Role of Epstein-Barr Virus in Glioblastoma.

Gliomas are the most common and most lethal primary malignant adult brain tumors, and glioblastomas are the most frequent. Several risk factors are involved in their pathogenesis; these include environmental factors as well as host factors. The etiology of most gliomas remains unknown. Epstein-Barr Virus (EBV), a member of the Herpesviridae family, was the first tumoral virus to be described, and several viruses in connection with cancer were discovered thereafter. During the complex interaction between host and EBV, several events take place. In the context of survival, EBV can drive its host cells with subsequent disruption of the cellular machinery, leading to tumorigenesis as the final outcome. Thus, the EBV infection has been associated with different tumors. In this review, we discuss EBV and cancer. We have analyzed previously published papers and have conducted a critical analysis on the role of the viral infection in glioblastoma. Several works have described the presence of the virus, but none have shown a conclusive association. Thus, there is need to continue analyzing the interaction between host and virus to determine whether the viral presence is incidental or has some association with glioblastoma.

Bioinformatics prediction of siRNAs as potential antiviral agents against dengue viruses.

Dengue virus (DENV 1-4) represents the major emerging arthropod-borne viral infection in the world. Currently, there is neither an available vaccine nor a specific treatment. Hence, there is a need of antiviral drugs for these viral infections; we describe the prediction of short interfering RNA (siRNA) as potential therapeutic agents against the four DENV serotypes. Our strategy was to carry out a series of multiple alignments using ClustalX program to find conserved sequences among the four DENV serotype genomes to obtain a consensus sequence for siRNAs design. A highly conserved sequence among the four DENV serotypes, located in the encoding sequence for NS4B and NS5 proteins was found. A total of 2,893 complete DENV genomes were downloaded from the NCBI, and after a depuration procedure to identify identical sequences, 220 complete DENV genomes were left. They were edited to select the NS4B and NS5 sequences, which were aligned to obtain a consensus sequence. Three different servers were used for siRNA design, and the resulting siRNAs were aligned to identify the most prevalent sequences. Three siRNAs were chosen, one targeted the genome region that codifies for NS4B protein and the other two; the region for NS5 protein. Predicted secondary structure for DENV genomes was used to demonstrate that the siRNAs were able to target the viral genome forming double stranded structures, necessary to activate the RNA silencing machinery.