opportunities by in vivo and in vitro screening approaches in melanoma [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr A15.

Bisphosphonates are the most important class of antiresorptive agents used against osteoclast-mediated bone loss, and, more recently, in oncology. These compounds have high affinity for calcium ions (Ca(2+)) and therefore target bone mineral, where they appear to be internalized selectively by bone-resorbing osteoclasts and inhibit osteoclast function. They are extensively used in healthcare, however they are affected by severe side effects; pharmacological properties of bisphosphonates depend on their molecular structure, which is frequently the cause of poor intestinal adsorption and low distribution. In this work we synthesized six novel bisphosphonate compounds having a variably substituted indole moiety to evaluate their extra- and intracellular calcium chelating ability in PE/CA-PJ15 cells. Preliminary in silico and in vitro ADME studies were also performed and the results suggested that the indole moiety plays an important role in cell permeability and metabolism properties.

Summary: CDK4/6 inhibitors are effective against cancer cells expressing the tumor suppressor RB1, but not RB1-deficient cells, posing the challenge of how to target RB1 loss. In triple-negative breast cancer (TNBC), RB1 and PTEN are frequently inactivated together with TP53. We performed kinome/phosphatase inhibitor screens on primary mouse Rb/p53-, Pten/p53-, and human RB1/PTEN/TP53-deficient TNBC cell lines and identified CDC25 phosphatase as a common target. Pharmacological or genetic inhibition of CDC25 suppressed growth of RB1-deficient TNBC cells that are resistant to combined CDK4/6 plus CDK2 inhibition. Minimal cooperation was observed in vitro between CDC25 antagonists and CDK1, CDK2, or CDK4/6 inhibitors, but strong synergy with WEE1 inhibition was apparent. In accordance with increased PI3K signaling following long-term CDC25 inhibition, CDC25 and PI3K inhibitors effectively synergized to suppress TNBC growth both in vitro and in xenotransplantation models. These results provide a rationale for the development of CDC25-based therapies for diverse RB1/PTEN/TP53-deficient and -proficient TNBCs. : Liu et al. report that inhibition of the protein phosphatase CDC25 kills diverse triple-negative breast cancer (TNBC) cells. Moreover, CDC25 antagonists cooperate with other drugs, such as PI3K inhibitors, to efficiently suppress growth of human TNBC engrafted into mice. Keywords: triple negative breast cancer, basal-like breast cancer, therapy, RB1, PTEN, TP53, CDC25, WEE1, CHK1, checkpoint control

Altres ajuts: This study was funded by the Eugene Devic European Network (EDEN) project (ERA-Net ERARE 2: http://www.erare.eu/financed-projects/eden). Euroimmun AG provided assay kits for groups from Denmark and Hungary at 50% discount, and at no cost to both Italian groups. The work in Oxford was supported by the National Health Service National Specialised Commissioning Group for Neuromyelitis Optica and the National Institute for Health Research Oxford Biomedical Research Centre. Competing interests: AS is funded by Fundació la Marató de TV3 (101610). FT is enrolled in the doctoral programme SPIN funded by the Austrian Science Fund (FWF; project W1206). ZI is funded by Lundbeckfonden and Scleroseforeningen of Denmark. AB has received a grant from Bayer Healthcare on NMO. LZ would like to thank RH for her excellent technical assistance with the assay. RH was supported by a Schrödinger fellowship funded by the Austrian Science Fund (FWF; project J3230). CC acknowledges funding from Fundació la Marató de TV3 (493/C/2012). FP acknowledges funding from the Bundesministerium für Bildung und Forschung (Competence Network Multiple Sclerosis KKNMS). BW acknowledges funding from the Dietmar-Hopp-Stiftung and from Merck Serono. RM and AR acknowledge Nathalie Dufay from NeuroBioTec-Banques (Hospices Civils de Lyon, France) and funding from Association pour la Recherche sur la Sclerose en Plaques (ARSEP). PW has received speaker honoraria from Biogen Idec and Euroimmun AG; holds a patent with Oxford University for LGI1/CASPR2 antibodies, licensed to Euroimmun AG; and for GABAAR antibodies. MR reports other from University Hospital of Innsbruck (TILAK), during the conduct of the study; personal fees from Euroimmun, outside the submitted work. AS has received compensation for consulting services and speaking from Bayer-Schering, Merck-Serono, Biogen-Idec, Sanofi-Aventis, Teva Pharmaceutical Industries Ltd and Novartis. HHN has received travel funding and speaker honoraria from Novartis Healthcare, Biogen Idec, Genzyme Denmark and Teva Denmark. ZI reports grants from Lundbeckfonden, Denmark; Scleroseforeningen, Denmark, during the conduct of the study; personal fees from compensation for consulting services and speaking from Bayer-Schering, Biogen-Idec, Merck-Serono, Novartis, Sanofi-Aventis, and Teva Pharmaceutical Industries Ltd, outside the submitted work. TB reports non-financial support from Euroimmun AG, during the conduct of the study. KR is shareholder and an employee of Euroimmun AG. AB reports grants from Bayer Heathcare, personal fees from Biogen Idec, personal fees from Merck Serono, personal fees from Teva, personal fees from Novartis, personal fees from Genzyme, other from Biogen Idec, other from Novartis, other from Genzyme, other from Roche, other from Alexion Pharmaceuticals, outside the submitted work. LG received congress and travel compensations from Euroimmun. AB received honoraria for serving in the scientific advisory boards of Almirall, Bayer, Biogen Idec, Genzyme, and received speaker honoraria from Biogen Idec, Genzyme, Novartis, TEVA with approval by the Director of AOU San Luigi University Hospital; his institution has received grant support from Bayer, BiogenIdec, Merck, Novartis, TEVA from the Italian Multiple Sclerosis Society, Associazione Ricerca Biomedica ONLUS and San Luigi ONLUS. LZ reports personal fees from Teva Pharmaceutical, personal fees from Novartis, outside the submitted work. MC has received compensation for consulting services and speaking honoraria from Bayer Schering Pharma, Merk Serono, Biogen-Idec, Teva Pharmaceuticals, Sanofi-Aventis, Genzyme, and Novartis. XM has received speaking honoraria and travel expenses for scientific meetings, has been a steering committee member of clinical trials or participated in advisory boards of clinical trials in the past years with Bayer Schering Pharma, Biogen Idec, EMD Merck Serono, Genentech, Genzyme, Novartis, Sanofi-Aventis, Teva Phramaceuticals, Almirall and Roche. MT has received compensation for consulting services and speaking from Bayer-Schering, Merk-Serono, Biogen-Idec, Teva, Sanofi-Aventis, and Novartis. AS reports receiving grants from the Scientific and Technological Research Council of Turkey-Health Sciences Research (grants numbers 109S070 and 112S052); and also unrestricted grants from Bayer-Schering AG and Merck-Serono to their Neurology Department Clinical Neuroimmunology Unit. AS also reports receiving honoraria or consultation fees Biogen Idec, Novartis and Teva. He had received travel and registration coverage for attending several national or international congresses or symposia, from Merck Serono, Biogen Idec, Novartis, Teva, Bayer-Schering and Allergan. AA received grants to her department from The Scientific and Technological Research Institute of Turkey-Health Sciences (grants numbers 109S070 and 112S052), and she also received honoraria, research and travel grants from Teva, Merck-Serono, Gen Ilac, Bayer-Schering, Novartis. FP has received travel funding, speaker honoraria and personal compensation for activities on advisory boards and steering committees from Bayer, Biogen Idec, Alexion, Chugai, MedImmune, MerckSerono, Novartis, Teva, and Sanofi Genzyme. He has received grants from the Guthy Jackson Charitable Foundation and the National Multiple Sclerosis Society of the USA. OA reports grants from German Ministry for Education and Research (BMBF), during the conduct of the study; German Research Foundation (DFG); Hertie Foundation; Biogen; Novartis; Bayer; outside the submitted work; and Honoraria for consultancy and speaking by Biogen, Novartis, Bayer Schering, Teva, Chugai, Genzyme, MedImmune, and Merck Serono. BW reports personal fees from Bayer Healthcare, grants and personal fees from Biogen, Merck Serono; Genzyme, a Sanofi Company; Novartis Pharmaceuticals; TEVA Pharma; grants from Biotest, German Ministry of Education and Research; Dietmar Hopp Foundation; outside the submitted work. H-PH reports personal fees from MedImmune, outside the submitted work. MP is an employee of and holds stock in Euroimmun AG. PT reports non-financial support from Roche Pharmaceuticals, outside the submitted work. SS is an employee of Euroimmun AG. AV is on the Advisory Board for Neurology; was an associate editor for Brain; holds patents with Oxford University for MuSK, LGI1/CASPR2, and GABAAR antibodies, and receives a proportion of royalties. RM reports personal fees from MedImmune, personal fees and non-financial support from Biogen, non-financial support from Merck-Serono, non-financial support from Teva, non-financial support from Novartis, non-financial support from Sanofi, outside the submitted work. Antibodies to cell surface central nervous system proteins help to diagnose conditions which often respond to immunotherapies. The assessment of antibody assays needs to reflect their clinical utility. We report the results of a multicentre study of aquaporin (AQP) 4 antibody (AQP4-Ab) assays in neuromyelitis optica spectrum disorders (NMOSD). Coded samples from patients with neuromyelitis optica (NMO) or NMOSD (101) and controls (92) were tested at 15 European diagnostic centres using 21 assays including live (n=3) or fixed cell-based assays (n=10), flow cytometry (n=4), immunohistochemistry (n=3) and ELISA (n=1). Results of tests on 92 controls identified 12assays as highly specific (0-1 false-positive results). 32 samples from 50 (64%) NMO sera and 34 from 51 (67%) NMOSD sera were positive on at least two of the 12 highly specific assays, leaving 35 patients with seronegative NMO/spectrum disorder (SD). On the basis of a combination of clinical phenotype and the highly specific assays, 66 AQP4-Ab seropositive samples were used to establish the sensitivities (51.5-100%) of all 21 assays. The specificities (85.8-100%) were based on 92 control samples and 35 seronegative NMO/SD patient samples. The cell-based assays were most sensitive and specific overall, but immunohistochemistry or flow cytometry could be equally accurate in specialist centres. Since patients with AQP4-Ab negative NMO/SD require different management, the use of both appropriate control samples and defined seronegative NMOSD samples is essential to evaluate these assays in a clinically meaningful way. The process described here can be applied to the evaluation of other antibody assays in the newly evolving field of autoimmune neurology.

We employed a high-throughput drug library screening platform to identify novel agents affecting thyroid cancer cells. We used human thyroid cancer cell lines to screen a collection of approximately 5200 small molecules with biological and/or pharmacologial properties. Parallel primary screens yielded a number of hits differentially active between thyroid and melanoma cells. Amongst compounds specifically targeting thyroid cancer cells, colchicine emerged as an effective candidate. Colchicine inhibited cell growth which correlated with G2 cell cycle arrest and apoptosis. These effects were hampered through inhibition of MEK1/2 and JNK. In contrast, inhibition of p38-MAPK had little effect, and AKT had no impact on colchicine action. Systemic colchicine inhibited thyroid cancer progression in xenografted mice. These findings demonstrate that our screening platform is an effective vehicle for drug reposition and show that colchicine warrants further attention in well-defined clinical niches such as thyroid cancer.

A salivary proline-rich peptide of 1932 Da showed a dose-dependent antagonistic effect on the cytosolic Ca2+ mobilization induced by progesterone in a tongue squamous carcinoma cell line. Structure-activity studies showed that the activity of the peptide resides in the C-terminal region characterized by a proline stretch flanked by basic residues. Furthermore, lack of activity of the retro-inverso peptide analogue suggested the involvement of stereospecific recognition. Mass spectrometry-based shotgun analysis, combined with Western blotting tests and biochemical data obtained with the Progesterone Receptor Membrane Component 1 (PGRMC1) inhibitor AG205, showed strong evidence that p1932 performs its modulatory action through an interaction with the progesterone receptor PGRMC1, which is predominantly expressed in this cell line and, clearly, plays a role in progesterone induced Ca2+ response. Thus, our results point to p1932 as a modulator of the transduction signal pathway mediated by this protein and, given a well-established involvement of PGRMC1 in tumorigenesis, highlight a possible therapeutic potential of p1932 for the treatment of oral cancer.

The dual phosphatase CDC25 has recently been identified as a target for diverse triple-negative breast cancers including RB1/PTEN/P53-deficient tumors. Moreover, CDC25 inhibitors effectively synergize with PI3K inhibitors to suppress tumor growth. We discuss these findings and the challenges that lie ahead in bringing CDC25 inhibitors to the clinic.

Many multiple sclerosis (MS) patients treated with interferon-beta (IFNbeta) develop anti-IFNbeta antibodies (BAbs), which can interfere with both in vitro and in vivo bioactivity of the injected cytokine. Objective of this study was to correlate these measures. Among the 256 enrolled patients, 11 (4.3%) showed a significant inhibition of the IFNbeta activity in vitro, but no measurable BAbs. As a whole, in vivo bioactivity was inhibited in 9/11 (82%) of these patients. A minority of IFNbeta treated patients have a non-antibody mediated neutralising activity, which competitively inhibits the bioactivity both in vitro and in vivo.

Multiple Sclerosis (MS) is a heterogeneous disease and a variable percentage of patients are non-responders to common treatment. Early diagnosis of non-responders allows change to a more useful therapy for the patient and better allocates a large amount of financial resources. Quantification of Neutralizing antibodies (Nabs) and of biological activity of IFN-β are recognized approaches to identify immuno-pharmacological non-responders. A consistent number of studies have demonstrated that quantification of Myxovirus-induced protein A (MxA) is a valid biomarker to detect immune-pharmacological non responders after one year of treatment. Persistent high titre of Nabs and absence of biological activity predict abolition of IFN-β effects in disease activity measured through MRI, number of relapses and disability. Guidelines and flow-charts including both Nabs and MxA quantification are presented.

identified follicle-like structures containing B cells close to vessels and PDGFRb+ cells forming a reticular network expanding to the parenchyma. To find out if these structures could provide sufficient homing locations which support plasma cells to become long-lived, we performed 5-ethynyl-2′-deoxyuridine (EdU)-pulse experiments. During pulse, EdU is incorporated by dividing cells like plasma blasts. The detection of EdU-positive cells up to seven weeks after pulse suggests that niches in the CNS can favor survival of plasma cells. We then further analyzed the migration of plasma blasts to the CNS. Since the sphingosine-1-phosphate analogon FTY720 (fingolimod) is known to suppress immune cell trafficking, we performed EAE experiments under accompanying treatment with the drug. FTY720treated animals were resistant to EAE in contrast to control animals. Immunofluorescent histological findings confirmed that no immune cell infiltration took place in FTY720-treated animals and the protective effect of FTY720 was not due to retention of immune cells in spleen, lymph nodes or bone marrow, as proved by quantitative FACS analysis. Control mice displayed massive immune cell infiltration in the perivascular space and parenchyma of the CNS, some evidently of long-lived phenotype. These results can be useful to evaluate the therapeutic potential of targeting plasma cells in chronic neuroinflammation.

Objective:We undertook an observational retrospective study to investigate the usefulness of aquaporin-4 (AQP4) antibodies (Ab) titration in the management of patients with neuromyelitis optica (NMO) treated with rituximab (RTX) by studying (1) the correlation between AQP4-Ab titer and disease activity, (2) the influence of RTX on antibody levels, and (3) the association between AQP4-Ab levels and responsiveness to RTX.Methods:A cell-based assay was used for AQP4-Ab titration in 322 serum samples from 7 patients with NMO treated with RTX (median follow-up 65 months), according to a treatment-to-target approach. Serum samples were collected every month following standardized procedures.Results:(1) In group analysis, AQP4-Ab titers correlated with the disease activity, showing higher titers during and preceding relapses than during remission. However, in individual analysis, an increase in AQP4-Ab titers and CD19+ B cells did not always precede a relapse. (2) A reduction of AQP4-Ab titers in the short-term and long-term period was observed during RTX treatment. (3) Reduction of AQP4-Ab titers was observed in responder patients both 3 months after RTX infusion and in the long-term follow-up. In one nonresponder patient, AQP4-Ab levels never decreased during the treatment period.Conclusions:Titration of AQP4-Abs could be useful in the clinical management of patients with NMO treated with RTX: titration before each reinfusion and 3 months after each reinfusion may provide information about responsiveness to RTX. Although a relationship among AQP4-Ab levels, disease activity, and response to RTX was observed, the usefulness of AQP4-Ab titration to predict relapses is limited.

Dear Editor, We describe the case of a woman with acute onset of confusion and restlessness and lymphocytic pleocytosis in the cerebrospinal fluid (CSF). In the previous days she had several episodes of headache and transient focal neurological deficits. The syndrome of transient headache and neurologic deficits with cerebrospinal fluid lymphocytosis (HaNDL) is a benign, self-limited condition characterized by episodes of severe headache, transient neurological deficit and lymphocytic pleocytosis in the CSF [1, 2]. Confusional state is a very rare clinical manifestation of the syndrome [3]. We report the case of a 40-year-old woman, with a history of left renal colic in 2013 and dysplasia of the cervix (CIN3) treated with loop electrosurgical excision in 2012. She had no previous history of migraine. In May 2014, she began to complain of lateral homonymous right hemianopia, intense frontal throbbing headache associated with nausea and vomiting, phonophobia and photophobia. The headache did not increase with exertion. The visual deficit completely receded in 1 h but the headache persisted. After few hours, she developed transient focal neurological deficit, characterized by paresthesias of the right upper limb and right perioral region. The headache lasted until the next day. She did not have febrile illness or infection before the onset of the disorder. During the following days she experienced again intense throbbing headache unresponsive to common analgesics associated with vomit, phonophobia and photophobia. She also developed confusion and restlessness. Therefore, she went to the ER. At admission she showed marked restlessness and aggressiveness, which improved after sedation in few hours. Neurological examination showed neither focal neurologic signs nor meningeal irritation. The patient had memories of the episodes of neurological impairment but she had no memory of her confusional state. Brain CT was normal. Brain Magnetic Resonance Imaging (MRI) did not reveal any abnormal findings on T1-weighted or T2-weighted images, gadolinium enhancement, diffusion-weighted images, fluid-attenuated inversion recovery (FLAIR) images. Electroencephalography did not reveal any abnormal findings including epileptic abnormal waves. Specific tests excluded intoxications (alcohol serum, dibucaine and cannabinoids serum and urine) or infections. CSF examination showed lymphocytic pleocytosis M. Lo Re (&) Department of Experimental Medicine and Clinical Neuroscience, University of Palermo, Palermo, Italy e-mail: marianna.lore@gmail.com

Background: Glatiramer acetate (GA) in multiple sclerosis acts through the induction of GA-specific T-helper 2 cells. Nevertheless, the phenomenon is not universal in patients, explaining individual differences in clinical response. Objective: The objective of this article was to categorize GA-treated patients. Method: An enhanced quantitative PCR assay was used for measuring ex-vivo GA-induced IFNγ and IL4 mRNA responses in mononuclear cells from 23 healthy donors, 27 untreated patients, 33 short-term (≤6 months) and 77 long-term (>6 months) GA-treated patients. Thresholds for IFNγ and IL4 transcriptional response were calculated by ROC analysis and long-term treated patients were compared in terms of prognostic stratification. Results: Thresholds for IFNγ and IL4 transcriptional response were calculated at 5.36 and 1.41 relative expression (RE). Finally, 67% of long-term treated patients scored above both response thresholds. These patients had a higher proportion of relapse-free subjects (74% vs 40% when compare to patients who scored below both thresholds) and a significantly better relapse-free survival rate ( p=0.006; CI 0.29–0.75). The negative predictive value to predict adverse clinical outcome was 79% (CI 0.63–0.90), meaning that by a positive response, there is a 79% chance that the patient will not experience a negative outcome at 3 years. Conclusions: Our enhanced quantitative PCR assay produced clinically significant results for GA-treated patients. As such, if patients have a positive response, it means they have less chance of a relapse, while patients with a negative response have a greater probability of a worse outcome.

MxA is an antiviral protein induced by type I interferons (IFN) and some viruses; MxA gene expression is an appropriate marker for measuring biologic activity of exogenous IFNβ, as its induction indicates IFNAR receptor stimulation. A recent study has shown that measurement of MxA mRNA, after 1 year of treatment, predicts clinical responsiveness to IFNβ therapy. Loss of IFNβ bioactivity is mostly due to anti-IFNβ antibodies (both neutralizing and binding), non-compliance and receptor saturation. The aim of this study was to evaluate all possible causes of loss of IFNβ bioactivity after 1 year in treated patients. One hundred sixty-seven multiple sclerosis (MS) patients were included. One year after beginning IFNβ therapy, each patient underwent a blood test; MxA gene expression was measured by real time PCR, antiviral CPE assay to detect neutralizing antibodies (NAbs), and capture-ELISA (cELISA) to measure binding antibodies (BAbs). For MxA an upper normal threshold of 87 (RE) was considered, 20 TRU/mL was the threshold for NAbs, and 1 U for BAbs positivity. Thirty-seven out of 167 patients (22%) were MxA-negative; of these, 22 were both BAbs and NAbs+, whereas 12 were BAbs+ but Nabs-, and three were both BAbs and NAbs-. The following conclusions were drawn from the study: (1) MxA mRNA should be measured after 1 year of IFNβ therapy; (2) after 1 year of IFNβ treatment, absence of IFNβ bioactivity was detected in 22% of the patients; (3) different biological phenomena and reduced compliance explain this absence; (4) identification of the reason for absence of IFN bioactivity improves patients' management.

The current study presents a western blot assay showing good sensitivity (81%) and specificity (97%) for detecting serum antibodies to Aquaporin-4 (AQP4) in patients with Neuromyelitis Optica (NMO). By using western blot, we were able, for the first time, to distinguish serum immunoreactivity against either of the two AQP4 isoforms, showing that antibodies recognizing the linear AQP4-M1 isoform are specific for NMO. Moreover, the high sensitivity and specificity of the western blot assay in detecting serum anti-AQP4 antibodies in NMO patients suggest that such auto-antibodies may be of linear nature, thus recognizing epitopes that are displayed in denatured protein.

Background: Prolonged therapy with interferon β (IFNβ) often leads to the development of anti-IFNβ binding antibodies (BAbs). A subset of the BAbs is of a neutralizing nature (neutralizing antibodies, NAbs) and is associated with reduced clinical efficacy of therapy. Myxovirus-resistance-protein A (MxA) has proven to be a reliable biomarker of IFNβ bioactivity. We analyzed the prognostic value of MxA mRNA, NAbs, and BAbs on the risk of having a new relapse in IFNβ-treated patients. Methods: A 3-year study was conducted in 137 IFNβ-treated patients. Blood samples for BAbs, NAbs, and MxA mRNA measurements were taken after 12 ± 3 months of therapy. Analysis of relapse-free survival (RFS) was performed for all measures by using known thresholds, generating “positive” and “negative” groups. Also, time between sampling and following relapse and risk of new relapses were calculated. Results: The MxA-negative group showed poorer RFS rates than the MxA-positive group [ p p = 0.0013; HR = 2.49). On the contrary, BAb measurement did not show a clear clinical significance. Conclusions: Findings indicate that measurements of both myxovirus-resistance-protein A (MxA) and neutralizing antibodies (NAbs) predict the risk of new relapses; however, the slightly stronger prognostic significance of MxA mRNA and the easier method for it measurement make MxA mRNA the preferred biomarker for monitoring interferon β (IFNβ)-treated patients. This information can be used to better tailor treatment to the individual patient with MS. GLOSSARY: BAb = binding antibody; CPE = cytopathic effect; EDSS = Expanded Disability Status Scale; GAPDH = glyceraldehyde phosphate dehydrogenase; HR = hazard ratio; IFN = interferon; MxA = myxovirus-resistance-protein A; NAb = neutralizing antibody; RFS = relapse-free survival; ROC = receiver operating characteristic; TRU = 10-fold reduction units.