Opportunities and Challenges of RNA Interference Therapeutics in Oncology / 中国肺癌杂志

As the discovery of RNA interference (RNAi) and the gradual conquering of a series of technical issues, a few of RNAi therapeutics have been approved in the non-tumor field abroad. With the advantages of high specificity, long duration of efficacy, and high success rate of development, RNAi therapeutics have become the emerging field globally. There are no RNAi therapeutics approved in oncology so far, and people are hoping a breakthrough in the field. In the present article, the characteristics and potential anti-tumor mechanism of RNAi therapeutics, difficulties in delivery system and progress in oncology are described, and the potential reasons why their success in non-tumor field is difficult to be simply replicated in tumor field are analyzed, providing reference for research and clinical transformation of RNAi therapeutics in oncology.
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Potencial uso terapéutico del ARN de interferencia contra la COVID-19 / Potential therapeutic use of RNA interference against COVID-19

Introducción: El SARS-CoV-2 es el agente causal de la COVID-19, enfermedad respiratoria que ha causado miles de víctimas fatales a escala global, y para la cual no existe ninguna terapia curativa efectiva. Objetivo: Reflejar la relevancia potencial de la tecnología de ARN de interferencia (ARNi), como alternativa terapéutica contra la COVID-19. Material y métodos: Se consultaron las bases de datos especializadas en busca de artículos publicados hasta abril de 2020. Se emplearon descriptores específicos y operadores booleanos. Se empleó la estrategia de búsqueda avanzada para la selección de los artículos, teniendo en cuenta la calidad metodológica o validez de los estudios. Desarrollo: Fueron identificadas evidencias de aplicación a nivel experimental de la tecnología de ARNi contra el SARS-CoV. Se han diseñado y evaluado varios ARNs pequeños interferentes y ARNs pequeños con estructura en lazo, orientados al silenciamiento de genes esenciales del SARS-CoV, incluyendo aquellos que codifican las proteínas S, RdRp, M, E, N, 3a/3b y 7a/7b. Se comprobó la efectividad de los ARNi en el silenciamiento de sus genes diana. Aunque la mayoría de estas investigaciones se han realizado en sistemas in vitro, también se ha comprobado la utilidad terapéutica de la administración intranasal de ARNi en un modelo de SARS-CoV in vivo. Conclusiones: La tecnología de ARNi ha mostrado potencialidades como estrategia terapéutica contra el SARS-CoV en modelos celulares y animales. Dadas las similitudes a nivel genómico y en cuanto al proceso patogénico entre SARS-CoV y SARS-CoV-2, esta tecnología es potencialmente aplicable el tratamiento de la COVID-19(AU)

Introduction: SARS-CoV-2 is the causal agent of COVID-19, a respiratory disease that has caused thousands of deaths globally for which there is no effective curative therapy. Objective: To demonstrate the potential relevance of RNA interference (RNAi) technology as a therapeutic alternative in the treatment of COVID-19. Materials and methods: Specialized biomedical databases were searched looking for studies published until April 2020. The search was carried out using descriptors and Boolean operators. Advanced search strategy was used for the selection of articles, taking into account the methodological quality and validity of the studies. Results: Evidence of experimental application of RNAi technology against SARS-CoV was identified. Several small interfering RNAs and small loop-structured RNAs oriented to the silencing of essential SARS-CoV genes including those encoding the S, RdRp, M, E, N, 3a/3b and 7a/7b proteins have been designed and evaluated. The effectiveness of RNAi for silencing its target genes was proven. Although most of these research studies have been conducted in in vitro systems, the therapeutic effectiveness of the intranasal administration of small RNA interference has also been proven in an in vivo SARS-CoV model. Conclusions: RNAi technology has demonstrated to be a potential therapeutic strategy against SARS-CoV in cellular and animal models. Given the similarities at the genomic level and in terms of the pathogenic process between SARS-CoV and SARS-CoV-2, this technology has a potential applicability for the treatment of COVID-19(AU)

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.

Brazilian consensus for diagnosis, management and treatment of transthyretin familial amyloid polyneuropathy / Consenso Brasileiro para o diagnóstico, manejo e tratamento da Polineuropatia Amiloidótica Familiar associada à Transtirretina

ABSTRACT Transthyretin familial amyloid polyneuropathy is an autosomal dominant inherited sensorimotor and autonomic polyneuropathy, which if untreated, leads to death in approximately 10 years. In Brazil, liver transplant and tafamidis are the only disease-modifying treatments available. This review consists of a consensus for the diagnosis, management and treatment for transthyretin familial amyloid polyneuropathy from the Peripheral Neuropathy Scientific Department of the Brazilian Academy of Neurology. The first and last authors produced a draft summarizing the main views on the subject and emailed the text to 10 other specialists. Relevant literature on this subject was reviewed by each participant and used for the individual review of the whole text. Each participant was expected to review the text and send a feedback review by e-mail. Thereafter, the 12 panelists got together at the city of Fortaleza, discussed the controversial points, and reached a consensus for the final text.

RESUMO Polineuropatia amiloidótica familiar é uma polineuropatia sensitivo-motora e autonômica de herança autossômica dominante, que caso não seja tratada leva a morte em aproximadamente 10 anos. O transplante de fígado e o tafamidis são os únicos tratamentos disponíveis no Brasil. Essa revisão consiste em um consenso do Departamento Científico de Neuropatias Periféricas da Academia Brasileira de Neurologia. O primeiro e último autores produziram um texto resumindo os principais aspectos sobre o tema e enviaram para os outros 10 especialistas por email. A literatura relevante sobre o assunto foi revisada por cada participante e utilizada para revisão individual do texto. Foi esperado que cada participante revisasse o texto e enviasse suas sugestões por e-mail. Finalmente, os 12 panelistas se encontraram na cidade de Fortaleza para discutir os pontos controversos e chegar a um consenso sobre texto final.

Developments in the use of nanocapsules in oncology

The application of nanotechnology to medicine can provide important benefits, especially in oncology, a fact that has resulted in the emergence of a new field called Nanooncology. Nanoparticles can be engineered to incorporate a wide variety of chemotherapeutic or diagnostic agents. A nanocapsule is a vesicular system that exhibits a typical core-shell structure in which active molecules are confined to a reservoir or within a cavity that is surrounded by a polymer membrane or coating. Delivery systems based on nanocapsules are usually transported to a targeted tumor site and then release their contents upon change in environmental conditions. An effective delivery of the therapeutic agent to the tumor site and to the infiltrating tumor cells is difficult to achieve in many cancer treatments. Therefore, new devices are being developed to facilitate intratumoral distribution, to protect the active agent from premature degradation and to allow its sustained and controlled release. This review focuses on recent studies on the use of nanocapsules for cancer therapy and diagnosis.

The effect of down-regulation of Smad3 by RNAi on hepatic stellate cells and a carbon tetrachloride-induced rat model of hepatic fibrosis

Searching for effective Smad3 gene-based gene therapies for hepatic fibrosis, we constructed siRNA expression plasmids targeting the rat Smad3 gene and then delivered these plasmids into hepatic stellate cells (HSCs). The effect of siRNAs on the mRNA levels of Smad2, Smad3, Smad4, and collagens I-α1, III-α1 and IV-α1 (Colα1, Col3α1, Col4α1, respectively) was determined by RT-PCR. Eighty adult male Sprague-Dawley rats were randomly divided into three groups. Twice a week for 8 weeks, the untreated hepatic fibrosis model (N = 30) and the treated group (N = 20) were injected subcutaneously with 40 percent (v/v) carbon tetrachloride (CCl4)-olive oil (3 mL/kg), and the normal control group (N = 30) was injected with olive oil (3 mL/kg). In the 4th week, the treated rats were injected subcutaneously with liposome-encapsulated plasmids (150 µg/kg) into the right liver lobe under general anesthesia once every 2 weeks, and the untreated rats were injected with the same volume of buffer. At the end of the 6th and 8th weeks, liver tissue and sera were collected. Pathological changes were assessed by a semi-quantitative scoring system (SSS), and a radioimmunoassay was used to establish a serum liver fibrosis index (type III procollagen, type IV collagen, laminin, and hyaluronic acid). The mRNA expression levels of the above cited genes were reduced in the HSCs transfected with the siRNA expression plasmids. Moreover, in the treated group, fibrosis evaluated by the SSS was significantly reduced (P < 0.05) and the serum indices were greatly improved (P < 0.01). These results suggest that Smad3 siRNA expression plasmids have an anti-fibrotic effect.

Intravenous KITENIN shRNA Injection Suppresses Hepatic Metastasis and Recurrence of Colon Cancer in an Orthotopic Mouse Model

KITENIN (KAI1 C-terminal interacting tetraspanin) promotes invasion and metastasis in mouse colon cancer models. In the present study, we evaluated the effects of KITENIN knockdown by intravenous administration of short hairpin RNAs (shRNAs) in an orthotopic mouse colon cancer model, simulating a primary or adjuvant treatment setting. We established orthotopic models for colon cancer using BALB/c mice and firefly luciferase-expressing CT-26 (CT26/Fluc) cells. Tumor progression and response to therapy were monitored by bioluminescence imaging (BLI). In the primary therapy model, treatment with KITENIN shRNA substantially delayed tumor growth (P = 0.028) and reduced the incidence of hepatic metastasis (P = 0.046). In the adjuvant therapy model, KITENIN shRNA significantly reduced the extent of tumor recurrence (P = 0.044). Mice treated with KITENIN shRNA showed a better survival tendency than the control mice (P = 0.074). Our results suggest that shRNA targeting KITENIN has the potential to be an effective tool for the treatment of colon cancer in both adjuvant and metastatic setting.

Nuevos horizontes en el tratamiento de las callosidades plantares de la paquioniquia congénita / New horizons in the treatment of plantar callosities congenital pachyonychia

Los avances recientes en el campo de la terapia génica, tales como el desarrollo de ARN de cadena corta inhibitorios (ARNsi) capaces de silenciar la expresión de alelos mutados dominantes, ofrecen nuevas expectativas para el tratamiento de la queratodermia plantar en pacientes con paquioniquia congénita. Revisamos brevemente las características clínicas de esta entidad y describimos un estudio de fase 1 que arrojó resultados prometedores. Los mismos serían aplicables a todo el campo de las enfermedades monogénicas.

Recent advances in the genetic therapy field like development of short inhibitory RNA (RNAsi) capable of silencing mutant dominant alleles, offer new expectations for treatment of plantar keratoderma in patients with pachyonichya congenita. We briefly review clinical features of this entity and describe a fase 1 study that showed promising results that may be usefull for the whole monogenic diseases field.

Short-interfering RNAs as antivirals against rabies

This study aimed to test in vitro a RNA-interference based antiviral approach for rabies with short-interfering RNAs (siRNAs) against rabies virus nucleoprotein mRNA. BHK-21 cells were infected with serial dilutions of PV rabies virus strain and transfected with a pool of three siRNAs. Direct immunofluorescence staining showed a 5-time decrease in virus titer when compared to a non-treated plate, showing a promising new approach to the development of antivirals for rabies treatment.