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At least 667 records · Page 37

Keratin 13 gene is epigenetically suppressed during transforming growth factor-β1-induced epithelial-mesenchymal transition in a human keratinocyte cell line

Highlights: • TGF-β1 induced mesenchymal-like morphology in HaCaT cells. • TGF-β1-induced EMT partially controlled the gene expression of EMT markers. • KRT13 was identified as a TGF-β1-responsive epithelial marker in HaCaT cells. • Chromatin state of the KRT13 promoter was epigenetically regulated during EMT. Epithelial-mesenchymal transition (EMT) is a biological event in which epithelial cells lose their polarity and cell–cell adhesions and concomitantly acquire mesenchymal traits, and is thought to play an important role in pathological processes such as wound healing and cancer progression. In this study, we evaluated transforming growth factor (TGF)-β1-treated human keratinocyte HaCaT cells as an in vitro model of EMT. HaCaT cells were changed into an elongated fibroblast-like morphology, which is indicative of EMT in response to TGF-β1. Phalloidin staining demonstrated the formation of actin stress fibers in TGF-β1-treated cells. Quantitative RT-PCR analysis revealed that TGF-β1 increased the mRNA levels of EMT transcription factors (SNAI2, TWIST1, and ZEB1) and mesenchymal markers (CDH2, VIM, and FN1), while it decreased the transcripts of epithelial phenotypic genes (CLDN1, OCLN, KRT5, KRT15, KRT13, and TGM1). Furthermore, we found that KRT13 was drastically suppressed through the reduction of RNA polymerase II occupancy of its promoter, which was accompanied by a decrease in active histone marks (H3K4me3 and H3K27ac) and an increase in a repressive mark (H3K27me3) during EMT. These findings indicate that the TGF-β1-induced EMT program regulates a subset of epithelial and mesenchymal marker genes, and that KRT13 is transcriptionally suppressed through the modulation of the chromatin state at the KRT13 promoter in HaCaT cells.

60 APPLIED LIFE SCIENCES↗

A novel circular RNA, hsa{sub c}irc{sub 0}046701, promotes carcinogenesis by increasing the expression of miR-142-3p target ITGB8 in glioma

Highlights: • We identified a novel circular RNA, hsa{sub c}irc{sub 0}046701 in glioma cells. • Hsa{sub c}irc{sub 0}046701 was significantly upregulated in glioma tissues. • Hsa{sub c}irc{sub 0}046701 sponges miR-142-3p in glioma. • MiR-142-3p directly targets ITGB8 in glioma. • Hsa{sub c}irc{sub 0}046701/miR-142-3p/ITGB8 axis plays critical roles in glioma pathogenesis. In the present study, we identified a novel circular RNA (circRNA), hsa{sub c}irc{sub 0}046701, in glioma cells. We measured the expression of hsa{sub c}irc{sub 0}046701 using qRT-PCR in glioma tissues and cell lines, and explored its functions using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, colony formation, and Transwell assays. Luciferase reporter assays were performed to validate the correlation between microRNA miR-142-3p and hsa{sub c}irc{sub 0}046701 or integrin subunit beta 8 (ITGB8). The results showed that hsa{sub c}irc{sub 0}046701 was significantly upregulated in glioma tissues and cell lines, and knockdown of hsa{sub c}irc{sub 0}046701 inhibited cell proliferation and invasion. Luciferase reporter assays indicated that hsa{sub c}irc{sub 0}046701 functions as a sponge for miR-142-3p and regulates the expression of ITGB8. Subsequently, functional assays revealed that silencing of hsa{sub c}irc{sub 0}046701 could upregulate miR-142-3p, resulting in downregulation of ITGB8. The results demonstrated that the hsa{sub c}irc{sub 0}046701/miR-142-3p/ITGB8 axis might play critical regulatory roles in the pathogenesis and development of glioma.

60 APPLIED LIFE SCIENCES↗

LncRNA CCND2-AS1 promotes proliferation, migration, and invasion in papillary thyroid carcinoma

In decades, a lot of long non-coding RNAs (LncRNAs) have been proven to exert influences on tumorigenesis in vitro and in vivo. Many lncRNAs have been reported as effective therapeutic targets and biomarkers in various cancers. However, whether LncRNAs are associated with the progression of PTC remains largely unknown. In this study, we measured the expression of CCND2-AS1 in PTC cell lines by quantitative real-time polymerase chain reaction (qRT-PCR).We found that CCND2-AS1 expression was significantly over-expressed in PTC cell lines compared to normal thyroid epithelial cells. Gain-and loss-of-function experiments were performed to investigate the role of CCND2-AS1 in PTC cells. In vitro experiments, we proved that CCND2-AS1 knockdown in TPC1 significantly suppressed cell proliferation, migration, and invasion, while CCND2-AS1 overexpression in BCPAP had the opposite effects. Meanwhile, we also found that CCND2-AS1 could regulate N-cadherin and Vimentin expression, which may influence invasion and migration. Our findings indicate that the lncRNA CCND2-AS1 is a gene associated with PTC and might become a potential therapeutic target.

60 APPLIED LIFE SCIENCES↗

Trek2a regulates gnrh3 expression under control of melatonin receptor Mt1 and α2-adrenoceptor

Gonadotrophin-releasing hormone (GnRH) expression is associated with the two-pore domain potassium ion (K{sup +}) channel-related K{sup +} (TREK) channel trek2a expression and melatonin levels. We aimed to investigate correlation of trek2a expression with gnrh3 expression, and regulatory mechanisms of trek2a expression by the melatonin receptor Mt1 and α{sub 2}-adrenoceptor which are regulated by melatonin. trek2a specific siRNA, Mt1 antagonist luzindole and α{sub 2}-adrenoceptor antagonist prazosin were administered into the adult zebrafish brain and gene expressions were examined by real-time PCR. trek2a specific siRNA administration significantly reduced expression levels of trek2a, gnrh3 and mt1. Luzindole administration suppressed trek2a and gnrh3 expressions. Prazosin administration reduced trek2a and gnrh3 expressions. It is suggested that Trek2a regulates gnrh3 expression under the control of Mt1 and α{sub 2}-adrenoceptor.

60 APPLIED LIFE SCIENCES↗

Differences in TLR7/8 activation between monocytes and macrophages

Highlights: • Only TLR8 agonists induced NF-κB and ISG activation in monocytes. • TLR8 could inhibit TLR7-induced NF-κB activation in monocytes. • Both TLR7 and TLR8 agonists only induced NF-κB but not ISG activation in macrophages. • Differences in expression levels of molecules involved in TLR signaling between monocytes and macrophages. • Comparison between monocytes and macrophages in expression levels of molecules after TLR7/8 activation. The recognition of single-stranded RNA by TLR7/8 leads to the production of NF-κB-mediated cytokines and type I IFNs. However, the role of TLR7/8 activation in monocytes and macrophages is still unclear. The aim of this study was to investigate the differences in the activation of TLR7/8 between these two cell types. Microarray analysis, qRT-PCR and flow cytometry were used to analyse TLR7/8 signalling pathways in monocytes and macrophages after stimulation with agonists. Our data indicated that TLR8 agonists activated the NF-κB- and IRF-mediated pathways in THP-1 cells, whereas TLR7 agonists did not. However, silent TLR8 and enhanced TLR7 expression could increase TLR7-induced NF-κB activation in monocytes. TLR7 and TLR8 agonists induced NF-κB activation but no ISG response in PMA-differentiated THP-1 cells. The mRNA levels of pro-inflammatory cytokine were elevated upon CL075 stimulation in macrophages compared to monocytes. Thus, TLR7 and TLR8 might modulate different immune responses in monocytes and macrophages.

60 APPLIED LIFE SCIENCES↗

Glucagon-like peptide-1 contributes to increases ABCA1 expression by downregulating miR-758 to regulate cholesterol homeostasis

Abnormal regulation of lipid metabolism is associated with type 2 diabetes mellitus (T2DM). GLP-1 as a new treatment for T2DM, has unique effects in modulating cholesterol homeostasis. However, the mechanism of this effect is largely missing. The aim of this study was to determine the effects of GLP-1 on cholesterol-induced lipotoxicity in hepatocytes and examine the underlying mechanisms. The cell viability was determined, and caspase-3 was used to detect the effects of GLP-1 on cholesterol-induced apoptosis. The alterations of miR-758 and ATP-binding cassette transporter A1 (ABCA1) resulting from cholesterol incubation or GLP-1 were detected by qRT-PCR and Western blot assays. Overexpression of miR-758 abrogated the GLP-1-mediated ABCA1 expression, and conversely, down-regulation of miR-758 aggravated GLP-1's action and revealed significant promotion effects. BODIPY-Cholesterol efflux assay revealed that treatment with miR-758 inhibitor significantly enhanced ABCA1-dependent cholesterol efflux, resulting in reduced total cholesterol. Furthermore, Oil red O staining and cholesterol measurement were used to detect lipid accumulation. As a result, cholesterol significantly attenuated cell viability, promoted cell apoptosis, and facilitated lipid accumulation, and these effects were reversed by GLP-1. This study provides evidence that, in HepG2 cells, GLP-1 may affect cholesterol homeostasis by regulating the expression of miR-758 and ABCA1. These data can inform the development of biomarkers for miR-758, and potentially other drugs, on the key pathways of lipid metabolism.

60 APPLIED LIFE SCIENCES↗

Combined inhibition of EGFR and c-ABL suppresses the growth of fulvestrant-resistant breast cancer cells through miR-375-autophagy axis

Highlights: • Combined treatment with lapatinib and imatinib suppresses the growth of FRBC cells. • MiR-375 is the target of dual treatment. • MiR-375 may act as a downstream target by downregulating autophagy. Fulvestrant is the FDA-approved “pure anti-estrogen” agent for malignant breast cancer therapy. But endocrine resistance causes drug failure. A new approach is desired for fulvestrant-resistant breast cancer (FRBC) therapy. This study aims to find an effective approach to inhibit FRBC for patients with advanced breast cancer. MTT assay was first performed to detect the effect of inhibitors of c-ABL (imatinib) and EGFR (lapatinib) on FRBC cells. Microarray analysis was carried out to identify microRNA which is significantly changed between parental and FRBC cells. The related mechanisms were analyzed by qRT-PCR, MTT, AO staining and western blotting. Dual treatment significantly inhibited cell growth of FRBC and upregulated microRNA-375 (miR-375). Overexpression of miR-375 inhibited growth of FRBC cells, reduced autophagy, and decreased expression of ATG7 and LC3-II. Dual treatment elevated expression of miR-375 more than any single one of these two inhibitors. Overexpression of miR-375 increased cell growth inhibition induced by dual treatment, and the effect was attenuated when miR-375 was inhibited. In conclusion, we identified that combined inhibition of EGFR and c-ABL can suppress the growth of FRBC cells and elucidated a mechanism within FRBC cells involving regulation of miR-375 and autophagy. Dual treatment may be useful for inhibiting fulvestrant-resistant breast cancer.

60 APPLIED LIFE SCIENCES↗

Chronic cold exposure results in subcutaneous adipose tissue browning and altered global metabolism in Qinghai-Tibetan plateau pika (Ochotona curzoniae)

Highlights: • Adipose tissue adaptation to winter cold stress in Tibetan plateau pika was analyzed. • Decreased white adipose tissue (AT) and increased brown AT mass were observed. • Molecular and histological evidence of white AT browning was observed. • The shift from WAT to BAT enables increased thermogenesis in winter pika. The plateau pika (Ochotona curzoniae), one of the indigenous animals of the Qinghai-Tibet Plateau, is adapted to life in a cold and hypoxic environment. We conducted a series of genomic, proteomic and morphological studies to investigate whether changes in energy metabolism contribute to adaptation of the plateau pika to cold stress by analyzing summer and winter cohorts. The winter group showed strong morphological and histological features of brown adipose tissue (BAT) in subcutaneous white adipose tissue (sWAT). To obtain molecular evidence of browning of sWAT, we performed reverse transcription and quantitative real-time PCR, which revealed that BAT-specific genes, including uncoupling protein 1 (UCP-1) and PPAR-γ coactivator 1α (PGC-1α), were highly expressed in sWAT from the winter group. Compared with the summer group, Western blot analysis also confirmed that UCP-1, PGC-1α and Cox4 protein levels were significantly increased in sWAT from the winter group. Increased BAT mass in the inter-scapular region of the winter group was also observed. These results suggest that the plateau pika adapts to cold by browning sWAT and increasing BAT in order to increase thermogenesis. These changes are distinct from the previously reported adaptation of highland deer mice. Understanding the regulatory mechanisms underlying this adaptation may lead to novel therapeutic strategies for treating obesity and metabolic disorders.

60 APPLIED LIFE SCIENCES↗

Identification of aberrant circular RNA expression and its potential clinical value in primary great saphenous vein varicosities

Highlights: • This study identified 232 significantly aberrant circRNAs in primary great saphenous vein varicosities (PGSVVs). • A circRNA-miRNA-gene co-expression network was created. • Hsa{sub c}irc{sub 0}006427, hsa{sub c}irc{sub 0}089810 and hsa{sub c}irc{sub 0}005267 might be potential biological markers for PGSVVs. This study aimed to identify aberrant circRNA expression in primary great saphenous vein varicosities (PGSVVs) and investigate its potential clinical significance. High-throughput sequencing was applied to analyze the differential expression of circRNAs in three paired vein samples of PGSVVs and a control group. Computational bioinformatics analyses, including gene ontology (GO) analysis and encyclopedia of genes and genomes (KEGG) pathway analysis, were performed to further enrich microRNA data. Real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to verify the selected aberrant circRNAs in all vein samples, and a receiver operating characteristic (ROC) curve was plotted to evaluate the diagnostic and potential clinical significance. A total of 232 circRNAs were significantly aberrantly expressed in PGSVVs, including 105 and 127 upregulated and downregulated circRNAs, respectively. The predicted top 10 downstream miRNAs of the significantly altered circRNAs are hsa-miR-103a-2-5p, hsa-miR-141-5p, hsa-miR-3692-5p, hsa-miR-4659a-3p, hsa-miR-4659b-3p, hsa-miR-4691-5p, hsa-miR-4778-3p, hsa-miR-6738-3p, hsa-miR-6792-3p and hsa-miR-6873-3p. GO analysis revealed that the most enriched and meaningful biological process, cellular component, and molecular function terms were related to the regulation of catabolic processes, the cytoplasm and ATP binding, respectively. The most enriched and meaningful pathways revealed by KEGG pathway analysis were related to “axon guidance” “vitamin digestion and absorption” and “NF-Kappa B signaling pathway”. Hsa{sub c}irc{sub 0}006427 (P = 0.007), hsa{sub c}irc{sub 0}089810 (P = 0.044) and hsa{sub c}irc{sub 0}005267 (P = 0.049) were significantly downregulated in the PGSVV group relative to their expression levels in the control group, and the area under the ROC curve was 0.9091, 0.8025 and 0.8148, respectively. This study demonstrated that circRNAs were differentially expressed in PGSVVs, and highlights the crucial roles of circRNAs in the pathogenesis of PGSVVs and indicates that hsa{sub c}irc{sub 0}006427, hsa{sub c}irc{sub 0}089810 and hsa{sub c}irc{sub 0}005267 might be potential diagnostic and clinical biological markers.

60 APPLIED LIFE SCIENCES↗

Giantin is required for coordinated production of aggrecan, link protein and type XI collagen during chondrogenesis

Highlights: • Specificity of giantin for intracellular traffic of cartilage ECM is proposed. • Loss of giantin result in decreased of aggrecan, link protein and hyaluronan. • Loss of giantin cause increased type XI collagen. • Giantin is involved in perichondrium differentiation. Extracellular matrix (ECM) constitutes a proper micro-environment for cell proliferation, migration and differentiation, as well as playing pivotal roles in developmental processes including endochondral ossification. Cartilage ECM is mainly composed of fibrous proteins, including collagen, proteoglycan, and hyaluronan. Because almost all ECM components are transported by intracellular vesicular transport systems, molecules that mediate vesicle transport are also important for endochondral ossification. Giantin, encoded by the Golgb1 gene, is a tethering factor for coatomer 1 (COPI) vesicles and functions in the cis-medial Golgi compartments. An insertion mutation in the Golgb1 gene, resulting in a lack of giantin protein expression, has been detected in ocd/ocd rats that exhibit a pleiotropic phenotype including osteochondrodysplasia. To reveal the function of giantin in chondrogenesis, the present study assessed the effects of loss of giantin expression on cartilage ECM and Golgi morphology. Giantin was expressed in normal, but not in ocd/ocd, chondrocytes in the epiphyseal areas of embryonic femurs, whereas GM130 was expressed in both normal and ocd/ocd chondrocytes. The staining intensities of safranin O and azan (aniline blue) were reduced and enhanced, respectively, in epiphyseal cartilage of ocd/ocd femurs. Immunostaining showed that levels of type II collagen and fibronectin were comparable in normal and ocd/ocd cartilage. Levels of type XI collagen were higher, while levels of aggrecan, link protein and hyaluronan were lower, in ocd/ocd than in normal cartilage, although semi-quantitative RT-PCR showed similar levels of type XI collagen, aggrecan and link protein mRNAs in normal and ocd/ocd cartilage. Isolated chondrocytes of ocd/ocd and normal rats showed similar immunostaining patterns for cis-, medial-, and trans-Golgi marker proteins, whereas monolayers of ocd/ocd chondrocytes showed reduced levels of aggrecan and link protein and increased level of type XI collagen in spite of similar transcripts levels. These findings suggest that giantin plays a pivotal role in coordinated production of aggrecan, link protein and type XI collagen in chondrocytes, and that loss of giantin causes osteochondrodysplasia with disturbance of these ECM components.

60 APPLIED LIFE SCIENCES↗

PIL5 represses floral transition in Arabidopsis under long day conditions

Highlights: • PIL5 acts as an important factor affecting transitions in plants. • PIL5 represses floral transition through affecting the transcription of FT, SOC1, LFY. • PIL5 inhibits GA biosynthesis to repress flowering in Arabidopsis. PHYTOCHROME INTERACING FACTOR 3 LIKE 5 (PIL5), also named PHYTOCHROME INTERACTING FACTOR 1 (PIF1) is an important b-HLH transcription factor in Arabidopsis thaliana. Here we show that mutant of pil5-1 displays early flowering phenotype. We demonstrate that the expressions of the major flowering promoter genes [FLOWERING LOCUS T (FT), SUPPRESOR OF OVEREXPRESSION OF CO 1 (SOC1), and LEAFY (LFY)] are upregulated in the mutant of pil5-1. There is a significant increase of the mRNA of PIL5 in the mutants of co2-1, ft-10, soc1-2, and lfy-4. These changes provide the molecular evidence that PIL5 interacts with the flowering regulators to control flowering time. Moreover, it is shown in our results that PIL5 mutation mediates the increased contents of gibberellic acid (GA). Which is further supported by the qRT-PCR analysis, an increased transcriptome level of the GA biosynthesis genes (GA3ox1, GA3ox2, GA20ox1, GA20ox2, and GA20ox3) has been observed in the pil5-1 mutants as compared to the wild type. Collectively, PIL5 is involved in floral transition interacting with flowering integrators and GA.

60 APPLIED LIFE SCIENCES↗

Exosomal miR-675 from metastatic osteosarcoma promotes cell migration and invasion by targeting CALN1

Highlights: • Metastatic OS-derived exosomes induce the migration and invasion of osteoblast. • The expression of miR-675 is higher in metastatic OS-derived exosomes. • Exosomal miR-675 regulate the migration and invasion of osteoblast by down-regulating the expression of CALN1. • The expression of exosomal miR-675 is higher in metastatic OS patients' serum sample. Exosomal microRNAs(miRNAs) transfer from tumor to stromal cells is reportedly associated with cancer progression and metastasis in various epithelial cancers. However, the role of exosomal miRNA in the metastasis of osteosarcoma(OS) -the most common bone malignancy-still largely remains unknown. In this study, we purified exosomes with a median size close to 100 nm from cell culture media as well as patient serum, and proved that exosomes derived from the metastatic, but not the non-metastatic OS cells increase the migration and invasion of non-malignant fibroblast cells (hFOB1.19) in vitro. Furthermore, the differential miRNA cargo between metastatic and non-metastatic OS is identified by small RNA sequencing and RT-PCR validation, we found a highly expression of exosomal, but not cellular miR-675 level in the metastatic OS cell-lines compared with non-metastatic counterparts. Meanwhile, we also found that exosomal miR-675 could down-regulate CALN1 expression in recipient cell, which may influence the invasion and migration of hFOB1.19. Finally, the up regulation serum exosomal miR-675 and down regulation of CALN1 in tumor specimen was also found to be associated with the metastatic phenotype in OS patients. Our findings indicate that the exosomal miR-675 is a gene associated with OS and serum exosomal miR-675 expression may serve as a novel biomarker for the metastasis of OS.

60 APPLIED LIFE SCIENCES↗

Involvement of prostatic interstitial cells of Cajal in inflammatory cytokines-elicited catecholamines production: Implications for the pathophysiology of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS)

Highlights: • Prostatic ICCs express enzymes essential for catecholamine synthesis. • Proinflammatory cytokines stimulate catecholamine synthesis in ICCs. • NF-κB, HIF-1α and HDACs pathways are required for ICCs function. In a previous work using guinea pig prostate, we have identified a novel interstitial cells of Cajal (ICCs) which possess close contacts between sympathetic nerve bundles and smooth muscle cells. The ability of prostatic ICCs in mediating excitatory neural inputs was therefore studied using isolated murine prostate ICCs by collagenase digestion combined with FACS method. RT-PCR and Western blotting analyses revealed that prostatic ICCs under a quiescent state expressed abundantly the rate-limiting enzymes essential for catecholamine synthesis. Moreover, distinct proinflammatory cytokines (e.g. IL-1β, IL-8, ICAM-1 and TNF-α) could significantly stimulate the expression levels of the rate-limiting enzymes of catecholamine production in prostate ICCs. Mechanistically, the above-mentioned stimulatory effects of proinflammatory cytokines appeared to be mediated via activation of NF-κB, HIF-1α and HDACs signaling pathways. Considering that prostatic catecholamine overactivity serves as an essential etiology of pelvic pain by indirectly stimulating the smooth muscle cell proliferation, or by directly causing muscular spasm, our results collectively suggest that targeting the NF-κB, HIF-1α and HDACs pathways in prostate ICCs be considered as a new strategy for treatment of chronic pelvic pain syndrome (CPPS) induced by chronic prostatitis (CP). Overall, the current study should shed novel light on the biology of this unique prostate ICCs.

60 APPLIED LIFE SCIENCES↗

Overexpression of a repressor MdMYB15L negatively regulates anthocyanin and cold tolerance in red-fleshed callus

Highlights: • MdMYB15L inhibit the expression of MdCBF2 by binding its promoter. • MdMYB15L interact with MdbHLH33 via its bHLH binding sequence. • MdMYB15L weaken MdbHLH33-induced anthocyanin accumulation by interacting with MdbHLH33. The cold-induced metabolic pathway and anthocyanin biosynthesis play important roles in plant growth. In this study, we identified a bHLH binding motif in the MdMYB15L protein using protein sequence analyses. Yeast two-hybrid and pull-down assays showed that MdMYB15L could interact with MdbHLH33. Overexpressing MdMYB15L in red-fleshed callus inhibited the expression of MdCBF2 and resulted in reduced cold tolerance but did not affect anthocyanin levels. Chip-PCR and EMSA analysis showed that MdMYB15L could bind the type II cis-acting element found in the MdCBF2 promoter. Overexpressing MdMYB15L in red-fleshed callus overexpressing MdbHLH33 also reduced cold tolerance and reduced MdbHLH33-induced anthocyanin biosynthesis. Knocking out the bHLH binding sequence of MdMYB15L (LBSMdMYB15L) prevented LBSMdMYB15L from interacting with MdbHLH33. Overexpressing LBSMdMYB15L in red-fleshed callus overexpressing MdbHLH33 also reduced cold tolerance and reduced MdbHLH33-induced anthocyanin biosynthesis. Together, these results suggested that an apple repressor MdMYB15L might play a key role in the cold signaling and anthocyanin metabolic pathways.

60 APPLIED LIFE SCIENCES↗

MicroRNA-185 inhibits the growth and proliferation of osteoblasts in fracture healing by targeting PTH gene through down-regulating Wnt/β -catenin axis: In an animal experiment

Fracture healing is a repair process of a mechanical discontinuity loss of force transmission, and pathological mobility of bone. Increasing evidence suggests that microRNA (miRNA) could regulate chondrocyte, osteoblast, and osteoclast differentiation and function, indicating miRNA as key regulators of bone formation, resorption, remodeling, and repair. Hence, during this study, we established a right femur fracture mouse model to explore the effect microRNA-185 (miR-185) has on osteoblasts in mice during fracture healing and its underlying mechanism. After successfully model establishment, osteoblasts were extracted and treated with a series of mimics or inhibitors of miR-185, or siRNA against PTH. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot analysis were performed to determine the levels of miR-185, PTH, β-catenin and Wnt5b. Cell viability, cycle distribution and apoptosis were detected by means of MTT and flow cytometry assays. Dual luciferase reporter gene assay verified that PTH is a target gene of miR-185. Osteoblasts transfected with miR-185 mimics or siRNA against PTH presented with decreased levels of PTH, β-catenin and Wnt5b which indicated that miR-185 blocks the Wnt/β -catenin axis by inhibiting PTH. Moreover, miR-185 inhibitors promoted the osteoblast viability and reduced apoptosis with more cells arrested at the G1 stage. MiR-185 mimics were observed to have inhibitory effects on osteoblasts as opposed to those induced by miR-185 inhibitors. Above key results indicated that suppression of miR-185 targeting PTH could promote osteoblast growth and proliferation in mice during fracture healing through activating Wnt/β -catenin axis.

60 APPLIED LIFE SCIENCES↗

Down-regulation of TRAF4 targeting RSK4 inhibits proliferation, invasion and metastasis in breast cancer xenografts

Highlights: • Knockdown of TRAF4 inhibited the growth of xenograft tumors in nude mice. • Knockdown of TRAF4 significantly decreased the lung and liver metastases. • There is a negative correlation between TRAF4 and RSK4 mRNA and proteins. TRAF4 is interacting with RSK4 possibly by the induction of AKT/NF-κB signal axis. Ribosomal S6 protein kinase 4 (RSK4) was known as a novel tumor suppressor gene, and the tumor necrosis factor receptor-associated factor 4 (TRAF4) was linked to carcinogenesis. The purpose of this study is to further investigate the effect of the TRAF4 gene on cell proliferation, invasion and metastasis in vivo and explore whether there is an interaction between TRAF4 and RSK4 in breast cancer. MDA-MB-231 cells were transfected with lentivirus TRAF4-shRNA to specifically block the expression of TRAF4, or transfected with lentivirus negative-shRNA as a negative control. Four-six weeks female BALB/c nude mice were randomly assigned to three groups (n = 14): TRAF4-shRNA, negative and control, and then inoculated subcutaneously with the corresponding cells. In-vivo metastasis model was constructed by injecting above cells into tail vein. Tumor proliferation was assessed in terms of the tumor growth curve, tumor size and weight. Invasion and metastasis were evaluated by the histopathologic examination in lung or/and liver tissues. Measurement of TRAF4 and RSK4 expression and their correlation factors (AKT, NF-κB, TGF-β1, TNF-α, MMP2 and MMP9) were performed by immunohistochemistry, western blot or fluorescence quantitative RT-PCR. We found that the size and weight of tumors in TRAF4-shRNA group was significantly smaller than the negative and blank group, and the number of the lung and liver metastases lesions was also fewer (P < 0.05). And TRAF4 and its correlation factors (P-AKT, P-NF-κB, TGF-β1, TNF-α, MMP2 and MMP9) in the TRAF4-shRNA group were significantly decreased compared with the negative and blank group. However, the expression of RSK4 mRNA and protein in TRAF4-shRNA group were significantly increased. Collectively, TRAF4 knockdown significantly inhibited proliferation, invasion and metastasis in the xenograft nude mouse model, possibly involving in the interaction with RSK4 through down-regulation of AKT signaling pathway and then inactivating NF-κB pathway.

60 APPLIED LIFE SCIENCES↗

Detection of mycobacterial small RNA in the bacterial culture supernatant and plasma of patients with active tuberculosis

Bacterial small RNA (sRNA) has been shown to play an important role in control of bacteria virulence, stress response and physiological metabolism by post-transcriptional regulation of gene expression. However, there were few reports about bacterial sRNA as a biomarker of infection. To test the potential role of sRNA in indicating infection of Mycobacterium tuberculosis, total RNA were extracted from the filtrated bacterial cultural supernatant. After synthesis of cDNA by reverse transcription, four Mycobacterial sRNAs including ASdes, ASpks, AS1726, and AS1890, which have been experimentally confirmed by Kristine B in the year of 2009, were detected by real time PCR. The specificity was verified by sequencing of the amplified products. Moreover, we demonstrate that the presence of sRNA Asdes in plasma of 55.56% (15/27) TB patients and 25.00% (6/24) normal controls with BCG vaccination (P < 0.05). Our results suggest that bacterial non-coding sRNA can be detected from either bacterial culture supernatants or patient's plasma. Detecting of Mycobacterial sRNA provides a rapid and relatively noninvasive approach for diagnosing disease and could be developed as a biomarker to identify patients with active tuberculosis to help make informed decisions about proper therapies.

60 APPLIED LIFE SCIENCES↗

Circular RNA expression profiles in hippocampus from mice with perinatal glyphosate exposure

Glyphosate is the active ingredient in numerous herbicide formulations. The roles of glyphosate in embryo-toxicity and neurotoxicity have been reported in human and animal models. Recently, several studies have reported evidence linking neurodevelopmental disorders (NDDs) with gestational glyphosate exposure. However, the role of glyphosate in neuronal development is still not fully understood. Our previous study found that perinatal glyphosate exposure resulted in differential microRNA expression in the prefrontal cortex of mouse offspring. However, the mechanism of glyphosate-induced neurotoxicity in the developing brain is still not fully understood. Considering the pivotal role of Circular RNAs (circRNAs) in the regulation of gene expression, a circRNA microarray method was used in this study to investigate circRNA expression changes in the hippocampus of mice with perinatal glyphosate exposure. The circRNA microarrays revealed that 663 circRNAs were significantly altered in the perinatal glyphosate exposure group compared with the control group. Among them, 330 were significantly upregulated, and the other 333 were downregulated. Furthermore, the relative expression levels of mmu-circRNA-014015, mmu-circRNA-28128 and mmu-circRNA-29837 were verified using quantitative real-time polymerase chain reaction (qRT-PCR). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses demonstrated that stress-associated steroid metabolism pathways, such as aldosterone synthesis and secretion pathways, may be involved in the neurotoxicity of glyphosate. These results showed that circRNAs are aberrantly expressed in the hippocampus of mice with perinatal glyphosate exposure and play potential roles in glyphosate-induced neurotoxicity.

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