LncRNA DLX6-AS1 Promotes the Progression of Neuroblastoma by Activating STAT2 via Targeting miR-506-3p.

BACKGROUND: Neuroblastoma (NB) is a common malignant tumor of the sympathetic nervous system, mainly disturbing children. Long non-coding RNAs (lncRNAs) serving as promising cancer biomarkers have been well recognized. Our study intends to explore the functions of lncRNA X-inactive specific transcript (DLX6-AS1) in NB and provide a potential action mechanism. METHODS: The expression of DLX6-AS1, miR-506-3p and signal transducer and activator of transcription 2 (STAT2) was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and colony formation assay. Cell cycle distribution was determined by flow cytometry assay. The protein level of cell cycle-related markers and STAT2 was detected by Western blot. Glycolysis progress was evaluated according to glucose consumption, lactate production and ATP level. The target genes were predicted by the online database Starbase3.0 and verified by dual-luciferase reporter assay. RESULTS: DLX6-AS1 expression was highly elevated in NB tissues and cells. DLX6-AS1 deficiency inhibited NB cell proliferation, cell cycle and glycolysis in vitro. MiR-506-3p was a target of DLX6-AS1, and miR-506-3p absence partly reversed the effects of DLX6-AS1 deficiency. Besides, STAT2 was targeted by miR-506-3p, and its expression was regulated by DLX6-AS1 through miR-506-3p. MiR-506-3p restoration also inhibited NB cell malignant behaviors, and STAT2 overexpression partially abolished the role of miR-506-3p restoration. Moreover, DLX6-AS1 deficiency weakened tumor growth in vivo. CONCLUSION: DLX6-AS1 regulated cell proliferation, cell cycle and glycolysis in vitro and tumor growth in vivo to promote the development of NB by upregulating STAT2 via targeting miR-506-3p.

Long Noncoding RNA Hypoxia-Inducible Factor-1 Alpha-Antisense RNA 1 Regulates Vascular Smooth Muscle Cells to Promote the Development of Thoracic Aortic Aneurysm by Modulating Apoptotic Protease-Activating Factor 1 and Targeting let-7g.

BACKGROUND: Thoracic aortic aneurysm (TAA) is a severe threat that is characterized by the increased aortic diameter. The dysfunction of vascular smooth muscle cells (VSMCs) contributes to the formation of TAA. Previous research indicated that long noncoding RNAs (lncRNAs) were involved in the development of TAA. This article aimed to explore the role of lncRNA hypoxia-inducible factor-1 alpha-antisense RNA 1 (HIF1A-AS1) and potential action mechanisms in VSMCs. METHODS: The expression of HIF1A-AS1, collagen I, collagen III, microRNA let-7g (let-7g) and apoptotic protease-activating factor 1 (APAF1) was detected by quantitative real-time polymerase chain reaction. Cell proliferation and cell apoptosis were assessed by Cell Counting Kit-8 and flow cytometry assays, respectively. The protein levels of proliferating cell nuclear antigen, Cleaved caspase-3 (Cleaved-cas3), B cell lymphoma/leukemia-2 (Bcl-2), Collagen I, Collagen III, and APAF1 were quantified by Western blot. The relationship between let-7g and HIF1A-AS1 or APAF1 was predicted by the online bioinformatics tool and verified by dual-luciferase reporter assay and RNA pull-down assay. RESULTS: HIF1A-AS1 was upregulated in TAA tissues and was a valuable diagnostic marker of TAA. HIF1A-AS1 overexpression suppressed proliferation, induced apoptosis, and reduced the expression of extracellular matrix proteins in VSMCs. let-7 g was a target of HIF1A-AS1, and its inhibition functioned the same role as HIF1A-AS1 overexpression. APAF1 was a target of let-7g, and its knockdown played the opposite role with HIF1A-AS1 overexpression. The reintroduction of let-7g or APAF1 knockdown reversed the effects of HIF1A-AS1 overexpression in VSMCs. CONCLUSIONS: HIF1A-AS1 regulated the proliferation, apoptosis ,and the activity of extracellular matrix proteins in VSMCs through modulating APAF1 by targeting let-7g, leading to the development of TAA.

[Expression of regulatory T cells and Foxp3 gene in peripheral blood of children with aplastic anemia].

OBJECTIVE: To investigate the levels of CD4+CD25+CD127(low) regulatory T cells (Tregs) and the expression of Foxp3 gene in peripheral blood of children with aplastic anemia (AA) and to study their roles in the pathogenesis of AA. METHODS: Twenty-one children with chronic AA, 9 with acute AA and 15 healthy children were enrolled. The proportion of CD4+CD25+ CD127low Tregs in CD4+ T cells was evaluated by flow cytometric analysis. The level of Foxp3 mRNA was ascertained by RT-PCR. RESULTS: The percentage of peripheral blood CD4+T cells and CD4+CD25+ and CD4+CD25+CD127(low) Tregs in CD4+T cells in both the acute and chronic AA groups was significantly lower than that in the normal control group (P<0.05).The acute AA group had more decreased CD4+ T cells and CD4+CD25+ and CD4+CD25+CD127(low) Tregs percentage compared with the CAA group (P<0.05). The expression of Foxp3 mRNA in peripheral blood decreased obviously in the acute AA group (0.47 + or - 0.08%) compared with that in the normal control (0.71 + or - 0.12%) and the CAA groups (0.68 + or - 0.14%) (P<0.05). CONCLUSIONS: The low expression of Tregs and Foxp3 mRNA in peripheral blood may be involved in pathogenesis of AA.The more decreased Tregs and Foxp3 mRNA expression in acute AA than chronic AA suggests their possible roles in the assessment of the severity of AA.