RRM2 enhances MYCN-driven neuroblastoma formation and acts as a synergistic target with CHK1 inhibition

High-risk neuroblastoma, a pediatric tumor originating from the sympathetic nervous system, has a low mutation load but highly recurrent somatic DNA copy number variants. Previously, segmental gains and/or amplifications allowed identification of drivers for neuroblastoma development. Using this approach, combined with gene dosage impact on expression and survival, we identified ribonucleotide reductase subunit M2 (RRM2) as a candidate dependency factor further supported by growth inhibition upon in vitro knockdown and accelerated tumor formation in a neuroblastoma zebrafish model coexpressing human RRM2 with MYCN. Forced RRM2 induction alleviates excessive replicative stress induced by CHK1 inhibition, while high RRM2 expression in human neuroblastomas correlates with high CHK1 activity. MYCN-driven zebrafish tumors with RRM2 co-overexpression exhibit differentially expressed DNA repair genes in keeping with enhanced ATR-CHK1 signaling activity. In vitro, RRM2 inhibition enhances intrinsic replication stress checkpoint addiction. Last, combinatorial RRM2-CHK1 inhibition acts synergistic in high-risk neuroblastoma cell lines and patient-derived xenograft models, illustrating the therapeutic potential

Incidence of Zika virus infection in a prospective cohort of Belgian travellers to the Americas in 2016

BACKGROUND: The incidence rate of Zika virus (ZIKV) infection in travellers from non-endemic areas to the Americas during the ZIKV outbreak in 2016 is unknown. METHODS: Belgian adults who planned to travel to South America, Central America, and the Caribbean were recruited prospectively to study the incidence and characteristics of ZIKV. Demographic data and sera were collected at baseline. Participants were trained to collect capillary blood on filter paper (BFP). When ill during travel, the participants completed a questionnaire and they sampled BFP for post-hoc analysis. All symptomatic participants were screened for ZIKV using ZIKV-specific RT-PCR on serum or urine, or BFP, and antibody detection assays (ELISA). Follow-up sera of asymptomatic travellers, obtained at least 20 days post travel, were tested by ZIKV ELISA only. All positive ELISA results were subject to confirmation by virus neutralization testing (VNT). RESULTS: Forty-nine participants completed follow-up: 38 women and 11 men, with a median age of 32 years (range 19-64 years). Travel destinations were countries in South America (n=20), Central America (n=24), and the Caribbean (n=5). The total travel duration was 67.8 person-months. Illness was reported by 24 participants (49.0%). ZIKV infection was confirmed in nine cases, by RT-PCR (n=5) and by VNT (n=4). Only one of nine ZIKV cases (11.1%) was asymptomatic. The ZIKV incidence rate was 17.0% (95% confidence interval 7.8-32.2%) per month of travel. CONCLUSIONS: The ZIKV incidence rate in adult travellers from non-endemic countries to the epidemic territories during the 2016 outbreak was high. Asymptomatic ZIKV infection was rare in this population.status: publishe

Chikungunya virus infection in Aruba: Diagnosis, clinical features and predictors of post-chikungunya chronic polyarthralgia

BACKGROUND: Chikungunya virus (CHIKV) emerged in Aruba for the first time in 2014. We studied the clinical presentation of acute CHIKV infection and the contribution of serologic and molecular assays to its diagnosis. In a cohort of confirmed CHIKV cases, we analysed the frequency, duration and predictors of post-chikungunya chronic polyarthralgia (pCHIK-CPA), defined as joint pains lasting longer than 6 weeks or longer than 1 year. METHODOLOGY: Patient sera obtained within 10 days of symptom onset were tested for CHIKV, using an indirect immunofluorescence test for the detection of CHIKV-specific Immunoglobulin M (IgM) and post-hoc, by reverse-transcription polymerase chain reaction (RT-PCR). CHIKV was isolated from selected samples and genotyped. For confirmed CHIKV cases, clinical data from chart review were complemented by a Telephone survey, conducted 18-24 months after diagnosis. When joint pain was reported, the duration, presence of inflammatory signs, type and number of joints affected, were recorded. Joint involvement was scored according to the 2010 'American College of Rheumatology/ European League Against Rheumatism' criteria for seronegative rheumatoid arthritis (ACR-score). Risk factors for pCHIK-CPA were identified by logistic regression. PRINCIPAL FINDINGS: Acute CHIKV infection was diagnosed in 269 of 498 sera, by detection of IgM (n = 105), by RT-PCR (n = 59), or by both methods (n = 105). Asian genotype was confirmed in 7 samples. Clinical data were complete for 171 of 248 (69.0%) patients, aged 15 years or older (median 49.4 [35.0-59.6]). The female-to-male ratio was 2.2. The main acute symptoms were arthralgia (94%), fever (85%), myalgia (85%), headache (73%) and rash (63%). In patients with arthralgia (n = 160), pCHIK-CPA longer than 6 weeks was reported by 44% and longer than 1 year by 26% of cases. Inflammatory signs, stiffness, edema and redness were frequent (71%, 39% and 21%, respectively). Joints involved were knees (66%), ankles (50%), fingers (52%), feet (46%), shoulders (36%), elbows (34%), wrists (35%), hips (31%), toes (28.1%) and spine (28.1%). Independent predictors of pCHIK-CPA longer than 1 year were female gender (OR 5.9, 95%-CI [2.1-19.6]); high ACR-score (7.4, [2.7-23.3]), and detection of CHIKV-RNA in serum beyond 7 days of symptom onset (6.4, [1.4-34.1]. CONCLUSIONS: We identified 269 CHIKV patients after the first outbreak of Asian genotype CHIKV in Aruba in 2014-2015. RT-PCR yielded 59 (28%) additional CHIKV diagnoses compared to IgM antibody detection alone. Arthralgia, fever and skin rash were the dominant acute phase symptoms. pCHIK-CPA longer than 1 year affected 26% of cases and was predicted by female gender, high ACR-score and CHIKV-RNA detection beyond 7 days of symptom onset.status: publishe

I nutraceutici nell'area metabolica

Le malattie cardiovascolari (CVD) sono la causa più comune di decesso nei paesi occidentali. Tra i parametri di rischio CVD, la dislipidemia è un fattore rilevante e modificabile: in particolare l’associazione di ipertrigliceridemia, bassi livelli di HDL-C, aumentate concentrazioni di LDL-C piccole e dense e di apoB, viene definita “dislipidemia aterogena” essendo molto pericolosa da un punto di vista metabolico. Le dislipidemie sono condizioni abbastanza diffuse e il loro riconoscimento e trattamento dei pazienti a rischio costituisce un intervento importante sia in prevenzione primaria che secondaria. Le modificazioni dello stile di vita e dell’alimentazione costituiscono la prima linea di intervento ma, quando non è possibile raggiungere i target terapeutici per ridurre il rischio CVD agendo su questi fattori, può apparire utile l’utilizzo di prodotti “nutraceutici”. I nutraceutici sono componenti alimentari attivi, che presentano attività terapeutica e di prevenzione, presenti negli alimenti funzionali ma generalmente utilizzati, a fini terapeutici, sotto forma di loro concentrati (pillole, capsule, fiale). Questa tesi è basata sui risultati di un protocollo di studio della durata di circa 3 anni che prevedeva la valutazione ed il confronto di più nutraceutici in commercio, con differenti concentrazioni di Monacolina K estratta da Riso Rosso Fermentato. L’obiettivo era quello di verificare se fosse presente un effetto dose-dipendente della Monacolina K sui parametri lipido- e glicometabolici in pazienti con Sindrome Metabolica, più specificamente nei dislipidemici e nei diabetici di tipo 2 con dislipidemia

Targeted AURKA degradation: towards new therapeutic agents for neuroblastoma

Aurora kinase A (AURKA) is a well-established target in neuroblastoma (NB) due to its catalytic functions during mitosis and due to stabilisation of the key oncoprotein MYCN. We report a small structure-activity relationship (SAR) study of MK-5108-derived PROTACs against AURKA by exploring different linker lengths and both the 4- and 5-position as thalidomide exit vectors. PROTAC SK2188 induces the most potent AURKA degradation (DC50, 24h < 10 nM, Dmax, 1h 98%, Dmax, 24h, 80%) and significantly outperforms the parent inhibitor MK-5108 in a cell proliferation screen and patient-derived organoids. Treatment of NGP neuroblastoma cells with SK2188 induced concomitant MYCN degradation, high replication stress/DNA damage levels and apoptosis. Furthermore, altering the attachment point of the PEG linker to the 5-position of thalidomide allowed us to identify a potent AURKA degrader with a linker as short as 2 PEG units. With this, our SAR-study provides interesting lead structures for further optimization and validation of AURKA degradation as a potential therapeutic strategy in neuroblastoma

Targeted AURKA degradation: Towards new therapeutic agents for neuroblastoma

Aurora kinase A (AURKA) is a well-established target in neuroblastoma (NB) due to both its catalytic functions during mitosis and its kinase-independent functions, including stabilization of the key oncoprotein MYCN. We present a structure-activity relationship (SAR) study of MK-5108-derived PROTACs against AURKA by exploring different linker lengths and exit vectors on the thalidomide moiety. PROTAC SK2188 induces the most potent AURKA degradation (DC50,24h 3.9 nM, Dmax,24h 89%) and shows an excellent binding and degradation selectivity profile. Treatment of NGP neuroblastoma cells with SK2188 induced concomitant MYCN degradation, high replication stress/DNA damage levels and apoptosis. Moreover, SK2188 significantly outperforms the parent inhibitor MK-5108 in a cell proliferation screen and patient-derived organoids. Furthermore, altering the attachment point of the PEG linker to the 5-position of thalidomide allowed us to identify a potent AURKA degrader with a linker as short as 2 PEG units. With this, our SAR-study provides interesting lead structures for further optimization and validation of AURKA degradation as a potential therapeutic strategy in neuroblastoma.Aurora kinase A (AURKA) is a well-established target in neuroblastoma (NB) due to both its catalytic functions during mitosis and its kinase-independent functions, including stabilization of the key oncoprotein MYCN. We present a structure-activity relationship (SAR) study of MK-5108-derived PROTACs against AURKA by exploring different linker lengths and exit vectors on the thalidomide moiety. PROTAC SK2188 induces the most potent AURKA degradation (DC50,24h 3.9 nM, Dmax,24h 89%) and shows an excellent binding and degradation selectivity profile. Treatment of NGP neuroblastoma cells with SK2188 induced concomitant MYCN degradation, high replication stress/DNA damage levels and apoptosis. Moreover, SK2188 significantly outperforms the parent inhibitor MK-5108 in a cell proliferation screen and patient-derived organoids. Furthermore, altering the attachment point of the PEG linker to the 5-position of thalidomide allowed us to identify a potent AURKA degrader with a linker as short as 2 PEG units. With this, our SAR-study provides interesting lead structures for further optimization and validation of AURKA degradation as a potential therapeutic strategy in neuroblastoma.A

Pattern of joint involvement, inflammatory symptoms and pain duration in chikungunya virus infected patients presenting with arthralgia (n = 160).

<p>Pattern of joint involvement, inflammatory symptoms and pain duration in chikungunya virus infected patients presenting with arthralgia (n = 160).</p

Number of samples collected for chikungunya diagnostics per epidemiological week, during the outbreak in Aruba from October 2014 –March 2015 (n = 498).

<p>Note: epiweek 6 and 7 coincided with Carnival, Aruba’s public holiday.</p

Characteristics of 171 patients with confirmed chikungunya infection.

<p>Characteristics of 171 patients with confirmed chikungunya infection.</p