Search results for "miRNA"
showing 10 items of 190 documents
Inducible and reversible inhibition of mirna-mediated gene repression in vivo
2021
Although virtually all gene networks are predicted to be controlled by miRNAs, the contribution of this important layer of gene regulation to tissue homeostasis in adult animals remains unclear. Gain and loss-of-function experiments have provided key insights into the specific function of individual miRNAs, but effective genetic tools to study the functional consequences of global inhibition of miRNA activity in vivo are lacking. Here we report the generation and characterization of a genetically engineered mouse strain in which miRNA-mediated gene repression can be reversibly inhibited without affecting miRNA biogenesis or abundance. We demonstrate the usefulness of this strategy by invest…
Molecular Mediators of RNA Loading into Extracellular Vesicles
2021
In the last decade, an increasing number of studies have demonstrated that non-coding RNA (ncRNAs) cooperate in the gene regulatory networks with other biomolecules, including coding RNAs, DNAs and proteins. Among them, microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) are involved in transcriptional and translation regulation at different levels. Intriguingly, ncRNAs can be packed in vesicles, released in the extracellular space, and finally internalized by receiving cells, thus affecting gene expression also at distance. This review focuses on the mechanisms through which the ncRNAs can be selectively packaged into extracellular vesicles (EVs).
Targeted Therapy Modulates the Secretome of Cancer-Associated Fibroblasts to Induce Resistance in HER2-Positive Breast Cancer
2021
The combination of trastuzumab plus pertuzumab plus docetaxel as a first-line therapy in patients with HER2-positive metastatic breast cancer has provided significant clinical benefits compared to trastuzumab plus docetaxel alone. However, despite the therapeutic success of existing therapies targeting HER2, tumours invariably relapse. Therefore, there is an urgent need to improve our understanding of the mechanisms governing resistance, so that specific therapeutic strategies can be developed to provide improved efficacy. It is well known that the tumour microenvironment (TME) has a significant impact on cancer behaviour. Cancer-associated fibroblasts (CAFs) are essential components of the…
Centenarians maintain miRNA biogenesis pathway while it is impaired in octogenarians.
2016
Centenarians but not octogenarians up regulate the expression of miRNAs, as we previously reported. We have looked into miRNA biogenesis. We show that RNA POL II, DROSHA, EXPORTIN 5 and DICER, are up-regulated in centenarians compared with octogenarians. Furthermore, factors involved in the control of these miRNAs biogenesis genes are also up-regulated in centenarians. Therefore, the up-regulation of miRNA expression in centenarians can be explained in part because miRNA biogenesis pathway is depressed in octogenarians (ordinary aging) while it is maintained in centenarians (extraordinary aging).
Increased serum miR-193a-5p during non-alcoholic fatty liver disease progression: Diagnostic and mechanistic relevance
2022
Background & Aims Serum microRNA (miRNA) levels are known to change in non-alcoholic fatty liver disease (NAFLD) and may serve as useful biomarkers. This study aimed to profile miRNAs comprehensively at all NAFLD stages. Methods We profiled 2,083 serum miRNAs in a discovery cohort (183 cases with NAFLD representing the complete NAFLD spectrum and 10 population controls). miRNA libraries generated by HTG EdgeSeq were sequenced by Illumina NextSeq. Selected serum miRNAs were profiled in 372 additional cases with NAFLD and 15 population controls by quantitative reverse transcriptase PCR. Results Levels of 275 miRNAs differed between cases and population controls. Fewer differences were seen wi…
UPREGULATION OF MIR-29A AND GENOMIC DNA HYPERMETHYLATION IN NORMAL KARYOTYPE AML SHOWING DNMT3A MUTATION UPREGOLAZIONE DEL MIR-29A E IPERMETILAZIONE …
2015
DNMT3A, a member of DNA methyltransferases, is mutated in approximately 22% of de novo normal karyotype acute myeloid leukemia (NK-AML) patients leading to adverse overall survival. The highly recurrent mutation in DNMT3A is a “gain of function-like” at codon R882. To indagate about miRNA signature in NK-AML R882-DNMT3A mutated we studied by qRT-PCR the expression of 384 known human miRNA in 9 selected de-novo AML DNMT3A mutated. We compared miRNA expression data with our previous results obtained in 31 AML DNMT3A wild type (WT) and we focused on a strong up-regulation of miR155, miR29a, miR196b and miR25. We consolidated this data in additional 24 new DNMT3A mutated AML and we confirmed th…
Relazione tra l’espressione del repressore trascrizionale MBP-1 e di miRNAs nel carcinoma mammario
2013
MBP-1 (Myc-promoter-binding-protein-1) è una proteina di 37 kDa, prodotta dalla traduzione alternativa del mRNA del gene ENO1, codificante per l’enzima glicolitico α-enolasi. MBP-1 svolge il ruolo di repressore trascrizionale agendo direttamente sul promotore di c-MYC, ERBB2 e COX2, tutti geni coinvolti in diverse fasi della progressione tumorale (1-3). Nei carcinomi duttali infiltranti della mammella (IDC), l’espressione di MBP-1 è inversamente correlata alla comparsa di metastasi linfonodali e di recidive (4). In diverse linee cellulari tumorali l’overespressione di MBP-1 risulta nella riduzione della proliferazione cellulare e dell’invasività e in un aumento nella morte cellulare per apo…
Upregulation of miR-29a and genomic DNA hypermethylation in normal karyotype AML showing DNMT3A mutation
2015
Acute Myeloid Leukaemia (AML) is frequently associated to normal karyotype and DNMT3A mutations (R882). Since we previously demonstrated distinctive miRNA expression in some AML groups, we study 384 miRNA in 9 selected DNMT3A-mutated NK-AML patients. Comparing these data with our previous results obtained in 31 DNMT3A-unmutated AML, we focused on a significant up-regulation of miR-155, miR-29a, miR-196b and miR-25. We investigated expression of these miRNAs in additional 24 DNMT3A-mutated AML patients and we confirm the up-regulation of miR-155, miR-29a and miR-196b; in particular, we judged very interesting the over expression of miR-29a since is known to directly target DNMT3A, TET1 and T…
Detecting significant features in modeling microRNA-target interactions
2017
MicroRNAs (miRNAs) are small non-coding RNA molecules mediating the translational repression and degradation of target mRNAs in the cell. Mature miRNAs are used as a template by the RNA-induced silencing complex (RISC) to recognize the complementary mRNAs to be regulated. Up to 60% of human genes are putative targets of one or more miRNAs. Several prediction tools are available to suggest putative miRNA targets, however, only a small part of the interaction pairs has been validated by experimental approaches. The analysis of the expression profile of the RNA fraction immunoprecipitated (IP) with the RISC proteins is an established method to detect which genes are actually regulated by the R…