Terapia genética de injeção intravítrea de rAAV2-ND4 para neuropatia óptica hereditária de Leber: uma revisão sistemática / rAAV2-ND4 intravitreal injection gene therapy for Leber's hereditary optic neuropathy: a systematic review

RESUMO A neuropatia óptica hereditária de Leber é uma doença mitocondrial hereditária neurodegenerativa. A taxa potencial de recuperação espontânea é controversa na literatura. A terapia genética tem sido estudada como suporte aos pacientes. O objetivo desta revisão foi avaliar qualitativamente a segurança, os efeitos adversos e a eficácia da terapia gênica disponível. Trata-se de uma revisão sistemática de artigos indexados nas bases de dados PubMed®, Biblioteca Virtual em Saúde, SciELO, Cochrane, ScienceDirect, Scopus e Lilacs no primeiro semestre de 2021. Os critérios de inclusão e filtros foram: artigos relacionados ao tema, estudos randomizados, ensaios clínicos, trabalhos em humanos, últimos 5 anos, nas línguas portuguesa, inglesa e espanhola e texto completo disponível gratuitamente. Os parâmetros de exclusão foram: artigos duplicados, fuga ao tema, artigos de revisão, trabalhos não disponíveis e que fugiam aos critérios de inclusão. O coeficiente de kappa foi 0,812. A terapia não apresentou efeitos adversos sérios em nenhum dos artigos selecionados, e os efeitos menores sofreram 100% de remissão espontânea após o tratamento. Apesar de NAbs terem sido encontrados no soro de alguns pacientes, não houve associação entre a resposta imune adaptativa e a injeção do vetor viral. O tratamento foi eficaz na melhora da acuidade e campo visual. Vários estudos confirmaram a eficácia da terapia gênica, em doses baixas e médias, na melhora da acuidade visual e também sobre os efeitos adversos comuns relacionados à altas doses. A resposta imune humoral e a variação dos NAbs no soro foi citada em mais de um artigo. A terapia foi eficaz na melhora da acuidade visual e os efeitos adversos que surgiram foram tratados facilmente. No entanto, a resposta imune humoral ainda precisa ser estudada.

ABSTRACT Leber's Hereditary Optic Neuropathy (LHON) is an inherited neurodegenerative mitochondrial disease. The potential rate of spontaneous recovery is controversial in the literature. Gene therapy has been studied to support patients. The objective of this review was to qualitatively assess the safety, adverse effects, and efficacy of available gene therapy. This is a systematic review of articles indexed in PubMed®, VHL, SciELO, Cochrane, ScienceDirect, Scopus, and Lilacs databases, in the first half of 2021. Inclusion criteria and filters were: articles related to the topic, randomized studies, clinical trials, work in humans, last 5 years, in Portuguese, English, and Spanish and full text available for free. The exclusion parameters were: duplicate articles, not related to the topic, review articles, not available works, and works that did not meet the inclusion criteria. The kappa coefficient was 0.812. The therapy had no serious adverse effects in any of the selected articles, and minor effects experienced 100% spontaneous remission after treatment. Although NAbs were found in the serum of some patients, there was no association between the adaptive immune response and the injection of the viral vector. The treatment was effective in improving acuity and visual field. Several studies have confirmed the effectiveness of gene therapy, at low and medium doses, in improving visual acuity and also on common adverse effects related to high doses. The humoral immune response and the variation in serum NAbs was cited in more than one article. The therapy was effective in improving visual acuity and the adverse effects that arose were easily treated. However, the humoral immune response still needs to be studied.

Antibióticos innovadores contra la farmacorresistencia bacteriana obtenido por tecnología de edición genética CRISPR/Cas9 / Innovative antibiotics against bacterial drug resistance obtained by CRISPR/cas9 gene editing technology

Introducción: El aumento de la resistencia a los antimicrobianos constituye actualmente una peligrosa amenaza para la salud. Ante este problema global de falta de antimicrobianos, es perentorio intervenir de forma coordinada e idear fórmulas para incentivar la investigación a nivel internacional. Objetivo: Realizar una revisión actualizada sobre las causas y mecanismos de la resistencia a los antibióticos y la adaptación del sistema CRISPR/Cas para el desarrollo de innovadores antimicrobianos como parte esencial de una estrategia altamente específica en el tratamiento de infecciones producidas por bacterias resistentes. Métodos: Se realizó una revisión documental, se empleó la bibliografía nacional e internacional especializada publicada en los últimos 5 años. Se utilizó el motor de búsqueda Google Académico y se consultaron artículos de libre acceso en las bases de datos Pubmed, SciELO, LILACS, CUMED y HINARI, en el período comprendido entre marzo de 2020 hasta el mes de enero de 2021. Se revisaron un total de 41 artículos. Las consultas se hicieron en inglés y español. Para la búsqueda se tuvo en cuenta las palabras clave: eligobióticos; resistencia a antibióticos; CRISPR/Cas. Resultados: La evidencia recopilada sustenta que muchas enfermedades son inducidas por alteraciones del equilibrio de la microbiota humana y la técnica de edición genética CRISPR/Cas permitirá el desarrollo de novedosos antibióticos como los eligobióticos que eliminarán las bacterias patógenas multirresistentes y dejarán intacto el microbioma. Conclusiones: el esclarecimiento de los enigmas de la microbiota y su diseño con terapia génica permitirán el progreso de innovadores antibióticos con empleo del sistema CRISPR/Cas que ineludiblemente modificarán la práctica médica para siempre(AU)

Introduction: The increase in antimicrobial resistance is currently a dangerous threat to health. Faced with this global problem of lack of antimicrobials, it is imperative to intervene in a coordinated manner and devise formulas to encourage research at the international level. Objective: To review on the update causes and mechanisms of antibiotic resistance and the adaptation of CRISPR/Cas system for the development of innovative antimicrobials as an essential part of a highly specific strategy in the treatment of infections caused by resistant bacteria. Methods: A documentary review was carried out in the specialized national and international bibliography published in the last 5 years. Google Scholar search engine was used and free access articles were consulted in Pubmed, SciELO, LILACS, CUMED and HINARI databases, from March 2020 to January 2021. A total of 41 articles were retrieved. The consultations were made in English and Spanish. For the search, we took into account the keywords eligobiotics, antibiotic resistance, CRISPR/Cas. Results: The reviewed evidence supports that many diseases are induced by alterations in the balance of the human microbiota; and CRISPR/Cas gene editing technique will allow the development of novel antibiotics such as eligobiotics that will eliminate multi-resistant pathogenic bacteria and leave the microbiome intact. Conclusions: The clarification of the enigmas of the microbiota and its design with gene therapy will allow the progress of innovative antibiotics using CRISPR/Cas system that will inevitably change medical practice forever(AU)

CRISPR-Cas, el editor de genes / CRISPR, gene editor

El término CRISPR, por su acrónimo en inglés refiere a Clustered Regularly Interspaced Short Palindromic Repeats, es decir, repeticiones palindrómicas cortas, agrupadas y regularmente esparcidas, por sus características en el genoma, pertenece naturalmente al sistema de defensa de bacterias y arqueas. Este ha sido adaptado biotecnológicamente para la edición del ADN de células eucariotas, incluso de células humanas. El sistema CRISPR-Cas para editar genes consta, en forma generalizada, de dos componentes: una proteína nucleasa (Cas) y un ARN guía (sgRNA). La simplicidad del complejo lo hace una herramienta molecular reprogramable capaz de ser dirigida y de editar cualquier sitio en un genoma conocido. Su principal foco son las terapias para enfermedades hereditarias monogénicas y para el cáncer. Sin embargo, además de editor de genes, la tecnología CRISPR se utiliza para edición epigenética, regulación de la expresión génica y método de diagnóstico molecular. Este artículo tiene por objetivo presentar una revisión de las aplicaciones de la herramienta molecular CRISPR-Cas, particularmente en el campo biomédico, posibles tratamientos y diagnósticos, y los avances en investigación clínica, utilizando terapia génica con CRISPR/Cas más relevantes hasta la fecha. (AU)

CRISPR are Clustered Regularly Interspaced Short Palindromic Repeats, which naturally belong to the defense system of bacteria and archaea. It has been biotechnologically adapted for editing the DNA of eukaryotic cells, including human cells. The CRISPR-Cas system for editing genes generally consists of two components, a nuclease protein (Cas) and a guide RNA (sgRNA). The simplicity of the complex makes it a reprogrammable molecular tool capable of being targeted and editing any site in a known genome. Its main focus is therapies for monogenic inherited diseases and cancer. However, in addition to gene editor, CRISPR technology is used for epigenetic editing, regulation of gene expression, and molecular diagnostic methods. This article aims to present a review of the applications of the CRISPR-Cas molecular tool, particularly in the biomedical field, possible treatments and diagnoses, and the advances in clinical research, using the most relevant CRISPR-Cas gene therapy to date. (AU)

Respuesta inmune y terapia gó©nica con vectores virales adenoasociados / Immune response and gene therapy with adenoassociated viral vectors

En los ó;ºltimos aó;±os la terapia gó;©nica se ha posicionado como una opció;n real y segura en el desarrollo de alternativas terapó;©uticas para la cura y la prevenció;n de diferentes enfermedades. Consiste en la inserció;n de material genó;©tico en un tejido o có;©lula defectuosa, mediante el uso de un vector. Existen varias consideraciones para seleccionar el vector más apropiado, incluyendo el potencial de unió;n y entrada a la có;©lula diana, la capacidad de transferencia del material genó;©tico al nó;ºcleo, la habilidad de expresió;n del inserto y la ausencia de toxicidad. En el panorama actual, los vectores virales más utilizados son los derivados de los virus adenoasociados (AAV). Características como su bioseguridad, baja toxicidad y tropismo selectivo, han posibilitado su evaluació;n como opció;n terapó;©utica en un amplio nó;ºmero de enfermedades monogó;©nicas o complejas. A pesar de sus ventajas, los vectores AAV presentan inconvenientes, siendo el más importante la respuesta inmune del paciente al vector, especialmente la respuesta mediada por anticuerpos neutralizantes (NAb). Los NAb disminuyen la transducció;n del vector e impiden la expresió;n del gen que transporta, limitando su aplicació;n clínica. Por lo tanto, identificar y cuantificar la presencia y actividad de los NAbs, es el primer paso en cualquier protocolo de terapia gó;©nica con vectores AAV. La presencia de NAb depende principalmente de la exposició;n al virus en la naturaleza y varía drásticamente segó;ºn edad, localizació;n geográfica y estado de salud de la persona evaluada.

In recent years, gene therapy has been positioned as a real and safe option in the development of therapeutic alternatives for the cure and prevention of different diseases. It consists in the insertion of genetic material in a defective tissue or cell, through the use of a vector. There are several considerations for selecting the most appropriate vector, including the potential for binding and entry to the target cell, the ability of the genetic material to transfer to the nucleus, the ability to express the insert, and the absence of toxicity. In the current scenario, the most commonly used viral vectors are those derived from adeno-associated viruses (AAV). Characteristics such as biosafety, low toxicity and selective tropism have enabled its evaluation as a therapeutic option in many monogenic or complex diseases. Despite their advantages, AAV vectors have drawbacks, the most important being the patient’s immune response to the vector, especially the response mediated by neutralizing antibodies (NAb). NAbs decrease the transduction of the vector and prevent the expression of the gene it transports, limiting its clinical application. Therefore, identifying and quantifying the presence and activity of NAbs is the first step in any gene therapy protocol with AAV vectors. The presence of NAbs depends mainly on exposure to the virus in nature and varies drastically according to age, geographic location and health status of the person evaluated.

Hiposialia y Xerostomía Post Irradiación: Terapias Innovadoras en el Campo Biomolecular / Hyposialia and Xerostomy Post Irradiation: Innovative Therapies in the Biomolecular Field

Las glándulas salivales humanas pueden ser gravemente lesionadas por la radioterapia utilizada contra neoplasias de cabeza y cuello, produciendo hiposialia y xerostomía, las cuales afectan la salud oral y sistémica, mermando la calidad de vida de la persona. Los tratamientos convencionales actuales están diseñados para disminuir los síntomas, sin actuar sobre los cambios fisiopatológicos que se dan a nivel glandular. Esta revisión intenta analizar aquellas terapias preventivas y/o curativas que están desarrollándose en el campo biomolecular y que tienen un futuro prometedor por sus características innovadoras: terapia génica, terapia con células madre y terapia con factores de crecimiento. Se evidencia un aporte adicional de la nanotecnología, la cual está mejorando las vías de aplicación de los tratamientos.

Human salivary glands can be seriously injured by the radiotherapy used against head and neck neoplasms, producing hyposialia and xerostomy, which affect oral and systemic health, diminishing the person's quality of life. Current conventional treatments are designed to reduce symptoms, without acting on the pathophysiological changes that occur at the glandular level. This review attempts to analyze those preventive and /or curative therapies that are developing in the biomolecular field and that have a promising future due to their innovative features: Gene therapy, stem cell therapy and growth factor therapy. An additional contribution of nanotechnology is evident, which is improving the routes of treatment application.

Avances en el tratamiento de la distrofia de Duchenne / Advances in the treatment of Duchenne muscular dystrophy

La distrofia muscular de Duchenne es una enfermedad genéticamente determinada, ligada al cromosoma X y caracterizada clínicamente por producir debilidad muscular progresiva, con una incidencia de 1 por cada 3500-6000 varones nacidos. Es causada por la mutaciones en el gen DMD, el cual codifica la distrofina, una proteína sub-sarcolémica esencial para la estabilidad estructural del músculo. Los defectos genéticos en el gen DMD, se dividen en: deleciones (65%) duplicaciones (5-10%) y mutaciones puntuales (10-15%). Actualmente no se dispone de tratamiento curativo, el único fármaco que ha demostrado modificar la historia natural de la enfermedad (independientemente de la mutación genética) son los corticoides, los cuales están indicados en estadios tempranos de la enfermedad. En relación a los ensayos clínicos, en los últimos diez años se han experimentado grandes avances en el campo de las opciones terapéuticas, divididos en dos grandes dianas terapéuticas: 1) el área de las terapias génicas y 2) tratar de revertir o bloquear los procesos fisiopatológicos de la enfermedad, tales como inflamación, fibrosis, regeneración muscular, etc. Es probable que un tratamiento eficaz para la distrofia muscular de Duchenne requiera combinaciones que se apliquen tanto al defecto primario como las consecuencias fisiopatológicas secundarias.

Duchenne muscular dystrophy is a genetically determined disease, linked to the X chromosome, c haracterized clinically by producing progressive muscle weakness, with an incidence of 1 per 3500-6000 males born. It is caused by the mutation of the DMD gene, which encodes dystrophin, a sub-sarcolemmal protein essential for structural muscle stability. The genetic defects in the DMD gene are divided into: deletions (65%) duplications (5.10%) and point mutations (10-15%). At present there is no curative treatment, the only drug that has been shown to modify the natural history of the disease (independently of the genetic mutation) are corticosteroids, currently indicated in early stages of the disease. In relation to clinical trials, in the last ten years, has experienced great advances in the field of therapeutic options, divided into two major therapeutic targets: 1) the area of gene therapies and 2) trying to reverse or block the pathophysiological processes of the disease, such as inflammation, fibrosis, muscle regeneration, etc. It is likely that an effective treatment for Duchenne muscular dystrophy requires combinations of therapies that address both the primary defect and its secondary pathophysiological consequences.

Neurogenesis and gliogenesis modulation in cerebral ischemia by CDK5 RNAi-based therapy / Modulación de la neurogénesis y la gliogénesis en la isquemia cerebral mediante una terapia basada en la interferencia de CDK5

Abstract Introduction: Cerebral ischemia is the third cause of death risk in Colombia and the first cause of physical disability worldwide. Different studies on the silencing of the cyclin-dependent kinase 5 (CDK5) have shown that reducing its activity is beneficial in ischemic contexts. However, its effect on neural cell production after cerebral ischemia has not been well studied yet. Objective: To evaluate CDK5 silencing on the production of neurons and astrocytes after a focal cerebral ischemia in rats. Materials and methods: We used 40 eight-week-old male Wistar rats. Both sham and ischemia groups were transduced at CA1 hippocampal region with an adeno-associated viral vector using a noninterfering (shSCRmiR) and an interfering sequence for CDK5 (shCDK5miR). We injected 50 mg/kg of bromodeoxyuridine intraperitoneally from hour 24 to day 7 post-ischemia. We assessed the neurological abilities during the next 15 days and we measured the immunoreactivity of bromodeoxyuridine (BrdU), doublecortin (DCX), NeuN, and glial fibrillary acid protein (GFAP) from day 15 to day 30 post-ischemia. Results: Our findings showed that CDK5miR-treated ischemic animals improved their neurological score and presented increased BrdU+ cells 15 days after ischemia, which correlated with higher DCX and lower GFAP fluorescence intensities, and, although mature neurons populations did not change, GFAP immunoreactivity was still significantly reduced at 30 days post-ischemia in comparison with untreated ischemic groups. Conclusion: CDK5miR therapy generated the neurological recovery of ischemic rats associated with the induction of immature neurons proliferation and the reduction of GFAP reactivity at short and longterm post-ischemia.

Resumen Introducción. La isquemia cerebral es la tercera causa de riesgo de muerte en Colombia y la primera causa de discapacidad física en el mundo. En diversos estudios en los que se silenció la cinasa 5 dependiente de la ciclina (CDK5) se ha demostrado que la reducción de su actividad es beneficiosa frente a la isquemia. Sin embargo, su efecto sobre la neurogénesis después de la isquemia no se ha dilucidado suficientemente. Objetivo. Evaluar el silenciamiento de la CDK5 en la neurogénesis y la gliogénesis después de la isquemia cerebral focal en ratas. Materiales y métodos. Se usaron 40 machos de rata Wistar de ocho semanas de edad. Los grupos de control y los isquémicos sometidos a transducción en la región del hipocampo CA1, se inyectaron intraperitonealmente por estereotaxia con 50 mg/kg de bromodesoxiuridina (BrdU) a partir de las 24 horas y hasta el día 7 después de la isquemia, con un vector viral asociado a adenovirus usando una secuencia no interferente (SCRmiR) y una interferente (CDK5miR). Se evaluó la capacidad neurológica durante los quince días siguientes y se detectó la capacidad de inmunorreacción para la BrdU, la proteína doblecortina (DCX), los núcleos neuronales (NeuN), y la proteína fibrilar acídica de la glía (Glial Fibrillary Acidic Protein, GFAP) a los 15 y 30 días de la isquemia. Resultados. Los animales isquémicos tratados con CDK5miR mejoraron su puntuación neurológica y presentaron un incremento de la BrdU+ a los 15 días de la isquemia, lo cual se correlacionó con una mayor intensidad de la DCX+ y una menor de la GFAP+. No hubo modificación de los NeuN+, pero sí una reducción significativa de la GFAP+ a los 30 días de la isquemia en los animales tratados comparados con los animales isquémicos no tratados. Conclusión. La terapia con CDK5miR generó la recuperación neurológica de ratas isquémicas asociada con la inducción de la neurogénesis y el control de la capacidad de reacción de la proteína GFAP a corto y largo plazo después de la isquemia.

Progresos en farmacoterapia en fibrosis quística / Advances in farmacotherapy for cystic fibrosis

Cystic fibrosis is an autosomal recessive multisystemic disease caused by a mutation in the gene encoding the CFTR protein (cystic fibrosis transmembrane conductance regulator). For decades treatments were focused on pulmonary and extrapulmonary symptoms, but in recent years new treatments based on genetics and CFTR mutations have been proposed. The first treatment to appear was genetic therapy, which did not show long-term benefits. These new treatments have allowed a more individualized scheme by using potentiators and modulators of CFTR. Phase III studies and systematic revisions have demonstrated pulmonary function improvement, lower rates of FEV1 decline, reduction in pulmonary exacerbations, BMI improvement and better chloride transport revealed by the sweat test. Recent literature has also shown that these effects persist in the long term.

La Fibrosis Quística es una enfermedad multisistémica autosómica recesiva causada por la mutación del gen que codifica al canal CFTR (proteína de regulación de transmembrana de Fibrosis Quística). Desde hace varias décadas se han utilizado tratamientos enfocados en síntomas pulmonares y extrapulmonares, pero los últimos años han surgido tratamientos basados en genética y mutaciones del CFTR. Inicialmente fue la terapia génica, la cual a largo plazo no demostró beneficios. Las nuevas terapias han permitido un tratamiento individualizado, mediante potenciadores y moduladores del CFTR, demostrándose en estudios fase III y revisiones sistemáticas mejoría en la función pulmonar, disminución de la velocidad de declinación del VEF1, reducción de exacerbaciones pulmonares, mejoría del IMC y del transporte de cloro medido en test del sudor, observándose efectos mantenidos a largo plazo.

Therapeutic advances in 5q-linked spinal muscular atrophy / Avanços terapêuticos na atrofia muscular espinhal ligada ao cromossomo 5q

ABSTRACT Spinal muscular atrophy (SMA) is a severe and clinically-heterogeneous motor neuron disease caused, in most cases, by a homozygous mutation in the SMN1 gene. Regarding the age of onset and motor involvement, at least four distinct clinical phenotypes have been recognized. This clinical variability is, in part, related to the SMN2 copy number. By now, only supportive therapies have been available. However, promising specific therapies are currently being developed based on different mechanisms to increase the level of SMN protein; in particular, intrathecal antisense oligonucleotides that prevent the skipping of exon 7 during SMN2 transcription, and intravenous SMN1 insertion using viral vector. These therapeutic perspectives open a new era in the natural history of the disease. In this review, we intend to discuss the most recent and promising therapeutic strategies, with special consideration to the pathogenesis of the disease and the mechanisms of action of such therapies.

RESUMO A atrofia muscular espinhal (AME) é uma grave doença dos neurônios motores, de grande variabilidade clínica e causada na maioria dos casos por mutação em homozigose no gene SMN1. Pelo menos quatro fenótipos clínicos distintos são reconhecidos com base na idade de início e no grau de envolvimento motor. Tal variabilidade clínica é em parte relacionada com o número de cópias do gene SMN2. Até recentemente, apenas terapias de suporte estavam disponíveis. Atualmente, terapias especificas estão sendo desenvolvidas com base em diferentes mecanismos para aumentar o nível de proteína SMN; em particular oligonucleotídeos antissenso por via intratecal e inserção de cópia do gene SMN1, via endovenosa, usando vetor viral. Nesta revisão, objetivamos discutir as mais recentes e promissoras estratégias terapêuticas, com consideração especial aos aspectos patogênicos da doença e aos mecanismos de ação de tais terapias.

Vascular endothelial growth factor association with angiopoietin 1 promotes improvement in ventricular function after ischemic cardiomyopathy induced in mini pigs

Abstract Purpose: To investigate the safety and clinical, hemodynamic and tissue improvement ability in mini pigs undergoing cell and gene therapy for the treatment of acute myocardial infarction. Methods: Thirty-two mini pigs Br1 lineage, 12 months old, undergoing induction of acute myocardial infarction by occlusion of the diagonal branch of the paraconal coronary. They were divided into 4 groups: one control group and 3 treatment groups (cell therapy and gene cell therapy). Echocardiography reviews were performed on three occasions and histopathological analysis was performed after 4 weeks. Analysis of variance (ANOVA), Tukey and Wilcoxon tests, were performed. Results: Association of vascular endothelial growth factor (VEGF) with angiopoietin1 (Ang1) presented satisfactory results in the improvement of ventricular function following ischemic cardiomyopathy in mini pigs when compared to the results of the other treated groups. Conclusion: The therapy with VEGF and the combination of VEGF with Ang1, promoted recovered function of the myocardium, characterized by reduced akinetic area and induction of neovascularization.

Improving adenoviral vectors and strategies for prostate cancer gene therapy

Gene therapy has been evaluated for the treatment of prostate cancer and includes the application of adenoviral vectors encoding a suicide gene or oncolytic adenoviruses that may be armed with a functional transgene. In parallel, versions of adenoviral vector expressing the p53 gene (Ad-p53) have been tested as treatments for head and neck squamous cell carcinoma and non-small cell lung cancer. Although Ad-p53 gene therapy has yielded some interesting results when applied to prostate cancer, it has not been widely explored, perhaps due to current limitations of the approach. To achieve better functionality, improvements in the gene transfer system and the therapeutic regimen may be required. We have developed adenoviral vectors whose transgene expression is controlled by a p53-responsive promoter, which creates a positive feedback mechanism when used to drive the expression of p53. Together with improvements that permit efficient transduction, this new approach was more effective than the use of traditional versions of Ad-p53 in killing prostate cancer cell lines and inhibiting tumor progression. Even so, gene therapy is not expected to replace traditional chemotherapy but should complement the standard of care. In fact, chemotherapy has been shown to assist in viral transduction and transgene expression. The cooperation between gene therapy and chemotherapy is expected to effectively kill tumor cells while permitting the use of reduced chemotherapy drug concentrations and, thus, lowering side effects. Therefore, the combination of gene therapy and chemotherapy may prove essential for the success of both approaches.

Perspectives for cancer immunotherapy mediated by p19Arf plus interferon-beta gene transfer

While cancer immunotherapy has gained much deserved attention in recent years, many areas regarding the optimization of such modalities remain unexplored, including the development of novel approaches and the strategic combination of therapies that target multiple aspects of the cancer-immunity cycle. Our own work involves the use of gene transfer technology to promote cell death and immune stimulation. Such immunogenic cell death, mediated by the combined transfer of the alternate reading frame (p14ARF in humans and p19Arf in mice) and the interferon-β cDNA in our case, was shown to promote an antitumor immune response in mouse models of melanoma and lung carcinoma. With these encouraging results, we are now setting out on the road toward translational and preclinical development of our novel immunotherapeutic approach. Here, we outline the perspectives and challenges that we face, including the use of human tumor and immune cells to verify the response seen in mouse models and the incorporation of clinically relevant models, such as patient-derived xenografts and spontaneous tumors in animals. In addition, we seek to combine our immunotherapeutic approach with other treatments, such as chemotherapy or checkpoint blockade, with the goal of reducing dosage and increasing efficacy. The success of any translational research requires the cooperation of a multidisciplinary team of professionals involved in laboratory and clinical research, a relationship that is fostered at the Cancer Institute of Sao Paulo.

Lysozyme gene treatment in testosterone induced benign prostate hyperplasia rat model and comparasion of its' effectiveness with botulinum toxin injection

ABSTRACT Objectives: To compare the effects and histopathological changes of botulinum neurotoxin type A and lysozyme gene injections into prostate tissue within a testosterone induced benign prostate hyperplasia rat model. Materials and Methods: 40 male Wistar rats were randomized into four Groups. Group-1: Control, Group-2: Testosterone replacement, Group-3: Testosterone+botulinum neurotoxin type A, Group-4: Testosterone+plazmid DNA/liposome complex. Results: Estimated prostate volume of the testosterone injected Groups were higher than the control (p <0.05). Actual prostate weight of the testosterone injected Groups was higher than the control Group (p <0.05). Testosterone undecanoate increased the prostate weight by 39%. Botulinum neurotoxin type A treatment led to an estimated prostate volume and actual prostate weights decreased up to 32.5% in rats leading to prostate apoptosis. Lysozyme gene treatment led to an estimated prostate volume and actual prostate weights decrease up to 38.7%. Conclusion: Lysozyme gene and botulinum neurotoxin type A treatments for prostate volume decreasing effect have been verified in the present study that could be anew modality of treatment in prostatic benign hyperplasia that needs to be verified in large randomized human experimental studies.

Gene therapy: advances, challenges and perspectives / Terapia gênica: avanços, desafios e perspectivas

ABSTRACT The ability to make site-specific modifications to the human genome has been an objective in medicine since the recognition of the gene as the basic unit of heredity. Thus, gene therapy is understood as the ability of genetic improvement through the correction of altered (mutated) genes or site-specific modifications that target therapeutic treatment. This therapy became possible through the advances of genetics and bioengineering that enabled manipulating vectors for delivery of extrachromosomal material to target cells. One of the main focuses of this technique is the optimization of delivery vehicles (vectors) that are mostly plasmids, nanostructured or viruses. The viruses are more often investigated due to their excellence of invading cells and inserting their genetic material. However, there is great concern regarding exacerbated immune responses and genome manipulation, especially in germ line cells. In vivo studies in in somatic cell showed satisfactory results with approved protocols in clinical trials. These trials have been conducted in the United States, Europe, Australia and China. Recent biotechnological advances, such as induced pluripotent stem cells in patients with liver diseases, chimeric antigen receptor T-cell immunotherapy, and genomic editing by CRISPR/Cas9, are addressed in this review.

RESUMO A habilidade de fazer modificações pontuais no genoma humano tem sido o objetivo da medicina desde o conhecimento do DNA como unidade básica da hereditariedade. Entende-se terapia gênica como a capacidade do melhoramento genético por meio da correção de genes alterados (mutados) ou modificações sítio-específicas, que tenham como alvo o tratamento terapêutico. Este tipo de procedimento tornou-se possível por conta dos avanços da genética e da bioengenharia, que permitiram a manipulação de vetores para a entrega do material extracromossomal em células-alvo. Um dos principais focos desta técnica é a otimização dos veículos de entrega (vetores) que, em sua maioria, são plasmídeos, nanoestruturados ou vírus − sendo estes últimos os mais estudados, devido à sua excelência em invadir as células e inserir seu material genético. No entanto, existe grande preocupação referente às respostas imunes exacerbadas e à manipulação do genoma, principalmente em linhagens germinativas. Estudos em células somáticas in vivo apresentaram resultados satisfatórios, e já existem protocolos aprovados para uso clínico. Os principais trials têm sido conduzidos nos Estados Unidos, Europa, Austrália e China. Recentes avanços biotecnológicos empregados para o aprimoramento da terapia gênica, como células-tronco pluripotentes induzidas em pacientes portadores de doenças hepáticas, imunoterapia com células T do receptor do antígeno quimera e edição genômica pelos sistema CRISPR/Cas9, são abordados nesta revisão.

Immunotherapy and gene therapy as novel treatments for cancer / Inmunoterapia y terapia génica como nuevos tratamientos contra el cáncer

Abstract The immune system interacts closely with tumors during the disease development and progression to metastasis. The complex communication between the immune system and the tumor cells can prevent or promote tumor growth. New therapeutic approaches harnessing protective immunological mechanisms have recently shown very promising results. This is performed by blocking inhibitory signals or by activating immunological effector cells directly. Immune checkpoint blockade with monoclonal antibodies directed against the inhibitory immune receptors CTLA-4 and PD-1 has emerged as a successful treatment approach for patients with advanced melanoma. Ipilimumab is an anti-CTLA-4 antibody which demonstrated good results when administered to patients with melanoma. Gene therapy has also shown promising results in clinical trials. Particularly, Herpes simplex virus (HSV)-mediated delivery of the HSV thymidine kinase (TK) gene to tumor cells in combination with ganciclovir (GCV) may provide an effective suicide gene therapy for destruction of glioblastomas, prostate tumors and other neoplasias by recruiting tumor-infiltrating lymphocytes into the tumor. The development of new treatment strategies or combination of available innovative therapies to improve cell cytotoxic T lymphocytes trafficking into the tumor mass and the production of inhibitory molecules blocking tumor tissue immune-tolerance are crucial to improve the efficacy of cancer therapy.

Resumen El sistema inmune interactúa íntimamente con los tumores durante el proceso del desarrollo de la enfermedad y su progresión a metástasis. Esta compleja comunicación entre el sistema inmune y las células tumorales puede prevenir o promover el crecimiento del tumor. Los nuevos enfoques terapéuticos que aprovechan los mecanismos inmunológicos, ya sea por el bloqueo de señales inhibitorias o por la activación directa de células efectoras, han mostrado resultados prometedores. El bloqueo de puntos de control inmunológicos (immune-checkpoints) con anticuerpos monoclonales dirigidos contra receptores que normalmente inhiben el sistema inmune, como CTLA-4 o PD-1, ha resultado ser un tratamiento exitoso para pacientes con melanoma avanzado. El fármaco ipilimumab es un anticuerpo anti-CTLA-4 que ha demostrado buenos resultados terapéuticos en pacientes con melanoma. Por otro lado, la terapia génica también ha mostrado resultados prometedores en ensayos clínicos. En especial, la administración de la enzima timidina quinasa del virus Herpes simplex (HSV-TK) en combinación con el fármaco ganciclovir (GCV) ha mostrado ser una terapia suicida muy efectiva para la destrucción de diferentes neoplasias incluyendo glioblastomas y tumores prostáticos, por un mecanismo que involucra el reclutamiento de linfocitos infiltrantes de tumor. Es importante la búsqueda de nuevas estrategias o la combinación de terapias innovadoras, con el fin de involucrar tanto la atracción de linfocitos citotóxicos así como el empleo de moléculas que inhiban la inmunotolerancia del tejido tumoral para mejorar la eficiencia de los tratamientos contra el cáncer.

Long-term restoration of alpha-L-iduronidase activity in fibroblasts from patients with mucopolysaccharidosis type I after non-viral gene transfer

Mucopolysaccharidosis type I (MPS I) is a lysosomal storage disorder caused by deficiency of alpha-L-iduronidase (IDUA). Limitations such as the need for weekly injections, high morbidity and mortality, and high cost of current treatments show that new approaches to treat this disease are required. In this study, we aimed to correct fibroblasts from a patient with MPS I using non-viral gene therapy. Using a plasmid encoding the human IDUA cDNA, we achieved stable high IDUA levels in transfected fibroblasts up to 6 months of treatment. These results serve as proof of concept that a non-viral approach can correct the enzyme deficiency in cells of patients with lysosomal storage disorders, which can be used as a research tool for a series of disease aspects. Future studies should focus on showing if this approach can be useful in small animals and clinical trials (AU)

Nivel de autoconcepto en niños con secuelas de quemaduras: estudio comparativo / Self-concept level in children with burns sequelae: A comparative study

Introducción: Autoconcepto es el conjunto de ideas y actitudes que se tiene acerca de sí mismo. Nuestro objetivo fue evaluar si existen diferencias en el nivel de autoconcepto de niños de 8-12 años con y sin secuelas de quemaduras, e identificar variables predictoras del autoconcepto en los niños con secuelas. Pacientes y método: Estudio comparativo, transversal de 109 niños con secuelas de quemaduras de 8 a 12 años de edad, con 109 niños sin secuelas de quemaduras, del mismo grupo de edad y nivel socioeconómico. Se utilizó la escala de autoconcepto de Piers-Harris, que entrega medida de autoconcepto general y dimensiones: conductual, estatus intelectual y escolar, apariencia y atributos físicos, ansiedad, popularidad, felicidad y satisfacción. Resultados: No hubo diferencias significativas en el nivel de autoconcepto general ni en sus dimensiones al comparar ambos grupos (p > 0,05). Dentro del grupo con secuelas de quemaduras la variable número de secuelas resultó ser un factor protector para las dimensiones ansiedad, popularidad, felicidad-satisfacción y autoconcepto general. La variable localización surgió como factor de riesgo para la dimensión conductual. Discusión: La ausencia de diferencias en autoconcepto entre niños con secuelas de quemaduras y sin ellas es similar a lo reportado por la literatura. El hallazgo en factores de riesgo y protectores motiva a continuar investigando, incorporando antecedentes premórbidos y familiares.

Introduction: Self-concept is the set of ideas and attitudes that a person has about him/herself. Objective: To evaluate whether there are differences in the level of self-concept in children 8-12 years old with and without burns sequelae. To identify predictive variables of self-concept in children with sequelae. Patients and method: A comparative cross-sectional study of self-concept in 109 children with burns sequelae, from 8 to 12 years old, with 109 children without burns sequelae, and of the same age and socioeconomic status. The Piers-Harris self-concept scale is used, which provides a general measurement of self-concept and behavioural, intellectual and school status, appearance, and physical attributes, anxiety, popularity, happiness and satisfaction dimensions. Results: There were no significant differences in the level of general self-concept or their dimensions (P > .05). In the group with burns sequelae, the protective factor was the variable number of sequels was associated with the dimensions of anxiety, popularity, happiness-satisfaction and general self-concept. The location variable emerged as a risk factor for the behavioural dimension. Discussion: The absence of differences in self-concept between children with burns sequelae and children without them is similar to that reported in the literature. The finding in the risk and protective factors encourages to further research, and perhaps incorporating pre-morbidity and family background.

Cells involved in extracellular matrix remodeling after acute myocardial infarction / Células envolvidas no remodelamento da matriz extracelular após infarto agudo do miocárdio

Objective Evaluate the effects of VEGF165 gene transfer in the process of remodeling of the extracellular matrix after an acute myocardial infarct. Methods Wistar rats were submitted to myocardial infarction, after the ligation of the left descending artery, and the left ventricle ejection fraction was used to classify the infarcts into large and small. The animals were divided into groups of ten, according to the size of infarcted area (large or small), and received or not VEGF165 treatment. Evaluation of different markers was performed using immunohistochemistry and digital quantification. The primary antibodies used in the analysis were anti-fibronectin, anti-vimentin, anti-CD44, anti-E-cadherin, anti-CD24, anti-alpha-1-actin, and anti-PCNA. The results were expressed as mean and standard error, and analyzed by ANOVA, considering statistically significant if p≤0.05. Results There was a significant increase in the expression of undifferentiated cell markers, such as fibronectin (protein present in the extracellular matrix) and CD44 (glycoprotein present in the endothelial cells). However, there was decreased expression of vimentin and PCNA, indicating a possible decrease in the process of cell proliferation after treatment with VEGF165. Markers of differentiated cells, E-cadherin (adhesion protein between myocardial cells), CD24 (protein present in the blood vessels), and alpha-1-actin (specific myocyte marker), showed higher expression in the groups submitted to gene therapy, compared to non-treated group. The value obtained by the relation between alpha-1-actin and vimentin was approximately three times higher in the groups treated with VEGF165, suggesting greater tissue differentiation. Conclusion The results demonstrated the important role of myocytes in the process of tissue remodeling, confirming that VEGF165 seems to provide a protective effect in the treatment of acute myocardial infarct. .

Objetivo Avaliar os efeitos da transferência gênica do VEGF165 no processo de remodelamento da matriz extracelular após infarto agudo do miocárdio. Métodos Ratos Wistar foram submetidos ao infarto do miocárdio por ligação da artéria coronária descendente esquerda, e a fração de ejeção de ventrículo esquerdo foi utilizada para classificar os infartos em grandes e pequenos. Os animais foram divididos em grupos de dez animais, de acordo com o tamanho do infarto (grande ou pequeno), e receberam ou não tratamento com o VEGF165. A avaliação dos diferentes marcadores foi realizada por imuno-histoquímica e quantificação digital. Os anticorpos primários utilizados foram antifibronectina, antivimentina, anti- CD44, anti-E-caderina, anti-CD24, anti-alfa-1-actina e anti-PCNA. Os resultados foram representados como média e erro padrão, e analisados por ANOVA, sendo considerado estatisticamente significativo se p≤0,05. Resultados Houve aumento significativo da expressão de marcadores de células indiferenciadas, como fibronectina (proteína presente na matriz extracelular) e CD44 (glicoproteína presente nas células endoteliais). Entretanto, houve diminuição da expressão de vimentina e PCNA, indicando possível diminuição do processo de proliferação celular após o tratamento com VEGF165. Os marcadores de células diferenciadas, E-caderina (proteína de adesão entre as células do miocárdio), CD24 (proteína presente nos vasos sanguíneos) e alfa-1-actina (marcador especifico de miócitos) também apresentaram maior expressão nos grupos submetidos à terapia gênica, comparativamente com o grupo não tratado. O valor obtido pela relação entre alfa-1-actina e vimentina foi aproximadamente três vezes maior nos grupos tratados com VEGF165, indicando maior diferenciação tecidual. Conclusão O papel dos miócitos se mostrou importante no processo de remodelamento tecidual, confirmando que o VEGF165 parece conferir um efeito protetor no tratamento do infarto agudo do miocárdio. .