MiR-155 and its functional variant rs767649 contribute to the susceptibility and survival of hepatocellular carcinoma

Association of HOTAIR, MIR155HG, TERC, miR-155, -196a2, and -146a Genes Polymorphisms with Papillary Thyroid Cancer Susceptibility and Prognosis

Polymorphisms in long non-coding RNA and microRNA genes may play a significant role in the susceptibility and progression of papillary thyroid carcinoma (PTC). The current study investigates the polymorphisms HOTAIR rs920778, MIR155HG rs1893650, TERC rs10936599, miR-155 rs767649, miR-196a2 rs11614913 and miR-146a rs2910164 in 102 PTC patients and 106 age- and sex-matched controls of the Caucasian Serbian population, using real-time PCR. We observed differences in genotype distributions of the HOTAIR rs920778 (p = 0.016) and MIR155HG rs1893650 (p = 0.0002) polymorphisms between PTC patients and controls. HOTAIR rs920778 was associated with increased PTC susceptibility (adjusted OR = 1.497, p = 0.021), with the TT variant genotype increasing the risk compared to the CC genotype (OR = 2.466, p = 0.012) and C allele carriers (CC + CT) (OR = 1.585, p = 0.006). The HOTAIR rs920778 TT genotype was associated with lymph node metastasis (p = 0.022), tumor recurrence (p = 0.016), and progression-free survival (p = 0.010) compared to C allele carriers. Multivariate Cox regression revealed that ATA risk (HR = 14.210, p = 0.000004) and HOTAIR rs920778 (HR = 2.811, p = 0.010) emerged as independent prognostic factors in PTC. A novel polymorphism, MIR155HG rs1893650, was negatively correlated with susceptibility to PTC, with TC heterozygotes exerting a protective effect (OR = 0.268, p = 0.0001). These results suggest that the polymorphisms HOTAIR rs920778 and MIR155HG rs1893650 could be potential prognostic and risk biomarkers in papillary thyroid carcinomas.

SPOP regulates the expression profiles and alternative splicing events in human hepatocytes

Speckle type BTB/POZ protein (SPOP) may have cancer promoting or inhibiting effects. At present, the role of SPOP in hepatocellular carcinoma (HCC) has rarely been studied. In this study, to investigate the effects of SPOP in HCC and elucidate the underlying molecular mechanisms of its relationship with genes, differentially expressed genes (DEGs) were classified through RNA sequencing. The gene ontology analysis and Kyoto Encyclopedia of Genes and Genomes functional pathway analysis were used to further predict the function of DEGs after the overexpression of SPOP. The biological function of SPOP-regulated alternative splicing events in cells is comprehensively assessed. The Cancer Genome Atlas database and Gene Expression Omnibus dataset were performed to evaluate the correlation between SPOP and HCC progression. Due to SPOP overexpression, 56 DEGs in the HCC related pathway were further identified. The results showed that SPOP overexpression facilitated the cell proliferation and changed the gene expression profiles of human normal hepatocytes. SPOP-regulated alternative splicing events were involved in pathways associated with cellular processes, metabolism, environmental information procession, organismal systems, and so on. In conclusion, SPOP may potentially exhibit tumor-promoting effects, necessitating further investigations to unveil its molecular mechanisms comprehensively.

Vitamin D and miRNA-155 in Behçet's Disease: Possible Association with the Disease and Disease Activity

Background

Vitamin D (vit D) controls inflammation and immunity. In Behçet's disease (BD), microRNA-155 is recognized as a significant immune response regulator. We aimed to investigate the role of vit D on immunomodulation and downregulation of inflammatory pathways associated with BD and detect the role of miRNA-155 in BD.

Methods

miRNA-155 expression by Real Time -Polymerase Chain Reaction (RT-PCR), and vit D, nuclear factor Kappa-light-chain-enhancer of activated B cells (NF-κB), and Tumor necrosis fact of TNF-α) expression by Enzyme Linked Immunosorbent Assay (ELISA) were assessed.

Results

BD patients had a significantly higher relative expression of microRNA-155 (P< 0.001), it was significantly related to vascular manifestations (P< 0.001). Vit D relative expression was significantly low in BD (P< 0.001). There was a significant rise in miRNA-155 in the active group compared to the inactive group (P< 0.001). A significant decrease in vit D levels (IU) was found in inactive and active individuals suffering from BD when compared to controls (P< 0.001). A significant rise was found in vit D levels in inactive BD cases (P< 0.001). A significant positive correlations were found between miRNA-155, NF-κB, TNF-α, and negative correlations with vit D relative expression in BD patients.

Conclusions

miRNA-155 relative expression is higher in BD is significantly related to vascular manifestations. It may have a relationship to disease activity. Vitamin D relative expression is significantly low in BD patients, which can significantly influence immunomodulatory BD therapy. Vitamin D deficiency linked to active BD.

The role of miR-155 on liver diseases by modulating immunity, inflammation and tumorigenesis

The liver is a well-known metabolic organ that can be susceptible to external stimuli to affect its normal physiological function. Worldwide, the morbidity and mortality of liver diseases are skyrocketing every year, causing human health crises. Recently, new approaches such as biotechnology have been introduced to achieve optimal treatment and prognostic management of liver diseases. microRNAs (miRNAs), a kind of small non-coding RNA molecule, have the advantages of biodiversity, wide distribution and numerous members. Among these miRNAs, miR-155 is an important regulator of inflammation, immunity and tumorigenesis. In this review, the PubMed and Web of Science databases were searched from 2009 to 2022. After inclusion and exclusion, 64 articles were selected for a systematic review to comprehensively summarize the mechanisms of miR-155 regulating inflammation, immunity and tumorigenesis in liver diseases and liver cancer, covering in vitro, in vivo and clinical studies. Existing preclinical studies and clinical trials have listed that the up-regulation and down-regulation of miR-155 are significant in alcoholic liver injury, viral hepatitis, autoimmune hepatitis, infectious liver injury, liver transplantation and liver cancer. The immune and inflammation effects of miR-155 are manifested by regulating macrophage polarization, NK cell killing, Th17 cell and Th1/Th2 cell differentiation. Additionally, miR-155 is also committed to participating in the cell cycle, invasion and metastasis, immune escape and other processes to promote and intensify the development of liver cancer. In conclusion, miR-155 is not only a biomarker for the diagnosis and prognosis of liver diseases, but also plays a therapeutic role via regulating immunity, inflammation and tumorigenesis.

miR-155 rs767649 T>A gene polymorphism is associated with downregulation of miR-155 expression, suppressor of cytokine signaling-1 overexpression, and low probability of metastatic tumor at the time of breast cancer diagnosis

Background

MicroRNA-155 is a key player in inflammatory reactions, carcinogenesis, and tumor development. In this study, polymorphism of miRNA-155 rs767649 T>A and its gene and suppressor of cytokine signaling-1 (SOCS-1) expression were investigated in relation to cancer susceptibility and development in breast cancer (BC) patients.

Materials and Methods

Polymorphism of miRNA-155 rs767649 T>A was evaluated between a population of 174 patients with BC and 129 controls using restriction fragment length polymorphism and the expression of miR-155 and SOCS-1 were examined in peripheral blood mononuclear cells (PBMCs) by real-time polymerase chain reaction.

Results

TT genotype of miR-155 rs767649 T>A was associated with higher level of miR-155 in PBMCs of BC patients relative to AT and AA genotypes (21.76 ± 4.4, 4.046 ± 1.35, 2.56 ± 0.81, respectively; P < 0.001) and increased lymph node metastasis (r = 0.292, P = 0.001), not BC susceptibility (P = 0.402 and P = 0.535; respectively). TT genotype of miR-155 rs767649 T>A was associated with less gene expression of SOCS-1 in PBMCs of BC patients compared to AT and AA genotypes (1.173 ± 0.57, 0.92 ± 0.827, 5.512 ± 0.92, respectively; P = 0.003).

Conclusion

This study demonstrated for the first time the association between the T allele of the rs767649 T>A polymorphism in the pre-MIR155 gene and higher expression of miR-155, lower expression of SOCS-1, and swift latent progression in newly diagnosed BC patients. Thus, miR-155 may play a critical role in BC pathogenesis.

Dysregulated miRNAs network in the critical COVID-19: An important clue for uncontrolled immunothrombosis/thromboinflammation

Known as a pivotal immunohemostatic response, immunothrombosis is activated to restrict the diffusion of pathogens. This beneficial intravascular defensive mechanism represents the close interaction between the immune and coagulation systems. However, its uncontrolled form can be life-threatening to patients with the critical coronavirus disease 2019 (COVID-19). Hyperinflammation and ensuing cytokine storm underlie the activation of the coagulation system, something which results in the provocation of more immune-inflammatory responses by the thrombotic mediators. This vicious cycle causes grave clinical complications and higher risks of mortality. Classified as an evolutionarily conserved family of the small non-coding RNAs, microRNAs (miRNAs) serve as the fine-tuners of genes expression and play a key role in balancing the pro/anticoagulant and pro-/anti-inflammatory factors maintaining homeostasis. Therefore, any deviation from their optimal expression levels or efficient functions can lead to severe complications. Despite their extensive effects on the molecules and processes involved in uncontrolled immunothrombosis, some genetic agents and uncontrolled immunothrombosis-induced interfering factors (e.g., miRNA-single nucleotide polymorphysms (miR-SNPs), the complement system components, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases, and reactive oxygen species (ROS)) have apparently disrupted their expressions/functions. This review study aims to give an overview of the role of miRNAs in the context of uncontrolled immunothrombosis/thromboinflammation accompanied by some presumptive interfering factors affecting their expressions/functions in the critical COVID-19. Detecting, monitoring, and resolving these interfering agents mafy facilitate the design and development of the novel miRNAs-based therapeutic approaches to the reduction of complications incidence and mortality in patients with the critical COVID-19.

Association between genetic variants of microRNA-21 and microRNA-155 and systemic lupus erythematosus: A case-control study from a Chinese population

Background

Systemic lupus erythematosus (SLE) is a common autoimmune disease, and its pathogenesis remains unclear. The alteration of genetic materials is believed to play a role in SLE development. This study evaluated the association between the genetic variants of microRNA‐21 (miR‐21) and microRNA‐155 (miR‐155) and SLE.

Methods

The SNaPshot genotyping method was used to detect the genotypes of selected SNPs in patients and controls. The expression of miR‐21 and miR‐155 was analyzed using reverse transcription‐quantitative polymerase chain reaction (RT‐qPCR). The functional annotation and the biological effects of SNPs were assessed by HaploReg V4.1 and Regulome DB V2.0 software. The Hardy–Weinberg equilibrium test was used to gather statistics, and odds ratios (ORs) and 95% confidence intervals (CIs) were evaluated by logistic regression.

Results

The distribution difference of TA genotype in rs767649 was observed (TA vs. T/T: OR = 0.68, 95%CI, 0.48–0.95, p = 0.026). There was a significant difference in the T/A + A/A (T/A + A/A vs. T/T: OR = 0.68, 95%CI, 0.49–0.94, p = 0.020). A significant difference in T allele distribution was found in the depressed complement of SLE (T vs. A: OR = 0.67, 95%CI, 0.47–0.95, p = 0.026). There were significant differences in genetic variants of rs13137 between the positive and the negative SSB antibodies (Anti‐SSB) (T vs. A: OR = 0.67, 95%CI, 0.47–0.95, p = 0.026; T/A + T/T vs. AA: OR = 2.23, 1.18–4.49, p = 0.013). The expression levels of miR‐21 and miR‐155 were significantly higher in patients than in controls (p < 0.001).

Conclusions

This study provides novel insight that genetic variants of rs767649 and rs13137 are associated with susceptibility to SLE.

MiR-146a and miR-155 polymorphisms in Egyptian patients with Behcet's disease

INTRODUCTION

The current study was designed to analyze whether polymorphisms of miR-146a and miR-155 are related to Behçet's disease (BD) in the Egyptian population.

MATERIAL AND METHODS

A total of 96 unrelated BD patients and 100 healthy subjects were genotyped for miR-146a (rs2910164) and miR-155 (rs767649) using real-time polymerase chain reaction.

RESULTS

The results showed significant elevation in the frequency of rs2910164 GG and CC genotypes in BD patients compared with controls (adjusted OR = 22.156, 95% CI: 4.728-103.818; p < 0.001 and adjusted OR = 40.358, 95% CI: 8.928-182.440; p < 0.001, respectively). Also, the rs2910164 G allele conferred a higher risk of developing BD (adjusted OR = 3.665, 95% CI: 2.013-6.671; p < 0.001). MiR-146a (rs2910164) polymorphism was a risk factor for susceptibility to BD in dominant, recessive and additive models of inheritance (all p < 0.001), while the miR-155 (rs767649) polymorphism was a risk factor in the recessive model only (p = 0.021). GG and CG genotypes of rs2910164 were associated with higher Behcet's disease current activity index (BDCAI) and ocular involvement compared with CC genotype (p = 0.005 and p = 0.004, respectively). Genotype AT of rs767649 was related to higher BDCAI (p = 0.026) compared with TT and AA genotypes.

CONCLUSIONS

miR-146a (rs2910164) and miR-155 (rs767649) are likely to play an important role in the Egyptian population in development of BD and also influence disease severity.

Non-coding RNAs in melanoma: Biological functions and potential clinical applications

Malignant melanoma (MM) is a malignant tumor that originates from melanocytes and has a high mortality rate. Therefore, early diagnosis and treatment are very important for survival. So far, the exact molecular mechanism leading to the occurrence of melanoma, especially the molecular metastatic mechanism, remains largely unknown. Non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNA (circRNAs), have been investigated and found to play vital roles in regulating tumor occurrence and development, including melanoma. In this review, we summarize the progress of recent research on the effects of ncRNAs on melanoma and attempt to elucidate the role of ncRNAs as molecular markers or potential targets that will provide promising application perspectives on melanoma.

miR-155 T/A (rs767649) and miR-146a A/G (rs57095329) single nucleotide polymorphisms as risk factors for chronic hepatitis B virus infection among Egyptian patients

Genetic variants in microRNAs (miRNAs) can alter the miRNAs expression and/or function, accordingly, affecting the related biological pathways and disease risk. Dysregulation of miR-155 and miR-146a expression levels has been well-described in viral hepatitis B (HBV). In the current study, we aimed to assess rs767649 T/A and rs57095329 A/G polymorphisms in miR-155, and miR-146a genes, respectively, as risk factors for Chronic HBV (CHBV) in the Egyptian population. Also, we aimed to do in silico analysis to investigate the molecules that primarily target these miRNAs. One hundred patients diagnosed as CHBV and one hundred age and sex-matched controls with evidence of past HBV infection were genotyped for miR-155 (rs767649) and miR-146a (rs57095329) using real-time polymerase chain reaction. The rs767649 AT and AA genotypes in CHBV patients confer four folds and ten folds risk respectively, as compared to control subjects [(AOR = 4.245 (95%CI 2.009–8.970), p<0.0001) and AOR = 10.583 (95%CI 4.012–27.919), p<0.0001, respectively)]. The rs767649 A allele was associated with an increased risk of developing CHBV (AOR = 2.777 (95%CI 1.847–4.175), p<0.0001). There was a significant difference in the frequency of rs57095329 AG and GG genotypes in CHBV patients compared to controls. AG and GG genotypes showed an increase in the risk of developing CHBV by about three and six folds respectively [AOR = 2.610 (95%CI 1.362–5.000), p = 0.004] and [AOR = 5.604 (95%CI 2.157–14.563), p<0.0001].We concluded that rs57095329 and rs767649 SNPs can act as potential risk factors for the development of CHBV in the Egyptian population.

The Role of miR-155 in Nutrition: Modulating Cancer-Associated Inflammation

Nutrition plays an important role in overall human health. Although there is no direct evidence supporting the direct involvement of nutrition in curing disease, for some diseases, good nutrition contributes to disease prevention and our overall well-being, including energy level, optimum internal function, and strength of the immune system. Lately, other major, but more silent players are reported to participate in the body’s response to ingested nutrients, as they are involved in different physiological and pathological processes. Furthermore, the genetic profile of an individual is highly critical in regulating these processes and their interactions. In particular, miR-155, a non-coding microRNA, is reported to be highly correlated with such nutritional processes. In fact, miR-155 is involved in the orchestration of various biological processes such as cellular signaling, immune regulation, metabolism, nutritional responses, inflammation, and carcinogenesis. Thus, this review aims to highlight those critical aspects of the influence of dietary components on gene expression, primarily on miR-155 and its role in modulating cancer-associated processes.

Dairy consumption and hepatocellular carcinoma risk

This review provides epidemiological and translational evidence for milk and dairy intake as critical risk factors in the pathogenesis of hepatocellular carcinoma (HCC). Large epidemiological studies in the United States and Europe identified total dairy, milk and butter intake with the exception of yogurt as independent risk factors of HCC. Enhanced activity of mechanistic target of rapamycin complex 1 (mTORC1) is a hallmark of HCC promoted by hepatitis B virus (HBV) and hepatitis C virus (HCV). mTORC1 is also activated by milk protein-induced synthesis of hepatic insulin-like growth factor 1 (IGF-1) and branched-chain amino acids (BCAAs), abundant constituents of milk proteins. Over the last decades, annual milk protein-derived BCAA intake increased 3 to 5 times in Western countries. In synergy with HBV- and HCV-induced secretion of hepatocyte-derived exosomes enriched in microRNA-21 (miR-21) and miR-155, exosomes of pasteurized milk as well deliver these oncogenic miRs to the human liver. Thus, milk exosomes operate in a comparable fashion to HBV- or HCV- induced exosomes. Milk-derived miRs synergistically enhance IGF-1-AKT-mTORC1 signaling and promote mTORC1-dependent translation, a meaningful mechanism during the postnatal growth phase, but a long-term adverse effect promoting the development of HCC. Both, dietary BCAA abundance combined with oncogenic milk exosome exposure persistently overstimulate hepatic mTORC1. Chronic alcohol consumption as well as type 2 diabetes mellitus (T2DM), two HCC-related conditions, increase BCAA plasma levels. In HCC, mTORC1 is further hyperactivated due to RAB1 mutations as well as impaired hepatic BCAA catabolism, a metabolic hallmark of T2DM. The potential HCC-preventive effect of yogurt may be caused by lactobacilli-mediated degradation of BCAAs, inhibition of branched-chain α-ketoacid dehydrogenase kinase via production of intestinal medium-chain fatty acids as well as degradation of milk exosomes including their oncogenic miRs. A restriction of total animal protein intake realized by a vegetable-based diet is recommended for the prevention of HCC.

MicroRNA polymorphism: A target for diagnosis and prognosis of hepatocellular carcinoma?

Hepatocellular carcinoma (HCC) is a life-threatening cancer of the digestive system, with complex pathogenesis affected by a broad spectrum of genetic and epigenetic factors. Among several factors, microRNAs (miRNAs), which are considered regulators of the post-transcriptional gene expression, play important roles in determining the malignant phenotype of HCC. In recent years, the advances in molecular genetics have resulted in the characterization of complex genetic factors and in the identification of epigenetic mechanisms of diseases. Accumulating data have suggested that miRNA polymorphisms are involved in tumorigenesis and prognosis, suggesting that the miRNAs may serve as a target for HCC with regard to pathogenesis and prognosis. In the present review, a comprehensive and detailed literature search was conducted and the role of miRNA polymorphisms in the pathogenesis and prognosis of HCC is summarized. The data proposed the use of miRNAs as targets for the diagnosis and treatment of HCC.

The miR-146a SNP Rs2910164 and miR-155 SNP rs767649 Are Risk Factors for Non-Small Cell Lung Cancer in the Iranian Population

Background

Lung cancer is one of the leading causes of death worldwide. MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression and may act as both tumor suppressors and as oncogenes. The presence of single nucleotide polymorphisms (SNPs) inside the miRNA genomic region could affect target miRNA maturation, expression, and binding to its target mRNA and contribute to cancer development. Previous studies on the SNPs Rs2910164 in miR-146a and Rs767649 in miR-155 showed association with non-small cell lung cancer (NSCLC) development. Thus, the aim of this study was to detect any correlation between those SNPs in Iranian NSCLC patients.

Methods

In a small cohort study, 165 NSCLC patients and 147 noncancer controls were enrolled between Apr 2015 and Sep 2019 at the Masih Daneshvari Hospital, Tehran, Iran. Allele frequencies from the genomic DNA of blood cells were studied using PCR-RFLP and their association with the risk of lung cancer was evaluated.

Results

The rs2910164C allele (OR = 1.56, 95% CI = 1.10–2.21, p = 0.012) and CC genotype (OR = 2.93, 95% CI = 1.07–7.9, p = 0.034, respectively) were associated with a significantly increased risk for lung cancer compared to that for the GG genotype. When patients were stratified according to smoking exposure, no association with rs2910164 variants was found. The AT genotype (OR = 0.57, 95% CI = 0.33–0.99, p = 0.048) and the A allele frequency (OR = 0.58, 95% CI = 0.35–0.98, p = 0.043) in rs767649 were lower in NSCLC patients in comparison with the control group. In addition, the rs767649 AT genotype frequency in smoking controls was higher than in smoking NSCLC patients (OR = 0.44, 95% CI = 0.21–0.90, p = 0.024). No association was found between rs2910164 and rs767649 variants and stage or type of NSCLC.

Conclusion

Our finding suggests that miR-146a rs2910164 and miR-155 rs767649 polymorphisms may be considered as genetic risk factors for the susceptibility to NSCLC in the Iranian population. However, a larger multicenter study across Iran is needed to confirm these findings.

Relationship between miR-155 and miR-146a polymorphisms and susceptibility to multiple sclerosis in an Egyptian cohort

Multiple sclerosis (MS) is an autoimmune disorder of the central nervous system. It was previously demonstrated that miR-155 and miR-146a served a vital role in the pathophysiology of MS, and single nucleotide polymorphisms in miR-155 and miR-146a were found to be associated with the susceptibility to different autoimmune diseases, such as systemic lupus erythematosus, rheumatoid arthritis and type I diabetes. The aim of the present study was to analyze the association between susceptibility to MS and two genetic polymorphisms (miR-155 rs767649 A>T and miR-146a rs57095329 A>G) in a cohort of Egyptian patients. The presence of the two polymorphisms were analyzed in 114 patients with MS and 152 healthy controls using quantitative PCR. The present study demonstrated for the first time that: The TT genotype and T allele in miR-155 (rs767649 A>T) polymorphism were associated with an increased risk of MS; the miR-146a (rs57095329 A>G) mutated G allele conferred protection against the development of MS in all genetic models; miR-155 rs767649 A>T was a risk associated polymorphism of MS in females, but not in males; and miR-155 rs767649 AT/TT and miR-146a rs57095329 GG genotypes showed significantly higher distributions among patients with higher Expanded Disability Status Scale scores and secondary progressive MS subgroups. Therefore, miR-155 rs767649 polymorphism may confer susceptibility to MS, whereas miR-146a rs57095329 may be protective against MS in an Egyptian cohort.

Association of miR-155 and Angiotensin Receptor Type 1 Polymorphisms with the Risk of Ischemic Stroke in a Chinese Population

There is increasing evidence suggesting that dysregulation of miR-155 and its target angiotensin receptor type 1 (AT1R) are linked to the incidence of ischemic stroke (IS), but the underlying mechanisms remain to be clarified. In this study, we therefore sought to investigate how miR-155 and AT1R polymorphisms affect IS risk. We included 579 IS patients and 509 age-matched controls in the present analysis, genotyping individuals for the rs767649 polymorphism in miR-155, as well as for the rs1492099 and rs275653 polymorphisms in AT1R via iMLDR-TM genotyping technology. The allele and genotype frequencies for the assessed polymorphisms were comparable in IS patients and controls, without any detectable association between AT1R haplotype and IS risk. We conducted additional trial of ORG 10172 in acute stroke treatment-mediated stratification, which indicated that the AT1R rs1492099 T allele was linked to a decreased risk of large-artery atherosclerosis (LAA) stroke. We further found that those with the AT1R rs275653 AA genotype had a decreased risk of small-artery occlusion (SAO) strokes. We further confirmed elevated miR-155 expression in IS patients, but observed no link between the rs767649 polymorphism and expression of this microRNA. Similarly, rs1492099 and rs275653 polymorphisms did not impact AT1R expression levels. The miR-155 rs767649 polymorphism does not seem to be a key determinant of IS risk, whereas the AT1R rs1492099 polymorphism is linked to reduced LAA-stroke risk, and the rs275653 AA genotype is potentially protective against SAO strokes.

gga-miR-155 Enhances Type I Interferon Expression and Suppresses Infectious Burse Disease Virus Replication via Targeting SOCS1 and TANK

Infectious bursal disease (IBD) is an acute, highly contagious, and immunosuppressive avian disease caused by IBD virus (IBDV). MicroRNAs (miRNAs) are involved in host-pathogen interactions and innate immune response to viral infection. However, the role of miRNAs in host response to IBDV infection is not clear. We report here that gga-miR-155 acts as an anti-virus host factor inhibiting IBDV replication. We found that transfection of DF-1 cells with gga-miR-155 suppressed IBDV replication, while blockage of the endogenous gga-miR-155 by inhibitors enhanced IBDV replication. Furthermore, our data showed that gga-miR-155 enhanced the expression of type I interferon in DF-1 cells post IBDV infection. Importantly, we found that gga-miR-155 enhanced type I interferon expression via targeting SOCS1 and TANK, two negative regulators of type I IFN signaling. These results indicate that gga-miR-155 plays a critical role in cell response to IBDV infection.

MiR-155 Promotes Uveal Melanoma Cell Proliferation and Invasion by Regulating NDFIP1 Expression

MicroRNAs refer to small RNA molecules that destroy the messenger RNA by binding on them inhibiting the production of protein. However, the role of miR-155 in uveal melanoma metastasis remains largely unknown. In this study, we found that miR-155 was upregulated in both uveal melanoma cells and tissues. Transfection of miR-155 mimic into uveal melanoma cells led to an increase in cell growth and invasion; in contrast, inhibition of miR-155 resulted in opposite effects. Also, we identified Nedd4-family interacting protein 1 as a direct target of miR-155, and the expression of Nedd4-family interacting protein 1 was inhibited by miR-155. Furthermore, ectopic expression of Nedd4-family interacting protein 1 restored the effects of miR-155 on cell proliferation and invasion of uveal melanoma cells. In conclusion, miR-155 acts as a tumor promotor in uveal melanoma through increasing cell proliferation and invasion. Thus, miR-155 might serve as a potential therapeutic target in patients with uveal melanoma.

Polymorphisms in genes encoding miR-155 and miR-146a are associated with protection to type 1 diabetes mellitus

AIMS

Type 1 diabetes mellitus (T1DM) is characterized by severe autoimmune destruction of pancreatic beta-cells. The triggering of autoimmunity against beta-cells is probably caused by a combination of environmental and genetic risk factors. Even though much is known about the genetic of T1DM, more information is needed to completely unravel this tangled disease. MicroRNAs (miRNAs) are a class of small noncoding RNAs molecules that negatively regulate gene expression by inducing target mRNA cleavage or by inhibiting protein translation. Abnormal miRNA expressions have been described in autoimmune diseases and T1DM. Polymorphisms in genes codifying miRNAs may alter the expression of the corresponding miRNA and, thus, confer susceptibility for a given disease. Therefore, the aim of this study was to investigate whether polymorphisms in genes encoding miR-155, miR-146a, and miR-375 are associated with T1DM.

METHODS

Frequencies of the miRNA-146a rs2910164, miRNA-155 rs767649 and miRNA-375 rs6715345 polymorphisms were analyzed in 490 T1DM patients and in 469 nondiabetic subjects.

RESULTS

The miR-146a rs2910164 and miR-155 rs767649 polymorphisms were associated with protection for T1DM, and the strongest association was observed for the dominant model [odds ratio (OR) = 0.557 95% CI 0.355-0.874 and OR = 0.508, 95% CI 0.265-0.973, respectively, after adjustment for age, ethnicity, and risk HLA loci]. However, miR-375 rs6715345 frequencies did not differ between cases and controls.

CONCLUSION

MiR-146a rs2910164 and miR-155 rs767649 polymorphisms were associated with protection for T1DM.