Protection of homologous and heterologous boosters after primary schemes of rAd26-rAd5, ChAdOx1 nCoV-19 and BBIBP-CorV during the omicron outbreak in adults of 50 years and older in Argentina: a test-negative case-control study.

Background: After primary vaccination schemes with rAd26-rAd5 (Sputnik V), ChAdOx1 nCoV-19, BBIBP-CorV or heterologous combinations, the effectiveness of homologous or heterologous boosters (Sputnik V, ChAdOx, Pfizer-BioNTech, Moderna) against SARS-CoV-2 infections, hospitalisations and deaths has been scarcely studied. Methods: Test-negative, case-control study, conducted in Argentina during omicron BA.1 predominance, in adults ≥50 years old tested for SARS-CoV-2 who had received two or three doses of COVID-19 vaccines. Outcomes were COVID-associated infections, hospitalisations and deaths after administering mRNA and vectored boosters, < or ≥60 days from the last dose. Findings: Of 422,124 individuals tested for SARS-CoV-2, 221,993 (52.5%) tested positive; 190,884 (45.2%) and 231,260 (54.8%) had received 2-dose and 3-dose vaccination schemes, respectively. The 3-dose scheme reduced infections, hospitalisations and death (OR 0.81 [0.80-0.83]; 0.28 [0.25-0.32] and 0.25 [0.22-0.28] respectively), but protection dropped after 60 days to 1.04 [1.01-1.06]; 0.52 [0.44-0.61] and 0.38 [0.33-0.45]). Compared with 2-dose-schemes, homologous boosters after primary schemes with vectored-vaccines provided lower protection against infections < and ≥60 days (0.94 [0.92-0.97] and 1.05 [1.01-1.09], respectively) but protected against hospitalisations (0.30 [0.26-0.35]) and deaths (0.29 [0.25-0.33]), decreasing after 60 days (0.59 [0.47-0.74] and 0.51 [0.41-0.64], respectively). Heterologous boosters protected against infections (0.70 [0.68-0.71]) but decreased after 60 days (1.01 [0.98-1.04]) and against hospitalisations and deaths (0.26 [0.22-0.31] and 0.22 [0.18-0.25], respectively), which also decreased after 60 days (0.43 [0.35-0.53] and 0.33 [0.26-0.41], respectively). Heterologous boosters protected against infections when applied <60 days (0.70 [0.68-0.71], p < 0.001), against hospitalisations when applied ≥60 days (0.43 [0.35-0.53], p < 0.01), and against deaths < and ≥60 days (0.22 [0.18-0.25], p < 0.01 and 0.33 [0.26-0.41], p < 0.001). Interpretation: During omicron predominance, heterologous boosters such as viral vectored and mRNA vaccines, following Sputnik V, ChAdOx1, Sinopharm or heterologous primary schemes might provide better protection against death; this effect might last longer in individuals aged ≥50 than homologous boosters. Funding: None.

EpiGe: A machine-learning strategy for rapid classification of medulloblastoma using PCR-based methyl-genotyping.

Molecular classification of medulloblastoma is critical for the treatment of this brain tumor. Array-based DNA methylation profiling has emerged as a powerful approach for brain tumor classification. However, this technology is currently not widely available. We present a machine-learning decision support system (DSS) that enables the classification of the principal molecular groups-WNT, SHH, and non-WNT/non-SHH-directly from quantitative PCR (qPCR) data. We propose a framework where the developed DSS appears as a user-friendly web-application-EpiGe-App-that enables automated interpretation of qPCR methylation data and subsequent molecular group prediction. The basis of our classification strategy is a previously validated six-cytosine signature with subgroup-specific methylation profiles. This reduced set of markers enabled us to develop a methyl-genotyping assay capable of determining the methylation status of cytosines using qPCR instruments. This study provides a comprehensive approach for rapid classification of clinically relevant medulloblastoma groups, using readily accessible equipment and an easy-to-use web-application.t.

Efectividad de refuerzos homólogos y heterólogos luego de esquemas primarios con Sputnik V, Astra-Zeneca y Sinopharm durante el período omicron en adultos mayores de 50 años en la provincia de Buenos Aires / Effectiveness of homologous and heterologous boosters after primary regimens with Sputnik V, AstraZeneca, and Sinopharm during the omicron variant period in adults over 50 years old in the province of Buenos Aires

Objetivo: Evaluar la efectividad de esquemas primarios de Sputnik V, Astra-Zeneca, Sinopharm o combinaciones heterólogas seguidos de refuerzos a vector viral (Sputnik V, Astra-Zeneca) o ARNm (Pfizer-BioNTech, Moderna) frente a infecciones, hospitalizaciones y muertes por SARS-CoV-2. Material y métodos: Estudio de casos y controles con test negativo realizado en la provincia de Buenos Aires, durante el predominio de ómicron BA.1, que incluyó individuos ≥ 50 años con test positivo para SARS-CoV-2 que habían recibido 2 o 3 dosis de vacunas. Se registraron infecciones, hospitalizaciones y muertes después de administrar refuerzos con Sputnik V, Astra-Zeneca o ARNm. Resultados: De 422 124 personas analizadas para SARS-Cov-2, 221 993 (52.5%) presentaron test positivos; 190 884 (45.2%) y 231.260 (54.8%) recibieron esquemas de vacunación de 2 y 3 dosis, respectivamente. Los esquemas primarios con Astra-Zeneca, Sputnik V o vector viral, combinados con un refuerzo a vector viral, mostraron protección contra infecciones (OR: 0.94 [0.92 a 0.97]), hospitalizaciones (OR: 0.30 [0.26 a 0.35]) y muertes (OR: 0.29 [0.25 a 0.33]. Los esquemas primarios con Astra-Zeneca y Sputnik V más refuerzo de ARNm, o con Sinopharm más refuerzo de ARNm o vector viral otorgaron protección adicional contra infecciones (OR: 0.70 [0.68 a 0.71]). Hubo un efecto protector frente a hospitalizaciones y muertes (OR: 0.26 [0.22 a 0.31] y 0.22 [0.18 a 0.25]) en todos los casos. Conclusiones: Durante el predominio de ómicron, los refuerzos heterólogos con vacunas a vector viral y de ARNm, posteriores a los esquemas primarios de Sputnik V, Astra-Zeneca, Sinopharm o heterólogos, podrían proporcionar mejor protección y mayor duración del efecto contra la muerte en personas mayores de 50 años, en comparación con refuerzos homólogos

Objective: To evaluate the effectiveness of primary vaccination regimens involving Sputnik V, Astra-Zeneca, Sinopharm, or heterologous combinations followed by viral vector boosters (Sputnik V, As-traZeneca) or mRNA boosters (Pfizer-BioNTech, Moderna) against infections, hospitalizations and deaths caused by SARS-CoV-2. Material and methods: Case-control studies with negative tests conducted in the Buenos Aires province during the Omicron BA.1 predominance. The study included patients ≥ 50 years of age, who tested positive for SARS-CoV-2 and had received two or three doses of vaccines. Infections, hospitalizations, and deaths were registered following the administration of Sputnik V, AstraZeneca, or mRNA boosters. Findings: Out of 422 124 people tested for SARS-Cov-2, 221 993 (52.5%) had positive test results; 190,884 (45.2%) and 231 260 (54.8%) received two-dose and three-dose vaccination schemes, respectively. Primary regimens with AstraZeneca, Sputnik V, or viral vector, combined with a viral vector booster demonstrated protection against infections (OR 0.94 [0.92 to 0.97]), hospitalizations (OR 0.30 [0.26 to 0.35]) and deaths (OR 0.29 [0.25 to 0.33]. Primary regimens with AstraZeneca and Sputnik V combined with mRNA boosters, as well as pri-mary schemes with Sinopharm combined with mRNA or viral vectored boosters showed additional protection against infections (OR 0.70 [0.68 to 0.71]). There was a protective effect against hospi-talizations and deaths (OR 0.26 [0.22-0.31] and 0.22 [0.18 -0.25]) in all cases. Conclusions: During Omicron predominance, heterologous boosters with viral-vector and mRNA vaccines, administered after Sputnik V, AstraZeneca, Sinopharm, or heterologous primary regimens, could provide enhanced protection and prolonged effectiveness against mortality in individuals aged ≥ 50, compared to ho-mologous boosters

Safety and immunogenicity of a SARS-CoV-2 Gamma variant RBD-based protein adjuvanted vaccine used as booster in healthy adults.

A Gamma Variant RBD-based aluminum hydroxide adjuvanted vaccine called ARVAC CG was selected for a first in human clinical trial. Healthy male and female participants (18-55 years old) with a complete COVID-19-primary vaccine scheme were assigned to receive two intramuscular doses of either a low-dose or a high-dose of ARVAC CG. The primary endpoint was safety. The secondary objective was humoral immunogenicity. Cellular immune responses were studied as an exploratory objective. The trial was prospectively registered in PRIISA.BA (Registration Code 6564) and ANMAT and retrospectively registered in ClinicalTrials.gov (NCT05656508). Samples from participants of a surveillance strategy implemented by the Ministry of Health of the Province of Buenos Aires that were boosted with BNT162b2 were also analyzed to compare with the booster effect of ARVAC CG. ARVAC CG exhibits a satisfactory safety profile, a robust and broad booster response of neutralizing antibodies against the Ancestral strain of SARS-CoV-2 and the Gamma, Delta, Omicron BA.1 and Omicron BA.5 variants of concern and a booster effect on T cell immunity in individuals previously immunized with different COVID-19 vaccine platforms.

Neural crest-related NXPH1/α-NRXN signaling opposes neuroblastoma malignancy by inhibiting organotropic metastasis.

Neuroblastoma is a pediatric cancer that can present as low- or high-risk tumors (LR-NBs and HR-NBs), the latter group showing poor prognosis due to metastasis and strong resistance to current therapy. Whether LR-NBs and HR-NBs differ in the way they exploit the transcriptional program underlying their neural crest, sympatho-adrenal origin remains unclear. Here, we identified the transcriptional signature distinguishing LR-NBs from HR-NBs, which consists mainly of genes that belong to the core sympatho-adrenal developmental program and are associated with favorable patient prognosis and with diminished disease progression. Gain- and loss-of-function experiments revealed that the top candidate gene of this signature, Neurexophilin-1 (NXPH1), has a dual impact on NB cell behavior in vivo: whereas NXPH1 and its receptor α-NRXN1 promote NB tumor growth by stimulating cell proliferation, they conversely inhibit organotropic colonization and metastasis. As suggested by RNA-seq analyses, these effects might result from the ability of NXPH1/α-NRXN signalling to restrain the conversion of NB cells from an adrenergic state to a mesenchymal one. Our findings thus uncover a transcriptional module of the sympatho-adrenal program that opposes neuroblastoma malignancy by impeding metastasis, and pinpoint NXPH1/α-NRXN signaling as a promising target to treat HR-NBs.

Utilización precoz de tocilizumab en pacientes internados con COVID-19 grave y crítica: un estudio multicéntrico en la Provincia de Buenos Aires / Early use of tocilizumab in hospitalized patients with severe and critical COVID-19 in the Province of Buenos Aires: a multicentric study

Resumen Introducción: El objetivo principal del estudio fue evaluar la mortalidad en los pacientes con COVID-19 graves y críticos, que recibieron tocilizumab (TCZ) -un antagonista monoclonal del receptor de IL-6- de forma temprana vs. tardía. Métodos: Cohorte retrospectiva multicéntrica de pacientes >18 años internados con COVID-19 desde el 1/7/2021-1/8/2022, con 5-7 puntos de gravedad inicial (GI) según Escala de la OMS. Se consideró adminis tración temprana o tardía a la infusión de TCZ ≤ ó > a 48 h del ingreso. Las variables de resultado fueron mortalidad a 28 días y cambio de la GI. Los factores relacionados con la mortalidad fueron evaluados con regresión de Cox. Resultados: Se incluyeron 266 pacientes, 159(60%) varones; edad 58(± 15); con hipertensión arterial (43%), obesidad (37%) y diabetes (27%);70 presentaban GI = 5 (oxígeno suplementario), 143 GI = 6 (ventilación no inva siva o cánula nasal de alto flujo) y 53 GI = 7 (ventilación mecánica invasiva). La mortalidad a 28 días fue 42%, asociada independientemente a: edad, obesidad, GI, días entre la internación y administración del TCZ, y días entre la fecha de inicio de síntomas y el TCZ. La mortalidad para GI 5, 6 y 7 fue 26%, 39% y 72%, respectivamente; 76% y 62% de los pacientes permanecieron estables o mejoraron la GI a los días 3 y 7 de la infusión de TCZ. La mortalidad a 28 días fue 39% (TCZ temprano) vs. 57% (TCZ tardío); p = 0.02; HR = 0.63[0.41-0.99, p = 0.05]). Discusión: Estos resultados apoyan la administración temprana de TCZ en pacientes con COVID-19 grave y crítica.

Abstract Introduction: Tocilizumab (TCZ), an IL-6 receptor antagonist monoclonal antibody is warranted in severe and critically-ill COVID-19 patients. The objective was to evaluate 28-day mortality of patients with severe or critical COVID-19 treated with early vs delayed TCZ. Methods: Multicenter, retrospective cohort study in cluding patients>18 years hospitalized between 7/1/2021- 8/1/2022 with confirmed COVID-19, with 5, 6 and 7 points of WHO Ordinal Initial Severity Scale [SS]. Early or late administration was considered if TCZ was administered before or after 48 hours from admission. Outcomes were28-day mortality and change of SS. Factors related to 28-day mortality were evaluated with Cox regression. Results: 266 patients were included, 159(60%) male; aged 58(± 15); frequent comorbidities were hypertension (42%), obesity (37%) and diabetes (27%). Seventy patients had a SS = 5 (Supplemental O2), 143 had SS = 6 (NIV/ HFNC), and 53 had SS = 7 (IMV). 28-day mortality was 42%(112/266); predictors were age, obesity, higher SS, days between hospitalization and TCZ administration, and fewer days between symptoms onset and TCZ. Mortality of SS 5, 6 and 7 was 26%, 39% and 72% respectively. Com pared with baseline SS points, 76% and 62% of patients remained stable or improved on days 3 and 7 since TCZ administration. 28-day mortality was lower when TCZ was administered before 48 hours (39% vs 57%; p = 0.02; HR = 0.63;[0.41-0.99, p = 0.05]). Discussion: This study supports the early use of TCZ in patients with severe or critical COVID-19.

[Early use of tocilizumab in hospitalized patients with severe and critical COVID-19 in the Province of Buenos Aires: a multicentric study]. / Utilización precoz de tocilizumab en pacientes internados con COVID-19 grave y crítica: un estudio multicéntrico en la Provincia de Buenos Aires.

INTRODUCTION: Tocilizumab (TCZ), an IL-6 receptor antagonist monoclonal antibody is warranted in severe and critically-ill COVID-19 patients. The objective was to evaluate 28-day mortality of patients with severe or critical COVID-19 treated with early vs delayed TCZ. METHODS: Multicenter, retrospective cohort study including patients >18 years hospitalized between 7/1/2021-8/1/2022 with confirmed COVID-19, with 5, 6 and 7 points of WHO Ordinal Initial Severity Scale [SS]. Early or late administration was considered if TCZ was administered before or after 48 hours from admission. Outcomes were 28-day mortality and change of SS. Factors related to 28-day mortality were evaluated with Cox regression. RESULTS: 266 patients were included, 159(60%) male; aged 58(± 15); frequent comorbidities were hypertension (42%), obesity (37%) and diabetes (27%). Seventy patients had a SS = 5 (Supplemental O2), 143 had SS = 6 (NIV/ HFNC), and 53 had SS = 7 (IMV). 28-day mortality was 42%(112/266); predictors were age, obesity, higher SS, days between hospitalization and TCZ administration, and fewer days between symptoms onset and TCZ. Mortality of SS 5, 6 and 7 was 26%, 39% and 72% respectively. Compared with baseline SS points, 76% and 62% of patients remained stable or improved on days 3 and 7 since TCZ administration. 28-day mortality was lower when TCZ was administered before 48 hours (39% vs 57%; p = 0.02; HR = 0.63;[0.41-0.99, p = 0.05]). DISCUSSION: This study supports the early use of TCZ in patients with severe or critical COVID-19.

Introducción: El objetivo principal del estudio fue evaluar la mortalidad en los pacientes con COVID-19 graves y críticos, que recibieron tocilizumab (TCZ) -un antagonista monoclonal del receptor de IL-6- de forma temprana vs. tardía. Métodos: Cohorte retrospectiva multicéntrica de pacientes > 18 años internados con COVID-19 desde el 1/7/2021-1/8/2022, con 5-7 puntos de gravedad inicial (GI) según Escala de la OMS. Se consideró administración temprana o tardía a la infusión de TCZ = ó > a 48 h del ingreso. Las variables de resultado fueron mortalidad a 28 días y cambio de la GI. Los factores relacionados con la mortalidad fueron evaluados con regresión de Cox. Resultados: Se incluyeron 266 pacientes, 159(60%) varones; edad 58(± 15); con hipertensión arterial (43%), obesidad (37%) y diabetes (27%);70 presentaban GI = 5 (oxígeno suplementario), 143 GI = 6 (ventilación no invasiva o cánula nasal de alto flujo) y 53 GI = 7 (ventilación mecánica invasiva). La mortalidad a 28 días fue 42%, asociada independientemente a: edad, obesidad, GI, días entre la internación y administración del TCZ, y días entre la fecha de inicio de síntomas y el TCZ. La mortalidad para GI 5, 6 y 7 fue 26%, 39% y 72%, respectivamente; 76% y 62% de los pacientes permanecieron estables o mejoraron la GI a los días 3 y 7 de la infusión de TCZ. La mortalidad a 28 días fue 39% (TCZ temprano) vs. 57% (TCZ tardío); p = 0.02; HR = 0.63[0.41-0.99, p = 0.05]). Discusión: Estos resultados apoyan la administración temprana de TCZ en pacientes con COVID-19 grave y crítica.

A miRNA signature related to stemness identifies high-risk patients in paediatric acute myeloid leukaemia.

Clinical and biological variables like genetic aberrations at diagnosis and the levels of measurable residual disease (MRD) are the most powerful biomarkers to predict the outcome of paediatric leukaemia. Recently, a model integrating the genetic abnormalities, transcriptional identity, and leukaemia stemness measured as leukaemic stem cell score (pLSC6) has been proposed to identify high-risk paediatric acute myeloid leukaemia (AML) patients. However, the role of epigenetics in defining prognosis still needs to be established. We evaluated the role of 89 miRNAs regulating stemness and their contribution to predicting outcomes in 110 paediatric patients with acute leukaemia. We identified a 24-miRNA signature capable of distinguishing paediatric AML patients with excellent or poor outcomes. We validated these results in an independent cohort using public repository-based data. The 24-miRNA signature was significantly associated with the leukaemic stemness scores and the underlying genetics of patients. Notably, the combination of classical prognostic factors (MRD and genetics), the pLSC6 score and the 24-miRNA signature had a higher capacity to predict the overall and event-free survival than each variable individually. Our 24-miRNA signature provides epigenetic data to integrate into genetics, MRD and stemness-related leukaemic scores to refine risk stratification in paediatric AML patients.

Follow-up of intraocular retinoblastoma through the quantitative analysis of conserved nuclear DNA sequences in aqueous humor from patients.

Fundoscopy is the standard method for diagnosis and follow-up of intraocular retinoblastoma, but it is sometimes insufficient to discern whether tumors are inactivated following treatments. In this work, we hypothesized that the amount of conserved nuclear DNA sequences in the cell-free DNA (cfDNA) fraction of the aqueous humor (AH) might complement fundoscopy for retinoblastoma follow-up. To address our hypothesis, we developed highly sensitive droplet digital polymerase chain reaction (ddPCR) methods to quantify highly conserved DNA sequences of nucleus-encoded genes (GAPDH and B4GALNT1) and of a mitochondrial gene, MT-ATP6. We obtained AH samples during intravitreal treatments. We analyzed 42 AH samples from 25 patients with intraocular retinoblastoma and 11 AH from controls (non-cancer patients). According to clinical criteria, we grouped patients as having progression-free or progressive retinoblastoma. cfDNA concentration in the AH was similar in both retinoblastoma groups. Copy counts for nucleus-derived sequences of GAPDH and B4GALNT1 were significantly higher in the AH from patients with progressive disease, compared to the AH from progression-free patients and control non-cancer patients. The presence of mitochondrial DNA in the AH explained that both retinoblastoma groups had similar cfDNA concentration in AH. The optimal cut-off point for discriminating between progressive and progression-free retinoblastomas was 108 GAPDH copies per reaction. Among patients having serial AH samples analyzed during their intravitreal chemotherapy, GAPDH copies were high and decreased below the cut-off point in those patients responding to chemotherapy. In contrast, one non-responder patient remained with values above the cut-off during follow-up, until enucleation. We conclude that the measurement of conserved nuclear gene sequences in AH allows follow-up of intraocular retinoblastoma during intravitreal treatment. The method is applicable to all patients and could be relevant for those in which fundoscopy evaluation is inconclusive.

Effectiveness of BBIBP-CorV, BNT162b2 and mRNA-1273 vaccines against hospitalisations among children and adolescents during the Omicron outbreak in Argentina: A retrospective cohort study.

Background: Although paediatric clinical presentations of COVID-19 are usually less severe than in adults, serious illness and death have occurred. Many countries started the vaccination rollout of children in 2021; still, information about effectiveness in the real-world setting is scarce. The aim of our study was to evaluate vaccine effectiveness (VE) against COVID-19-associated-hospitalisations in the 3-17-year population during the Omicron outbreak. Methods: We conducted a retrospective cohort study including individuals aged 3-17 registered in the online vaccination system of the Buenos Aires Province, Argentina. mRNA-1273 and BNT162b2 were administered to 12-17-year subjects; and BBIBP-CorV to 3-11-year subjects. Vaccinated group had received a two-dose scheme by 12/1/2021. Unvaccinated group did not receive any COVID-19 vaccine between 12/14/2021 and 3/9/2022, which was the entire monitoring period. Vaccine effectiveness (VE) against COVID-19-associated hospitalisations was calculated as (1-OR)x100. Findings: By 12/1/2021, 1,536,435 individuals aged 3-17 who had received zero or two doses of SARS-CoV-2 vaccines were included in this study. Of the latter, 1,440,389 were vaccinated and 96,046 not vaccinated. VE were 78.0%[68.7-84.2], 76.4%[62.9-84.5] and 80.0%[64.3-88.0] for the entire cohort, 3-11-year (BBIBP-CorV) subgroup and 12-17 (mRNA vaccines) subgroup, respectively. VE for the entire population was 82.7% during the period of Delta and Omicron overlapping circulation and decreased to 67.7% when Omicron was the only variant present. Interpretation: This report provides evidence of high vaccine protection against associated hospitalisations in the paediatric population during the Omicron outbreak but suggests a decrease of protection when Omicron became predominant. Application of a booster dose in children aged 3-11-year warrants further consideration. Funding: None.

MIF/CXCR4 signaling axis contributes to survival, invasion, and drug resistance of metastatic neuroblastoma cells in the bone marrow microenvironment.

BACKGROUND: The bone marrow (BM) is the most common site of dissemination in patients with aggressive, metastatic neuroblastoma (NB). However, the molecular mechanisms underlying the aggressive behavior of NB cells in the BM niche are still greatly unknown. In the present study, we explored biological mechanisms that play a critical role in NB cell survival and progression in the BM and investigated potential therapeutic targets. METHODS: Patient-derived bone marrow (BM) primary cultures were generated using fresh BM aspirates obtained from NB patients. NB cell lines were cultured in the presence of BM conditioned media containing cell-secreted factors, and under low oxygen levels (1% O2) to mimic specific features of the BM microenvironment of high-risk NB patients. The BM niche was explored using cytokine profiling assays, cell migration-invasion and viability assays, flow cytometry and analysis of RNA-sequencing data. Selective pharmacological inhibition of factors identified as potential mediators of NB progression within the BM niche was performed in vitro and in vivo. RESULTS: We identified macrophage migration inhibitory factor (MIF) as a key inflammatory cytokine involved in BM infiltration. Cytokine profiling and RNA-sequencing data analysis revealed NB cells as the main source of MIF in the BM, suggesting a potential role of MIF in tumor invasion. Exposure of NB cells to BM-conditions increased NB cell-surface expression of the MIF receptor CXCR4, which was associated with increased cell viability, enhanced migration-invasion, and activation of PI3K/AKT and MAPK/ERK signaling pathways. Moreover, subcutaneous co-injection of NB and BM cells enhanced tumor engraftment in mice. MIF inhibition with 4-IPP impaired in vitro NB aggressiveness, and improved drug response while delayed NB growth, improving survival of the NB xenograft model. CONCLUSIONS: Our findings suggest that BM infiltration by NB cells may be mediated, in part, by MIF-CXCR4 signaling. We demonstrate the antitumor efficacy of MIF targeting in vitro and in vivo that could represent a novel therapeutic target for patients with disseminated high-risk NB.

AC-265347 Inhibits Neuroblastoma Tumor Growth by Induction of Differentiation without Causing Hypocalcemia.

Neuroblastoma is the most common extracranial solid tumor of childhood, with heterogeneous clinical manifestations ranging from spontaneous regression to aggressive metastatic disease. The calcium-sensing receptor (CaSR) is a G protein-coupled receptor (GPCR) that senses plasmatic fluctuation in the extracellular concentration of calcium and plays a key role in maintaining calcium homeostasis. We have previously reported that this receptor exhibits tumor suppressor properties in neuroblastoma. The activation of CaSR with cinacalcet, a positive allosteric modulator of CaSR, reduces neuroblastoma tumor growth by promoting differentiation, endoplasmic reticulum (ER) stress and apoptosis. However, cinacalcet treatment results in unmanageable hypocalcemia in patients. Based on the bias signaling shown by calcimimetics, we aimed to identify a new drug that might exert tumor-growth inhibition similar to cinacalcet, without affecting plasma calcium levels. We identified a structurally different calcimimetic, AC-265347, as a promising therapeutic agent for neuroblastoma, since it reduced tumor growth by induction of differentiation, without affecting plasma calcium levels. Microarray analysis suggested biased allosteric modulation of the CaSR signaling by AC-265347 and cinacalcet towards distinct intracellular pathways. No upregulation of genes involved in calcium signaling and ER stress were observed in patient-derived xenografts (PDX) models exposed to AC-265347. Moreover, the most significant upregulated biological pathways promoted by AC-265347 were linked to RHO GTPases signaling. AC-265347 upregulated cancer testis antigens (CTAs), providing new opportunities for CTA-based immunotherapies. Taken together, this study highlights the importance of the biased allosteric modulation when targeting GPCRs in cancer. More importantly, the capacity of AC-265347 to promote differentiation of malignant neuroblastoma cells provides new opportunities, alone or in combination with other drugs, to treat high-risk neuroblastoma patients.

Timing of convalescent plasma administration and 28-day mortality in COVID-19 pneumonia.

This is a multicenter cohort study including consecutive, hospitalized patients ≥18 years, with moderate to severe COVID-19, carried out to evaluate the relationship between the timing of convalescent plasma administration and 28-day mortality. Data were prospectively collected between May 14, 2020 and October 31, 2020. Patients were grouped according to the timing of administration of convalescent plasma as <3 days, between 3 and 7 days, and >7 days. The main outcome variable was 28-day mortality. Independent predictors of mortality were identified by logistic regression. Of 4719 patients receiving convalescent plasma, 3036 (64.3%) were in the general ward, 1171 (24.8%) in the intensive care unit (ICU), and 512 (10.8%) in the ICU on mechanical ventilation. Convalescent plasma was administered to 3113 (66%) patients within the first 3 days of hospital admission, to 1380 (29.2%) between 3 and 7 days, and to 226 after 7 days; 28-day mortality was, respectively, 18.1%, 30.4% and 38.9% (p<0.001). In the regression model, convalescent plasma administration within the first 3 days of admission was associated with reduced 28-day mortality, compared with the administration after 7 days (OR 0.40, 95% CI 0.30 to 0.53). Early convalescent plasma administration was associated to a significant decreased mortality in patients in the general ward (OR 0.45, 95% CI 0.29 to 0.69) and in the ICU (OR 0.35, 95% CI 0.19 to 0.64), but not in those requiring mechanical ventilation (OR 0.52, 95% CI 0.27 to 1.01). In conclusion, this study suggests that early administration of convalescent plasma to patients with COVID-19 pneumonia is critical to obtain therapeutic benefit.

SPARC-mediated long-term retention of nab-paclitaxel in pediatric sarcomas.

Secreted protein acidic and rich in cysteine (SPARC) is a matricellular glycoprotein overexpressed by several cancers. Because SPARC shows high binding affinity to albumin, we reasoned that pediatric sarcoma xenografts expressing SPARC would show enhanced uptake and accumulation of nanoparticle albumin-bound (nab)-paclitaxel, a potent anticancer drug formulation. We first evaluated the expression of SPARC in patient-derived xenografts (PDXs) of Ewing sarcoma, rhabdomyosarcoma and osteosarcoma, finding variable SPARC gene expression that correlated well with SPARC protein measured by immunoblotting. We revealed that the activity of the fusion gene chimera EWSR1-FLI1, the genetic driver of Ewing sarcoma, leads to lower expression of the gene SPARC in these tumors, likely due to enriched acetylation marks of the histone H3 lysine 27 at regions including the SPARC promoter and potential enhancers. Then, we used SPARC-edited Ewing sarcoma cells (A673 line) to demonstrate that SPARC knocked down (KD) cells accumulated significantly less amount of nab-paclitaxel in vitro than SPARC wild type (WT) cells. In vivo, SPARC KD and SPARC WT subcutaneous xenografts in mice achieved similar maximum intratumoral concentrations of nab-paclitaxel, though drug clearance from SPARC WT tumors was significantly slower. We confirmed such SPARC-mediated long-term intratumoral accumulation of nab-paclitaxel in Ewing sarcoma PDX with high expression of SPARC, which accumulated significantly more nab-paclitaxel than SPARC-low PDX. SPARC-high PDX responded better to nab-paclitaxel than SPARC-low tumors, although these results should be taken cautiously, given that the PDXs were established from different patients that could have specific determinants predisposing response to paclitaxel. In addition, SPARC KD Ewing sarcoma xenografts responded better to soluble docetaxel and paclitaxel than to nab-paclitaxel, while SPARC WT ones showed similar response to soluble and albumin-carried drugs. Overall, our results show that pediatric sarcomas expressing SPARC accumulate nab-paclitaxel for longer periods of time, which could have clinical implications for chemotherapy efficacy.

Cysteine-Rich Secretory Proteins (CRISP) are Key Players in Mammalian Fertilization and Fertility.

Mammalian fertilization is a complex process involving a series of successive sperm-egg interaction steps mediated by different molecules and mechanisms. Studies carried out during the past 30 years, using a group of proteins named CRISP (Cysteine-RIch Secretory Proteins), have significantly contributed to elucidating the molecular mechanisms underlying mammalian gamete interaction. The CRISP family is composed of four members (i.e., CRISP1-4) in mammals, mainly expressed in the male tract, present in spermatozoa and exhibiting Ca2+ channel regulatory abilities. Biochemical, molecular and genetic approaches show that each CRISP protein participates in more than one stage of gamete interaction (i.e., cumulus penetration, sperm-ZP binding, ZP penetration, gamete fusion) by either ligand-receptor interactions or the regulation of several capacitation-associated events (i.e., protein tyrosine phosphorylation, acrosome reaction, hyperactivation, etc.) likely through their ability to regulate different sperm ion channels. Moreover, deletion of different numbers and combination of Crisp genes leading to the generation of single, double, triple and quadruple knockout mice showed that CRISP proteins are essential for male fertility and are involved not only in gamete interaction but also in previous and subsequent steps such as sperm transport within the female tract and early embryo development. Collectively, these observations reveal that CRISP have evolved to perform redundant as well as specialized functions and are organized in functional modules within the family that work through independent pathways and contribute distinctly to fertility success. Redundancy and compensation mechanisms within protein families are particularly important for spermatozoa which are transcriptionally and translationally inactive cells carrying numerous protein families, emphasizing the importance of generating multiple knockout models to unmask the true functional relevance of family proteins. Considering the high sequence and functional homology between rodent and human CRISP proteins, these observations will contribute to a better understanding and diagnosis of human infertility as well as the development of new contraceptive options.

Effectiveness of Telephone Monitoring in Primary Care to Detect Pneumonia and Associated Risk Factors in Patients with SARS-CoV-2.

Improved technology facilitates the acceptance of telemedicine. The aim was to analyze the effectiveness of telephone follow-up to detect severe SARS-CoV-2 cases that progressed to pneumonia. A prospective cohort study with 2-week telephone follow-up was carried out March 1 to May 4, 2020, in a primary healthcare center in Barcelona. Individuals aged ≥15 years with symptoms of SARS-CoV-2 were included. Outpatients with non-severe disease were called on days 2, 4, 7, 10 and 14 after diagnosis; patients with risk factors for pneumonia received daily calls through day 5 and then the regularly scheduled calls. Patients hospitalized due to pneumonia received calls on days 1, 3, 7 and 14 post-discharge. Of the 453 included patients, 435 (96%) were first attended to at a primary healthcare center. The 14-day follow-up was completed in 430 patients (99%), with 1798 calls performed. Of the 99 cases of pneumonia detected (incidence rate 20.8%), one-third appeared 7 to 10 days after onset of SARS-CoV-2 symptoms. Ten deaths due to pneumonia were recorded. Telephone follow-up by a primary healthcare center was effective to detect SARS-CoV-2 pneumonias and to monitor related complications. Thus, telephone appointments between a patient and their health care practitioner benefit both health outcomes and convenience.

Effectiveness of the first component of Gam-COVID-Vac (Sputnik V) on reduction of SARS-CoV-2 confirmed infections, hospitalisations and mortality in patients aged 60-79: a retrospective cohort study in Argentina.

BACKGROUND: A first-dose of various vaccines provides acceptable protection against infections by SARS-CoV-2 and evolution to the most severe forms of COVID-19. The recombinant adenovirus (rAd)-based vaccine, Gam-COVID-Vac (Sputnik V), was proven efficacious but information about effectiveness in the real-world setting is lacking. The aim of our study was to investigate the association between the rollout of the first component (rAd26) of Gam-COVID-Vac and PCR-positive tests, hospitalisations and deaths. METHODS: We conducted a retrospective cohort study which analyzed individuals aged 60-79 who self-registered in the online vaccination system of the Province of Buenos Aires, Argentina, from December 29, 2020 to March 21, 2021. Exclusion criteria were having a previous positive RT-PCR or antigen tests for SARS-CoV-2, having received other vaccines, or two doses of any vaccine.Proportions of new laboratory-confirmed SARS-CoV-2 infections, hospitalisations and deaths until 83 days of vaccination were compared between vaccinated and unvaccinated subjects. Vaccine effectiveness for the three outcomes was calculated as (1-OR) × 100. Kaplan-Meier cumulative incidence curves were constructed. FINDINGS: During the study period 415995 registered subjects received the first component of Gam-COVID-Vac; 40387 belonged to the 60-79 age group, and were compared to 38978 unvaccinated. Vaccine effectiveness for preventing laboratory-confirmed infections was 78•6% [CI95% 74·8 - 81·7]; and for reducing hospitalizations and deaths was, respectively, 87·6% [CI95% 80·3 - 92·2] and 84·8% [CI95% 75·0 - 90·7]. Effectiveness was high across all subgroups. INTERPRETATION: Similarly to other vaccines, the administration of one dose of Gam-COVID-Vac was effective for a wide range of COVID-19-related outcomes. FUNDING: This study did not receive any funding.

Pharmacological Inactivation of CatSper Blocks Sperm Fertilizing Ability Independently of the Capacitation Status of the Cells: Implications for Non-hormonal Contraception.

Cation channel of sperm (CatSper), the main sperm-specific Ca2+ channel, plays a key role in mammalian fertilization, and it is essential for male fertility, becoming an attractive target for contraception. Based on this, in the present work, we investigated the effects of CatSper inactivation on in vitro and in vivo sperm fertilizing ability and the mechanisms underlying such effects. Exposure of cauda epididymal mouse sperm to different concentrations (1-20 µM) of the potent CatSper inhibitor HC-056456 (HC) during in vitro capacitation showed no effects on sperm viability but significantly affected Ca2+ entry into the cells, progressive motility, protein tyrosine phosphorylation, induced acrosome reaction, and hyperactivation, as well as the sperm's ability to in vitro fertilize cumulus oocyte complexes and zona-free eggs. Whereas the presence of HC during gamete coincubation did not affect in vitro fertilization, exposure of either non-capacitating or already capacitated sperm to HC prior to gamete coincubation severely reduced fertilization, indicating that sperm function is affected by HC when the cells are incubated with the drug before sperm-egg interaction. Of note, insemination of HC-treated sperm into the uterus significantly or completely reduced the percentage of oviductal fertilized eggs showing, for the first time, the effects of a CatSper inhibitor on in vivo fertilization. These observations, together with the finding that HC affects sperm fertilizing ability independently of the sperm capacitation status, provide further insights on how CatSper regulates sperm function and represent a solid proof of concept for developing a male/female non-hormonal contraceptive based on the pharmacological blockage of CatSper activity.

Risk factors for COVID-19 mortality: The effect of convalescent plasma administration.

BACKGROUND: Convalescent plasma, widely utilized in viral infections that induce neutralizing antibodies, has been proposed for COVID-19, and preliminary evidence shows that it might have beneficial effect. Our objective was to determine the risk factors for 28-days mortality in patients who received convalescent plasma for COVID-19 compared to those who did not, who were admitted to hospitals in Buenos Aires Province, Argentina, throughout the pandemic. METHODS: This is a multicenter, retrospective cohort study of 2-month duration beginning on June 1, 2020, including unselected, consecutive adult patients with diagnosed COVID-19, admitted to 215 hospitals with pneumonia. Epidemiological and clinical variables were registered in the Provincial Hospital Bed Management System. Convalescent plasma was supplied as part of a centralized, expanded access program. RESULTS: We analyzed 3,529 patients with pneumonia, predominantly male, aged 62±17, with arterial hypertension and diabetes as main comorbidities; 51.4% were admitted to the ward, 27.1% to the Intensive Care Unit (ICU), and 21.7% to the ICU with mechanical ventilation requirement (ICU-MV). 28-day mortality was 34.9%; and was 26.3%, 30.1% and 61.4% for ward, ICU and ICU-MV patients. Convalescent plasma was administered to 868 patients (24.6%); their 28-day mortality was significantly lower (25.5% vs. 38.0%, p<0.001). No major adverse effects occurred. Logistic regression analysis identified age, ICU admission with and without MV requirement, diabetes, and preexistent cardiovascular disease as independent predictors of 28-day mortality, whereas convalescent plasma administration acted as a protective factor. CONCLUSIONS: Our study suggests that the administration of convalescent plasma in COVID-19 pneumonia admitted to the hospital might be associated with improved outcomes.