Contribution of NOS3AS Variants to Susceptibility to Essential Hypertension: A Study in Kermanshah Province, Western Iran

Hypertension (HTN) is a global health challenge and increase the risk of cardiovascular disease. Hypertension has a multifactorial course of evolution, with both genetic and environmental factors playing an important role. To date, a number of genes and pathways have been proposed to be associated with HTN, among which is Nitric Oxide pathway. NO levels can be regulated by reactive oxygen species (ROS), superoxide and post-transcriptional mechanisms, including sense-anti sense interactions. NOS3AS gene encodes an antisense RNA (sONE) which is complementary to NOS3 transcript in 662 nucleotides and may regulate NOS3 in a post-transcriptional manner. In this study, we sought to define the role of NOS3AS in the pathophysiology of essential HTN. A total of 131 cases with hypertension and 115 controls were enrolled in the study. Peripheral blood was drawn from all study participants after signing the informed consent form. Three variants (rs71539868, rs12666075 and rs7830) were investigated by Tetra-ARMS PCR method. The results were then statistically analyzed. We found statistically significant association between rs7830 TT genotype, rs12666075 GT and TT genotypes with susceptibility to HTN. We failed to observe association between rs71539868 and susceptibility to HTN. The present study showed a strong association between NOS3AS variants and susceptibility to hypertension in the population of Kermanshah province. Our results may shed more light on the mechanisms of disease development and may also help to better identify genetic predispositions and individuals at risk.

The long noncoding RNA sONE represses triple-negative breast cancer aggressiveness through inducing the expression of miR-34a, miR-15a, miR-16, and let-7a

Triple-negative breast cancer (TNBC) represents an aggressive breast cancer subtype. Among young females, TNBC is the leading cause of cancer-related mortalities. Recently, long noncoding RNAs (lncRNAs) are representing a promising pool of regulators for tuning the aggressiveness of several solid malignancies. However, this still needs further investigations in TNBC. The main aim of this study is to unravel the expression pattern of sONE lncRNA and its mechanistic role in TNBC. Results showed that sONE is restrictedly expressed in TNBC patients; its expression level is inversely correlated with the aggressiveness of the disease. sONE acts as a posttranscriptional regulator to endothelial nitric oxide synthase (eNOS) and thus affecting eNOS-induced nitric oxide (NO) production from TNBC cells measured by Greiss reagent. Mechanistically, sONE is a potential tumor suppressor lncRNA in TNBC cells; repressing cellular viability, proliferation, colony-forming ability, migration, and invasion capacities of MDA-MB-231. Furthermore, sONE effects were found to be extended to affect the maestro tumor suppressor TP53 and the oncogenic transcription factor c-Myc. Knocking down of sONE resulted in a marked decrease in TP53 and increase in c-Myc and consequently altering the expression status of their downstream tumor suppressor microRNAs (miRNAs) such as miR-34a, miR-15, miR-16, and let-7a. In conclusion, this study highlights sONE as a downregulated tumor suppressor lncRNA in TNBC cells acting through repressing eNOS-induced NO production, affecting TP53 and c-Myc proteins levels and finally altering the levels of a panel of tumor suppressor miRNAs downstream TP53/c-Myc proteins.

Posttranscriptional and transcriptional regulation of endothelial nitric-oxide synthase during hypoxia: the role of microRNAs

Understanding the cellular pathways that regulate endothelial nitric oxide (eNOS, NOS3) expression and consequently nitric oxide (NO) bioavailability during hypoxia is a necessary aspect in the development of novel treatments for cardiovascular disorders. eNOS expression and eNOS-dependent NO cellular signaling during hypoxia promote an equilibrium of transcriptional and posttranscriptional molecular mechanisms that belong to both proapoptotic and survival pathways. Furthermore, NO bioavailability results not only from eNOS levels, but also relies on the presence of eNOS substrate and cofactors, the phosphorylation status of eNOS, and the presence of reactive oxygen species (ROS) that can inactivate eNOS. Since both NOS3 levels and these signaling pathways can also be a subject of posttranscriptional modulation by microRNAs (miRNAs), this class of short noncoding RNAs contribute another level of regulation for NO bioavailability. As miRNA antagomirs or specific target protectors could be used in therapeutic approaches to regulate NO levels, either by changing NOS3 mRNA stability or through factors governing eNOS activity, it is critical to understand their role in governing eNOS activity during hypoxa. In contrast to a large number of miRNAs reported to the change eNOS expression during hypoxia, only a few miRNAs modulate eNOS activity. Furthermore, impaired miRNA biogenesis leads to NOS3 mRNA stabilization under hypoxia. Here we discuss the recent studies that define miRNAs’ role in maintaining endothelial NO bioavailability emphasizing those miRNAs that directly modulate NOS3 expression or eNOS activity.