摘要: Objectives Previously, our investigations demonstrated robust pro-angiogenic potentials of extracellular vesicles secreted by periodontitis-compromised dental pulp stem cells (P-EVs) when compared to those from healthy DPSCs (H-EVs), but the underlying mechanism remains unknown. Materials and methods Here, circulating microRNAs (miRNAs) specifically found in P-EVs (compared with H-EVs) were identified by Agilent miRNA microarray analysis, and the roles of the candidate miRNA in P-EV-enhanced cell angiogenesis were confirmed by cell transfection and RNA interference methods. Next, the direct binding affinity between the candidate miRNA and its target gene was evaluated by luciferase reporter assay. CCK-8, transwell/scratch wound healing and tube formation assays were established to investigate the proliferation, migration, and tube formation abilities of endothelial cells (ECs). Western blot was employed to measure the protein levels of Hedgehog/Gli1 signalling pathway components and angiogenesis-related factors. Results The angiogenesis-related miRNA miR-378a was found to be enriched in P-EVs, and its role in P-EV-enhanced cell angiogenesis was confirmed, wherein Sufu was identified as a downstream target gene of miR-378a. Functionally, silencing of Sufu stimulated EC proliferation, migration and tube formation by activating Hedgehog/Gli1 signalling. Further, we found that incubation with P-EVs enabled the transmission of P-EV-contained miR-378a to ECs. Subsequently, the expressions of Sufu, Gli1 and vascular endothelial growth factor in ECs were significantly influenced by P-EV-mediated miR-378a transmission. Conclusions These data suggest that P-EVs carrying miR-378a promote EC angiogenesis by downregulating Sufu to activate the Hedgehog/Gli1 signalling pathway. Our findings reveal a crucial role for EV-derived miR-378a in cell angiogenesis and hence offer a new target for modifying stem cells and their secreted EVs to enhance vessel regenerative potential.

摘要: Objectives Circular RNAs (circRNAs) are essential participants in tumour progression. This study focused on investigating the mechanism of a novel functional circRNA in gastric cancer (GC). Methods Gene expression was detected by qRT-PCR or Western blot. Survival curves were generated via Kaplan-Meier method. In vitro and in vivo assays were used to investigate the impact of circ_SMAD4 on GC cell growth and tumorigenesis. Agarose gel electrophoresis assay, RNase R treatment and Sanger sequencing were utilized for confirming the circular structure of circ_SMAD4. Relationship between molecules was monitored by a series of mechanical experiments, as needed. Results Circ_SMAD4 expression was potentiated in GC. Circ_SMAD4 depletion impeded GC cell growth in vitro and restrained tumorigenesis in vivo. Mechanically, nuclear circ_SMAD4 recruited TCF4 to facilitate CTNNB1 transcription, while cytoplasmic circ_SMAD4 sequestered miR-1276 to prevent the silence of CTNNB1 mRNA, leading to activation of Wnt/beta-catenin pathway. Rescue experiments validated that circ_SMAD4 depended on miR-1276/TCF4-regulated CTNNB1 to elicit accelerating effects on GC cell growth. Conclusion Circ_SMAD4 facilitated GC tumorigenesis by activating CTNNB1-dependent Wnt/beta-catenin pathway. Hopefully, the findings could provide new clues for improving GC prognosis and treatment.

摘要: Osteosarcoma is the most common primary bone malignancy and is a neoplasm thought to be derived from the bone-forming mesenchymal stem cells. Aberrant activation of oncogenes and inactivation of tumour suppressor genes by somatic mutations and epigenetic mechanisms play a pivotal pathogenic role in osteosarcoma. Aside from alterations in these protein-coding genes, it has now been realized that dysregulation of non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and the recently discovered circular RNAs (circRNAs), is crucial to the initiation and progression of osteosarcoma. CircRNAs are single-stranded RNAs that form covalently closed loops and function as an important regulatory element of the genome through multiple machineries. Recently, an increasing number of studies suggested that circRNAs also played critical roles in osteosarcoma. This review summarizes recent development and progression in circRNA transcriptome analysis and their functions in the modulation of osteosarcoma progression.

摘要: Objectives Induction of deactivation and apoptosis of hepatic stellate cells (HSCs) are principal therapeutic strategies for liver fibrosis. Kruppel-like factor 14 (KLF14) regulates various biological processes, however, roles, mechanisms and implications of KLF14 in liver fibrosis are unknown. Materials and Methods KLF14 expression was detected in human, rat and mouse fibrotic models, and its effects on HSCs were assessed. Chromatin immunoprecipitation assays were utilized to investigate the binding of KLF14 to peroxisome proliferator-activated receptor gamma (PPAR gamma) promoter, and the binding of enhancer of zeste homolog 2 (EZH2) to KLF14 promoter. In vivo, KLF14-overexpressing adenovirus was injected via tail vein to thioacetamide (TAA)-treated rats to investigate the role of KLF14 in liver fibrosis progression. EZH2 inhibitor EPZ-6438 was utilized to treat TAA-induced rat liver fibrosis. Results KLF14 expression was remarkably decreased in human, rat and mouse fibrotic liver tissues. Overexpression of KLF14 increased LD accumulation, inhibited HSCs activation, proliferation, migration and induced G2/M arrest and apoptosis. Mechanistically, KLF14 transactivated PPAR gamma promoter activity. Inhibition of PPAR gamma blocked the suppressive role of KLF14 overexpression in HSCs. Downregulation of KLF14 in activated HSCs was mediated by EZH2-regulated histone H3 lysine 27 trimethylation. Adenovirus-mediated KLF14 overexpression ameliorated TAA-induced rat liver fibrosis in PPAR gamma-dependent manner. Furthermore, EPZ-6438 dramatically alleviated TAA-induced rat liver fibrosis. Importantly, KLF14 expression was decreased in human with liver fibrosis, which was significantly correlated with EZH2 upregulation and PPAR gamma downregulation. Conclusions KLF14 exerts a critical anti-fibrotic role in liver fibrosis, and targeting the EZH2/KLF14/PPAR gamma axis might be a novel therapeutic strategy for liver fibrosis.

摘要: Objectives The present study clarified the role and signalling pathway of Ski in regulating proliferation and apoptosis in fibroblasts under high-glucose (HG) conditions. Materials and Methods The proliferation and apoptosis of rat primary fibroblasts were assessed using EdU incorporation and TUNEL assays. The protein and phosphorylation levels of the corresponding factors were measured using immunofluorescence staining and Western blotting. Immunoprecipitation was used to determine the interactions between Ski and FoxO1 or Ski and HDAC1. The Ski protein was overexpressed via recombinant adenovirus transfection, and FoxO1 and HDAC1 were knocked down using targeted small-interfering RNA. Results The present study found that HG inhibited fibroblast proliferation, increased apoptosis and reduced Ski levels in rat primary fibroblasts. Conversely, increasing Ski protein levels alleviated HG-induced proliferation inhibition and apoptosis promotion. Increasing Ski protein levels also increased Ski binding to FoxO1 to decrease FoxO1 acetylation, and interfering with FoxO1 caused loss of the regulatory effect of Ski in fibroblasts under HG. Increasing Ski protein levels decreased FoxO1 acetylation via HDAC1-mediated deacetylation. Conclusions Therefore, these findings confirmed for the first time that Ski regulated fibroblast proliferation and apoptosis under HG conditions via the FoxO1 pathway.