miR-21 Expression Research Articles

MiR-223 within neutrophil axis promotes Th17 expansion by PI3K-AKT pathway in systemic lupus erythematosus

IntroductionFurther investigation is required to determine the etiology of systemic lupus erythematosus (SLE). The aim of this study is to assess the presence of miR-223 within neutrophils in SLE and investigate its impact on the expansion of Th17 cells.MethodsExperiments were performed in MRL/lpr mice, which were divided into control and miR-223 knockdown (miR-223-) group. We assessed miR-223 expression within neutrophils and Th17 expansion in MRL/lpr mice and patients with SLE using RT-PCR, luciferase reporter assay, Elisa, flow cytometry analysis. Signaling pathway, RT-PCR and western blot were conducted to elucidate the mechanism by which miR-223 within neutrophils expands Th17.ResultsWe initially identified miR-223 as a pivotal factor in the pathogenesis of SLE in both MRL/lpr mice and SLE patients. Subsequently, knockdown of miR-223 led to a significant reduction in Th17 expansion in MRL/lpr mice. Moreover, inhibition of miR-223 effectively attenuated the recruitment and activation of neutrophils in SLE. Furthermore, we found rb6-8c5 treatment alleviated lupus symptoms of MRL/lpr mice and reduce the level of Th17. Finally, we elucidated that neutrophils potentiate the induction of Th17 through the activation of thePI3K-AKT pathway mediated by miR-223 during SLE-associated Th17 expansion.ConclusionMiR-223 within neutrophil axis contributes to Th17 expansion by PI3K-AKT pathway in SLE, and miR-223 could be a therapeutic target of SLE.

MicroRNA-155 as Biomarker and Its Diagnostic Value in Breast Cancer: A Systematic Review.

The investigation of microRNAs (miRNAs) for the purpose of identifying biomarkers and new treatments for breast cancer has been gaining traction from scientists in recent years. Of all the miRNAs, miR-155 has been reportedly involved in breast cancer development as it regulates various cellular processes such as glucose uptake, proliferation, metastasis, and migration. Various efforts have been done towards researching miR-155 as a biomarker in breast cancer; however, the results were varied. The objective of the current systematic review is to compile and summarize information regarding miR-155 as a potential diagnostic biomarker for breast cancer. All eligible studies were found from SCOPUS and PubMed databases. Out of the 376 potential eligible records, only 26 original articles were selected for further assessment according to inclusion and exclusion criteria. The expressions of miR-155 in serum, plasma, biopsy, urine, nipple aspirate fluid, serum exosomes, and peripheral blood mononuclear cells were recorded and analyzed. Besides that, the expression of miR-155 was also correlated to clinicopathological features in breast cancer patients. The area under the curve (AUC) values from receiver operating characteristic (ROC) analysis used to evaluate diagnostic sensitivity and specificity of miR-155 as a diagnostic biomarker were also recorded. The limitations such as the small sampling size, the unemployment of internal controls for quantitative real-time polymerase chain reaction (RT-qPCR), and inconsistency of sensitivity as well as specificity values of miR-155 as a biomarker have been discussed. The present study proposed that miR-155 is a good diagnostic biomarker for breast cancer; however, further clinical research is required to assess the validity of miR-155 as a potential biomarker to translate the research outcomes into clinical practice.

MiR-92a aggravates metabolic syndrome via KLF2/miR-483 axis.

To exam the role of miR-92a/KLF2/miR-483 in the pathogenesis of metabolic syndrome. In this study, the serum of healthy controls and patients with metabolic syndrome were collected to detect the circulating level of miR-92a and miR-483. In vitro cultured HUVECs, overexpression or suppression of miR-92a, miR-483 or KLF2 to determine the relationship among miR-92a, KLF2 and miR-483. Ang II, ox-LDL, or high glucose treatment were used to mimic the metabolic syndrome. HUVECs or HepG2 cells were treated with Telmisartan, Atorvastatin, or metformin, the miR-483 and its target gene expression was detected. In animal experiment, ob/ob mice were chose to confirm the changes of miR-92a, KLF2, and miR-483. Compared with the healthy controls, the level of miR-92a was significantly increased, while miR-483 level was remarkably decreased in the patients with metabolic syndrome. In vitro cultured HUVECS, overexpression of miR-92a significantly reduced the expression of miR-483, but overexpression of miR-483 had no effect on miR-92a. Overexpression of KLF2 could downregulate miR-483 level, while inhibition of KLF2 had the opposite effect. When HUVECs and HepG2 were stimulated with Ang II, ox-LDL and high glucose, the expression of miR-483 was significantly decreased and its target genes was increased. Anti-miR-92a could reverse the effect. Furthermore, Telmisartan, Atorvastatin, and Metformin significantly increased miR-483 expression and decreased its target gene expression, which could be reversed by miR-92a mimic. The level of miR-92a was significantly increased in HepG2 cells, which were treated with exosomes derived from endothelial cells with miR-92a overexpression. ob/ob mice showed the similar effects. Endothelial dysfunction and fatty liver are critically involved in the pathogenesis of metabolic syndrome. MicroRNAs can mediate the cellular communication between vascular endothelial cells (ECs) and distal cell. Serum miR-92a level was higher in metabolic syndrome patients than controls. KLF2 is the target gene of miR-92a, which can increase the production of miR-483, miR-483 acts on its target genes CTGF, ET-1, and β-catenin to protect cell function. EC miR-92a is secreted out of cells into the blood, circulates through the blood to the liver, and continues to exert its biological effects after being absorbed by hepatocytes. LNA-miR-92a administration reversed endothelial cell damage and fatty liver caused by metabolic syndrome by affecting the KLF2/miR-483 pathway.

Abstract TMP119: Suppression of microRNA-145 alleviates the vascular cognitive impairment in a multiple microinfarction model

Background: Vascular cognitive impairment (VCI) is the second most frequent subtype of dementia following Alzheimer's disease. However, the underlying mechanism has not been fully understood and there is no effective treatment for VCI. MicroRNAs (miRNAs) play critical roles in the pathologies of cerebral ischemia and dementia. This study aims to identify key miRNAs that may mediate cognitive outcomes using multiple microinfarction (MMI), a VCI model. Methods: MMI was induced by the administration of cholesterol crystals (70-100µm) into the internal carotid artery. Male Wistar rats (10-12 month) subjected to MMI or sham operation were euthanized 28 days after MMI (n=8/group). Total RNAs were isolated from the striatal tissues and miRNA-sequencing was performed. AAV-PHP.Eb carrying miR-145-5p sponge was delivered by the Intracerebroventricular injection at 2 days prior to MMI to knockdown miR-145-5p. The mNSS (modified Neurological Severity Score) and cognition tests were examined at 2 weeks after MMI. Results: MiRNA-sequencing analysis showed that compared to sham rats, MMI significantly up- and down-regulated 4 and 9 miRNAs respectively. Bioinformatics analysis revealed that these miRNAs were highly associated with the oligodendrocytes/myelination (miR-210 and miR-125), BBB (miR-665 and miR-29), and inflammation (miR-322), etc. Amongst them, miR-145 was the top upregulated miRNA in the striatum after MMI. In situ hybridization demonstrated that miR-145 expression was highly upregulated in the smooth muscle cells, which was negatively correlated with the decrease of contraction marker of smooth muscle cells (SMCs). Treatment of MMI rats with AAV-miR-145 sponge significantly reduced sensorimotor deficits assayed by lower mNSS score. Furthermore, MMI rats administered AAV-miR-145 spent less time on the closed arm in the EPM (AAV-miR-145 VS control AAV: 182±28 VS 263±9 (s), P=0.01) and showed less freezing time in the OFT (AAV-miR-145 VS control AAV: 205±9 VS 246±11 (s), P=0.015), compared with those treated with control AAV. These data indicate that inhibition of miR-145 reduces depression-like behavior and cognitive deficit induced by MMI. Conclusion: Our results uncovered the deregulated miRNAs associated with myelination, white matter and vascular damage after MMI. Also, our data suggest that miR-145 could be a potential therapeutic target by the regulation of SMCs against VCI. Thus, our data provides new insights into the molecular mechanisms underlying VCI.

Andrographolide mitigates neurotoxicity induced by lipopolysaccharide or amyloid-β through modulation of miR-222-mediated p62 and NF-κBp65 expression.

MicroRNA-222 (miR-222) plays a crucial role in neurodegeneration and is up-regulated in Alzheimer's disease (AD) patients. Andrographolide (Andro) has been reported to have anti-inflammatory and neuroprotective effects, showing potential for treating AD. The relationship between Andro's anti-AD mechanism and the regulation of miR-222 was discussed in this study. Andro protected against cytotoxicity induced by lipopolysaccharide (LPS) or amyloid-β, accompanied by upregulating p62 and Nrf2 mRNA and protein, downregulating TLR4 and NF-κBp65 mRNA and protein, and increasing LC3Ⅱ protein in vitro. miRNA and mRNA sequencing results showed that Andro downregulated miR-222 and upregulated sqstm1/p62. Andro was observed to inhibit the expression of miR-222 and the phosphorylation of NF-κBp65, while simultaneously enhancing the levels of p62 and LC3Ⅱ proteins, decreasing Aβ levels, and attenuating the release of inflammatory factors in the 3xTg-AD mice. MiR-222 mimic increased NF-κBp65 mRNA and protein levels in LPS-induced cells, while miR-222 inhibitors increased p62 mRNA and protein levels as well as Nrf2 and LC3Ⅱ protein, and decreased p-NF-κBp65 protein level in LPS-induced cells. Furthermore, miR-222 mimic reversed the increase in p62 and LC3Ⅱ protein and the decrease in NF-κBp65 mRNA and protein, as well as the decrease in Tau protein levels induced by Andro in LPS-induced cells. These findings suggest that Andro plays a neuroprotective role through downregulation of miR-222 to promote p62 expression while inhibiting NF-kB p65 expression, providing new insights into the mechanism of action of Andro for treating AD.

Nimbolide attenuates hepatocellular carcinoma by regulating miRNAs 21, 145 and 221 and their target gene expression.

MicroRNAs (miRNAs) are becoming progressively emerging in cancer research from an etiologic and curative point of view. Several miRNAs act as oncogenes or tumor suppressors, which are dysregulated in numerous cancers. Our previous studies have established that nimbolide (a bioactive terpenoid from neem) attenuated hepatocellular carcinoma (HCC) through various mechanisms in mice. Here, we aimed to elucidate the effect of nimbolide in modulating specific miRNAs (21, 145, and 221) and their target genes involved in promoting inflammation and cancer cell proliferation in HCC mice. Following the induction of HCC in mice at 28weeks, nimbolide (6mg/kg b.wt.) was administered orally for four consecutive weeks. We found significantly increased hepatic expression of miR-21a-3p, miR-21a-5p, miR-221-5p and miR-221-3p whilst significantly decreased miR-145a-5p in HCC mice. Nimbolide treatment to HCC mice substantially reduced the miR-21a-5p and miR-221-3p and improved miR-145a-5p gene expression. Our in-silico study also supports these findings. Moreover, hepatic tight junction (TJ) associated proteins such as claudins 1&5 mRNA and protein were increased considerably, whilst significantly decreased hepatic claudin 2 mRNA and protein expression noted in HCC mice. Nimbolide also regulates cadherins, ROCK 1, MMP 9, cyclin D1, CDK4, NF κB and TNFα mRNA expression in HCC mice. We identified for the first time that nibmolide treatment to HCC mice significantly attenuated hepatic miRNAs 21 & 221 expressions and sheltered miR-145 expression. These findings were further confirmed with in-silico studies. Moreover, nibmolide treatment in HCC mice regulates miRNA target genes involved in cancer cell proliferation and inflammation, thereby attenuating HCC progression in mice.

Estimation of miRNA 208 Effects in Inducing Epithelial-Mesenchymal Transition by Targeting CDH2 in Breast Cancer Patients of Iraqi Population

Breast cancer is the most frequently diagnosed disease in women and remains a leading cause of cancer-related deaths worldwide. The small non-coding RNA molecule, MicroRNA-208 (miR-208), plays a crucial role in the development and advancement of numerous malignancies, including breast cancer. This study aimed to investigate miR-208 potential as an oncogene in breast cancer by examining its impact on cell motility and epithelial-mesenchymal transition (EMT). Tissue samples from 25 Iraqi women with malignant breast cancer and 25 with benign breast cancer were analysed. Total RNA was extracted from the samples and real-time reverse transcription-polymerase chain reaction (RT-PCR) was performed using SYBR Green technology to measure miR-208 expression levels. Tissue samples from both benign and malignant tumours were analysed to determine U6 gene expression. The analysis showed that the typical Ct values for benign and malignant samples were 29.83 and 29.67 respectively. No significant difference in U6 expression levels was detected between benign and malignant tumours. However, upon comparing the initial malignant and the benign tumours samples, miRNA-208 ΔΔCT values were found to be substantially lower (-7.105 and -0.781 respectively) with a p-value of less than 0.05. The study found that malignant tumours had a significantly higher miRNA-208 folding value (2.896±) compared to benign tumours which had substantially lower miRNA-208 folding values (1.591 ±0.37). The study also found that the differences were statistically significant (p-value = 1.292*). In conclusion, the study found evidence linking miR-208 to the CDH2 gene, indicating its role in the development and susceptibility to breast cancer in certain Iraqi women.

Exosomal miR-122 derived from M2 macrophages induces osteogenic differentiation of bone marrow mesenchymal stem cells in the treatment of alcoholic osteonecrosis of the femoral head

Alcoholic osteonecrosis of the femoral head (AIONFH) is caused by long-term heavy drinking, which leads to abnormal alcohol and lipid metabolism, resulting in femoral head tissue damage, and then pathological necrosis of femoral head tissue. If not treated in time in clinical practice, it will seriously affect the quality of life of patients and even require hip replacement to treat alcoholic femoral head necrosis. This study will confirm whether M2 macrophage exosome (M2-Exo) miR-122 mediates alcohol-induced BMSCs osteogenic differentiation, ultimately leading to the inhibition of femoral head necrosis. M2 macrophages were identified by flow cytometry, and the isolated exosomes were characterized by transmission electron microscopy (TEM) and Nanoparticle Tracking Analysis (NTA). Next, miR-122 was overexpressed by transfecting miR-122 mimic, and the expression of miR-122 in M2 macrophages and their exosomes was evaluated. Subsequently, the effect of exosomal miR-122 on the osteogenic differentiation ability of BMSCs was detected, including cell proliferation, expression of osteogenic-related genes (RUNX2, BMP2, OPN, ALP), and calcium nodule formation. Finally, the therapeutic effect of M2-Exo was analyzed in a rat model of AIONFH, and bone repair and pathological damage were evaluated by Micro-CT, RT-qPCR, HE, Masson staining, and immunohistochemistry (COL I). The results showed that M2 macrophages were successfully polarized, with an average M2-Exo particle size of 156.4 nm and a concentration of 3.2E + 12 particles/mL. The expression of miR-122 in M2 macrophages is significantly higher than that in M0 macrophages, and miR-122 mimic can increase the content of miR-122 in M2-Exo. miR-122 in M2-Exo can promote osteogenic differentiation of rat bone marrow BMSCs, enhance cell viability, and increase the expression of osteogenesis-related genes. After being applied to the AIONFH rat model, the injection of M2-exo and miR-122 mimics significantly improved the repair effect of articular cartilage, alleviated pathological changes, and promoted the regeneration of bone tissue. M2-macrophage-derived exosomal miR-122 induces osteogenic differentiation of bone mesenchymal stem cells in treating AIONFH.

Clinical significance of GABA, NSE, and miR-155 expression in patients with post-stroke epilepsy.

This study investigated the clinical predictive value of cerebrospinal fluid (CSF) γ-aminobutyric acid (GABA) and serum neuron-specific enolase (NSE) and microRNA-155 (miR-155) for post-stroke epilepsy (PSE) in patients with cerebral infarction (CI). A total of 69 CI patients with PSE and 84 with non-post-stroke epilepsy (N-PSE) were retrospectively enrolled, with their clinical baseline data (CI type) and the National Institute of Health Stroke Scale (NIHSS) score collected. CSF GABA and serum NSE and miR-155 expression levels were determined, with their clinical value further assessed. The results showed that the proportions of patients with cardiogenic CI, multiple infarcts, and cortical involvement and NIHSS score in PSE patients were higher than those in N-PSE patients. CSF GABA was lowly expressed and serum NSE and miR-155 were highly expressed in PSE patients. The NIHSS score negatively correlated with GABA and positively correlated with NSE and miR-155. GABA [area under the curve (AUC) = 0.906], NSE (AUC = 0.908), miR-155 (AUC = 0.862) and their combined detection (AUC = 0.963) all had certain value in the occurrence of PSE in CI patients, with their combined detection showing higher AUC than that of single detection. Briefly, CSF GABA was reduced while serum NSE and miR-155 were elevated in PSE patients. GABA and NSE combined with miR-155 had high diagnostic value for PSE occurrence in CI patients. Lowly-expressed GABA or highly-expressed NSE and miR-155 were independent risk factors for PSE in CI patients, which could provide effective guidance for the clinical diagnosis and management of PSE.

Significance of miR-122 -and miR- 150 in the pathogenicity of hepatitis B infection

Background: HBV, a contagious infection, causes chronic hepatitis, cirrhosis, and hepatocellular cancer in many people. The WHO estimates that 2 billion people are exposed to HBV annually, depending on when. The Hepadnaviridae family virus has an unfinished 3.2-kilobase double-stranded DNA molecule. Increased ALT, AST, and HBsAg positive or HBV DNA viral load are used to identify the illness. Despite global immunization campaigns, nations with low vaccination coverage and no diagnosis remain concerned. The worldwide HBV burden remains high. MicroRNAs (miRNAs) bind to mRNAs after transcription to govern gene expression, hepatitis B virus replication, and extracellular matrix development.Methods: Sixty six Iraqi HBV patients were involved in a case-sectional control study. From September 2021 to February 2022, blood samples were taken from Al-Yarmook Teaching Hospital and Central Public Health Laboratory in Baghdad. ELISA verified HBV markers, HBsAg, HBsAb, HBeAg, HBeAb, and HBcAb in all samples, and real-time PCR estimated viral load from DNA. The research found that miR122 and miR150 gene expressions affect HBV fibrosis severity.Results: The gene expression of miR-122 and miR-150 was found using RT-PCR after normalization with Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a common housekeeping gene. The analysis of variance found substantial differences between patients and controls. The research found a considerable downregulation of miRNA-122 and miRNA-150 in HBV-infected individuals.Conclusions: Depending on HBV severity, miRNA levels may vary. HBV patients, especially those with fibrosis and chronic HBV, have reduced miR122 and miR150. MiR-122 and miR-150 may be interesting HBV diagnostic, fibrosis progression, and therapeutic targets.Keywords: Hepatitis B virus; MicroRNAs (miRNAs); RT-PCR; Primers; Gene expression; Liver disease

Pine (Pinus koraiensis) Nut Oil Ameliorates Cholesterol Homeostasis and Inflammation via Modulating the miR-34a/122 Pathways in the Liver of Rats Fed a High-Cholesterol Diet.

Pine (Pinus koraiensis) nut oil (PNO) has been reported to have various beneficial effects on hepatic triglyceride accumulation and atherosclerosis in animal models. MicroRNAs (miRs) are involved in various diseases by modulating physiological processes. However, the mechanism underlying PNO's effects on the regulation of miRs involved in hepatic cholesterol homeostasis and inflammation remains unclear. This study investigated the effects of PNO on the regulation of the miR-34a/122 pathways involved in cholesterol homeostasis and inflammation in the liver using a high-cholesterol diet (HCD) rat model. Six-week-old male Sprague-Dawley rats were randomly divided into three groups (n = 8/group) and provided with (1) a cholesterol-free diet, (2) an HCD containing 1% cholesterol and 0.5% cholic acid, or (3) an HCD containing 5% PNO for 4 weeks. Lipid analysis of serum and liver, histological evaluation, and analysis of gene and protein expression were performed. PNO supplementation in HCD improved hepatic lipid profiles and elevated serum high-density lipoprotein cholesterol compared to the HCD group. PNO significantly upregulated hepatic gene expression levels of liver X receptor α and ATP-binding cassette transporter A1/G1, which are involved in cholesterol efflux (P < 0.05). Gene expressions of proinflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-1β, monocyte chemoattractant protein-1, and inducible nitric oxide synthase were downregulated by PNO (P < 0.05). PNO also suppressed TNF-α and IL-6 protein levels by 22.3% and 17.3%, respectively (P < 0.05). PNO reduced hepatic nuclear factor-kappa B activity by 16.4% and decreased nitric oxide production in the liver and serum (P < 0.05). Furthermore, hepatic miR-34a and miR-122 expressions decreased by 16.4% and 15.7% by PNO, respectively (P < 0.05). These results suggest that PNO may affect cholesterol homeostasis and inflammation, which are partially associated with the miR-34a/122 pathways in the liver under an HCD.

The Multifaceted Roles of MicroRNA-181 in Stem Cell Differentiation and Cancer Stem Cell Plasticity.

Stem cells are undifferentiated or partially differentiated cells with an extraordinary ability to self-renew and differentiate into various cell types during growth and development. The epithelial-mesenchymal transition (EMT), a critical developmental process, enhances stem cell-like properties in cells, and is associated with both normal stem cell function and the formation of cancer stem cells. Cell stemness and the EMT often coexist and are interconnected in various contexts. Cancer stem cells are a critical tumor cell population that drives tumorigenesis, cancer progression, drug resistance, and metastasis. Stem cell differentiation and the generation of cancer stem cells are regulated by numerous molecules, including microRNAs (miRNAs). These miRNAs, particularly through the modulation of EMT-associated factors, play major roles in controlling the stemness of cancer stem cells. This review presents an up-to-date summary of the regulatory roles of miR-181 in human stem cell differentiation and cancer cell stemness. We outline studies from the current literature and summarize the miR-181-controlled signaling pathways responsible for driving human stem cell differentiation or the emergence of cancer stem cells. Given its critical role in regulating cell stemness, miR-181 is a promising target for influencing human cell fate. Modulation of miR-181 expression has been found to be altered in cancer stem cells' biological behaviors and to significantly improve cancer treatment outcomes. Additionally, we discuss challenges in miRNA-based therapies and targeted delivery with nanotechnology-based systems.

MIR-155 as a potential biomarker for disease severity in st-segment elevation myocardial infarction: insights from a university-affiliated cardiovascular center.

MiR-155 plays a role in inflammatory pathways and cardiovascular diseases, though its relationship with inflammation, atherosclerosis, and outcomes in ST-elevation myocardial infarction (STEMI) is not well established. To investigate associations between miR-155 levels, inflammation, atherosclerotic burden, and major adverse cardiovascular events (MACE) in STEMI patients. Sixty-nine STEMI patients and 16 healthy controls were recruited from a specialized university-affiliated cardiovascular center. MiR-155 expression and serum interleukin (IL)-1β, IL-6, and tumor necrosis factor levels were measured. Patients were grouped into tertiles based on miR-155 expression. Clinical data, atherosclerotic burden (through cardiac catheterization), and in-hospital MACE were recorded. MiR-155 levels were significantly lower in STEMI patients compared to controls (median 54.2, vs. 152.8 arbitrary units; p = 0.003). Higher miR-155 tertiles were associated with a greater prevalence of three-vessel occlusion (34% vs. 13% vs. 4%; p = 0.007) and increased incidence of pulmonary edema (13% vs. 0% vs. 0%; p = 0.030). No significant correlation was found between miR-155 and inflammatory or myocardial markers. Dysregulated miR-155 expression in STEMI patients may influence disease severity and MACE risk, independent of inflammation or myocardial damage markers.

MiRNAs and tempol therapeutic potential in prostate cancer: a preclinical approach.

This study investigated tempol action on genes and miRNAs related to NFκB pathway in androgen dependent or independent cell lines and in TRAMP model in the early and late-stages of cancer progression. A bioinformatic search was conducted to select the miRNAs to be measured based on the genes of interest from NFκB pathway. The miR-let-7c-5p, miR-26a-5p and miR-155-5p and five target genes (BCL2, BCL2L1, RELA, TNF, PTGS2) were chosen for RT-PCR and gene enrichment analyses. In vitro, PC-3 and LNCaP cells were exposed, respectively, to 1.0 or 2.0 mM of tempol during 48h. In vivo, five experimental groups were evaluated regarding tempol effects in the early (CT12 and TPL12 groups) and late-stages (CT20, TPL20-I and TLP20-II) of PCa development. TPL groups were treated with 50mg/kg or 100mg/kg of tempol. The ventral lobe of the prostate and the plasma was collected. Tempol treatment increased miRs expression in PC-3 and LNCaP. For both cell lines, tempol decreased RELA expression. In TRAMP model, tempol increased miRNA expression in prostate for all treated groups. Tempol upregulated the miRNA expressions related to the NFκB pathway in the prostate tissue and human tumor cell lines. Their increase is mainly linked to increased cell death and delayed CaP aggressivenes. Thus, tempol's capacity for miRNA-mediated gene silencing to decrease tissue proliferation and cell survival processes is part of its tissue mechanics.

New insights into the interplay between MALAT1 and miRNA-155 to unravel potential diagnostic and prognostic biomarkers of Behçet’s disease

The current study was deployed to evaluate the role of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) and miR-155, along with the inflammatory markers, TNFα and IL-6, and the adhesion molecule, cluster of differentiation 106 (CD106), in Behçet’s disease (BD) pathogenesis. The study also assessed MALAT1/miR-155 as promising diagnostic and prognostic biomarkers for BD. The current retrospective case–control study included 74 Egyptian BD patients and 50 age and sex-matched controls. Blood samples were collected, and then, serum samples were separated for further biochemical and molecular investigations. The gene expression of MALAT1 and miR-155 was measured using qRT-PCR, whereas the levels of TNFα, IL-6, and CD106 were estimated using ELISA technique. MALAT1 was significantly downregulated, whereas miR-155 was upregulated among BD patients, compared with control subjects. Levels of TNFα, IL-6, and CD106 were elevated in BD patients. Further downregulation in MALAT1 together with upregulation of miR-155 was observed in active BD patients, relative to the inactive group. Receiver-operating-characteristic analysis revealed that MALAT1 and miR-155 could discriminate BD patients from controls, on the one hand, and active from inactive BD patients, on the other hand. MALAT1 was negatively correlated with TNFα, IL-6, and CD106, while miR-155 was positively correlated with them. Logistic regression analyses demonstrated miR-155 as a significant independent predictor of BD susceptibility, and MALAT1 as an independent negative predictor of BD activity. For the first time, the current research enlightens the role of MALAT1 and miR-155 in BD pathogenesis via impacting IL-6/TNF-α/CD-106 signaling. As well, MALAT1 and miR-155 could be regarded as novel non-invasive biomarkers that may improve BD diagnosis and prognosis. Key Points•MALAT1/miR-155 exerts potential role in Behçet’s disease.•MALAT1/miR-155 are promising biomarkers for Behçet’s disease.•MALAT1/miR-155 targets IL-6/TNF-α/CD-106 signaling.

Changes in Levels of MiR-21, MiR-27a, MiR-221, and MiR-429 in the Thymus after Photodynamic Therapy and Surgical Treatment of Breast Cancer in Female Wistar Rats.

We studied the expression levels of microRNAs (miR-21, miR-27a, miR-221, and miR-429) in the thymus of female Wistar rats after surgical treatment of breast cancer (BC) and after photodynamic therapy for BC followed by tumor resection. In the group without treatment, the levels of pro-oncogenic miR-21, miR-27a, and miR-221 in the thymus were reduced in comparison with those in the group of intact control. After surgical treatment of BC, the levels of miR-21 and miR-27a in the thymus increased in comparison with those in BC without treatment. Surgical removal of the tumor followed by photodynamic therapy led to an even greater increase in the levels of miR-21 and miR-27a in the thymus in comparison with those in the group of surgical treatment alone. Expression of the tumor-suppressive miR-429 in the thymus significantly exceeds the levels in the BC without treatment and BC+surgery groups.

Role of miR-181 Family Members in Stroke: Insights into Mechanisms and Therapeutic Potential.

Stroke is a major cause of mortality and long-term disability worldwide, making early diagnosis and effective treatment crucial for reducing its impact. In response to the limited efficacy of current treatments, alternative therapeutic strategies, such as novel biomarkers and therapies, are emerging to address this critical unmet medical need. MicroRNAs (miRNAs) are small, non-coding RNAs that regulate gene expression at the post-transcriptional level. Due to their dysregulation, they have been implicated in the onset and progression of various diseases. Recent research highlighted the important role of miR-181 family members in the context of stroke. Polymorphisms such as rs322931 in miR-181b are associated with increased stroke risk. miR-181 family members are aberrantly expressed and related to various aspects of stroke pathology, affecting inflammatory responses or neuronal survival. We provide a comprehensive overview of how alterations in miR-181 expression influence stroke mechanisms and their potential as therapeutic targets.

Agathisflavone Inhibits Viability and Modulates the Expression of miR-125b, miR-155, IL-6, and Arginase in Glioblastoma Cells and Microglia/Macrophage Activation.

Glioblastomas (GBM) are malignant tumours with poor prognosis. Treatment involves chemotherapy and/or radiotherapy; however, there is currently no standard treatment for recurrence, and prognosis remains unfavourable. Inflammatory mediators and microRNAs (miRNAs) influence the aggressiveness of GBM, being involved in the communication with the cells of the tumour parenchyma, including microglia/macrophages, and maintaining an immunosuppressive microenvironment. Hence, the modulation of miRNAs and inflammatory factors may improve GBM treatments. In this study, we investigated the effects of agathisflavone, a biflavonoid purified from Cenostigma pyramidale (Tul.), on the growth and migration of GBM cells, on the expression of inflammatory cytokines and microRNAs, as well on the response of microglia. Agathisflavone (5-30 μM) induced a dose- and time-dependent reduction in the viability of both human GL-15 and rat C6 cells, as determined by the MTT test, and reduced cell migration, as determined by cell scratch assay. RT-qPCR analysis revealed that agathisflavone (5 μM) down-regulated the expression of miR-125b and miR-155 in the secretome derived from GL-15 cells, which was associated with upregulation of the mRNA expression of IL-6 and arginase-1 immunoregulatory factors. Exposure of human microglia/macrophage to the secretome from GL-15 GMB cells modulated proliferation and morphology, effects that were modulated by agathisflavone treatment. These results demonstrate the effect of flavonoids on the growth of GBM cells, which impacts cells in the microenvironment and can be considered for preclinical studies for adjuvant treatments.

Identification of the EBF1/ETS2/KLF2-miR-126-Gene Feed-Forward Loop in Breast Carcinogenesis and Stemness.

MicroRNA (miR)-126 is frequently downregulated in malignancies, including breast cancer (BC). Despite its tumor-suppressive role, the mechanisms underlying miR-126 deregulation in BC remain elusive. Through silencing experiments, we identified Early B Cell Factor 1 (EBF1), ETS Proto-Oncogene 2 (ETS2), and Krüppel-Like Factor 2 (KLF2) as pivotal regulators of miR-126 expression. These transcription factors were found to be downregulated in BC due to epigenetic silencing or a "poised but not transcribed" promoter state, impairing miR-126 expression. Gene Ontology analysis of differentially expressed miR-126 target genes in the Cancer Genome Atlas: Breast Invasive Carcinoma (TCGA-BRCA) cohort revealed their involvement in cancer-related pathways, primarily signal transduction, chromatin remodeling/transcription, and differentiation/development. Furthermore, we defined interconnections among transcription factors, miR-126, and target genes, identifying a potential feed-forward loop (FFL) crucial in maintaining cellular identity and preventing the acquisition of stemness properties associated with cancer progression. Our findings propose that the dysregulation of the EBF1/ETS2/KLF2/miR-126 axis disrupts this FFL, promoting oncogenic transformation and progression in BC. This study provides new insights into the molecular mechanisms of miR-126 downregulation in BC and highlights potential targets for therapeutic intervention. Further research is warranted to clarify the role of this FFL in BC, and to identify novel therapeutic strategies aimed at modulating this network as a whole, rather than targeting individual signals, for cancer management.

Vitamin D modulates the content of inflammatory microRNAs in extracellular vesicles from human adipocyte cells in inflammatory context.

Inflammation of adipose tissue is a contributing factor to many chronic diseases associated with obesity. We previously showed that micronutrients such as vitamin D (VD) limited this metabolic inflammation by decreasing inflammatory markers expression including miR-155 (microRNA-155) or miR-146a in different in vitro and in vivo models. These miRNAs could be incorporated into extracellular vesicles (EVs) in order to modulate the activity of target cells. Nevertheless, the role of VD on the miRNAs contained in EVs from adipose tissue in inflammatory conditions remains unclear. In this study, we used a human model of SGBS (Simpson-Golabi-Behmel syndrome) adipocytes preincubated with 1,25(OH)2D (the active form of VD) before an inflammatory stress with tumor necrosis factor α (TNFα). First, we confirmed by quantitative PCR that the expression of classical inflammatory factors (TNFα and chemokine ligand 2 [CCL2/MCP1]), miR-146a, and miR-155 was increased significantly under inflammatory conditions in SGBS cells and that VD prevented this up-regulation. Secondly, transmission electron microscope imaging of EVs preparations in supernatant allowed visualization of small and large vesicles under these conditions. Then, EVs were obtained with isolation kit and the expression of miR-155 and miR-146a were measured. The expression of miR-155 under TNFα effect was increased in EVs while miR-146a was not detected. Moreover, we also showed that the TNFα-mediated expression of miR-155 in EVs was significantly reduced by a VD pre-incubation of cells. Using miRNA PCR array, we also identified 33 miRNAs, organized in 5 clusters that were differentially regulated by TNFα and VD. Bioinformatic analysis of biological pathways revealed that the different miRNAs targeting genes that are involved in important cell process such as the regulation of transcription or protein phosphorylation. In conclusion, these results support for the first time that VD modulated the expression of miRNAs in EVs from adipocytes, which could represent a new mechanism of regulation of inflammation by micronutrients.