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The miR-15/16 family targets a large network of genes in T cells to restrict their cell cycle, memory formation, and survival. Upon T cell activation, miR-15/16 are downregulated, allowing rapid expansion of differentiated effector T cells to mediate a sustained response. Here, we used conditional deletion of miR-15/16 in regulatory T cells (Tregs) to identify immune functions of the miR-15/16 family in T cells. miR-15/16 are indispensable to maintain peripheral tolerance by securing efficient suppression by a limited number of Tregs. miR-15/16 deficiency alters expression of critical Treg proteins and results in accumulation of functionally impaired FOXP3loCD25loCD127hi Tregs. Excessive proliferation in the absence of miR-15/16 shifts Treg fate and produces an effector Treg phenotype. These Tregs fail to control immune activation, leading to spontaneous multi-organ inflammation and increased allergic inflammation in a mouse model of asthma. Together, our results demonstrate that miR-15/16 expression in Tregs is essential to maintain immune tolerance.

1. In a previous high-throughput sequencing study, a novel circular RNA (circRNA) generated from a SUN domain containing ossification factor (SUCO) gene transcript (circSUCO) was differentially expressed during the embryonic muscle development. This study aimed to further explore the effect of circSUCO on chicken skeletal muscle development. 2. The experiment analysed the expression patterns of circSUCO in Tianfu broilers and clarified its function in the chicken skeletal muscle satellite cells (SMSC) after circSUCO knockdown. The qPCR results showed circSUCO was highly expressed in skeletal muscle and has different expression levels during various development periods. 3. Mechanistically, a series of in vitro experiments showed that circSUCO interference suppressed proliferation and differentiation of SMSC. In addition, it was observed that circSUCO competitively binds with microRNAs such as miR-15a, miR-15b-5p, and miR-15c-5p according to the dual-luciferase assay and qPCR. 4. Correlation was positive between the circSUCO expression level and the ratio of the breast muscle. The results revealed that circSUCO could play a positive role in proliferation and differentiation of SMSC via sponging miR-15a, miR-15b-5p, and miR-15c-5p, hence, may contribute to skeletal muscle development in chicken. [ABSTRACT FROM AUTHOR]

Objective: Osteoarthritis is the most common disease in the group of joint diseases, and its incidence is directly related to aging. Given the anti-inflammatory effects of curcumin as an active ingredient of turmeric, we aimed to investigate the effects of this compound in a new curcumin nanomicelle formula named SinaCurcumin® on the expression of microRNAs (miRNAs) involved in immune responses of patients with osteoarthritis.Materials and Methods: We divided 30 patients with osteoarthritis into two groups namely, nano curcumin-receiving (15 patients) and placebo-receiving (15 patients) and we studied them for 3 months. The Iranian Registry of Clinical Trials (IRCT) approved our study with the IRCT registry No. IRCT20151028024760N4. We evaluated the rates of the expression of microRNAs 146, 155, 16, and 138 employing SYBR Green Real-Time PCR method.Results: The expression of miRNAs 155, 138, and 16 revealed a significant reduction in the curcumin-receiving group (p=0.002, p=0.024 and p=0.0001 respectively).Conclusion: Our research data indicated that the consumption of curcumin in patients with osteoarthritis could affect the immune system partially via altering the expression of microRNAs and cytokines.

Objective: Osteoarthritis is the most common disease in the group of joint diseases, and its incidence is directly related to aging. Given the anti-inflammatory effects of curcumin as an active ingredient of turmeric, we aimed to investigate the effects of this compound in a new curcumin nanomicelle formula named SinaCurcumin® on the expression of microRNAs (miRNAs) involved in immune responses of patients with osteoarthritis. Materials and Methods: We divided 30 patients with osteoarthritis into two groups namely, nano curcumin-receiving (15 patients) and placebo-receiving (15 patients) and we studied them for 3 months. The Iranian Registry of Clinical Trials (IRCT) approved our study with the IRCT registry No. IRCT20151028024760N4. We evaluated the rates of the expression of microRNAs 146, 155, 16, and 138 employing SYBR Green Real-Time PCR method. Results: The expression of miRNAs 155, 138, and 16 revealed a significant reduction in the curcumin-receiving group (p=0.002, p=0.024 and p=0.0001 respectively) Conclusion: Our research data indicated that the consumption of curcumin in patients with osteoarthritis could affect the immune system partially via altering the expression of microRNAs and cytokines. [ABSTRACT FROM AUTHOR]

Abstract Background Accumulating evidence has revealed that circular RNAs (circRNAs), as novel noncoding RNAs, play critical roles in carcinogenesis and tumor progression. However, the functions and molecular mechanisms of circRNAs in clear cell renal cell carcinoma (ccRCC) are largely unknown. Methods The expression and functions of circAGAP1 were identified in clinical samples, ccRCC cells and in vivo animal models. The molecular mechanism of circAGAP1 was investigated by fluorescence in situ hybridization, RNA immunoprecipitation and luciferase assays. Results circAGAP1 (circ0058792) expression was significantly upregulated in ccRCC tissues compared to adjacent nontumor tissues. Moreover, the expression of circAGAP1 was closely related to the tumor size, nuclear grade and clinical stage of ccRCC in patients. Mechanistic studies demonstrated that cytoplasmic circAGAP1 targeted miR-15-5p in an RNA-induced silencing complex. Additionally, miR-15-5p expression was downregulated in ccRCC. Luciferase reporter assays showed that E2F transcription factor 3 (E2F3) was a target of miR-15-5p, and upregulated E2F3 expression was positively correlated with circAGAP1 in ccRCC. Furthermore, the tumor-promoting functions of circAGAP1 could be alleviated by miR-15-5p mimics in vitro and in vivo. Conclusion Our results clarify that circAGAP1 exerts its oncogenic functions as a competitive endogenous RNA (ceRNA) by sponging miR-15-5p, which promotes E2F3 expression. Targeting circAGAP1 might be a new attractive therapeutic strategy in ccRCC.

Abstract Background Viral myocarditis (VMC) is a type of cardiac inflammation that is generally caused by coxsackievirus B3 (CVB3) infection. Several MicroRNAs (miRNAs) are known to play crucial roles in VMC pathogenesis. MiR-15 is reportedly associated with myocardial injury, inflammatory responses and viral infection. Whether miR-15 affects the occurrence and development of VMC remains largely unknown. The roles of miR-15 and their underlying mechanisms in CVB3-stimulated H9c2 cells were assessed in this study. Methods We infected H9c2 cells with CVB3 to establish a VMC cellular model. We then determined the effects of miR-15 inhibition on three cardiomyocyte injury markers: lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB) and cardiac troponin-I (cTn-I). The impact on CVB3-induced cell apoptosis and pro-inflammatory cytokines was also investigated. The effects of miR-15 inhibition on NLRP3 inflammasome activation were also assessed. The target relationship between miR-15 and NOD-like receptor X1 (NLRX1) was determined using a luciferase reporter assay. Results MiR-15 expression was significantly upregulated in H9c2 cells after CVB3 infection. Inhibition of miR-15 significantly decreased the CVB3-induced levels of LDH, CK-MB and cTn-I. It also elevated cell viability, reduced CVB3-induced cell apoptosis and decreased the generation of the interleukins IL-1β, IL-6 and IL-18. Furthermore, we determined that miR-15 inhibition suppressed NLRP3 inflammasome activation by downregulating NLRP3 and caspase-1 p20 expression. We found a direct target relationship between miR-15 and NLRX1. Additionally, inhibition of NLRX1 reversed the protective effects of miR-15 inhibition against CVB3-induced myocardial cell injury by regulating the NLRP3 inflammasome. Conclusion Our results indicate that miR-15 inhibition alleviates CVB3-induced myocardial inflammation and cell injury. This may be partially due to NLRX1-mediated NLRP3 inflammasome inactivation.

MicroRNAs (miRNAs) post‐transcriptionally repress almost all genes in mammals and thereby form an additional layer of gene regulation. As such, miRNAs impact on nearly every physiological process and have also been associated with cancer. Prominent examples of such miRNAs can be found in the miR‐15 family, composed of the bicistronic clusters miR‐15a/16‐1, miR‐15b/16‐2, and miR‐497/195. In particular, the miR‐15a/16‐1 cluster is deleted in almost two thirds of all chronic B lymphocytic leukemia (CLL) cases, a phenotype that is also recapitulated by miR‐15a/16‐1‐deficient as well as miR‐15b/16‐2‐deficient mice. Under physiological conditions, those two clusters have been implicated in T‐cell function, and B‐cell and natural killer (NK) cell development; however, it is unclear whether miR‐497 and miR‐195 confer similar roles in health and disease. Here, we have generated a conditional mouse model for tissue‐specific deletion of miR‐497 and miR‐195. While mice lacking miR‐15a/16‐1 in the hematopoietic compartment developed clear signs of CLL over time, aging mice deficient for miR‐497/195 did not show such a phenotype. Likewise, loss of miR‐15a/16‐1 impaired NK and early B‐cell development, whereas miR‐497/195 was dispensable for these processes. In fact, a detailed analysis of miR‐497/195‐deficient mice did not reveal any effect on steady‐state hematopoiesis or immune cell function. Unexpectedly, even whole‐body deletion of the cluster was well‐tolerated and had no obvious impact on embryonic development or healthy life span. Therefore, we postulate that the miR‐497/195 cluster is redundant to its paralog clusters or that its functional relevance is restricted to certain physiological and pathological conditions. [ABSTRACT FROM AUTHOR]

Background: Accumulating evidence has revealed that circular RNAs (circRNAs), as novel noncoding RNAs, play critical roles in carcinogenesis and tumor progression. However, the functions and molecular mechanisms of circRNAs in clear cell renal cell carcinoma (ccRCC) are largely unknown. Methods: The expression and functions of circAGAP1 were identified in clinical samples, ccRCC cells and in vivo animal models. The molecular mechanism of circAGAP1 was investigated by fluorescence in situ hybridization, RNA immunoprecipitation and luciferase assays. Results: circAGAP1 (circ0058792) expression was significantly upregulated in ccRCC tissues compared to adjacent nontumor tissues. Moreover, the expression of circAGAP1 was closely related to the tumor size, nuclear grade and clinical stage of ccRCC in patients. Mechanistic studies demonstrated that cytoplasmic circAGAP1 targeted miR-15-5p in an RNA-induced silencing complex. Additionally, miR-15-5p expression was downregulated in ccRCC. Luciferase reporter assays showed that E2F transcription factor 3 (E2F3) was a target of miR-15-5p, and upregulated E2F3 expression was positively correlated with circAGAP1 in ccRCC. Furthermore, the tumor-promoting functions of circAGAP1 could be alleviated by miR-15-5p mimics in vitro and in vivo. Conclusion: Our results clarify that circAGAP1 exerts its oncogenic functions as a competitive endogenous RNA (ceRNA) by sponging miR-15-5p, which promotes E2F3 expression. Targeting circAGAP1 might be a new attractive therapeutic strategy in ccRCC. [ABSTRACT FROM AUTHOR]

The miR-15/107 group of microRNAs (miRNAs) encloses 10 annotated human members and is defined based on the presence of the sequence AGCAGC near the mature miRNAs’ 5′ end. Members of the miR-15/107 group expressed in humans are highly evolutionarily conserved, and seven of these miRNAs are widespread in vertebrate species. Contrary to the majority of miRNAs, which recognize complementary sequences on the 3′UTR region, some members of the miR-15/107 group are peculiarly characterized by the ability to target the coding sequence (CDS) of their target mRNAs, inhibiting translation without strongly affecting their mRNA levels. There is compelling evidence that different members of the miR-15/107 group regulate overlapping lists of mRNA targets but also show target specificity. The ubiquitously expressed miR-15/107 gene group controls several human cellular pathways, such as proliferation, angiogenesis, and lipid metabolism, and might be altered in various diseases, such as neurodegenerative diseases and cancer. Intriguingly, despite sharing the same seed sequence, different members of this family of miRNAs may behave as oncomiRs or as tumor suppressor miRNAs in the context of cancer cells. This review discusses the regulation and functional contribution of the miR-15/107 group to the control of gene expression. Moreover, we particularly focus on the contribution of specific miR-15/107 group members as tumor suppressors in breast cancer, reviewing literature reporting their ability to function as major controllers of a variety of cell pathways and to act as powerful biomarkers in this disease.

Neonatal pneumonia is a high neonatal mortality disease. We studied the function and mechanism of long noncoding RNA myocardial infarction‐associated transcript 2 (lncRNA MIAT2) on lipopolysaccharide (LPS)‐induced inflammation in WI‐38 cells. Cell Counting Kit‐8 and apoptosis assay were respectively used to detect the functions of LPS, MIAT2, and microRNA‐15 (miR‐15) on viability and apoptosis. MIAT2 and miR‐15 expressions were changed by cell transfection. Moreover, reverse transcription‐quantitative polymerase chain reaction (RT‐qPCR), western blot, and enzyme‐linked immunosorbent assay were used to detect the expressions of interleukin (IL)‐6 and monocyte chemoattractant protein‐1 (MCP‐1). The levels of Bax, cleaved‐caspase‐3, and cell pathways‐related proteins were tested by western blot. Besides, the levels of miR‐15 and MIAT2 were tested by RT‐qPCR. We found that LPS declined cell viability and heightened apoptosis and levels of Bax, cleaved‐caspase‐3, IL‐6, and MCP‐1. MIAT2 was negatively regulated by LPS and it alleviated LPS‐induced damage. Furthermore, MIAT2 reversely regulated miR‐15 and miR‐15 mimic could reverse the effects of MIAT2. Finally, MIAT2 restrained the p38MAPK and NF‐κB pathways by downregulating miR‐15. In conclusion, MIAT2 alleviated LPS‐induced inflammation damage in WI‐38 cells by sponging miR‐15 via p38MAPK and NF‐κB pathways. [ABSTRACT FROM AUTHOR]

Background: Viral myocarditis (VMC) is a type of cardiac inflammation that is generally caused by coxsackievirus B3 (CVB3) infection. Several MicroRNAs (miRNAs) are known to play crucial roles in VMC pathogenesis. MiR-15 is reportedly associated with myocardial injury, inflammatory responses and viral infection. Whether miR-15 affects the occurrence and development of VMC remains largely unknown. The roles of miR-15 and their underlying mechanisms in CVB3-stimulated H9c2 cells were assessed in this study. Methods: We infected H9c2 cells with CVB3 to establish a VMC cellular model. We then determined the effects of miR-15 inhibition on three cardiomyocyte injury markers: lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB) and cardiac troponin-I (cTn-I). The impact on CVB3-induced cell apoptosis and pro-inflammatory cytokines was also investigated. The effects of miR-15 inhibition on NLRP3 inflammasome activation were also assessed. The target relationship between miR-15 and NOD-like receptor X1 (NLRX1) was determined using a luciferase reporter assay. Results: MiR-15 expression was significantly upregulated in H9c2 cells after CVB3 infection. Inhibition of miR-15 significantly decreased the CVB3-induced levels of LDH, CK-MB and cTn-I. It also elevated cell viability, reduced CVB3-induced cell apoptosis and decreased the generation of the interleukins IL-1β, IL-6 and IL-18. Furthermore, we determined that miR-15 inhibition suppressed NLRP3 inflammasome activation by downregulating NLRP3 and caspase-1 p20 expression. We found a direct target relationship between miR-15 and NLRX1. Additionally, inhibition of NLRX1 reversed the protective effects of miR-15 inhibition against CVB3-induced myocardial cell injury by regulating the NLRP3 inflammasome. Conclusion: Our results indicate that miR-15 inhibition alleviates CVB3-induced myocardial inflammation and cell injury. This may be partially due to NLRX1-mediated NLRP3 inflammasome inactivation. [ABSTRACT FROM AUTHOR]

تمرین هوازی، رشد تومور سرطان پستان را کاهش می‌دهد. پژوهش حاضر، تغییر بیان ژن miR-15 و BcL2 و پروتئین BcL2 را به‌عنوان سازوکارهای مثبت ناشی از تمرین هوازی در سرطان پستان مورد‌بررسی قرار داده است. بدین‌منظور، ‌20 سر موش بالب 30 ماده (پنج تا شش هفته‌ای‌ با میانگین تودۀ بدنی 17ـ16 گرم) با تزریق سلول‌های سرطانی MC4-L2‌ به سرطان مبتلا شدند. سپس، به‌صورت تصادفی به دو گروه 10 نفری تمرین و کنترل تقسیم گردیدند. در ادامه و 48 ساعت پس از آخرین جلسۀ تمرین، قربانی گشتند و نمونه‌های ‌بافتی آن‌ها برداشته شد و در دمای 70- درجه ذخیره گردید. شایان‌ذکر است که میزان بیان miR-15 و BcL2 بافت تومور به روش ریل تایم –پی‌سی‌‌ار و میزان بیان پروتئین BcL2 با استفاده از روشالایزا اندازه‌گیری شد. نتایج نشان می‌دهد که بیان ژن و پروتئین BcL2 و نسبت رشد تومور، به‌شکل معناداری (0.001>P) در گروه تمرین در‌مقایسه با گروه کنترل کاهش یافته است و بیان miR-15 در گروه تمرین، افزایش معناداری را در‌مقایسه با گروه کنترل نشان می‌دهد (0.001>P). در‌مجموع، به‌نظر می‌رسد افزایش بیان ژن miR-15 و کاهش بیان ژن و پروتئین BcL2‌ ناشی از تمرین هوازی، در کاهش نسبت رشد تومور در گروه تمرین مؤثر بوده است.

OBJECTIVE: To investigate the role of microRNA-15 (miR-15) in the progression of bladder cancer (BC) cell and its underlying mechanism. PATIENTS AND METHODS: Human BC specimens were collected from BC patients during operations. BC cell lines (T24, BIU87, and HT1376) and normal uroepithelial cell lines SVHUV-1 were cultured. The abilities of cell proliferation and invasion were detected by Methyl thiazolyl tetrazolium (MTT) and transwell assay, respectively. Additionally, the relevant mRNA and protein expressions were measured by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR), Western blot and immunohistochemistry, respectively. Furthermore, the luciferase reporter assay was used to verify the target gene of miR-15. Besides, Xenograft tumor formation assay was performed to confirm the effect of miR-15 on tumor growth. RESULTS: A low expression of miR-15 was detected by qRT-PCR, whereas the high expression of B cell-specific Moloney murine leukemia virus integration site 1 (BMI1) was detected by immunocytochemical assay in BC tissues. Moreover, miR-15 expression and BMI1 expression were significantly associated with the overall survival of BC patients. MTT and transwell assay results stated that the up-regulation of miR-15 inhibited BC cell proliferation, migration, and invasion. BMI-1 was verified as a direct target of miR-15 in BC using Luciferase reporter assay. Besides, miR-15 regulated epithelial-mesenchymal transition (EMT)-related makers, protein kinase B (AKT), and the phosphorylation of AKT protein levels in BC using the Western blot assay. Xenograft tumor formation assay indicated that the over-expression of miR-15 inhibited the tumor growth. CONCLUSIONS: We stated that miR-15 suppressed BC cell progression by targeting BMI1 through the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway, which provided a potential target for BC treatment. [ABSTRACT FROM AUTHOR]

BACKGROUND: Some studies have shown that CD133 is a stem cell marker for a variety of tumor cells, such as pancreatic cancer, which is associated with a poor prognosis in cancer patients. miR-15 family is involved in cell apoptosis, differentiation, cycle regulation and stress, and has potential value as an intervention. OBJECTIVE: To investigate the effects of miR-15 family on the migration and invasion of CD133+ pancreatic cancer stem-like cells. METHODS: First, a highly migrating pancreatic cancer cell line, Capan-1M9, was constructed, and then CD133+Capan-1M9 cell lines that overexpressed miR-15a, miR-15b and miR-15c were constructed by lentivirus transduction. NC-miRNA cell lines were taken as negative controls. Expression of miR-15a, miR-15b and miR-15c in the recombinant cell lines and epithelial-mesenchymal transition (EMT)-related proteins, fibronectin, vimentin and N-cadherin mRNA were determined by qRT-PCR. MTT assay was used to detect the proliferation and gemcitabine resistance of recombinant cell lines. Spheroid formation test was used to detect the self-renewal ability of recombinant cell lines. Migration and invasion ability of the recombinant cell lines were detected by cell migration and invasion assay. EMT-related proteins fibronectin, vimentin and N-cadherin were detected by western blot. RESULTS AND CONCLUSION: qPCR results showed that the expression of miR-15a, miR-15b and miR-15c in the CD133+ Capan-1M9 cell lines increased by 8.3, 10 and 9.5 times compared with the negative control group, and the expression of fibronectin, vimentin and N-cadherin mRNA was also significantly increased (P < 0.05). There was no significant difference in cell proliferation between the recombinant cell lines and the negative control group (P > 0.05), but the gemcitabine resistance was significantly increased in the recombinant cell lines as detected by the MTT (P < 0.05). The number and volume of spheres in the recombinant cell lines did not change significantly compared with the negative control group (P > 0.05). The cell migration and invasion abilities of the recombinant cell line were significantly enhanced compared with the negative control group (P < 0.05). Our experimental findings suggest that the miR-15 family can promote migration and invasion of CD133+ pancreatic cancer stem-like cells via EMT regulation. [ABSTRACT FROM AUTHOR]

Overview MicroRNAs (miRNAs) have been implicated in neurodegenerative diseases including Parkinson’s disease and Alzheimer’s disease (AD). Here, we evaluated the expression of miRNAs in anterior cingulate (AC; Brodmann area [BA] 24) and primary motor (MO; BA 4) cortical tissue from aged human brains in the University of Kentucky AD Center autopsy cohort, with a focus on dementia with Lewy bodies (DLB). Methods RNA was isolated from gray matter of brain samples with pathology-defined DLB, AD, AD + DLB, and low-pathology controls, with n = 52 cases initially included (n  = 23 with DLB), all with low (<4 h) postmortem intervals. RNA was profiled using Exiqon miRNA microarrays. Quantitative PCR for post hoc replication was performed on separate cases (n = 6 controls) and included RNA isolated from gray matter of MO, AC, primary somatosensory (BA 3), and dorsolateral prefrontal (BA 9) cortical regions. Results The miRNA expression patterns differed substantially according to anatomic location: of the relatively highly-expressed miRNAs, 150/481 (31%) showed expression that was different between AC versus MO (at p < .05 following correction for multiple comparisons), most (79%) with higher expression in MO. A subset of these results were confirmed in qPCR validation focusing on miR-7, miR-153, miR-133b, miR-137, and miR-34a. No significant variation in miRNA expression was detected in association with either neuropathology or sex after correction for multiple comparisons. Conclusion A subset of miRNAs (some previously associated with α-synucleinopathy and/or directly targeting α-synuclein mRNA) were differentially expressed in AC and MO, which may help explain why these brain regions show differences in vulnerability to Lewy body pathology. [ABSTRACT FROM AUTHOR]

The miR-15/107 family comprises a group of 10 paralogous microRNAs (miRNAs), sharing a 5′ AGCAGC sequence. These miRNAs have overlapping targets. In order to characterize the expression of miR-15/107 family miRNAs, we employed customized TaqMan Low-Density micro-fluid PCR-array to investigate the expression of miR-15/107 family members, and other selected miRNAs, in 11 human tissues obtained at autopsy including the cerebral cortex, frontal cortex, primary visual cortex, thalamus, heart, lung, liver, kidney, spleen, stomach and skeletal muscle. miR-103, miR-195 and miR-497 were expressed at similar levels across various tissues, whereas miR-107 is enriched in brain samples. We also examined the expression patterns of evolutionarily conserved miR-15/107 miRNAs in three distinct primary rat brain cell preparations (enriched for cortical neurons, astrocytes and microglia, respectively). In primary cultures of rat brain cells, several members of the miR-15/107 family are enriched in neurons compared to other cell types in the central nervous system (CNS). In addition to mature miRNAs, we also examined the expression of precursors (pri-miRNAs). Our data suggested a generally poor correlation between the expression of mature miRNAs and their precursors. In summary, we provide a detailed study of the tissue and cell type-specific expression profile of this highly expressed and phylogenetically conserved family of miRNA genes.

Precursor B lymphocytes expand upon expression of a pre-B cell receptor (pre- BCR), but then transit into a resting state in which immunoglobulin light chain gene recombination is initiated. This bi-phasic sequence is orchestrated by the IL-7 receptor ( IL-7R) and pre- BCR signaling, respectively, but little is known about micro RNAs fine-tuning these events. Here, we show that pre-B cells lacking miR-15 family functions exhibit prolonged proliferation due to aberrant expression of the target genes cyclin E1 and D3. As a consequence, they fail to trigger the transcriptional reprogramming normally accompanying their differentiation, resulting in a developmental block at the pre-B cell stage. Intriguingly, our data indicate that the miR-15 family is suppressed by both IL-7R and pre- BCR signaling, suggesting it is actively integrated into the regulatory circuits of developing B cells. These findings identify the miR-15 family as a novel element required to promote the switch from pre-B cell proliferation to differentiation. [ABSTRACT FROM AUTHOR]

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has had a tremendous impact worldwide. Mapping virus-host interactions is critical to understand disease progression. MicroRNAs (miRNAs) are important RNA regulators, but their interaction with SARS-CoV-2 RNA was not experimentally investigated. Here, using Argonaute (AGO) cross-linking immunoprecipitation combined with RNA proximity ligation (CLEAR-CLIP), we provide unbiased mapping of SARS-CoV-2/miRNA interactions. We identified six main regions on the viral RNA bound primarily by one specific miRNA. Targeted mutagenesis and AGO1-3 knockdown demonstrated that these interactions are not critical for virus production. Moreover, we identified perturbed regulation of cellular miRNA interactions during infection, including non-compensated viral sequestration of the miR-15 family. Transcriptome analysis further showed that mRNAs targeted by this miRNA family are derepressed. This work delineates the interphase between miRNA regulation and SARS-CoV-2 infection and further contributes to deciphering the full molecular interactome of this virus. [Display omitted] • Experimental characterization of the microRNA-binding landscape of SARS-CoV-2 RNA • microRNA binding has limited effect on SARS-CoV-2 infection • SARS-CoV-2 affects the cellular microRNA interactome • miR-15 family mRNA targets are derepressed during SARS-CoV-2 infection microRNAs are important post-transcriptional gene regulators hijacked by viruses. Here, Fossat et al. map the microRNA-binding landscape for SARS-CoV-2 RNA. Mutagenesis of the main binding sites and Argonaute silencing show that microRNAs are not critical for replication. However, the cellular microRNA interactome is perturbed during infection, specifically with derepression of miR-15 family targets. [ABSTRACT FROM AUTHOR]

Background MicroRNAs are small non-coding RNAs that regulate post-transcriptional mRNA expression by binding to 3′ untranslated region (3′-UTR) of the complementary mRNA sequence resulting in translational repression and gene silencing. They act as negative regulators of gene expression and play a pivotal role in regulating apoptosis and cell proliferation. Studies have shown that miRNAs interact with p53 by regulating the activity and function of p53 through direct repression or its regulators. Mammalian target of rapamycin (mTOR) is an evolutionary conserved check point protein kinase that plays a major effect in the control of cell division via protein synthesis regulation. mTOR regulates protein synthesis through phosphorylation and inactivation of 4E-BP1 and through phosphorylation and activation of S6 kinase 1 (S6K1). These two downstream effectors of mTOR control cell growth and metabolism. In mammals, mTOR protein kinase is the central node in the nutrient and growth factor signaling and p53 plays a critical role in sensing genotoxic stress. Activation of p53 inhibits mTOR activity, which in turn regulates its downstream targets providing a cross talk among both the signaling machinery. MicroRNA-15 and 16 belong to a common precursor family and are highly conserved. Deletion or downregulation of these two microRNAs has been shown to accelerate cell division by modulating the expression of the genes involved in controlling cell cycle progression. These microRNAs may function as tumor suppressors and act on the downstream targets of p53 signaling pathway. To have a better insight of the role of miR-15/16 in regulating the cross talk of p53 and mTOR, we performed an in depth study in MDA-MB-231 breast cancer cells by performing a gain-of-function analysis with lentiviral plasmids expressing microRNA-15 and 16. Methods The effect of individual microRNAs on RPS6KB1 was examined by using 3′-UTR clones via luciferase based assays. The cell cycle effects were observed by flow-cytometric analysis. Reverse transcription PCR was used to explore the expression of mTOR and RPS6KB1 in cells transfected with miR-15/16. Results Overexpression of miR-15/16 led to inhibition of cell proliferation causing G1 cell cycle arrest as well as caspase-3 dependent apoptosis. Forced expression of miR-15/16 might lead to decrease in mRNA level of RPS6KB1, mTOR. The effect was a complete reversal after treatment with anti-miRs against miR-15/16 proving the specificity of the expression. In addition, the dual luciferase reporter assays indicated a clear decrease in luciferase gene expression in cells transfected with lentiviral based miR-15 and 16 plasmids indicating that miR-15/16 directly targets RPS6KB1 through its 3′-UTR binding. Further, these microRNAs also inhibit epithelial to mesenchymal transition (EMT) by targeting key proteins such as Twist1 and EZH2 clearly demonstrating its crucial role in controlling cell proliferation. Conclusion This study suggests that exogenous microRNA-15/16 can target RPS6KB1, control cell proliferation and cause apoptosis in caspase-dependent manner even in the absence of functional p53. [ABSTRACT FROM AUTHOR]

The proliferation of new techniques that allow a multiparametric study of gene expression, the mutational state of genomic DNA, DNA methylation and the phosphorylation of receptor and adaptor proteins has led to an increased understanding of the origin of different cancers, the definition of new prognosis markers and the response to treatment profiles. Gene profiling studies on chronic lymphocytic leukaemia (CLL) are at the origin of new prognosis markers such as zeta-associated protein-70 (ZAP-70), LPL and CLLU1, which, at present, are under study for their application to clinical practice. An increased resolution in the mutational state at genomic level has underscored the importance of deletion 13q14 at the origin of CLL and 13q and 17p in response to treatment. Some new insights regarding changes in gene expression in CLL cells depending on the microenvironment have been described, but more work is yet to be done in the field. [Copyright &y& Elsevier]

The general basis of cancer is the loss of cell identity and inappropriate proliferation of cells. Classically, a universal paradigm in oncogenesis is the accumulation of mutations in the open reading frames of protein-encoding oncogenes and tumor suppressors. The identification of new classes of noncoding RNAs (ncRNA) important for development and cell homeostasis will likely change this current paradigm. Recent data suggests that a special class of ncRNAs called microRNAs might be involved in human disease. This review proposes a role for microRNAs in oncogenesis. [Copyright &y& Elsevier]

Cognitive impairment (CI) is a frequent complication affecting people with multiple sclerosis (MS). The causes of CI in MS are not fully understood. Besides MRI measures, few other biomarkers exist to help us predict the development of CI and understand its biology. MicroRNAs (miRs) are relatively stable, non-coding RNA molecules about 22 nucleotides in length that can serve as biomarkers and possible therapeutic targets in several autoimmune and neurodegenerative diseases, including the dementias. In this review, we identify dysregulated miRs in MS that overlap with dysregulated miRs in cognitive disorders and dementia and explore how these overlapping miRs play a role in CI in MS. MiR-15, miR-21, miR-128, miR-132, miR-138, miR-142, miR-146a, miR-155, miR-181, miR-572, and let-7 are known to contribute to various forms of dementia and show abnormal expression in MS. These overlapping miRs are involved in pathways related to apoptosis, neuroinflammation, glutamate toxicity, astrocyte activation, microglial burst activity, synaptic dysfunction, and remyelination. The mechanisms of action suggest that these miRs may be related to CI in MS. From our review, we also delineated miRs that could be neuroprotective in MS, namely miR-23a, miR-219, miR-214, and miR-22. Further studies can help clarify if these miRs are responsible for CI in MS, leading to potential therapeutic targets. • Review of dysregulated miRs that overlap in MS and dementias. • Review neuropathological mechanisms involving the proteins targets of the dysregulated miRs. • Review pharmaceutical treatments that alter levels of the above miRs are listed. [ABSTRACT FROM AUTHOR]

The miR-15/107 group of microRNAs (miRNAs) encloses 10 annotated human members and is defined based on the presence of the sequence AGCAGC near the mature miRNAs' 5' end. Members of the miR-15/107 group expressed in humans are highly evolutionarily conserved, and seven of these miRNAs are widespread in vertebrate species. Contrary to the majority of miRNAs, which recognize complementary sequences on the 3'UTR region, some members of the miR-15/107 group are peculiarly characterized by the ability to target the coding sequence (CDS) of their target mRNAs, inhibiting translation without strongly affecting their mRNA levels. There is compelling evidence that different members of the miR-15/107 group regulate overlapping lists of mRNA targets but also show target specificity. The ubiquitously expressed miR-15/107 gene group controls several human cellular pathways, such as proliferation, angiogenesis, and lipid metabolism, and might be altered in various diseases, such as neurodegenerative diseases and cancer. Intriguingly, despite sharing the same seed sequence, different members of this family of miRNAs may behave as oncomiRs or as tumor suppressor miRNAs in the context of cancer cells. This review discusses the regulation and functional contribution of the miR-15/107 group to the control of gene expression. Moreover, we particularly focus on the contribution of specific miR-15/107 group members as tumor suppressors in breast cancer, reviewing literature reporting their ability to function as major controllers of a variety of cell pathways and to act as powerful biomarkers in this disease., (Copyright © 2020 Turco, Donzelli and Fontemaggi.)

Diabetic nephropathy (DN) is an increasing threat to human health and is regarded as an important public issue. The pathophysiologic mechanisms of DN are complicated. The initiating molecular events triggering the loss function in mesangial cells (MCs) in DN are not well known. In this cross-disciplinary study, transcriptome analysis of high glucose (HG)-treated mouse MCs (MMCs) using next-generation sequencing and systematic bioinformatics analyses indicated that miR-15b-5p and its downstream target B cell lymphoma 2 (BCL-2) contribute to HG-induced apoptosis in MMCs. HG elevated miR-15b-5p expression, which in turn decreased the translation of BCL-2, leading to MMC apoptosis under HG. Apoptosis of MCs was enhanced in the presence of extracellular vesicles isolated from the urine of type 2 diabetic patients with high levels of miR-15b-5p. Furthermore, increased levels of urinary miR-15b-5p were found in db/db mice and type 2 diabetic patients, and such levels correlated with low baseline kidney function and rapid decline in kidney function during a mean of follow-up period of 2.4 ± 0.1 years. Therefore, miR-15b-5p induced mesangial cells apoptosis by targeting BCL-2 under HG. miR-15b-5p has the potential to predict kidney injury in DN. Blocking the miR-15b-5p epigenetic regulatory network could be a potential therapeutic strategy to prevent mesangial apoptosis in DN., (Copyright © 2020 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.)

Bedsore is a familiar disease, which fearfully harms the health of the patients. We investigated the efficacy and mechanism of circular RNA circANKRD36 on HaCaT cell in inflammatory damage. CCK-8 and flow cytometry were respectively used to investigate the efficacies of lipopolysaccharide (LPS), circANKRD36, and microRNA (miR)-15 on cell viability and apoptosis. Moreover, circANKRD36 and miR-15 expression were changed by cell transfection and investigated by reverse transcription-quantitative polymerase chain reaction. Furthermore, the levels of Bax, pro caspase-3, cleaved caspase-3, interleukin (IL)-1β, IL-6, and proteins of the pathway were investigated by Western blot. Otherwise, the levels of IL-1β and IL-6 were investigated by enzyme-linked immunosorbent assay. Reactive oxygen species (ROS) was investigated by ROS assay. The relation between myeloid differentiation factor 88 (MyD88) and miR-15 was investigated by luciferase assay. LPS caused inflammatory damage and upregulated circANKRD36. circANKRD36 was silenced in cells and si-circANKRD36 remitted inflammatory damage. Furthermore, si-circANKRD36 negatively regulated miR-15 and miR-15 inhibitor could reverse the efficacies of si-circANKRD36. Besides, si-circANKRD36 restrained the NF-κB pathway by upregulating miR-15. Finally, MyD88 was authenticated as a target of miR-15. circANKRD36 remitted cell inflammatory damage upregulating miR-15/MyD88 via the NF-κB pathway in HaCaT cells., (© 2019 Wiley Periodicals, Inc.)

Objective: MiR-15 is involved in modulating many cellular processes that are normally destroyed in disease. The regulation of the cell cycle, angiogenesis, and responses to cellular stress are notable processes influenced by MiR-15. MiR-15 plays a critical role in the model of inflammation-related angiogenesis defects. However, its role in rheumatoid arthritis (RA) remains unclear. In this paper, we questioned the potential effects miR-15 has on RA., Methods: Synthetic mimics of miR-15 were transfected into human RA fibroblast-like synoviocyte (FLS) cell line MH7A cells. Cell proliferation was detected by a Cell Counting Kit-8 (CCK-8) assay. Cell apoptosis was determined by flow cytometry. MH7A cells, stimulated by interleukin-1β (IL-1β), were transfected with miR-15 mimics and inhibitors. Western blot and quantitative real time (qRT)-PCR were used to detect gene and protein expressions. Bioinformatic software analysis and luciferase reporter assays were used to predict and validate miR-15 targets., Results: We found that the miR-15 experienced down-regulated expression in MH7A cells, after they were stimulated with IL-1β. MiR-15 inhibited inflammatory cell proliferation and promoted inflammatory cell apoptosis. BCL2L2 was identified as a target of miR-15 by luciferase assay. Additionally, NF-κB signaling pathway related proteins were inhibited by miR-15 overexpression., Conclusion: These findings contribute to an understanding of the impact that miR-15 possesses on inflammatory injury, and provide a basis for RA treatment., (© 2019 by the Association of Clinical Scientists, Inc.)

Here, we present a miR mechanism which is active in the nucleus and is essential for the production of intron included, C-terminal truncated and biologically active proteins, like e.g. Vim3. We exemplified this mechanism by miRs, miR-15a and miR-498, which are overexpressed in clear cell renal carcinoma or oncocytoma. Both miRs directly interact with DNA in an intronic region, leading to transcriptional stop, and therefore repress the full length version of the pre-mRNA, resulting in intron included truncated proteins (Mxi-2 and Vim3). A computational survey shows that this miR:DNA interactions mechanism may be generally involved in regulating the human transcriptome, with putative interaction sites in intronic regions for over 1000 genes. In this work, an entirely new mechanism is revealed how miRs can repress full length protein translation, resulting in C-terminal truncated proteins., Competing Interests: CONFLICTS OF INTEREST The authors declare no conflicts of interest.