AimLupus nephritis (LN) is a severe complication of systemic lupus erythematosus (SLE). There is a great interest in using microRNAs (miRNAs) as diagnostic and prognostic biomarkers in autoimmune diseases.Materials and methodsThis study evaluated miR‐16, miR‐21, miR‐141, miR‐146a, and miR‐155 expression levels in peripheral blood mononuclear cells (PBMCs) of 55 female SLE patients with absent, inactive, or active nephritis, and 30 healthy controls (HCs) using quantitative polymerase chain reaction.ResultsMiR‐21 and miR‐155 levels were significantly greater in the active nephritis group than in the absent, inactive or HC groups. Moreover, receiver operating characteristic and logistic regression analyses revealed miR‐21 and miR‐155 were significant risk factors for LN.ConclusionOverexpression of miR‐21 and miR‐155 in PBMCs may participate in LN pathophysiology and these miRNAs could be used as biomarkers for the condition.

MiRNAs are endogenous, single stranded ~22-nucleotide non-coding RNAs (ncRNAs) which are transcribed by RNA polymerase II and mediate negative post-transcriptional gene regulation through binding to 3'untranslated regions (UTR), possibly open reading frames (ORFs) or 5'UTRs of target mRNAs. MiRNAs are involved in the normal physiology of eukaryotic cells, so dysregulation may be associated with diseases like cancer, and neurodegenerative, heart and other disorders. Among all cancers, lung cancer, with high incidence and mortality worldwide, is classified into two main groups: non-small cell lung cancer and small cell lung cancer. Recent promising studies suggest that gene expression profiles and miRNA signatures could be a useful step in a noninvasive, low-cost and repeatable screening process of lung cancer. Similarly, every stage of lung development during fetal life is associated with specific miRNAs. Since lung development and lung cancer phenomena share the same physiological, biological and molecular processes like cell proliferation, development and shared mRNA or expression regulation pathways, and according to data adopted from various studies, they may have partially shared miRNA signature. Thus, focusing on lung cancer in relation to lung development in miRNA studies might provide clues for lung cancer diagnosis and prognosis.

Sulfur mustard (SM) affects divergent cellular pathways including cell cycle, apoptosis, necrosis, and inflammatory responses. SM-induced lesions in skin include late-onset hyper-pigmentation, xerosis, and atrophy. It seems that TGF-b signaling pathway is a major player for SM pathogenesis. Here, we have employed a real-time polymerase chain reaction (PCR) approach to evaluate the expression alterations of all TGF-b variants and their receptors in skin biopsies obtained from 10 Iran-Iraq war veterans. Using specific LNA primers, the expression alteration of a TGF-bR2 regulator, miR-20a, and TGF-b downstream target, miR-21, was also assessed in the same samples Our real-time PCR data revealed a significant down-regulation of TGF-b1 and TGF-bR2, the major mediators of TGF-b signaling pathway, in skin biopsies of SM-exposed patients (p = 0.0015 and p = 0.0115, respectively). Down-regulation of TGF-b signaling pathway seems to contribute in severe inflammation observed in SM-exposed patients' tissues. MiR-20a and miR-21, as two important TGF-b associated microRNAs (miRNAs), were also down-regulated in SM-exposed skin lesions, compared to those of control group (p = 0.0003). Based on our findings, these miRNAs could be directly or indirectly involve in the pathogenesis of SM. Altogether, our data suggest the suitability of TGF-b1, TGF-bR2, as well as miR-20a and miR-21 as potential biomarkers for diagnosis and treatment of SM-exposed patients.

Sulfur mustard (SM) or mustard gas is a chemical alkylating agent that causes blisters in the skin (blister gas), burns the eyes and causes lung injury. Some major cellular pathways are involved in the damage caused by mustard gas such as NF-κb signaling, TGF-β signaling, WNT pathway, inflammation, DNA repair and apoptosis. MicroRNAs are non-coding small RNAs (19–25 nucleotides) that are involved in the regulation of gene expression and are found in two forms, extracellular and intracellular. Changes in the levels of extracellular microRNAs are directly associated with many diseases, it is thus common to study the level of extracellular microRNAs as a biomarker to determine the pathophysiologic status. In this study, 32 mustard gas injured patients and 32healthy subjects participated. Comparative evaluation of miR-9 and miR-143 expression in urine samples was performed by Real Time PCR and Graph Pad software. The Mann Whitney t-test analysis of data showed that the expression level of miR-143 and miR-9 had a significant decrease in sulfur mustard individuals with the respective p-value of 0.0480 and 0.0272 compared to normal samples, with an imbalance of several above mentioned pathways. It seems that reducing the expression level of these genes has a very important role in the pathogenicity of mustard gas injured patients.