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Mounting evidence has shown that miRNA-150 expression is upregulated in gastric cancer (GC) and is associated with gastric carcinogenesis, but the underlying oncogenic mechanism remains elusive. Here, we discovered that miRNA-150 targets the tumor suppressor SUFU to promote cell proliferation, migration, and the epithelial–mesenchymal transition (EMT) via the dual activation of Hedgehog (Hh) and Wnt signaling. MiRNA-150 was highly expressed in GC tissues and cell lines, and the level of this miRNA was negatively related to that of SUFU. In addition, both the miRNA-150 and SUFU levels were associated with tumor differentiation. Furthermore, miRNA-150 activated GC cell proliferation and migration in vitro. We found that miRNA-150 inhibitors repressed not only Wnt signaling by promoting cytoplasmic β-catenin localization, but also repressed Hh signaling and EMT. MiRNA-150 inhibition also resulted in significant tumor volume reductions in vivo, suggesting the potential application of miRNA-150 inhibitors in GC therapy. The expression of genes downstream of Hh and Wnt signaling was also reduced in tumors treated with miRNA-150 inhibitors. Notably, anti-SUFU siRNAs rescued the inhibitory effects of miRNA-150 inhibitors on Wnt signaling, Hh activation, EMT, cell proliferation, cell migration, and colony formation. Taken together, these findings indicate that miRNA-150 is oncogenic and promotes GC cell proliferation, migration, and EMT by activating Wnt and Hh signaling via the suppression of SUFU expression.

Previous research has found that miRNA-20b is highly expressed in gastric cancer (GC), however, its function and underlying mechanism are not clear. Wnt signaling pathway, implicated in tumorigeneisis, is activated in more than 30% of GC. We would like to characterize the biological behavior of miRNA-20b in terms of modulating Wnt/β-catenin signaling and EMT. We showed that miRNA-20b inhibitors suppressed Topflash/Fopflash dependent luciferase activity and the β-catenin nuclear translocation, resulting in inhibition of Wnt pathway activity and EMT. SUFU, negatively regulating Wnt and Hedgehog signaling pathway, was proved to be targeted by miRNA-20b. Moreover, additional knockdown of SUFU alleviated the inhibitory effect on Wnt pathway activity, EMT, cell proliferation/migration and colony formation caused by miRNA-20b inhibition. In summary, miRNA-20b is an oncogenic miRNA and promoted cell proliferation, migration and EMT in GC partially by activating Wnt pathway via targeting SUFU., miRNA-20b, SUFU, EMT, Wnt/β-catenin.

Cathodic plasma electrolytic deposition (CPED) was applied to efficiently produce a thick ceramic coating with superior wear and corrosion resistance on aluminium alloy. Ceramic composite coatings were synthesized in a glycerin-carbamide-based electrolyte with and without zirconium nitrate, and their phase components, morphologies and compositions were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and energy disperse spectroscopy (EDS). The tribological behaviour and electrochemical corrosion resistance were also evaluated. The results show that Al3C4-Al2O3 and Al3C4-Al2O3-ZrO2 coatings with thicknesses of 65 μm and 50 μm, respectively, were produced by DC-powered CPED in only 7 min. Relative to the uncoated alloy, both coated samples exhibited a much lower friction coefficient and wear rate. The ZrO2 incorporated in the coating enhanced the hardness of the coating and dramatically decreased the friction coefficient to 22% of that of the uncoated alloy. The incorporation of ZrO2 also increased the brittleness, resulting in a slightly higher wear rate than that of the ZrO2-free coating. The wear mechanisms of the Al3C4-Al2O3-ZrO2 and ZrO2-free coatings were concluded to be fatigue failure and abrasive wear, respectively. Both coated samples exhibited improved corrosion resistance. The ZrO2 introduced in the coating also decreased the corrosion current density to only 2.7% of that of the Al3C4-Al2O3 coating and enhanced the capacitive loop and impedance.

A mounting body of evidence has revealed that microRNAs (miRs) serve pivotal roles in various developmental processes, and in tumourigenesis, by binding to target genes and subsequently regulating gene expression. Continued activation of the Wnt/β‑catenin signalling is positively associated with human malignancy. In addition, miR‑194 dysregulation has been implicated in gastric cancer (GC); however, the molecular mechanisms underlying the effects of miR‑194 on GC carcinogenesis remain to be elucidated. The present study demonstrated that miR‑194 was upregulated in GC tissues and SUFU negative regulator of Ηedgehog signaling (SUFU) was downregulated in GC cell lines. Subsequently, inhibition of miR‑194 attenuated nuclear accumulation of β‑catenin, which consequently blocked Wnt/β‑catenin signalling. In addition, the cytoplasmic translocation of β‑catenin induced by miR‑194 inhibition was mediated by SUFU. Furthermore, genes associated with the Wnt/β‑catenin signalling pathway were revealed to be downregulated following inhibition of the Wnt signalling pathway by miR‑194 suppression. Finally, the results indicated that cell apoptosis was markedly increased in response to miR‑194 inhibition, strongly suggesting the carcinogenic effects of miR‑194 in GC. Taken together, these findings demonstrated that miR‑194 may promote gastric carcinogenesis through activation of the Wnt/β‑catenin signalling pathway, making it a potential therapeutic target for GC.

SMG‐1,a member of the phosphoinositide kinase‐like kinase family, functioned as a tumor suppressor gene. However, the role of SMG‐1 in GC remain uncharacterized. In this study, regulation of SMG‐1 by miR‐192 and‐215, along with the biological effects of this modulation, were studied in GC. We used gene microarrays to screening and luciferase reporter assays were to verify the potential targets of miR‐192 and‐215. Tissue microarrays analyses were applied to measure the levels of SMG‐1 in GC tissues. Western blot assays were used to assess the signaling pathway of SMG‐1 regulated by miR‐192 and‐215 in GC. SMG‐1 was significantly downregulated in GC tissues.The proliferative and invasive properties of GC cells were decreased by inhibition of miR‐192 and‐215, whereas an SMG‐1siRNA rescued the inhibitory effects. Finally, SMG‐1 inhibition by miR‐192 and‐215 primed Wnt signaling and induced EMT. Wnt signaling pathway proteins were decreased markedly by inhibitors of miR‐192 and‐215, while SMG‐1 siRNA reversed the inhibition apparently. Meanwhile, miR‐192 and‐215 inhitibtors increased E‐cadherin expression and decreased N‐cadherin and cotransfection of SMG‐1 siRNA reversed these effects. In summary, these findings illustrate that SMG‐1 is suppressed by miR‐192 and‐215 and functions as a tumor suppressor in GC by inactivating Wnt signaling and suppressing EMT.

To solve the problem of rapid degradation for magnesium-based implants, surface modification especially coating method is widely studied and showed the great potential for clinical application. However, as concerned to the further application and medical translation for biodegradable magnesium alloys, there are still lack of data and comparisons among different coatings on their degradation and biological properties. This work studied three commonly used coatings on Mg-Sr alloy, including micro-arc oxidation coating, electrodeposition coating and chemical conversion coating, and compared these coatings for requirements of favorable degradation and biological performances, how each of these coating systems has performed. Finally the mechanism for the discrepancy between these coatings is proposed. The results indicate that the micro-arc oxidation coating on Mg-Sr alloy exhibited the best corrosion resistance and cell response among these coatings, and is proved to be more suitable for the orthopedic application.

Magnesium-based metals are considered as promising biodegradable orthopedic implant materials due to their potentials of enhancing bone healing and reconstruction, and in vivo absorbable characteristic without second operation for removal. However, the rapid corrosion has limited their clinical applications. Ca-P coating by electrodeposition has been supposed to be effective to control the degradation rate and enhance the bioactivity. In this work, a brushite coating was fabricated on the Mg-Sr alloy by pulse electrodeposition (PED) to evaluate its efficacy for orthopedic application. Interestingly, an inner corrosion layer was observed between the PED coating and the alloy substrate. Meanwhile the results of in vitro immersion and electrochemical tests showed that the corrosion resistance of the coated alloy was undermined in comparison with the uncoated alloy. It was deduced that the existence of this corrosion layer was attributed to the worse corrosion performance of the alloy. The mechanism on formation of the inner corrosion layer and its influence on consequent degradation were analyzed. It can be concluded that the electrodeposition coating should be not suitable for those magnesium alloys with poor corrosion resistance such as the Mg-Sr alloy. More importantly, it should be noted that the process of coating formation combined with the nature of substrate alloy is important to evaluate the efficacy of coating for biodegradable Mg-based implants application.

Considering the compatibility between degradation and bioactivity of magnesium-based implants for bone repair, micro-arc oxidation is used to modify the magnesium alloy surface in aqueous electrolytes, allowing strontium, calcium, and phosphorus to be incorporated into the coating. The thickness, composition, morphology and phase of this Sr–Ca–P containing coating are characterized by scanning electron microscopy equipped with energy dispersive X-ray spectrometer and X-ray diffraction. The in vitro and in vivo degradation of the coating is evaluated by immersion test, electrochemical test and implantation test. Moreover, the cytocompatibility is tested with osteoblast cell according to ISO 10993. The results show that Sr, Ca and P elements are incorporated into the oxide coating, and a refined structure with tiny discharging micro-pores is observed on the surface of the coating. The Sr–Ca–P coating possesses a better corrosion resistance in vitro and retards the degradation in vivo. Such coating is expected to have significant medical applications on orthopedic implants and bone repair materials.

A new phenylethanoid glycoside (2) and a new secoiridoid glycoside (16) were isolated from the leaves of Ligustrum purpurascens together with fourteen known compounds (1 and 3–15). The structures of the new compounds were determined by spectroscopic analyses (UV, IR, HR-ESI-MS, 1D, and 2D NMR). The absolute configuration of 16 was further determined by CD analysis. All phenylethanoid glycosides were prepared and their up-regulation of IFN-γ production in mouse splenic lymphocytes was evaluated. Compounds 1, 5, 6, 10, 11, 13 and 15 exhibited potent stimulatory effect on IFN-γ secretion.

Controlling the corrosion rate of magnesium alloys in vivo to match the bone repair is crucially important for application as biodegradable orthopedic implants. To solve this challenge, a Si-doped Ca-P coating with a novel dual-layer structure was deposited on AZ31 alloy substrate by pulse electrodeposition. The morphology, composition and formation of dual-layer coating were believed to be determined by pulse electrodeposition parameters, thus the deposition time, temperature, duty cycle, pH value of the electrolyte and the standing duration of mixed electrolyte were regulated to seek possible influences and mechanism on the coating formation. Weight gain and pH monitoring tests were also used to evaluate the performance of coating under the varied parameters. The results indicated that deposition temperature and time remarkably influenced the morphology, homogeneity and crystallinity of Ca-P coating. A uniform and compact coating with better degradation performance was obtained at 60 degrees C with deposition time of 40 min. The shorter standing duration of the electrolyte lead to an incomplete coating and uneven distribution of Si contents. The two coupled deposition models contributed to this dual-layer structure of Si-doped Ca-P coating and possible formation mechanism was proposed. (C) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Exploring novel anticancer agents that can trigger non-apoptotic or non-autophagic cell death is urgent for cancer treatment. In this study, we screened and identified an unexplored anticancer activity of gypenoside L (Gyp-L) isolated from Gynostemma pentaphyllum. We showed that treatment with Gyp-L induces non-apoptotic and non-autophagic cytoplasmic vacuolation death in human hepatocellular carcinoma (HCC) cells. Mechanically, Gyp-L initially increased the intracellular reactive oxygen species (ROS) levels, which, in turn, triggered protein ubiquitination and unfolded protein response (UPR), resulting in Ca(2+) release from endoplasm reticulum (ER) inositol trisphosphate receptor (IP3R)-operated stores and finally cytoplasmic vacuolation and cell death. Interruption of the ROS-ER-Ca(2+) signaling pathway by chemical inhibitors significantly prevented Gyp-L-induced vacuole formation and cell death. In addition, Gyp-L-induced ER stress and vacuolation death required new protein synthesis. Overall, our works provide strong evidence for the anti-HCC activity of Gyp-L and suggest a novel therapeutic option by Gyp-L through the induction of a unconventional ROS-ER-Ca(2+)-mediated cytoplasmic vacuolation death in human HCC.

Lipopolysaccharide (LPS) can exacerbate asthma; however, the mechanisms are not fully understood. This study investigated the effect of LPS on antigen-stimulated mast cell degranulation and the underlying mechanisms. We found that LPS enhanced degranulation in RBL-2H3 cells and mouse peritoneal mast cells upon FceRI activation, in a dose- and time-dependent manner. Parallel to the alteration of degranulation, LPS increased FceRI-activated Ca(2+) mobilization, as well as Ca(2+) entry through store-operated calcium channels (SOCs) evoked by thapsigargin. Blocking Ca(2+) entry through SOCs completely abolished LPS enhancement of mast cell degranulation. Consistent with functional alteration of SOCs, LPS increased mRNA and protein levels of Orai1 and STIM1, two major subunits of SOCs, in a time-dependent manner. In addition, LPS increased the mRNA level of Toll-like receptor 4 (TLR4) in a time-dependent manner. Blocking TLR4 with Cli-095 inhibited LPS, increasing transcription and expression of SOC subunits. Concomitantly, the effect of LPS enhancement of Ca(2+) mobilization and mast cell degranulation was largely reduced by Cli-095. Administration of LPS (1 μg) in vivo aggravated airway hyperreactivity and inflammatory reactions in allergic asthmatic mice. Histamine levels in serum and bronchoalveolar lavage fluid were increased by LPS treatment. In addition, Ca(2+) mobilization was enhanced in peritoneal mast cells isolated from LPS-treated asthmatic mice. Taken together, these results imply that LPS enhances mast cell degranulation, which potentially contributes to LPS exacerbating allergic asthma. Lipopolysaccharide increases Ca(2+) entry through SOCs by upregulating transcription and expression of SOC subunits, mainly through interacting with TLR4 in mast cells, resulting in enhancement of mast cell degranulation upon antigen stimulation.

A silicon doped calcium phosphate coating was obtained successfully on AZ31 alloy substrate via pulse electrodeposition. A novel dual-layer structure was observed with a porous lamellar-like and outer block-like apatite layer. In vitro immersion tests were adopted in simulated body fluid within 28 days of immersion. Slow degradation rate obtained from weight loss was observed for the Si-doped Ca-P coating, which was also consistent with the results of electrochemical experiments showing an enhanced corrosion resistance for the coating. Further formation of an apatite-like layer on the surface after immersion proved better integrity and biomineralization performance of the coating. Biological characterization was carried out for viability, proliferation and differentiation of MG63 osteoblast-like cells. The coating showed a good cell growth and an enhanced cell proliferation. Moreover, an increased activity of osteogenic marker ALP was found. All the results demonstrated that the Si-doped calcium phosphate was perspective to be used as a coating for magnesium alloy implants to control the degradation rate and enhance the bioactivity, which would facilitate the rapidity of bone tissue repair.

The behavioral and neuroendocrine reactivity to a novel environment (open field) and the adrenocorticotropic hormone (ACTH)/corticosterone response to a corticotropin-releasing factor (CRF) challenge were measured in 2-mo-old rats from four inbred strains derived from the Wistar-Kyoto rat: spontaneously hypertensive rats (SHRs), hypertensive and behaviorally hyperactive to novelty; WKY, neither hypertensive nor hyperactive; WKHA, hyperactive but normotensive; and WKHT, only hypertensive. The ACTH response to CRF was much lower in SHRs than WKYs, this reduced reactivity being clearly associated with the hyperactivity trait, since it was present in the WKHA and absent in the WKHT strain. On the other hand, the ACTH/corticosterone response to a psychological stimulus (open field) could not clearly discriminate the four strains. The largest difference was found in the prolactin response. Post-open-field levels were much lower in the WKHA (27.11 +/- 4.69 ng/ml) than in the parent WKY strain (83.65 +/- 6.84 ng/ml), the hypertensive strains having intermediate levels (WKHT: 58.05 +/- 7.65 ng/ml; SHR: 64.13 +/- 7.19 ng/ml). Other differences were also found in the levels of aldosterone and renin activity. These results indicate that these strains are an excellent model to study neuroendocrine correlates of hypertension and hyperactivity, which are associated in the SHR strain and may be of interest for the study of the association between neuroendocrine and behavioral characteristics.

Background Esophageal cancer ranks eighth among frequent cancers worldwide. Our aim was to investigate whether and at which neoplastic stage promoter hypermethylation of CAV1 is involved in human esophageal carcinogenesis. Methods Using real-time quantitative methylation-specific PCR (qMSP), we examined CAV1 promoter hypermethylation in 260 human esophageal tissue specimens. Real-time RT-PCR and qMSP were also performed on OE33 esophageal cancer cells before and after treatment with the demethylating agent, 5-aza-2’-deoxycytidine (5-Aza-dC). Results CAV1 hypermethylation showed highly discriminative ROC curve profiles, clearly distinguishing esophageal adenocarcinomas (EAC) and esophageal squamous cell carcinomas (ESCC) from normal esophagus (NE) (EAC vs. NE, AUROC = 0.839 and p