: The central dogma of molecular biology explains the flow of genetic information from DNA to functional products such as proteins. In most cases, a linear relationship with high correlation coefficient exists between the concentration of mRNA, the middle man, and the functional product. Untranslated regions (UTRs) of RNA form considerable base pairing that contributes to the secondary and tertiary structures of mRNA. The interaction between the mRNA secondary structures (cis-elements), RNA-binding proteins (RBP) and miRs (trans-element) are critical determinants of mRNAs' fate and stability. Among different viral families, the positive sense (+) RNA viruses use the simplest possible strategy of replication and expression; as the same molecule functions both as a genome and mRNA. Additionally, nucleotide composition and codon usage of +RNA viruses are the closest to human codon adaptation index (CAI). Since the origin of replication of viral intermediate RNA molecules is at the 3'-end of the genome, the 3'UTR plays a role in viral RNA replication. Moreover, the messenger role of RNA likely places functional demands on the 3'UTR to serve a role typical of cellular mRNA. This article reviews the effect of 3'UTR of RNA viruses with positive sense and genomes on mRNA stability and translation improvement. A range of animal (e.g., Dengue, Sindbis, Corona and Polio) and plant (Barley yellow dwarf, Brome mosaic, Turnip crinkle, Tobacco mosaic, Cowpea mosaic and Alfalfa mosaic) viruses are examined to highlight the role of 3'UTR in viral survival and as a potential target for pharmaceutical applications.

Nonsteroidal anti‐inflammatory drugs (NSAIDs) are known to exhibit antitumor activities. Among the very well‐known oncogenes in breast cancer is zinc finger protein 703 (ZNF703) and cyclooxygenase‐2 (COX‐2). Numerous reports indicate a direct link among apoptosis resistance, chemotherapy resistance, and increased expression of ZNF703. In the present study, the expression level of ZNF703 was compared in human breast cancer tissue, healthy breast tissue, and MCF‐7 breast cancer cell line by a real‐time PCR. We also investigated the inhibitory effect of anti‐ZNF703 RNAi interference (RNAi) and ibuprofen, either individually or in combination, on MCF‐7 cell survival and apoptosis. Results showed a 93.3% and fourfold increase in the expression of ZNF703 in breast cancer tissue and MCF‐7 cell line, respectively. Ibuprofen inhibited the viability of MCF‐7 cells in a concentration‐dependent manner. Ibuprofen alone or in combination with anti‐ZNF703 RNA reduced the expression of ZNF703, induced apoptosis, reduced mitochondrial membrane potential, and elevated BAX and LC3A in MCF‐7 cells. Our results show that the combination of ibuprofen and anti‐ZNF703 siRNA is more effective in promoting apoptosis than each treatment alone. We report that the combination of anti‐ZNF703 RNAi with ibuprofen as the inhibitor of COX‐2 is highly effective in inhibiting MCF‐7 as a breast cancer cell line and shows therapeutic potential for breast cancer.

BACKGROUND: The market for the use of recombinant proteins for medical applications has been increasing in recent years. In many cases including fast production of significant amounts of protein for research purposes, transient transfection is the method of choice. In this regard expression vectors are one of the decisive factors in the cost-effectiveness of the production process. The genetic elements found in the 3’untranslated region (UTR) of mRNA expressed by such vectors, play an essential role in determining its stability and thus in the efficiency of the process. METHODS: In this study, the 3'UTR of matrix protein from the Measles Virus (MV) was used to construct a reporter plasmid containing Enhanced Green Fleurocent Protein (EGFP). The reporter construct was transfected into three cell lines. The effect of 3'UTR on mRNA stability was evaluated by real-time PCR. Secondary structure of the mrna was predicted based on minimum free energy. 3'UTR was analyzed in silico for the presence of binding motifs for trans-acting elements with known effects on RNA stability. RESULTS: Addition of 3’UTR of MV matrix protein sequence to the 3’ end of the mRNA, increased the EGFP- mRNA stability in time and cell-dependent manner. Analysis for the presence of known cis-acting motifs in 3’UTR indicated the presence of two PABPC1 binding sites, an RNA-binding protein, known for its stability and translation enhancing effects. CONCLUSION: Our results verified the potential of the 3'UTR region of matrix protein mRNA for improvement of transient recombinant protein production and vector design for mammalian cell hosts.

The enrichment of therapeutic protein production yield in mammalian cell cultures by modulating mRNA stability is a fairly new strategy in biotechnological applications. Here, we describe the application of 3′-untranslated region (3′UTR) from RNA viral genome to modulate mRNA stability. The data obtained showed that the use of the 3 'UTR sequence of the encephalomyocarditis virus (EMCV 3'UTR) downstream of the target gene was not able to significantly modulate the free energy density indicators of the RNA. However, the sequence influenced the stability of the mRNA (and, therefore, the amount of protein production) in a cell type and time-dependent manner, indicating a central role of mRNA-stabilizing binding sites/cellular factors in this process. Our data might be of interest for the biotechnology community to improve recombinant protein production in mammalian cell cultures and RNA-based therapy/vaccination approaches.

Background: Testis-specific gene antigen (TSGA10) mainly involves in spermatogenesis and embryogenesis. In the new defined roles, being a tumor suppressor agent or a cancer/testis antigen (CTA) is still unclear for this protein. The current study aimed to examine exact role of TSGA10 as a tumor suppressor or CTA in breast cancer and evaluate the role of microenvironment on its expression. Methods: This study evaluated the expression of TSGA10 and hypoxia-inducible factor 1α (HIF-1α) in two different breast cancer cell lines (MCF-7 and MDA-MB23) as well as their control (MCF10A) using real-time PCR. Moreover, expression of the mentioned genes evaluated in samples obtained from tumoral tissues with two types of controls: paired (tumor-free margin) and unpaired (healthy individuals). Also, in order to asses TSGA10 levels in the tumoral tissues, western blotting was performed. Furthermore, to evaluate the role epigenetic changes on TSGA10 expression, breast cancer cell lines were treated with a histone deacetylase inhibitor (HDACI) as well as H2O2 for oxidative stress induction. Results: The current study evaluated 36 patients diagnosed with breast cancer as well as 10 healthy controls. According to the results, it was shown that 35 (97.7%) and 1 (2.8%) of patients were diagnosed with ductal and lobular carcinomas respectively. The TSGA10 levels in the tumoral samples showed 1.38±0.014-fold decrease and 1.41±0.127-fold increase compared with their paired (P<0.001) and unpaired (P<0.001) controls respectively. Moreover, results of blotting in tumoral tissues expressed significant decrease in TSGA10 levels in comparison to the paired controls (P<0.01). Among the cell lines, TSGA10 expression in MCF-7 and MDA-MB23 cells had 4.9±0.283 and 4.21±0.163 folds of decrease in normoxic and 4.7±.0.283 and 7.1±0.141 folds of expression reduction in hypoxic condition respectively (all P<0.0001). Furthermore, the results showed that HIF-1α expression was up-regulated in both normoxic (P<0.01) and hypoxic (P<0.01) conditions. Also, TSGA10 expression increased up to 7.39±0.156 folds in MCF-7 cells after HDACI treatment (all P<0.01). However, MDA-MB23 cells firstly experienced a decrease and then a notable increase in TSGA10 expression (all P<0.01). Conclusion: Results of current study showed that TSGA10 seems to be tumor suppressor, however, further studies are necessary.