Tumor-associated macrophages (TAMs) in the tumor microenvironment have been associated with enhanced tumor progression. In this study, we investigated the role and molecular mechanisms of MALAT1 in TAMs derived from thyroid cancer. The expression of MALAT1 and FGF2 in thyroid cancer tissues and cells were measured by quantitative real-time PCR and Western blot. TAMs were transfected with indicated constructs. Then the culture medium (CM) from TAMs was harvested for assay. Secreted FGF2 protein levels and TNF-α, IL-12, and IL-10 levels were detected by ELISA. The cell proliferation, migration, and invasion of FTC133 cells were determined with a CCK-8 assay and a Transwell assay, respectively. In addition, HUVEC vasculature formation was measured by matrigel angiogenesis assay. The higher levels of MALAT-1 and FGF2 were observed in thyroid cancer tissues and in thyroid cancer cells compared to that in the control. Besides, in the presence of si-MALAT1, the levels of TNF-α and IL-12 were significantly up-regulated whereas IL-10 was down-regulated in the CM from TAMs. Moreover, down-regulation of MALAT1 in TAMs reduced proliferation, migration, and invasion of FTC133 cells and inhibited angiogenesis. However, overexpression of FGF2 blocked the effects of MALAT1 siRNAs on cell migration, invasion, and angiogenesis. Our results suggest that MALAT1-mediated FGF2 protein secretion from TAMs inhibits inflammatory cytokines release, promotes proliferation, migration, and invasion of FTC133 cells and induces vasculature formation. J. Cell. Biochem. 118: 4821-4830, 2017. © 2017 Wiley Periodicals, Inc.

Alginate, a natural acidic polysaccharide extracted from marine brown seaweeds, is composed of different blocks of β-(1, 4)-D-mannuronate (M) and its C-5 epimer α-(1, 4)-L-guluronate (G). Alginate-derived guluronate oligosaccharide (GOS) readily activates macrophages. However, to understand its role in immune responses, further studies are needed to characterize GOS transport and signalling. Our results show that GOS is recognized by and upregulates Toll-like receptor 4 (TLR4) on RAW264.7 macrophages, followed by its endocytosis via TLR4. Increased expression of TLR4 and myeloid differentiation protein 2 (MD2) results in Akt phosphorylation and subsequent activation of both nuclear factor-κB (NF-κB) and mechanistic target of rapamycin (mTOR). Moreover, GOS stimulates mitogen-activated protein kinases (MAPKs); notably, c-Jun N-terminal kinase (JNK) phosphorylation depends on TLR4 initiation. All these events contribute to the production of inflammatory mediators, either together or separately. Our findings also reveal that GOS induces cytoskeleton remodelling in RAW264.7 cells and promotes macrophage proliferation in mice ascites, both of which improve innate immunity. Conclusively, our investigation demonstrates that GOS, which is dependent on TLR4, is taken up by macrophages and stimulates TLR4/Akt/NF-κB, TLR4/Akt/mTOR and MAPK signalling pathways and exerts impressive immuno-stimulatory activity.

Alginate has notably diverse pharmacological activities. The present study investigated the anti-inflammatory activity of the guluronate oligosaccharides prepared by oxidative degradation (GOS-OD) from alginate. GOS-OD significantly attenuated the production of nitric oxide (NO), prostaglandin E2 (PGE2), and reactive oxygen species (ROS), the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, and the secretion of pro-inflammatory cytokines in lipopolysaccharide (LPS)-activated murine macrophage RAW 264.7 cells. Moreover, GOS-OD potently decreased the binding of LPS to the cell surface and LPS-induced Toll-like receptor 4 (TLR4) and cluster of differentiation (CD) 14 expression. Additionally, GOS-OD could remarkably inhibit the LPS-induced activation of nuclear factor (NF)-κB and mitogen-activated protein (MAP) kinase pathways in RAW 264.7 cells. These results indicate that GOS-OD may reduce the LPS-stimulated inflammatory responses through blocking the activation of NF-κB and MAP kinases, suggesting that GOS-OD may be considered as a potential nutraceutical for inflammation.

Integrin α6 (ITGA6), a transmembrane glycoprotein adhesion receptor protein, is widely upregulated in many types of tumors and promotes migration and invasion in cancer cells. However, the role that the ITGA6-associated signaling network plays in radiosensitivity in breast cancer has not been described. The expression of ITGA6 was examined in human breast cancer and normal breast cell lines using western blot analysis. We also explored the role of ITGA6 in the regulation of radiation sensitivity in breast cancer using the colony formation assays, cell cycle analyses, apoptosis assays and immunofluorescence analyses. The results showed that the protein and mRNA expression levels of ITGA6 was higher in breast cancer cells than in normal cells. ITGA6 protectived responses to radiotherapy in breast cancer cells by altering cell apoptosis, DNA damage repair and cell-cycle regulation. Furthermore, ITGA6 enhanced radiation resistance via PI3K/Akt and MEK/Erk signaling. In addition, overexpressing ITGA6 promoted radiation resistance in cells, and this effect was neutralized by the PI3K inhibitor LY294002 and MEK inhibitor U0126. Taken together, these findings indicate that ITGA6 might be involved in a mechanism that underlies radiation resistance and that ITGA6 could be a potential target for therapies aimed at overcoming radiation resistance in breast cancer.

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BackgroundEpstein-Barr virus (EBV) is ubiquitously associated with nasopharyngeal carcinoma (NPC). EBV encodes two groups of microRNAs (miRNAs) which are divided into BamHI fragment H rightward open reading frame 1 (BHRF1) and BamHI-A rightward transcripts (BART) microRNAs. EBV miR-BART has been found to be involved in the development and progression of NPC. However, so far the role of EBV-miR-BART8-3p in NPC progression remains unknown. This study aimed to investigate the role of EBV-miR-BART8-3p in NPC and explore the underlying mechanisms.MethodsmiRNA expression was profiled in NPC and normal nasopharyngeal mucosal specimens using miRNA sequencing. EBV-miR-BART8-3p and RNF38 expression was quantified with qPCR assay. The migration, invasion and metastasis of NPC cells were evaluated using CCK-8, colony-forming, wound-healing, and migration and invasion assays. The expression levels of epithelial-mesenchymal transition (EMT)-related markers,metastasis-related markers and NF-κB and Erk1/2 signaling proteins were determined using Western blotting. Tumorigenic assay was performed to evaluate the pulmonary metastatic ability of NPC cells in vivo.ResultsEBV BART miRNAs were highly over-expressed and co-expressed in NPC and might be associated with deactivated immune response in NPC according to the sequencing analysis. EBV-miR-BART8-3p expression was significantly higher in human NPC specimens than in normal nasopharyngeal mucosal specimens. EBV-miR-BART8-3p was found to promote NPC migration, invasion and metastasis, drove an EMT process and upregulated expression of metastasis-related proteins expression in NPC cells. Our data showed EBV-miR-BART8-3p directly targeted RNF38 in NPC cells.ConclusionThe present study demonstrates that EBV-miR-BART8-3p plays a significant role in inducing EMT and promoting metastasis through directly targeting RNF38 in NPC cells via the activation of NF-κB and Erk1/2 signaling pathways. Our findings suggest that EBV-miR-BART8-3p is a potential therapeutic target for NPC.Electronic supplementary materialThe online version of this article (10.1186/s13046-018-0953-6) contains supplementary material, which is available to authorized users.

Dysregulation of microRNAs (miRNAs) has been associated with malignant behavior in a variety of cancers. Our previous study demonstrated that miRNA expression profiles are predictors for patients with advanced non-small cell lung cancer (NSCLC). We also showed that miRNAs are involved in small-cell lung cancer metastasis. Here, we used qRT-PCR to re-analyze our previous microarray results using serum samples from 75 patients with NSCLC. Surprisingly, we found that miR-574-5p and miR-874 were overexpressed in patients with metastatic advanced NSCLC but not in patients with non-metastatic advanced NSCLC. Additionally, miR-574-5p expression was correlated between matched serum and tissue samples from 68 patients. However, these 2 miRNAs are not prognostic factors for NSCLC. Transwell and wound-healing assays showed that miR-574-5p promotes the migration and invasion of NSCLC cells. Furthermore, miR-574-5p enhanced the tyrosine phosphorylation of β-catenin by repressing PTPRU expression in vitro. In conclusion, this study explored the expression of miR-574-5p in clinical samples and its molecular mechanisms in the metastasis of advanced NSCLC.

Haemophilus parasuis can be either a commensal bacterium of the porcine respiratory tract or an opportunistic pathogen causing Glässer's disease, a severe systemic disease that has led to significant economical losses in the pig industry worldwide. We determined the complete genomic sequence of H. parasuis SH0165, a highly virulent strain of serovar 5, which was isolated from a hog pen in North China. The single circular chromosome was 2,269,156 base pairs in length and contained 2,031 protein-coding genes. Together with the full spectrum of genes detected by the analysis of metabolic pathways, we confirmed that H. parasuis generates ATP via both fermentation and respiration, and possesses an intact TCA cycle for anabolism. In addition to possessing the complete pathway essential for the biosynthesis of heme, this pathogen was also found to be well-equipped with different iron acquisition systems, such as the TonB system and ABC-type transport complexes, to overcome iron limitation during infection and persistence. We identified a number of genes encoding potential virulence factors, such as type IV fimbriae and surface polysaccharides. Analysis of the genome confirmed that H. parasuis is naturally competent, as genes related to DNA uptake are present. A nine-mer DNA uptake signal sequence (ACAAGCGGT), identical to that found in Actinobacillus pleuropneumoniae and Mannheimia haemolytica, followed by similar downstream motifs, was identified in the SH0165 genome. Genomic and phylogenetic comparisons with other Pasteurellaceae species further indicated that H. parasuis was closely related to another swine pathogenic bacteria A. pleuropneumoniae. The comprehensive genetic analysis presented here provides a foundation for future research on the metabolism, natural competence and virulence of H. parasuis.