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1.
Neurocase ; 21(6): 721-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25372555

RESUMEN

The role of the cerebellum in cognitive performance and attentional processes is a focus of research in recent years. We investigated the P300 component in a patient with a left posterior cerebellar ischemic stroke during both the acute phase and over 4 weeks of follow-up. After stroke, auditory event-related potentials showed a reduction in P3 amplitude, which appears to improve instead after 4 weeks of follow-up. These event-related potential findings could suggest a specific neural pattern of disruption in selective attention during the discrimination processes of the stimulus following a posterior cerebellar lesion. A recovery is observed in the long term.


Asunto(s)
Atención/fisiología , Isquemia Encefálica/fisiopatología , Enfermedades Cerebelosas/fisiopatología , Corteza Cerebral/fisiopatología , Potenciales Relacionados con Evento P300 , Accidente Cerebrovascular/fisiopatología , Estimulación Acústica , Isquemia Encefálica/complicaciones , Isquemia Encefálica/psicología , Enfermedades Cerebelosas/complicaciones , Enfermedades Cerebelosas/psicología , Electroencefalografía , Potenciales Evocados Auditivos , Humanos , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Pruebas Neuropsicológicas , Recuperación de la Función , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/psicología
2.
Neural Plast ; 2015: 410785, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26090234

RESUMEN

Phasic alertness represents the ability to increase response readiness to a target following an external warning stimulus. Specific networks in the frontal and parietal regions appear to be involved in the alert state. In this study, we examined the role of the right dorsolateral prefrontal cortex (DLPFC) during the attentional processing of a stimulus using a cued double-choice reaction time task. The evaluation of these processes was conducted by means of Event-Related Potentials (ERPs), in particular by using the Contingent Negative Variation (CNV), and repetitive 1-Hz Transcranial Magnetic Stimulation (rTMS). Transient virtual inhibition of the right DLPFC induced by real 1-Hz rTMS stimulation led to a significant decrease in total CNV and W1-CNV areas if compared with the basal and post-sham rTMS conditions. Reaction times (RTs) did not decrease after inhibitory rTMS, but they did improve after sham stimulation. These results suggest that the right DLPFC plays a crucial role in the genesis and maintenance of the alerting state and learning processes.


Asunto(s)
Atención/fisiología , Corteza Prefrontal/fisiología , Vigilia , Adulto , Conducta de Elección/fisiología , Señales (Psicología) , Electroencefalografía , Femenino , Lateralidad Funcional , Humanos , Masculino , Inhibición Neural , Desempeño Psicomotor/fisiología , Tiempo de Reacción , Estimulación Magnética Transcraneal/métodos , Adulto Joven
3.
Clin Ther ; 46(2): 164-172, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38092583

RESUMEN

The lack of harmonization in the post-approval changes (PACs) classifications for pharmaceutical products may have an impact on the efficient implementation of PACs and in the supply of medicine, jeopardizing the continuity of therapies, especially in the case of chronic diseases. The percentage of similarity between the PACs classifications existing between countries of Latin America (Mexico, Brazil, Colombia, Venezuela, Argentina, Chile, Ecuador, Peru, and Central America) versus Europe and the United States (US) has been calculated, focused on the PACs for chemical products and on the minor and moderate variations as defined in the European Union (EU)1,2 and US3 regulations. Even though Mexico, Colombia, Brazil, and Argentina implemented a risk-based PACs classification, a wide diversity is observed, with a high percentage of variations classified as major or high risk for these countries and the rest of the Latin American countries, except for Venezuela (which previously adopted and recognized the EU classification). In addition, we identified a group/subset of PACs that are not categorized in the regulations of Mexico, Brazil, Chile, and Central America countries. Considering that Mexico, Brazil, and Argentina are members or observers of the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use4 and the Pharmaceutical Inspection Co-operation Scheme,5 these countries could further align their PACs classification with the EU and US regulations. This could also be an opportunity for other countries of the Latin America region to recognize and adopt PACs classifications aligned to the EU or United States, which would also support the inclusion of reliance processes in their regulation for already considered/recognized reference countries. This would guarantee more health authority efficiency and optimization as well as more uniform implementation of PACs globally.


Asunto(s)
Confianza , Estados Unidos , Humanos , América Latina , México , Brasil , Europa (Continente)
4.
J Immunother Cancer ; 11(4)2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37117006

RESUMEN

BACKGROUND: Tumor microenvironment (TME) represents a critical hurdle in cancer immunotherapy, given its ability to suppress antitumor immunity. Several efforts are made to overcome this hostile TME with the development of new therapeutic strategies modifying TME to boost antitumor immunity. Among these, cytokine-based approaches have been pursued for their known immunomodulatory effects on different cell populations within the TME. IL-12 is a potent pro-inflammatory cytokine that demonstrates striking immune activation and tumor control but causes severe adverse effects when systemically administered. Thus, local administration is considered a potential strategy to achieve high cytokine concentrations at the tumor site while sparing systemic adverse effects. METHODS: Modified Vaccinia Ankara (MVA) vector is a potent inducer of pro-inflammatory response. Here, we cloned IL-12 into the genome of MVA for intratumoral immunotherapy, combining the immunomodulatory properties of both the vector and the cargo. The antitumor activity of MVA-IL-12 and its effect on TME reprogramming were investigated in preclinical tumor models. RNA sequencing (RNA-Seq) analysis was performed to assess changes in the TME in treated and distal tumors and the effect on the intratumoral T-cell receptor repertoire. RESULTS: Intratumoral injection of MVA-IL-12 resulted in strong antitumor activity with the complete remission of established tumors in multiple murine models, including those resistant to checkpoint inhibitors. The therapeutic activity of MVA-IL-12 was associated with very low levels of circulating cytokine. Effective TME reprogramming was demonstrated on treatment, with the reduction of immunosuppressive M2 macrophages while increasing pro-inflammatory M1, and recruitment of dendritic cells. TME switch from immunosuppressive into immunostimulatory environment allowed for CD8 T cells priming and expansion leading to tumor attack. CONCLUSIONS: Intratumoral administration of MVA-IL-12 turns immunologically 'cold' tumors 'hot' and overcomes resistance to programmed cell death protein-1 blockade.


Asunto(s)
Interleucina-12 , Neoplasias , Humanos , Ratones , Animales , Interleucina-12/genética , Interleucina-12/farmacología , Microambiente Tumoral , Virus Vaccinia/genética , Citocinas/metabolismo , Neoplasias/patología
5.
Clin Ther ; 44(8): 1107-1128, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35798570

RESUMEN

For more than a decade, the World Health Organization, Pan American Health Organization, Pan-American Network or Drug Regulatory Harmonization, and the International Conference of Drug Regulatory Authorities, have encouraged regulators to adopt reliance and recognition pathways to reduce duplication, improve efficiency and efficacy, and strengthen regulatory capabilities, in order to facilitate marketing authorization approval, thereby maintaining supply chain integrity. Several factors have limited the more widespread implementation of reliance pathways in Latin America, among which is having the appropriate legal tools in place between and among agencies. Key among these tools are the Memorandum of Understanding (MOU) and cooperation agreements. Herein we have reviewed the content and the characteristics of MOUs and cooperation agreements available on the official websites of the regulatory agencies of the region (we found 11 multilateral MOUs and 8 cooperation agreements published), signed by Latin American agencies and interregional organizations. In this commentary, common characteristics are identified and recommendations for further implementation are made to promote communication, information sharing, and trust, thereby supporting the broader use of reliance pathways in the region.


Asunto(s)
Organizaciones , Organización Panamericana de la Salud , Humanos , América Latina
6.
Parkinsonism Relat Disord ; 98: 80-85, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35526494

RESUMEN

BACKGROUND: Non-genetic risk factors play a relevant role in Parkinson's disease (PD) development but the relationship between these factors and PD clinical features is unknown. OBJECTIVE: The aim of the present multicenter study was to investigate possible relationship between risk factors and clinical motor and non-motor features in a large sample of PD patients. METHODS: Six hundred ninety-four patients with PD participated. Patients underwent a clinical evaluation assessing motor symptoms and motor complications as well as non-motor symptoms severity. Information regarding pharmacological treatment was also collected. Risk and protective factors were previously identified in the present population and included coffee consumption, cigarette smoking, and physical activity as protective factors and a family history of PD, dyspepsia, exposure to toxic agents and general anesthesia as risk factors. Multiple regression models were used to investigate the relationship between risk factors and clinical variables. RESULTS: Coffee consumption predicted older age at onset (B: 0.527; CI: 0.195; 0.858) and milder motor symptom severity (B: 1.383; CI: 2.646; -0.121). Non-motor symptom severity was more severe in patients with dyspepsia before PD (B: 13.601; CI 5.019; 22.182) and milder in patients who performed physical activity before PD (B: 11.355; CI: 16.443; -6.266). We found no relationship between risk factors and motor complications, motor subtype and pharmacological treatment. CONCLUSIONS: Risk and protective factors of PD development may influence PD clinical features. This finding may represent the first step in the development of new preventive approaches able to delay disease onset and mitigate the extent of clinical manifestations.


Asunto(s)
Dispepsia , Enfermedad de Parkinson , Edad de Inicio , Café/efectos adversos , Dispepsia/complicaciones , Humanos , Enfermedad de Parkinson/complicaciones , Factores Protectores , Factores de Riesgo
7.
Front Med (Lausanne) ; 8: 768376, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34888329

RESUMEN

In recent years, post-approval changes (PACs) for medicinal products have increased faster than the national regulatory agencies can attend to without causing any negative impact. This study presents a proposal for regulatory management based on our analysis of the data available from the national regulatory agencies of Latin America on the total post-approval changes evaluated, and the time spent in the process. A retrospective search on the official websites of competent national regulatory authorities (NRAs) of 14 Latin American countries (México, Guatemala, Nicaragua, Honduras, El Salvador, Panamá, Costa Rica, Venezuela, Colombia, Ecuador, Peru, Argentina, Chile and Brazil) was conducted to collect data on post-approval changes in the last 4-6 years, up to January 2021. The NRAs considered were Brazil, México, Colombia, and Costa Rica. Our analysis was focused on the post-approval changes that required approval before implementation, those that were submitted, and those that were submitted and approved for small molecules, biologics, and biotechnological products. The results indicated differences in the regulatory processes and procedures applied by the different agencies. We also found that the implementation of the PACs was directly impacted by limited resources, which puts the medication supply for chronic treatments at risk resulting in serious consequences for patients. For local decision-making, Latin American NRAs should implement regulatory pathways already made by regulatory agencies included in the World Health Organization Listed Authorities on PAC approval to optimize their resources and to ensure the continuity of medicine supply for their patients.

8.
Clin Ther ; 43(1): 124-139, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33353762

RESUMEN

PURPOSE: Crucial steps have been adopted by health and regulatory authorities around the world to respond to the COVID-19 pandemic. This review aims to highlight these steps by providing an overview of the regulatory approaches adopted during the onset of the pandemic, provide an assessment of observed trends, and offer some reflections and proposals to leverage learnings and opportunities from this current pandemic. METHODS: Documents and informational materials on regulating the development and management of medical products during the COVID-19 pandemic were collected and classified. These materials were sourced from official websites and press releases from health authorities and international bodies from selected markets across the globe, and covered the period between January and July 2020. Additional information to support this study was gathered through a literature review and analysis of related data available from the public domain, and was complemented with the authors' personal experience. FINDINGS: Communication has been vital in addressing the impact of COVID-19. A total of 1705 documents and informational materials related to health or regulatory response to the COVID-19 pandemic were gathered. Of these, 343 (around 20%) were identified as regulatory agilities. These agile approaches were classified into 3 categories, namely, where health and regulatory authorities had: (1) facilitated product management across the entire lifecycle, notably in expediting medical product use for COVID-19, ensuring the continuity of clinical trials, and addressing supply chain issues; (2) strengthened international cooperation; and (3) addressed regulatory burden with the adoption of electronic and digital tools. IMPLICATIONS: While many regulatory measures have been introduced temporarily as a response to the COVID-19 crisis, there are opportunities for leveraging an understanding from these approaches in order to collectively achieve more efficient regulatory systems and to mitigate and address the impact of COVID-19 and further future-proof the regulatory environment.


Asunto(s)
COVID-19 , Comunicación , Aprobación de Recursos , Aprobación de Drogas , Política Pública , Asociación entre el Sector Público-Privado , Ensayos de Uso Compasivo , Control de Medicamentos y Narcóticos , Política de Salud , Humanos , Legislación de Dispositivos Médicos , Pandemias , SARS-CoV-2 , Factores de Tiempo
9.
Vaccines (Basel) ; 9(8)2021 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-34452005

RESUMEN

Neoantigens are tumor-specific antigens able to induce T-cell responses, generated by mutations in protein-coding regions of expressed genes. Previous studies demonstrated that only a limited subset of mutations generates neoantigens in microsatellite stable tumors. We developed a method, called VENUS (Vaccine-Encoded Neoantigens Unrestricted Selection), to prioritize mutated peptides with high potential to be neoantigens. Our method assigns to each mutation a weighted score that combines the mutation allelic frequency, the abundance of the transcript coding for the mutation, and the likelihood to bind the patient's class-I major histocompatibility complex alleles. By ranking mutated peptides encoded by mutations detected in nine cancer patients, VENUS was able to select in the top 60 ranked peptides, the 95% of neoantigens experimentally validated including both CD8 and CD4 T cell specificities. VENUS was evaluated in a murine model in the context of vaccination with an adeno vector encoding the top ranked mutations prioritized in the MC38 cell line. Efficacy studies demonstrated anti tumoral activity of the vaccine when used in combination with checkpoint inhibitors. The results obtained highlight the importance of a combined scoring system taking into account multiple features of each tumor mutation to improve the accuracy of neoantigen prediction.

10.
J Immunother Cancer ; 9(11)2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34824160

RESUMEN

BACKGROUND: A number of different immune pathways are involved in the effective killing of cancer cells, collectively named as the 'Cancer Immunity Cycle'. Anti-PD-1 checkpoint blockade (CPB) therapy is active on one of these pathways and reinvigorates anticancer T cell immunity, leading to long-term responses in a limited fraction of patients with cancer. We have previously shown that neoantigens-based adenovirus vectored vaccine in combination with anti-PD-1 further expands pre-existing anticancer immunity and elicits novel neoantigen-specific T cells thereby increasing efficacy to 50% of tumor clearance in mice. Here we added a third component to the CPB plus vaccine combination, which is able to modify the suppressive tumor microenvironment by reducing the number of tumor-infiltrating regulatory T cells (Tregs), as strategy for improving the therapeutic efficacy and overcoming resistance. METHODS: The antitumor efficacy of anti-PD-1, neoantigen vaccine and Treg modulating agents, either Bempegaldesleukin (BEMPEG: NKTR-214) or an anti-CTLA-4 mAb with Treg-depleting activity, was investigated in murine tumor models. We evaluated tumor growth in treated animals, neoantigen-specific T cells in tumors, tumor-infiltrating lymphocytes (TILs) and intratumoral Tregs. RESULTS: The addition of BEMPEG or anti-CTLA-4 to the combination of vaccine and anti-PD-1 led to complete eradication of large tumors in nearby 100% of treated animals, in association with expansion and activation of cancer neoantigen-specific T cells and reduction of tumor-infiltrating Tregs. CONCLUSION: These data support the notion that the integrated regulation of three steps of the cancer immunity cycle, including expansion of neoantigen-specific T cells, reversal of the exhausted T cell phenotype together with the reduction of intratumoral Tregs may represent a novel rationally designed drug combination approach to achieve higher cure rates.


Asunto(s)
Vacunas contra el Cáncer/inmunología , Expresión Génica/genética , Inmunoterapia/métodos , Receptor de Muerte Celular Programada 1/inmunología , Linfocitos T Reguladores/inmunología , Animales , Femenino , Humanos , Ratones
11.
Cancers (Basel) ; 12(11)2020 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-33213060

RESUMEN

The dichotomic contribution of cancer cell lysis and tumor immunogenicity is considered essential for effective oncovirotherapy, suggesting that the innate antiviral immune response is a hurdle for efficacy of oncolytic viruses. However, emerging evidence is resizing this view. By sensing cytosolic DNA, the cyclic GMP-AMP synthase (cGAS) and stimulator of interferon genes (STING) axis can both counteract viral spread and contribute to the elicitation of adaptive immunity via type I interferon responses. In this paper, we analyzed the tumor-resident function of Sting-mediated DNA sensing in a combined approach of oncovirotherapy and PD-1 immune checkpoint blockade, in an immunocompetent murine model. While supporting increased lytic potential by oncolytic HER2-retargeted HSV-1 in vitro and in vivo, Sting-knockout tumors showed molecular signatures of an immunosuppressive tumor microenvironment. These signatures were correspondingly associated with ineffectiveness of the combination therapy in a model of established tumors. Results suggest that the impairment in antiviral response of Sting-knockout tumors, while favoring viral replication, is not able to elicit an adequate immunotherapeutic effect, due to lack of immunogenic cell death and the inability of Sting-knockout cancer cells to promote anti-tumor adaptive immune responses. Accordingly, we propose that antiviral, tumor-resident Sting provides fundamental contributions to immunotherapeutic efficacy of oncolytic viruses.

12.
Oxid Med Cell Longev ; 2020: 8630275, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32089785

RESUMEN

BACKGROUND: Neurodegenerative diseases (ND) as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis represent a growing cause of disability in the developed countries. The underlying physiopathology is still unclear. Several lines of evidence suggest a role for oxidative stress and NADPH oxidase 2 (NOX2) in the neuropathological pathways that lead to ND. Furthermore, recent studies hypothesized a role for gut microbiota in the neuroinflammation; in particular, lipopolysaccharide (LPS) derived from Gram-negative bacteria in the gut is believed to play a role in causing ND by increase of oxidative stress and inflammation. The aim of this study was to assess NOX2 activity as well as serum 8-iso-prostaglandin F2α (8-iso-PGF2α (8-iso-PGF2. METHODS: One hundred and twenty-eight consecutive subjects, including 64 ND patients and 64 controls (CT) matched for age and gender, were recruited. A cross-sectional study was performed to compare serum activity of soluble NOX2-dp (sNOX2-dp), blood levels of isoprostanes, serum H2O2, and LPS in these two groups. Serum zonulin was used to assess gut permeability. RESULTS: Compared with CT, ND patients had higher values of sNOX2-dp, 8-iso-PGF2α (8-iso-PGF2p < 0.001), zonulin (Rs = 0.411; p < 0.001), zonulin (Rs = 0.411; p < 0.001), zonulin (Rs = 0.411; α (8-iso-PGF2p < 0.001), zonulin (Rs = 0.411; p < 0.001), zonulin (Rs = 0.411; α (8-iso-PGF2p < 0.001), zonulin (Rs = 0.411; ß, 0.459; p < 0.001), zonulin (Rs = 0.411; α (8-iso-PGF2ß, 0.459; p < 0.001), zonulin (Rs = 0.411; R 2 = 57%). CONCLUSION: This study provides the first report attesting that patients with ND have high NOX2 activation that could be potentially implicated in the process of neuroinflammation.


Asunto(s)
Lipopolisacáridos/metabolismo , NADPH Oxidasa 2/metabolismo , Enfermedades Neurodegenerativas/genética , Anciano , Femenino , Humanos , Masculino , Enfermedades Neurodegenerativas/fisiopatología , Estrés Oxidativo
13.
Sci Rep ; 10(1): 4307, 2020 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-32152425

RESUMEN

Oncolytic virotherapy is emerging as a promising therapeutic option for solid tumours. Several oncolytic vectors in clinical testing are based on attenuated viruses; thus, efforts are being taken to develop a new repertoire of oncolytic viruses, based on virulent viral genomes. This possibility, however, raises concerns dealing with the safety features of the virulent phenotypes. We generated a double regulated Herpes simplex type-1 virus (HSV-1), in which tumour cell restricted replicative potential was combined to selective entry via ERBB2 receptor retargeting. The transcriptional control of the viral alpha4 gene encoding for the infected cell protein-4 (ICP4) by the cellular Survivin/BIRC5 promoter conferred a tumour cell-restricted replicative potential to a virulent HSV-1 genome. The combination of the additional ERBB2 retargeting further improved the selectivity for tumour cells, conferring to the double regulated virus a very limited ability to infect and propagate in non-cancerous cells. Accordingly, a suitable replicative and cytotoxic potential was maintained in tumour cell lines, allowing the double regulated virus to synergize in vivo with immune checkpoint (anti-PD-1) blockade in immunocompetent mice. Thus, restricting the replicative spectrum and tropism of virulent HSV-1 genomes by combination of conditional replication and retargeting provides an improved safety, does not alter the oncolytic strength, and is exploitable for its therapeutic potential with immune checkpoint blockade in cancer.


Asunto(s)
Herpesvirus Humano 1/genética , Viroterapia Oncolítica/métodos , Neoplasias Ováricas/terapia , Regiones Promotoras Genéticas , Receptor ErbB-2/metabolismo , Survivin/genética , Replicación Viral , Animales , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/virología , Receptor ErbB-2/genética , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Neurology ; 95(18): e2500-e2508, 2020 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-32943485

RESUMEN

OBJECTIVE: To perform a simultaneous evaluation of potential risk/protective factors of Parkinson disease (PD) to identify independent risk/protective factors, to assess interaction among factors, and to determine whether identified risk factors predict etiologic subtypes of PD. METHODS: We designed a large case-control study assessing 31 protective/risk factors of PD, including environmental and lifestyle factors, comorbid conditions, and drugs. The study enrolled 694 patients with PD and 640 healthy controls from 6 neurologic centers. Data were analyzed by logistic regression models, additive interaction models, and cluster analysis. RESULTS: The simultaneous assessment of 31 putative risk/protective factors of PD showed that only coffee consumption (odds ratio [OR] 0.6; 95% confidence interval [CI] 0.4-0.9), smoking (OR 0.7, 95% CI 0.6-0.9), physical activity (OR 0.8, 95% CI 0.7-0.9), family history of PD (OR 3.2, 95% CI 2.2-4.8), dyspepsia (OR 1.8, 95% CI 1.3-2.4), and exposure to pesticides (OR 2.3, 95% CI1.3-4.2), oils (OR 5.6, 95% CI 2.3-13.7), metals (OR 2.8, 95% CI 1.5-5.4), and general anesthesia (OR 6.1, 95% CI 2.9-12.7) were independently associated with PD. There was no evidence of interaction among risk/protective factors, but cluster analysis identified 4 subtypes with different risk factor profiles. In group 1, all patients had a family history of PD, while dyspepsia or exposure to toxic agents was present in 30% of patients. In groups 2 and 3, a family history of PD was lacking, while exposure to toxic agents (group 2) and dyspepsia (group 3) played major roles. Group 4 consisted of patients with no risk factors. CONCLUSIONS: This study demonstrated that 9 factors independently modify PD risk by coexisting in the same patient rather than interacting with others. Our study suggests the need for future preventive strategies aimed at reducing the coexistence of different risk factors within the same participant.


Asunto(s)
Enfermedad de Parkinson/etiología , Factores Protectores , Factores de Riesgo , Anciano , Estudios de Casos y Controles , Análisis por Conglomerados , Femenino , Humanos , Masculino , Persona de Mediana Edad
15.
Mol Ther Oncolytics ; 19: 253-264, 2020 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-33209980

RESUMEN

Oncolytic viruses (OVs) are novel anti-tumor agents with the ability to selectively infect and kill tumor cells while sparing normal tissue. Beyond tumor cytolysis, OVs are capable of priming an anti-tumor immune response via lysis and cross-presentation of locally expressed endogenous tumor antigens, acting as an "endovaccine." The effectiveness of OVs, similar to other immunotherapies, can be hampered by an immunosuppressive tumor microenvironment. In this study, we modified a previously generated oncolytic herpes simplex virus (oHSV) retargeted to the human HER2 (hHER2) tumor molecule and encoding murine interleukin-12 (mIL-12), by insertion of a second immunomodulatory molecule, murine granulocyte-macrophage colony-stimulating factor (mGM-CSF), to maximize therapeutic efficacy. We assessed the efficacy of this double-armed virus (R-123) compared to singly expressing GM-CSF and IL-12 oHSVs in tumor-bearing mice. While monotherapies were poorly effective, combination with α-PD1 enhanced the anti-tumor response, with the highest efficacy of 100% response rate achieved by the combination of R-123 and α-PD1. Efficacy was T cell-dependent, and the induced immunity was long lasting and able to reject a second contralateral tumor. Importantly, systemic delivery of R-123 combined with α-PD1 was effective in inhibiting the development of tumor metastasis. As such, this approach could have a significant therapeutic impact paving the way for further development of this platform in cancer immunotherapy.

16.
Cancer Res ; 80(18): 3972-3982, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32690723

RESUMEN

Tumors with microsatellite instability (MSI) are caused by a defective DNA mismatch repair system that leads to the accumulation of mutations within microsatellite regions. Indels in microsatellites of coding genes can result in the synthesis of frameshift peptides (FSP). FSPs are tumor-specific neoantigens shared across patients with MSI. In this study, we developed a neoantigen-based vaccine for the treatment of MSI tumors. Genetic sequences from 320 MSI tumor biopsies and matched healthy tissues in The Cancer Genome Atlas database were analyzed to select shared FSPs. Two hundred nine FSPs were selected and cloned into nonhuman Great Ape Adenoviral and Modified Vaccinia Ankara vectors to generate a viral-vectored vaccine, referred to as Nous-209. Sequencing tumor biopsies of 20 independent patients with MSI colorectal cancer revealed that a median number of 31 FSPs out of the 209 encoded by the vaccine was detected both in DNA and mRNA extracted from each tumor biopsy. A relevant number of peptides encoded by the vaccine were predicted to bind patient HLA haplotypes. Vaccine immunogenicity was demonstrated in mice with potent and broad induction of FSP-specific CD8 and CD4 T-cell responses. Moreover, a vaccine-encoded FSP was processed in vitro by human antigen-presenting cells and was subsequently able to activate human CD8 T cells. Nous-209 is an "off-the-shelf" cancer vaccine encoding many neoantigens shared across sporadic and hereditary MSI tumors. These results indicate that Nous-209 can induce the optimal breadth of immune responses that might achieve clinical benefit to treat and prevent MSI tumors. SIGNIFICANCE: These findings demonstrate the feasibility of an "off-the-shelf" vaccine for treatment and prevention of tumors harboring frameshift mutations and neoantigenic peptides as a result of microsatellite instability.


Asunto(s)
Antígenos de Neoplasias/inmunología , Vacunas contra el Cáncer/inmunología , Neoplasias Colorrectales/terapia , Inmunogenicidad Vacunal/inmunología , Inestabilidad de Microsatélites , Animales , Células Presentadoras de Antígenos/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Vacunas contra el Cáncer/genética , Línea Celular Tumoral , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inmunología , Femenino , Mutación del Sistema de Lectura , Humanos , Ratones , Proteínas de Neoplasias/análisis , Proteínas de Neoplasias/inmunología
17.
Chem Res Toxicol ; 22(12): 1922-8, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19894707

RESUMEN

Cafestol and kahweol, coffee-specific furan diterpenes, are believed to cause various physiological effects in human subjects, including an increase in cholesterol and plasma triacylglycerol levels as well as cancer chemopreventive effects. Despite the increasing interest in these compounds raised by the diverse range of biological activities, their reaction behavior and degradation pathways under physiologically relevant conditions remain uncharted. Herein, we report a detailed investigation of the structural modifications suffered by cafestol and kahweol in the presence of acidic nitrite under conditions mimicking those occurring in the stomach during digestion as well as by action of other oxidants. Prior to the chemical study, an isolation procedure for kahweol from green coffee beans was developed based on Soxhlet extraction followed by preparative HPLC. Preliminary experiments showed that kahweol is much more reactive than cafestol toward nitrite at pH 3, as evidenced by inhibition experiments with the 2,3-diaminonaphthalene assay as well as by product analysis in coffee extracts. When exposed to equimolar nitrite in phosphate buffer, pH 3, kahweol gave as a main product the ring-opened dicarbonyl derivative 1. Under more forcing conditions, cafestol reacted as well to give a main nitrogenous product identified as the 1-hydroxy-2-pyrrolinone 2. It is concluded that the conjugated double bond in kahweol is a critical structural element, increasing the susceptibility of the furan ring to protonation rather than nitrosation and favoring ring-opening routes driven by the irreversible oxidation steps. These results offer a useful background to assess the effects of coffee-specific lipids in association with abnormally high nitrite levels from the diet.


Asunto(s)
Diterpenos/química , Nitritos/química , Colesterol/sangre , Cromatografía Líquida de Alta Presión , Café/química , Diterpenos/síntesis química , Diterpenos/aislamiento & purificación , Diterpenos/toxicidad , Furanos/química , Humanos , Concentración de Iones de Hidrógeno , Triglicéridos/sangre
18.
Nat Commun ; 10(1): 2688, 2019 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-31217437

RESUMEN

Neoantigens (nAgs) are promising tumor antigens for cancer vaccination with the potential of inducing robust and selective T cell responses. Genetic vaccines based on Adenoviruses derived from non-human Great Apes (GAd) elicit strong and effective T cell-mediated immunity in humans. Here, we investigate for the first time the potency and efficacy of a novel GAd encoding multiple neoantigens. Prophylactic or early therapeutic vaccination with GAd efficiently control tumor growth in mice. In contrast, combination of the vaccine with checkpoint inhibitors is required to eradicate large tumors. Gene expression profile of tumors in regression shows abundance of activated tumor infiltrating T cells with a more diversified TCR repertoire in animals treated with GAd and anti-PD1 compared to anti-PD1. Data suggest that effectiveness of vaccination in the presence of high tumor burden correlates with the breadth of nAgs-specific T cells and requires concomitant reversal of tumor suppression by checkpoint blockade.


Asunto(s)
Adenoviridae/inmunología , Antineoplásicos Inmunológicos/uso terapéutico , Vacunas contra el Cáncer/uso terapéutico , Neoplasias/terapia , Vacunas Virales/uso terapéutico , Adenoviridae/genética , Animales , Antígenos de Neoplasias/inmunología , Antineoplásicos Inmunológicos/farmacología , Vacunas contra el Cáncer/genética , Vacunas contra el Cáncer/inmunología , Línea Celular Tumoral/trasplante , Terapia Combinada/métodos , Modelos Animales de Enfermedad , Femenino , Humanos , Inmunoterapia/métodos , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Linfocitos Infiltrantes de Tumor/inmunología , Ratones , Neoplasias/inmunología , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/inmunología , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Resultado del Tratamiento , Carga Tumoral/efectos de los fármacos , Carga Tumoral/inmunología , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología , Vacunas Sintéticas/uso terapéutico , Vacunas Virales/genética , Vacunas Virales/inmunología
19.
Photochem Photobiol ; 84(3): 593-9, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18435615

RESUMEN

The characteristic absorption and photochemical properties of pheomelanins are generally attributed to "benzothiazine" structural units derived biogenetically from 5-S-cysteinyldopa. This notion, however, conveys little or no information about the structural chromophores responsible for the photoreactivity of pheomelanins. At pH 7.4, natural and synthetic pheomelanins show a defined maximum around 305 nm, which is not affected by reductive treatment with sodium borohydride, and a monotonic decrease in the absorption in the range 350-550 nm. These features are not compatible with a significant proportion of structural units related to 2H-1,4-benzothiazine and 2H-1,4-benzothiazine-3-carboxylic acid, the early borohydride-reducible pheomelanin precursors featuring absorption maxima above 340 nm. Rather, these features would better accommodate a contribution by the nonreducible 3-oxo-3,4-dihydrobenzothiazine (lambdamax 299 nm) and benzothiazole (lambdamax 303 nm) structural motifs, which are generated in the later stages of pheomelanogenesis in vitro. This conclusion is supported by a detailed liquid chromatography/UV and mass spectrometry monitoring of the species formed in the oxidative conversion of 5-S-cysteinyldopa to pheomelanin, and would point to a critical reassessment of the commonly reported "benzothiazine" chromophore in terms of more specific and substantiated structural units, like those formed during the later stages of pheomelanin synthesis in vitro.


Asunto(s)
Cisteinildopa/química , Melaninas/química , Melanóforos/química , Tiazinas/química , Cromatografía Líquida de Alta Presión , Estructura Molecular , Oxidación-Reducción , Espectrofotometría Ultravioleta
20.
Neuropsychologia ; 84: 127-35, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26878981

RESUMEN

Attentional processing consists of a set of processes that manage the flow of information through the nervous system and appropriately allocate attentional resources to relevant stimuli. Specific networks in the frontal and parietal regions appear to be involved in attention. The cerebellum has been identified as a subcortical structure that interacts with cortical brain areas, thereby controlling attentional processes. The aim of this study was to investigate the role of the cerebellum in attentional processing of the stimulus using a P300 Novelty task. We studied the effects of transcranial Direct Current Stimulation (tDCS) delivered over the left cerebellar hemisphere in cathodal, anodal and sham sessions on the P300 components in healthy subjects. Only cathodal cerebellar tDCS significantly reduced the amplitude of the N1, N2 and P3 components for both the target and novel stimuli. Moreover, N1 latency for all the stimuli was shorter after the cathodal tDCS session than after the sham or anodal sessions. These results point to a role of the cerebellum in attentional processing of the stimulus. The cerebellum may act indirectly by regulating and managing the activation and inhibition levels of the cortical areas involved in attentional networks.


Asunto(s)
Atención/fisiología , Percepción Auditiva/fisiología , Cerebelo/fisiología , Potenciales Evocados/fisiología , Estimulación Transcraneal de Corriente Directa/métodos , Estimulación Acústica/métodos , Adulto , Electroencefalografía , Fatiga/etiología , Fatiga/fisiopatología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Dolor/etiología , Dolor/fisiopatología , Autoinforme , Estimulación Transcraneal de Corriente Directa/efectos adversos
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