m7G-lncRNAs are potential biomarkers for prognosis and tumor microenvironment in patients with colon cancer / 南方医科大学学报

OBJECTIVE@#To assess the value of m7G-lncRNAs in predicting the prognosis and microenvironment of colorectal cancer (CRC).@*METHODS@#We screened m7G-lncRNAs from TCGA to construct an m7G-lncRNAs risk model using multivariate Cox analysis, which was validated using ROC and C-index curves. Calibration and nomogram were used to predict the prognosis of CRC patients. Point-bar charts and K-M survival curves were used to assess the correlation of risk scores with the patients' clinical staging and prognosis. CIBERSORT and ESTIMATE were used to explore the association between the tumor microenvironment and immune cell infiltration in patients in high and low risk groups and the correlation of risk scores with microsatellite instability, stem cell index and immune checkpoint expression. A protein-protein interaction network was constructed, and the key targets regulated by m7G-lncRNAs were identified and validated in paired samples of CRC and adjacent tissues by immunoblotting.@*RESULTS@#We identified a total of 1722 m7G-lncRNAs from TCGA database, from which 12 lncRNAs were screened to construct the risk model. The AUCs of the risk model for predicting survival outcomes at 1, 3 and 5 years were 0.727, 0.747 and 0.794, respectively. The AUC of the nomogram for predicting prognosis was 0.794, and the predicted results were consistent with actual survival outcomes of the patients. The patients in the high-risk group showed more advanced tumor stages and a greater likelihood of high microsatellite instability than those in the low-risk group (P < 0.05). The tumor stemness index was negatively correlated with the risk score (r=-0.19; P=7.3e-05). Patients in the high-risk group had higher stromal cell scores (P=0.0028) and higher total scores (P=0.007) with lowered expressions of activated mast cells (r=-0.11; P=0.045) and resting CD4+ T cells (r=-0.14; P=0.01) and increased expressions of most immune checkpoints (P < 0.05). ATXN2 (P= 0.006) and G3BP1 (P=0.007) were identified as the key targets regulated by m7G-lncRNAs, and their expressions were both higher in CRC than in adjacent tissues.@*CONCLUSION@#The risk model based on 12 m7G-lncRNAs has important prognostic value for CRC and can reflect the microenvironment and the efficacy of immunotherapy in the patients.

Anticuerpos policlonales contra la proteína recombinante NS3 del virus del dengue / Polyclonal antibodies against recombinant dengue virus NS3 protein

Resumen Introducción: El dengue es una enfermedad causada por uno de los cuatro serotipos del virus del dengue (DENV) y es endémica en, aproximadamente, 130 países. Su incidencia ha aumentado notablemente en las últimas décadas, así como la frecuencia y la magnitud de los brotes. A pesar de los esfuerzos, no existen tratamientos profilácticos ni terapéuticos contra la enfermedad y, en ese contexto, el estudio de los procesos que gobiernan el ciclo de infección del DENV es esencial para desarrollar vacunas o terapias antivirales. Una de las moléculas del DENV más prometedoras es la proteína no estructural 3 (NS3), la cual es indispensable para la replicación viral y es uno de los principales blancos inmunológicos durante la infección. Objetivo: Producir anticuerpos policlonales para contribuir a los futuros estudios sobre las interacciones entre la proteína NS3 y otras proteínas celulares. Materiales y métodos: Se expresaron dos proteínas recombinantes del dominio helicasa de NS3 del DENV de serotipo 2, las cuales se emplearon para inmunizar ratas y producir anticuerpos policlonales. Resultados: Los anticuerpos producidos fueron útiles en ensayos de Western blot e inmunofluorescencia y se reportó por primera vez un anticuerpo policlonal anti-NS3 que permitió la inmunoprecipitación de la proteína viral y la detecta con Western blot sin necesidad de inducir sobreexpresión de NS3 o de usar extractos de células marcados metabólicamente con radioisótopos. Conclusión: Las proteínas recombinantes expresadas y los anticuerpos producidos constituyen herramientas valiosas para estudiar procesos infecciosos del DENV que involucren a la proteína NS3 y evaluar pruebas dirigidas a interferir las funciones de esta proteína.

Abstract Introduction: Dengue is a disease caused by one of four serotypes of the dengue virus (DENV) and is endemic in approximately 130 countries. The incidence of dengue has increased dramatically in recent decades, as well as the frequency and magnitude of outbreaks. Despite all efforts, there are no prophylactic or therapeutic treatments for the disease. Accordingly, research on the processes governing the DENV infection cycle is essential to develop vaccines or antiviral therapies. One of the most attractive DENV molecules to investigate is nonstructural protein 3 (NS3), which is essential for viral replication and a major immune target for infection. Objective: To produce antibodies to support future studies on NS3 and its cellular interactions with other proteins. Materials and methods: Two recombinant proteins of the helicase domain of DENV NS3 serotype 2 were expressed, and used to immunize mice and produce polyclonal antibodies. Results: The antibodies produced were useful in Western blot and immunofluorescence tests. We report an NS3 antibody that immunoprecipitates the viral protein and detects it in Western blot with no need to over-express it or use cell extracts with metabolic radiolabeling.

DEAD/DExH-Box RNA Helicases in Selected Human Parasites

DEAD/DExH-box RNA helicases catalyze the folding and remodeling of RNA molecules in prokaryotic and eukaryotic cells, as well as in many viruses. They are characterized by the presence of the helicase domain with conserved motifs that are essential for ATP binding and hydrolysis, RNA interaction, and unwinding activities. Large families of DEAD/DExH-box proteins have been described in different organisms, and their role in all molecular processes involving RNA, from transcriptional regulation to mRNA decay, have been described. This review aims to summarize the current knowledge about DEAD/DExH-box proteins in selected protozoan and nematode parasites of medical importance worldwide, such as Plasmodium falciparum, Leishmania spp., Trypanosoma spp., Giardia lamblia, Entamoeba histolytica, and Brugia malayi. We discuss the functional characterization of several proteins in an attempt to understand better the molecular mechanisms involving RNA in these pathogens. The current data also highlight that DEAD/DExH-box RNA helicases might represent feasible drug targets due to their vital role in parasite growth and development.