Project description:The discovery of either missense mutations or amplification of ALK (Anaplastic Lymphoma Kinase) gene identified this receptor tyrosine kinase as a therapeutic target in neuroblastoma (NB). Moreover, a high ALK expression has been associated with cases of metastatic NB and with a worse prognosis. In order to identify miRNAs involved in the regulation of ALK expression in NB we therefore analyzed their expression profile in 16 NB cell lines and in 22 patients by qPCR. We then identified miRNAs which were differentially expressed between two groups of samples showing high (ALK+) or low (ALK-) expression levels of ALK by using microarrays containing 866 human miRNA probes (Agilent). Next, the differential expression analysis between the two groups (ALK+ and ALK-) was performed using R. Our analysis showed a higher expression of 30 and 23 miRNAs (p-value <0.05) in NB lines and samples, respectively, both belonging to the ALK- group. Validation analysis and filtering according to in silico suggested miR-424-5p as a potential ALK regulator candidate. Dual luciferase assay indicated a direct binding of this miRNA to ALK-3’UTR. Moreover, we observed a down-regulation of ALK protein expression following transfection of miR-424-5p mimic as well as inhibition of cell viability in ALK+ NB cell lines. In conclusion, our data suggest miR-424-5p as involved in the regulation of ALK expression in NB.
Project description:The discovery of either missense mutations or amplification of ALK (Anaplastic Lymphoma Kinase) gene identified this receptor tyrosine kinase as a therapeutic target in neuroblastoma (NB). Moreover, a high ALK expression has been associated with cases of metastatic NB and with a worse prognosis. In order to identify miRNAs involved in the regulation of ALK expression in NB we therefore analyzed their expression profile in 16 NB cell lines and in 22 patients by qPCR. We then identified miRNAs which were differentially expressed between two groups of samples showing high (ALK+) or low (ALK-) expression levels of ALK by using microarrays containing 866 human miRNA probes (Agilent). Next, the differential expression analysis between the two groups (ALK+ and ALK-) was performed using R. Our analysis showed a higher expression of 30 and 23 miRNAs (p-value <0.05) in NB lines and samples, respectively, both belonging to the ALK- group. Validation analysis and filtering according to in silico suggested miR-424-5p as a potential ALK regulator candidate. Dual luciferase assay indicated a direct binding of this miRNA to ALK-3’UTR. Moreover, we observed a down-regulation of ALK protein expression following transfection of miR-424-5p mimic as well as inhibition of cell viability in ALK+ NB cell lines. In conclusion, our data suggest miR-424-5p as involved in the regulation of ALK expression in NB.
Project description:TGF-β family ligands are key regulators of dendritic cell (DC) differentiation and activation. Epidermal Langerhans cells (LCs) require TGF-β family signaling for their differentiation and canonical TGF-β1 signaling secures a non-activated LC state. LCs reportedly control skin inflammation and are replenished from peripheral blood monocytes, which also give rise to pro-inflammatory monocyte-derived DCs (moDCs). By studying mechanisms in inflammation, we previously screened LCs vs moDCs for differentially expressed miRNAs. miR-424/503 was the most strongly inversely regulated (moDCs > LCs). We found that miR-424/503 is induced during moDC differentiation and promotes moDC differentiation in human and mouse. Inversely, forced repression of miR-424 during moDC differentiation facilitated TGF-β1-dependent LC differentiation. Mechanistically, miR-424/503 deficiency in monocyte/DC precursors leads to the induction of TGF-β1-response genes critical for LC differentiation. Therefore, the miR-424/503 gene cluster plays a decisive role in anti-inflammatory LC vs pro-inflammatory moDC differentiation from monocytes.
Project description:The H19X-encoded miR-424(322)/503 cluster regulates multiple cellular functions. Here we report for the first time that it is also a critical linchpin of fat mass expansion. Deletion of this miRNA cluster in mice results in obesity, while increasing the pool of early adipocyte progenitors and hypertrophied adipocytes. Complementary loss and gain of function experiments and RNA sequencing demonstrate that miR-424(322)/503 regulates a conserved genetic program involved in the differentiation and commitment of white adipocytes. Mechanistically, we demonstrate that miR-424(322)/503 targets γ-Synuclein (SNCG), a factor that mediates this program rearrangement by controlling metabolic functions in fat cells, allowing adipocyte differentiation and adipose tissue enlargement. Accordingly, diminished miR-424(322) in mice and obese humans co-segregates with increased SNCG in fat and peripheral blood as mutually exclusive features of obesity, being normalized upon weight loss. Our data unveil a previously unknown regulatory mechanism of fat mass expansion tightly controlled by the miR-424(322)/503 through SNCG.
Project description:ALK is a tyrosine kinase receptor and oncogene in neuroblastoma (NB). The receptor is activated by the ALKAL2 ligand, but it is unknown whether missregulation of this ligand may play a role in NB carcinogenesis. Here, a TH-MYCN driven neuroblastoma mice was created +/- ALK F1178S mutation and +/- ALKAL2 overexpression
Project description:ALK is driving neuroblastoma (NB) and RET has been shown to be a downstream target of ALK signaling in NB. To get a better understanding of the role of RET in NB, the gene was knocked out in SKNAS cell lines.
Project description:To explore the variation of serum microRNA expression during osteoporosis, we have employed microRNA microarray expression profiling as a discovery platform to identify microRNAs with the potential to diagnose osteoporosis from healthy and osteopenia individuals for clinical use. Whole blood from healthy, osteopenic and osteoporotic donors was collected, and the sera were separated. Twenty two microRNAs (miR-15a-5p, miR-29b-5p, miR-30c-2-3p, miR-145-5p, miR-199a-5p, miR-301a-3p, miR-424-5p, miR-497-5p, miR-526b-5p, miR-550a-5p, miR-575, miR-654-5p, miR-663a, miR-708-5p, miR-877-3p, miR-1246, miR-1260b, miR-1299, miR-1323, miR-4447, miR-4769-3p and miR-5685) were finally used for further detection of osteoporosis diagnosis.
Project description:Anaplastic Lymphoma Kinase (ALK) most frequently mutated in neuroblastoma (NB) and is atractive molecular target for therapy. However, efficacy of the ALK inhibitor against ALK-amplified NB is unclear. To elucidate genetic alterations induced by treatment of the ALK inhibitor, we compared expression profile between ALK inhibitor-treated and DMSO-treated NB39nu cells using Agilent SurePrint G3 Human GE 8x60K V2 Microarray Kit