摘要: Objectives This study aims to reveal the roles and related mechanisms of LncRNA B4GALT1-AS1 in osteosarcoma (OS) cells stemness and migration. Materials and methods Real-time quantitative PCR (RT-qPCR) was used to detect the expression of several LncRNAs in OS tissues and normal adjacent tissues and in OS mammospheres and cells. Cell viability, transwell migration, tumour spheres formation and in vivo tumour formation assays were used to examine the effects of LncRNA B4GALT1-AS1 on OS progression. In addition, RNA immunoprecipitation (RIP) and Luciferase reporter assays were performed to determine the binding site of RNA-binding protein HuR on B4GALT1-AS1 and transcriptional factor YAP. Immunofluorescence analysis was used to examine YAP nuclear-cytoplasm translocation. Results LncRNA B4GALT1-AS1 expression was significantly increased in OS tissues and cells spheres. Knockdown of B4GALT1-AS1 inhibited OS cells proliferation, migration, stemness and chemotherapeutic sensitivity. Mechanistically, B4GALT1-AS1 recruited HuR to enhance YAP mRNA stability and thus its transcriptional activity. Conclusions We indicate that lncRNA B4GALT1-AS1 promotes OS cells stemness and migration via recruiting HuR to enhance YAP activity.

摘要: Objectives Prolyl hydroxylases (PHDs) play essential roles in oxygen-sensing system, whereas the effects of PHDs on inflammation have not been totally uncovered. Our study aimed to investigate the role of PHDs in lipopolysaccharide (LPS)-induced inflammation of human gingival fibroblasts (HGFs) and clarify the potential mechanisms. Materials and methods A pan hydroxylase inhibitor, dimethyloxallyl glycine (DMOG), and RNA interference were used to explore the role of PHDs in inflammation. Cytotoxic effect of DMOG was determined by cell-counting kit-8 and flow cytometry respectively. The secretion levels of IL-6 and IL-8 were assessed by ELISA. The mRNA levels of inflammatory cytokines, Toll-like receptor (TLR) 4 and MyD88 were evaluated by quantitative real-time PCR. The activation of NF-kappa B, mitogen-activated protein kinase (MAPK) and PI3K/AKT pathways were detected by western blot and the nuclear translocation of NF-kappa B p65 was examined by immunofluorescence. Downregulation of PHD1 and PHD2 was performed with siRNA transfection. Results Dimethyloxallyl glycine inhibited LPS-induced inflammatory cytokine, TLR4 and MyD88 expression in gene level and the elevated secretion of IL-6 and IL-8 was also downregulated. Additionally, LPS-induced activation of NF-kappa B, MAPK and AKT pathways was abolished by DMOG treatment. Importantly, LPS-induced inflammatory cytokine expression was merely suppressed by PHD2 knockdown. Conclusions Prolyl hydroxylases acted as a positive regulator in LPS-induced inflammation of HGFs via TLR4/MyD88-mediated NF-kappa B, MAPK and AKT signalling pathways and PHD2 among three isoforms was principally responsible for the effects.

摘要: ObjectivesMethamphetamine (MA) abuse evokes pulmonary toxicity. The aim of our study is to investigate if autophagy is induced by MA and if autophagy-initiated apoptosis in alveolar epithelial cells is involved in MA-induced chronic pulmonary toxicity. Materials and MethodsThe rats in Control group and MA group were tested by Doppler and HE staining. The alveolar epithelial cells were treated with MA, following by western blot, RT-PCR and immunofluorescence assay. ResultsChronic exposure to MA resulted in lower growth ratio of weight and in higher heart rate and peak blood flow velocity of the main pulmonary artery of rats. MA induced infiltration of inflammatory cells in lungs, more compact lung parenchyma, thickened alveolar septum and reduction in the number of alveolar sacs. In alveolar epithelial cells, the autophagy marker LC3 and per cent of cells containing LC3-positive autophagosome were significantly increased. MA dose dependently suppressed the phosphorylation of mTOR to inactivate mTOR, elicited autophagy regulatory proteins LC3 and Beclin-1, accelerated the transformation from LC3 I to LC3 II and initiated apoptosis by decreasing Bcl-2 and increasing Bax, Bax/Bcl-2 and cleaved Caspase 3. The above results suggest that sustained autophagy was induced by long-term exposure to MA and that the increased Beclin-1 autophagy initiated apoptosis in alveolar epithelial cells. ConclusionsConcurrence of autophagy with apoptosis in alveolar epithelial cells contributes to chronic pulmonary toxicity induced by MA.

摘要: Objective Accumulating data show that dysregulation of long noncoding RNAs (lncRNAs) acts a critical role in a variety of malignancies. Among these lncRNAs, small nucleolar RNA host genes (SNHGs) are associated with tumour growth and progression. But, the molecular mechanisms by which SNHG4 contributes to osteosarcoma remain undocumented. Methods The association between lncRNA SNHG4 expression and clinicopathologic characteristics and prognosis in patients with osteosarcoma was analysed by TCGA RNA-sequencing data. Cell viability and colony formation abilities were respectively assessed by MTT and colony formation assays. LncRNA SNHG4-specific binding with miR-224-3p was verified by bioinformatic analysis, luciferase gene report, and RNA immunoprecipitation assays. Regulation relationship between SNHG4 and miR-224-3p expression was further evaluated by the rescue experiments. Results The expression level of lncRNA SNHG4 was significantly elevated in osteosarcoma samples and cell lines as compared with the adjacent normal tissues, and SNHG4 high expression was associated with tumour size (TS) and poor prognosis in patients with osteosarcoma. Knockdown of SNHG4 suppressed cell viability and invasive potential, whereas ectopic SNHG4 expression displayed the opposite effects. Moreover, we found that lncRNA SNHG4 acted as a sponge of miR-224-3p, and miR-224-3p mimic reversed SNHG4 induced tumour-promoting effects in osteosarcoma cells. The expression of miR-224-3p depicted a negative correlation with SNHG4 in osteosarcoma samples and miR-224-3p low expression was associated with TS and poor survival in patients with osteosarcoma. Conclusion Our findings demonstrated that LncRNA SNHG4 promoted tumour growth by sponging miR-224-3p and represented a poor prognostic factor in patients with osteosarcoma.

摘要: Objective-catenin is one of the most critical oncogenes associated with many kinds of human cancers, especially in the human CRC. Innate immunity recognizes tumour derived damage-associated molecular patterns (DAMPs) and primes the anti-tumour adaptive responses. While the function of -catenin in CRC tumourigenesis is well established, its impact on innate immune evasion is largely unknown. The aim of this study is to characterize the role of -catenin in inhibiting RIG-I-like receptor (RLR)-mediated IFN- signalling in colorectal cancer. Materials and MethodsImmunohistochemical staining and western blotting were conducted to study the expression of -catenin, IRF3 and phospho-IRF3 (p-IRF3) in CRC samples and cell lines. Plaque assay determining virus replication was performed to assess the regulation of -catenin on IFN- signalling. The inhibition of -catenin on RLR-mediated IFN- signalling was further studied by real-time analyses and reporter assays in the context of lentiviral-mediated -catenin stably knocking down. Lastly, co-immunoprecipitation and nuclear fractionation assay were conducted to monitor the interaction between -catenin and IRF3. ResultsWe found that high expression of -catenin positively correlated with the expression of IRF3 in CRC cells. Overexpression of -catenin increased the viral replication. Conversely knocking down of -catenin inhibited viral replication. Furthermore, our data demonstrated that -catenin could inhibit the expression of IFN- and interferon-stimulated gene 56 (ISG56). Mechanistically, we found that -catenin interacted with IRF3 and blocked its nuclear translocation. ConclusionOur study reveals an unprecedented role of -catenin in enabling innate immune evasion in CRC.