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Background: Acute lymphoblastic leukemia (ALL) is a malignancy that leads to altered blast cell proliferation, survival, and maturation and eventually to the lethal accumulation of leukemic cells. Recently, dysregulated expression of various micro-RNAs (miRNAs) has been reported in hematologic malignancies, especially ALL. Cytomegalovirus infection can induce ALL in otherwise healthy individuals, so a more detailed evaluation of its role in ALL-endemic areas like Iran is required. Methods: In this cross-sectional study, 70 newly diagnosed adults with ALL were recruited. The expression level of microRNA-155(miR-155) and microRNA-92(miR-92) was evaluated by real-time SYBR Green PCR. The correlations between the miRNAs mentioned above and the severity of disease, CMV infection, and acute graft vs. host disease after hematopoietic stem cell transplantation (HSCT) were assessed. B cell and T cell ALL distinction in the level of miRNAs was provided. Results: After the statistical analysis, our results indicated a marked increase in the expression of miR-155 and miR-92 in ALL patients vs. healthy controls (*P = 0.002–*P = 0.03, respectively). Also, it was shown that the expression of miR-155 and miR-92 was higher in T cell ALL compared to B cell ALL (P = 0.01–P = 0.004, respectively), CMV seropositivity, and aGVHD. Conclusion: Our study suggests that the plasma signature of microRNA expression may act as a powerful marker for diagnosis and prognosis, providing knowledge outside cytogenetics. Elevation of miR-155 in plasma can be a beneficial therapeutic target for ALL patients, with consideration of higher plasma levels of miR-92 and miR-155 in CMV + and post-HSCT aGVHD patients. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is considered the second-deadliest and third-most common malignancy worldwide. Studying the carcinogenic mechanism of bacteria or their role in aggravating cancer can be precious. Fusobacterium nucleatum (F. nucleatum) is one of the important bacteria in the occurrence and spread of CRC. In this study, we investigated the expression levels of miR-21, miR-17-5P, miR-155, and the relative frequency of F. nucleatum in biopsy samples from patients with CRC. Method: DNA and RNA samples were extracted using a tissue extraction kit, and then cDNAs were synthesized using a related kit. Based on the sequence of miR-17-5P, miR-21, and miR-155 genes, F. nucleatum specific 16srRNA and bacterial universal16srRNA specific primers were selected, and the expression levels of the target genes were analyzed using the Real-Time PCR method. Results: The expression level of miR-21, miR-17-5P, and miR-155 genes showed a significant increase in the cancer group. Also, the expression of the mentioned miRNAs was significantly raised in the positive samples for F. nucleatum presence. The relative frequency of F. nucleatum in the cancer group was significantly increased compared to the control group. Conclusion: Due to the changes in the expression of genes involved in causing CRC in the presence of F. nucleatum, it is possible to prompt identification and provide therapeutic solutions to cancer patients by studying their microbial profiles and the expression changes of different selected genes. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are a class of small non coding regulatory RNAs that have key functions in multiple cell processes. Deregulation of these tiny miRNAs is involved in various human diseases. MiR-155 is one of the multifunctional miRNA that its over-expression has been found to be associated with different kinds of cancer such as leukemia, breast and colon cancers. It is thought that deregulation and over-expression of this microRNA may be associated with PC12 cell proliferation. So, the aim of this study was to investigate the role of miR-155 expression on PC12 cell growth. For this reason, PC12 cells were cultured and transfected by 3 different concentration (25, 50 and 75 nmol) of either LNA anti-miR-155 or scramble antisense in 24-well plate. Then, total RNA was extracted from transfected cells. miRNA cDNAs were synthesized from isolated total RNA. In the second step, miR-155 expression level was analyzed using the quantitative real-time polymerase chain reaction (QRT-PCR). MTT test was performed to evaluate cell viability. In the next step, apoptosis assay was assessed to investigate anti miR-155 effect on PC12 cells death. Obtained results were analyzed with t-test. MTT test revealed that cell viability of transfected cells with 75 nM of anti-miR- 155 to be reduced by half of the control and scramble groups (0.5 vs. 0.97 and 0.94). Our data suggest that miR-155 over-expression is associated with PC12 cell growth. So, miR-155 down regulation by anti-miR-155 could open up new ways to restrain brain tumor growth, as anti-miR-155 causes PC12 cells to repress. [ABSTRACT FROM AUTHOR]

Aim: Lupus 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 Methods: This 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., Results: MiR-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., Conclusion: Overexpression of miR-21 and miR-155 in PBMCs may participate in LN pathophysiology and these miRNAs could be used as biomarkers for the condition., (© 2018 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.)

Introduction: MicroRNAs (miRNAs) are involved in the pathogenesis of inflammatory diseases. MiR-146 and miR-155 emerged as key regulators of the immune response. This study designed to analyze the miR-146a and miR-155 expression in patients with Behcet's disease (BD) and investigated their association with the expression of tumor necrosis factor-alpha (TNF-α) and cytotoxic T lymphocyte associated antigen-4 (CTLA-4) genes., Methodology: In a case-control study, 47 Iranian Azeri BD patients and 61 age- and sex matched healthy controls recruited to the study. Peripheral blood mononuclear cells (PBMCs) were isolated from EDTA blood tubes by Ficoll density-gradient centrifugation. Genomic DNA samples of BD and healthy controls were extracted using the rapid genomic DNA extraction method from the peripheral blood collected in tubes containing EDTA. Total RNA was extracted from the PBMCs according to the TRIzol protocol. MiR-146a, miR-155, TNF-α and CTLA-4 expression were studied using real-time PCR., Results: MiR-155 and TNF-α expression was significantly increased, whilst CTLA-4 expression was significantly decreased in the PBMCs of BD patients. There was no significant difference in the miR-146a expression rate between BD patients and controls. A positive correlation between miR-155 and TNF-α expression and negative correlation between miR-155 and CTLA-4 expression were observed. No significant association was observed between the expression of miR-155, miR-146a, TNF-α and CTLA-4 genes with BD activity. MiR-155 and miR-146a expression rate were significantly higher in patients with uveitis and phlebitis, respectively., Discussion and Conclusion: The expression of miR-155 increased in BD and associated with upregulation of TNF-α and downregulation of CTLA-4 genes., (Copyright © 2018 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.)