MicroRNA-153-3p enhances cell radiosensitivity by targeting BCL2 in human glioma

BACKGROUND: Glioma is the most prevalent malignant tumor in human central nervous systems. Recently, the development of resistance to radiotherapy in glioma patients markedly vitiates the therapy outcome. MiR-153-3p has been reported to be closely correlated with tumor progression, but its effect and molecular mechanism underlying radioresistance remains unclear in glioma. METHODS: The expression of miR-153-3p was determined in radioresistant glioma clinical specimens as well as glioma cell lines exposed to irradiation (IR) using quantitative real-time PCR. Cell viability, proliferation and apoptosis were then evaluated by MTT assay, colony formation assay, Flow cytometry analysis and caspase-3 activity assay in glioma cells (U87 and U251). Tumor forming was evaluated by nude mice model in vivo. TUNEL staining was used to detect cell apoptosis in nude mice model. The target genes of miR-153-3p were predicted and validated using integrated bioinformatics analysis and a luciferase reporter assay. RESULTS: Here, we found that miR-153-3p was down-regulated in radioresistant glioma clinical specimens as well as glioma cell lines (U87 and U251) exposed to IR. Enhanced expression of miR-153-3p promoted the radiosensitivity, promoted apoptosis and elevated caspase-3 activity in glioma cells in vitro, as well as the radiosensitivity in U251 cell mouse xenografs in vivo. Mechanically, B cell lymphoma-2 gene (BCL2) was identified as the direct and functional target of miR-153-3p. Moreover, restoration of BCL2 expression reversed miR-153-3p-induced increase of radiosensitivity, apoptosis and caspase-3 activity in U251 cells in vitro. In addition, clinical data indicated that the expression of miR-153-3p was significantly negatively associated with BCL2 in radioresistance of glioma samples. CONCLUSIONS: Our findings suggest that miR-153-3p is a potential target to enhance the effect of radiosensitivity on glioma cells, thus representing a new potential therapeutic target for glioma.

The search for novel insecticide targets in the post-genomics era, with a specific focus on G-protein coupled receptors

Insects are considered pests globally, implicated in the destruction of agricultural fields and transmission of pathogens that cause deadly human diseases, such as dengue, Zika and malaria. The diversity of the insecticide arsenal has remained stagnant for decades, but the recent rise of insecticide resistance fueled the discovery of novel modes of action, and the power of genomics has reinvigorated this search. This review discusses the importance of comparative and functional insect genomics in the identification of potential gene targets for an insecticidal mode of action with low off-target toxicity. Due to the global participation in the sequencing and annotation of insect genomes, the targeting of specific genes with molecular tools like RNAi and CRISPR/Cas9 for genome engineering and consequent functional identification and validation has become more efficient. While there are multiple avenues to explore for insecticidal candidates, this review identifies G-protein coupled receptors as attractive targets, and hones in on the octopamine and dopamine receptors due to their potential.

Identification of therapeutic target genes with DNA microarray in multiple myeloma cell line treated by IKKβ/NF-κB inhibitor

PURPOSE: To explore the mechanism of resistance to IKKβ inhibitor in multiple myeloma (MM) cells and uncover novel therapeutic targets for MM. METHODS: We downloaded the microarray data (GSE8476) from GEO (Gene Expression Omnibus) database. The data were derived from the human MM cells lines (L363 cells) treated with IKKβ inhibitor MLN120b (MLN) for eight, 12 and 24 hours. Furthermore, we applied the Search Tool for the Retrieval of Interacting Genes (STRING) and Expression Analysis Systematic Explorer (EASE) database to construct protein-protein interaction networks and identified over-represented pathway among DEGs (differentially expressed genes). RESULTS: We obtained 108 DGEs in 8h vs. 12h group and 101 ones in 8h vs. 24h group. Most of DGEs were found to be involved in biological regulation. The significant pathways were Ig A pathway and the CAMs pathways. In addition, 24 common DGEs were found in the networks of the two groups such as ICAM 3 and SELL. CONCLUSION: Intercellular adhesion molecule 3 and SELL may be potential targets in multiple myeloma treatment in the future. .

The use of biodiversity as source of new chemical entities against defined molecular targets for treatment of malaria, tuberculosis, and T-cell mediated diseases: a review

The modern approach to the development of new chemical entities against complex diseases, especially the neglected endemic diseases such as tuberculosis and malaria, is based on the use of defined molecular targets. Among the advantages, this approach allows (i) the search and identification of lead compounds with defined molecular mechanisms against a defined target (e.g. enzymes from defined pathways), (ii) the analysis of a great number of compounds with a favorable cost/benefit ratio, (iii) the development even in the initial stages of compounds with selective toxicity (the fundamental principle of chemotherapy), (iv) the evaluation of plant extracts as well as of pure substances. The current use of such technology, unfortunately, is concentrated in developed countries, especially in the big pharma. This fact contributes in a significant way to hamper the development of innovative new compounds to treat neglected diseases. The large biodiversity within the territory of Brazil puts the country in a strategic position to develop the rational and sustained exploration of new metabolites of therapeutic value. The extension of the country covers a wide range of climates, soil types, and altitudes, providing a unique set of selective pressures for the adaptation of plant life in these scenarios. Chemical diversity is also driven by these forces, in an attempt to best fit the plant communities to the particular abiotic stresses, fauna, and microbes that co-exist with them. Certain areas of vegetation (Amazonian Forest, Atlantic Forest, Araucaria Forest, Cerrado-Brazilian Savanna, and Caatinga) are rich in species and types of environments to be used to search for natural compounds active against tuberculosis, malaria, and chronic-degenerative diseases. The present review describes some strategies to search for natural compounds, whose choice can be based on ethnobotanical and chemotaxonomical studies, and screen for their ability to bind to immobilized drug targets and to inhibit their activities. Molecular cloning, gene knockout, protein expression and purification, N-terminal sequencing, and mass spectrometry are the methods of choice to provide homogeneous drug targets for immobilization by optimized chemical reactions...

Stable genetic transformation of malaria parasites by homologous recombination

A transformaçäo genética de diferentes estágios dos parasitas da malária já é possível atualmente. Um conjunto crescente de marcadores seletivos estäo sendo desenvolvidos para permitir uma manipulaçäo genética mais completa de Plasmodium. "Gene targeting", que permite romper um gene ou introduzir alterações sutis na seqüência de um gene via recombinaçäo homóloga, é uma nova tecnologia usada no estudo de estrutura-funçäo de antígenos in vivo. A criaçäo de parasitas recombinantes carreando mutações pontuais em sítios conservados de TRAP de esporozoitas de P. berghei é usado como protótipo desta nova tecnologia.

Evaluación de métodos de marcación radioactivos y no radioactivos en la elaboración de sondas diagnósticas de malaria / Evaluation of radioactive and non radiactive labelling methods in the elaboration of malaria diagnostic probes

El diagnóstico eficiente y rápido es el primer paso importante en el control epidemiológico de la malaria. Es por esto que se ha sugerido la necesidad de explorar nuevos procedimientos de detección, que superen las limitaciones presentadas por el examen microscópico empleado para tal fín. Por esta razón, en este trabajo se evaluaron métodos de marcación radioactivos y no radioactivos, empleados en la producción de sondas para el diagnóstico a nivel epidemiológico de P. falciparum y P. vivax. Se evaluaron además las condiciones óptimas de hibridización, la preparación de las muestras y las sondas utilizadas. Dentro de los métodos de marcación radioactivos probados, la reacción Random Primers, resultó mejor que Nick Translation, obteniéndose mejores incorporaciones de [a superíndice 35 S]dATP, resultando en sondas con mayor actividad específica (1-2X10 superíndice 9). Se logró un sensibilidad 10 veces mayor en la detección de ADN de P. falciparum, empleando el sistema Random Primers, con respecto a la obtenida con Nick Translation, y de esta forma se alcanzaron los niveles reportados en la literatura. La sensibilidad alcanzada (12 pg), se logró tanto con la sonda p38R desarrollada y caracterizada en nuestro laboratorio, como con la sonda pRepHind, una de las más utilizadas en los laboratorios de otros paises, aumentando el interés en conocer más a fondo el clon p38R. El método de marcación no radioactivo con Fotobiotina, mostró ventajas sobre la marcación con Biotina, y se alcanzó la misma sensibilidad de 135 pg de ADN de P. falciparum. Utilizando los oligonucléotidos 21mer y 25mer para detectar P. falciparum y P. vivax respectivamente, maracados con Terminal Transferasa, en nuestros experimentos no resultaron buenas sondas de diagnóstico. También se probó como método de detección no radioactivo, el sistema de generación de señales fluorescentes, mediante el empleo de proteasas, logrando en un ensayo preliminar de sensibilidad detectar 13 pg de P. falciparum. Aunque este sistema tiene problemas de señales inespecíficas que deben solucionarse, los resultados preliminares muestran sus posibilidades como método de detección