Extracellular vesicles containing circMYBL1 induce CD44 in adenoid cystic carcinoma cells and pulmonary endothelial cells to promote lung metastasis.

Adenoid cystic carcinoma (ACC) is a rare malignant epithelial neoplasm that arises in secretory glands and commonly metastasizes to the lungs. MYBL1 is frequently overexpressed in ACC and has been suggested to be a driver of the disease. Here, we identified a circRNA derived from MYBL1 pre-mRNA that accompanied overexpression of MYBL1 in ACC. Overexpression of circMYBL1 was correlated with increased lung metastasis and poor overall survival in ACC patients. Ectopic circMYBL1 overexpression promoted malignant phenotypes and lung metastasis of ACC cells. Mechanistically, circMYBL1 formed a circRNA-protein complex with CCAAT enhancer binding protein beta (CEBPB), which inhibited ubiquitin-mediated degradation and promoted nuclear translocation of CEBPB. In the nucleus, circMYBL1 increased the binding of CEBPB to the CD44 promoter region and enhanced its transcription. In addition, circMYBL1 was enriched in small extracellular vesicles (sEVs) isolated from the plasma of ACC patients. Treatment with sEVs containing circMYBL1 in sEVs enhanced pro-metastatic phenotypes of ACC cells, elevated the expression of CD44 in human pulmonary microvascular endothelial cells (HPMECs), and enhanced the adhesion between HPMECs and ACC cells. Moreover, circMYBL1 encapsulated in sEVs increased the arrest of circulating ACC cells in the lung and enhanced the lung metastatic burden. This data suggests that circMYBL1 is a tumor-promoting circRNA that could serve as a potential biomarker and therapeutic target in ACC.

ALMS1-IT1: A Key Player in the Novel Disulfidptosis-Related LncRNA Prognostic Signature for Head and Neck Squamous Cell Carcinoma.

Disulfidptosis is a newly discovered form of programmed cell death that is induced by disulfide stress. It is closely associated with various cancers, including head and neck squamous cell carcinoma (HNSCC). However, the factors involved in the modulation of disulfidptosis-related genes (DRGs) still remain unknown. In this study, we established and validated a novel risk score model composed of 11 disulfidptosis-related lncRNAs (DRLs) based on 24 DRGs in HNSCC. The results revealed strong correlations between the 11-DRL prognostic signature and clinicopathological features, immune cell infiltration, immune-related functions, and disulfidptosis-associated pathways, including NADPH and disulfide oxidoreductase activities. Furthermore, we studied and verified the involvement of ALMS1-IT1, one of the 11 model DRLs, in the disulfidptosis of HNSCC cell lines. A series of assays demonstrated that ALMS1-IT1 modulated cell death under starvation conditions in a pentose phosphate pathway (PPP)-dependent manner. Knockdown of ALMS1-IT1 inhibited the PPP, contributing to a decline in NADPH levels, which resulted in the formation of multiple intermolecular disulfide bonds between actin cytoskeleton proteins and the collapse of F-actin in the cytoplasm. Therefore, ALMS1-IT1, which is highly expressed in SLC7A11high cells, can be considered a promising therapeutic target for disulfidptosis-focused treatment strategies for cancer and other diseases.

NAT10/CEBPB/vimentin signalling axis promotes adenoid cystic carcinoma malignant phenotypes in vitro.

OBJECTIVE: To explore the biological function and mechanisms of CEBPB and NAT10-mediated N4-acetylcytidine (ac4c) modification in salivary adenoid cystic carcinoma (SACC). MATERIALS AND METHODS: CEBPB and NAT10 were knocked down in SACC-LM cells by siRNA transfection and overexpressed in SACC-83 cells by plasmid transfection. Malignant phenotypes were evaluated using CCK-8, Transwell migration and colony formation assays. Real-time PCR, western blotting, ChIP and acRIP were used to investigate the molecular mechanisms involved. RESULTS: We found that CEBPB was highly expressed in SACC tissues and correlated with lung metastasis and unfavourable prognosis. Gain- and loss-of-function experiments revealed that CEBPB promoted SACC malignant phenotypes. Mechanistically, CEBPB exerted its oncogenic effect by binding to the vimentin gene promoter region to enhance its expression. Moreover, NAT10-mediated ac4c modification led to stabilization and overexpression of CEBPB in SACC cells. We also found that NAT10, the only known human enzyme responsible for ac4C modification, promoted SACC cell migration, proliferation and colony formation. Moreover, CEBPB overexpression restored the inhibitory effect of NAT10 knockdown on malignant phenotypes. CONCLUSIONS: Our study reveals the critical role of the newly identified NAT10/CEBPB/vimentin axis in SACC malignant progression, and the findings may be applied to improve treatment for SACC.

Long non-coding RNA MRPL23-AS1 suppresses anoikis in salivary adenoid cystic carcinoma in vitro.

Distant lung metastasis is the main factor that affects the survival rate of patients with salivary adenoid cystic carcinoma (SACC). Anoikis resistance is a feature of tumor cells that easily metastasize. The long non-coding RNA (lncRNA) MRPL23 antisense RNA 1 (MPRL23-AS1) is related to lung metastasis in SACC, but its role in anoikis resistance is unknown. After altering MPRL23-AS1 expression in SACC cells, anoikis resistance was detected by calcein AM/PI staining and annexin V/PI flow cytometry. The apoptosis marker activated caspase-3 and the bcl-2/bax ratio were detected by Western blotting. The relationship between MPRL23-AS1 and the promoter of the potential downstream target gene p19INK4D was identified by chromatin immunoprecipitation (ChIP)-PCR assay. p19INK4D expression in patient tissues was determined using qRT-PCR and immunohistochemistry. The functional experiments showed that MPRL23-AS1 could promote anoikis resistance in vitro. MRPL23-AS1 recruited the EZH2 to the promoter region of p19INK4D, inhibited p19INK4D expression, and promoted tumor cell anoikis resistance. p19INK4D overexpression did not affect anoikis in attached cells; however, it attenuated the anoikis resistance effect of MPRL23-AS1 in suspension cells. p19INK4D expression was significantly lower in SACC tissues than in normal tissues. The novel MRPL23-AS1/p19INK4D axis may be a potential SACC biomarker or therapeutic target.

In-situ formed elastin-based hydrogels enhance wound healing via promoting innate immune cells recruitment and angiogenesis.

Harnessing the inflammation and angiogenesis is extremely important in wound healing. In this study, we developed bioactive elastin-based hydrogels which can recruit and modulate the innate immune cells and accelerate angiogenesis in the wound site and subsequently improve wound regeneration. These hydrogels were formed by visible-light cross-linking of acryloyl-(polyethylene glycol)-N-hydroxysuccinimide ester modified elastin with methacrylated gelatin, in order to mimic dermal microenvironment. These hydrogels showed highly tunable mechanical properties, swelling ratios and enzymatic degradation profiles, with moduli within the range of human skin. To mimic the in vivo degradation of the elastin by elastase from neutrophils, in vitro co-culture of the hydrogels and neutrophils was conducted. The derived conditioned medium containing elastin derived peptides (EDP-conditioned medium) promoted the expression of both M1 and M2 markers in M1 macrophages in vitro. Additionally, the EDP-conditioned medium induced superior tube formation of endothelia cells in Matrigel. In mice wound model, these elastin-based hydrogels attracted abundant neutrophils and predominant M2 macrophages to the wound and supported their infiltration into the hydrogels. The outstanding immunomodulatory effect of the elastin-based hydrogels resulted in superior angiogenesis, collagen deposition and dermal regeneration. Hence, these elastin-based hydrogels can be a promising regenerative platform to accelerate wound repair.

[Application of keratinocytes derived from human embryonic stem cells for toxicological evaluation of drugs].

PURPOSE: To preliminarily explore the cytotoxicological responses of keratinocytes derived from human embryonic stem cells(K-hESCs) to drugs, and to provide a basis for the establishment of a new biosafety evaluation model. METHODS: CCK-8 assay was used to detect cell viability and cytotoxicity. The detection of pharmacological response was observed and compared when K-hESCs directly derived from human embryonic stem cells, human gingival epithelial cells (HGECs), and human immortalized oral epithelial cells (HIOECs) were treated with retinoic acid (RA), 5-fluorouracil(5-FU), dexamethasone(DEX), and penicillin G(PG). Statistical analysis was performed using SPSS 16.0 software package. RESULTS: After drugs were applied to HGECs, HIOEC and K-hESCs, the half inhibitory concentrations (IC50) of RA was 6.1±0.03, 5.62±0.05 and 6.58±0.02, respectively. The IC50 of 5-FU was 1.65±0.02，3.00±0.02 and 1.72±0.04, respectively. The IC50 of DEX was 113.67±0.014，328±0.002 and 126.17±0.05, respectively. The IC50 of PG was 2200±1.34，3795±2.42 and 2880±1.5, respectively. The IC50 of the four drugs between HIOEC and HGECs had significant differences(P<0.05), but there was no significant difference in IC50 between K-hESCs and HGECs(P>0.05). The IC50 of K-hESCs and HIOEC also had significant differences(P<0.05). CONCLUSIONS: IC50 of K-hESCs was closer to HGECs than HIOEC. It was speculated that K-hESCs could simulate the response of normal human cells in cytotoxicity study.

MicroRNA­103a­3p promotes metastasis by targeting TPD52 in salivary adenoid cystic carcinoma.

Salivary adenoid cystic carcinoma (SACC) exhibits slow continuous growth, frequent local recurrences and a high incidence of blood metastasis, with advanced lung metastasis frequently occurring and being among the primary causes of mortality. MicroRNAs (miR) serve a significant role in the initiation and development of cancer and may be tumour­specific molecular targets. However, the role of miR­103a­3p in SACC remains largely unknown. In the present study, the expression levels of miR­103a­3p and tumour protein D52 (TPD52) were detected by reverse transcription­quantitative PCR. In addition, wound­healing assays, Transwell assays and mouse models of lung metastasis were used to investigate the biological functions exerted by miR­103a­3p. The present results suggested that miR­103a­3p expression was significantly upregulated in SACC samples. Gain­of­function and loss­of­function studies in SACC cells demonstrated that miR­103a­3p acted as an oncogene by promoting tumour cell migration in vitro and lung metastasis in vivo. Dual­luciferase reporter gene assays indicated that miR­103a­3p exerted its regulatory functions by binding to the 3' untranslated region of TPD52 mRNA. TPD52 overexpression rescued the effect of miR­103a­3p on promoting SACC cell migration, suggesting that miR­103a­3p acted as an oncogene to promote cancer metastasis by directly targeting TPD52. Thus, the newly identified miR­103a­3p/TPD52 axis contributes to the understanding of SACC pathogenesis, providing insights into the identification of novel biomarkers or potential therapeutic targets in SACC.

Long Noncoding RNA MRPL23-AS1 Promotes Adenoid Cystic Carcinoma Lung Metastasis.

Lung metastasis is a major factor affecting long-term survival in patients with adenoid cystic carcinoma. Here, we showed that the long noncoding RNA (lncRNA) MRPL23 antisense RNA 1 (MRPL23-AS1) was highly expressed and correlated with lung metastasis and overall survival in patients with salivary adenoid cystic carcinoma (SACC). MRPL23-AS1 positively regulated epithelial-mesenchymal transition by forming an RNA-protein complex with enhancer of zeste homolog 2 (EZH2). MRPL23-AS1 increased the binding of EZH2 and H3K27me3 on the E-cadherin promoter region. Moreover, MRPL23-AS1 levels were higher in exosomes isolated from the blood plasma of patients with SACC, and exosomal MRPL23-AS1 affected pulmonary microvascular endothelial cells in an "exosomecrine" manner. MRPL23-AS1-enriched exosomes increased microvascular permeability and facilitated the metastasis of SACC in vivo. Collectively, these findings highlight a molecular mechanism of lung metastasis in SACC. MRPL23-AS1 may represent a biomarker and target for clinical intervention to control this intractable disease. SIGNIFICANCE: This study identifies a novel metastasis-promoting lncRNA MRPL23-AS1, which mediates the transcriptional silencing of E-cadherin through forming an RNA-protein complex with EZH2.

A Location Privacy Attack Based on the Location Sharing Mechanism with Erroneous Distance in Geosocial Networks.

Geographical social networks (GSN) is an emerging research area. For example, Foursquare, Yelp, and WeChat are all well-known service providers in this field. These applications are also known as location-based services (LBS). Previous studies have suggested that these location-based services may expose user location information. In order to ensure the privacy of the user's location data, the service provider may provide corresponding protection mechanisms for its applications, including spatial cloaking, fuzzy location information, etc., so that the user's real location cannot be easily cracked. It has been shown that if the positioning data provided by the user is not accurate enough, it is still difficult for an attacker to obtain the user's true location. Taking this factor into consideration, our attack method is divided into two stages for the entire attack process: (1) Search stage: cover the area where the targeted user is located with unit discs, and then calculate the minimum dominating set. Use the triangle positioning method to find the minimum precision disc. (2) Inference phase: Considering the existence of errors, an Error-Adjusted Space Partition Attack Algorithm (EASPAA) was proposed during the inference phase. Improved the need for accurate distance information to be able to derive the user's true location. In this study, we focus on the Location Sharing Mechanism with Maximal Coverage Limit to implement the whole attack. Experimental results show that the proposed method still can accurately infer the user's real location even when there is an error in the user's location information.

Stem cells  from exfoliated  deciduous  teeth alleviate hyposalivation caused by Sjögren syndrome.

OBJECTIVES: To evaluate the effect of stem cells  from  exfoliated  deciduous  teeth on the hyposalivation caused by Sjögren syndrome (SS) and investigate the mechanism. METHODS: Stem cells were injected into the tail veins of non-obese diabetic mice, the animal model of SS. The saliva flow was measured after pilocarpine intraperitoneal injection. Apoptosis and autophagy were evaluated by TUNEL and Western blot. Lymphocyte proportions were detected by flow cytometer. RESULTS: Fluid secretion was decreased in 21-week-old mice. Stem cell treatment increased fluid secretion, alleviated inflammation in the submandibular glands and reduced inflammatory cytokine levels in the serum, submandibular glands and saliva. Stem cells decreased the apoptotic cell number and the expressions of ATG5 and Beclin-1 in the submandibular glands. Stem cells have no effect on other organs. Furthermore, the infused stem cells migrated to the spleen and liver, not the submandibular gland. Stem cells directed T cells towards Treg cells and suppressed Th1 and Tfh cells in spleen lymphocytes. CONCLUSION: Stem cells  from  exfoliated  deciduous  teeth alleviate the hyposalivation caused by SS via decreasing the inflammatory cytokines, regulating the inflammatory microenvironment and decreasing the apoptosis and autophagy. The stem cells regulated in T-cell differentiation are involved in the immunomodulatory effects.

MYB promotes the growth and metastasis of salivary adenoid cystic carcinoma.

The incidence of recurrent t(6;9) translocation of the MYB proto­oncogene to NFIB (the gene that encodes nuclear factor 1 B­type) in adenoid cystic carcinoma (ACC) tumour tissues is high. However, MYB [the gene that encodes transcriptional activator Myb (MYB)] overexpression is more common, indicating that MYB serves a key role in ACC. The current study aimed to investigate the role of MYB in salivary (S)ACC growth and metastasis. A total of 50 fresh­frozen SACC tissues and 41 fresh­frozen normal submandibular gland (SMG) tissues were collected to measure MYB mRNA expression, and to analyse the associations between MYB and epithelial­mesenchymal transition (EMT) markers. Compared with normal SMG tissue, SACC tissues demonstrated significantly increased MYB expression, with a high expression rate of 90%. Interestingly, MYB tended to be negatively correlated with CDH1 [the gene that encodes cadherin­1 (E­cadherin)] and positively correlated with VIM (the gene that encodes vimentin), suggesting that MYB is associated with SACC metastasis. To explore the role of MYB in SACC, the authors stably overexpressed and knocked down MYB in SACC cells. The authors of the current study demonstrated that MYB overexpression promoted SACC cell proliferation, migration and invasion, whereas its knockdown inhibited these activities. Additionally, when MYB was overexpressed, CDH1 expression was downregulated, and CDH2 (the gene that encodes cadherin­2), VIM and ACTA2 (the gene that encodes actin, aortic smooth muscle) expression was upregulated. Then, the effect of MYB on lung tumour metastasis was investigated in vivo in non­obese diabetic/severe combined immunodeficiency mice. MYB overexpressing and control cells were injected into the mice through the tail vein. The results revealed that MYB promoted SACC lung metastasis. Collectively, these results demonstrated that MYB is aberrantly overexpressed in SACC tissues, and promotes SACC cell proliferation and metastasis, indicating that MYB may be a novel therapeutic target for SACC.

ß-adrenoceptor activation increased VAMP-2 and syntaxin-4 in secretory granules are involved in protein secretion of submandibular gland through the PKA/F-actin pathway.

Autologous submandibular gland transplantation is an effective treatment for severe dry eye syndrome. However, the protein secretion in transplanted gland is altered by a mechanism that remains to be elucidated. In the present study, we found that ß1-adrenoceptor (ß1-AR) and ß2-AR expression and the phosphorylation of the downstream molecule protein kinase A (PKA) were elevated in transplanted submandibular glands obtained from epiphora patients. Synaptobrevin/vesicle-associated membrane protein 2 (VAMP-2) interacted with syntaxin-4 and actin in human submandibular gland. The contents of syntaxin-4 and actin interacting with VAMP-2 were increased in transplanted gland. Moreover, VAMP-2 and syntaxin-4 expression in the secretory granule fraction, and VAMP-2 expression in the membrane protein fraction were increased in isoproterenol-treated and transplanted glands. Isoproterenol increased F-actin polymerization in the apical and lateral regions of the cytoplasm in both control and transplanted glands. Inhibiting PKA activity and/or F-actin formation abolished the isoproterenol-enhanced expression of VAMP-2 and syntaxin-4 in the secretory granule fraction and the isoproterenol-enhanced expression of VAMP-2 in the membrane protein fraction. Taken together, these results indicate that the activation of ß-ARs induces secretory granules and cell membrane fusion via the interaction of VAMP-2 and syntaxin-4 in a PKA- and F-actin-dependent manner in human submandibular gland. Up-regulated ß-ARs might participate in altering protein secretion in transplanted submandibular gland by promoting the interaction of VAMP-2 with syntaxin-4.

Hsa_circRNA_0059655 plays a role in salivary adenoid cystic carcinoma by functioning as a sponge of miR-338-3p.

Circular RNAs(circRNA) are recently demonstrated to have a close relationship with tumors.To investigate the role of circular RNA in the pathogenesis of salivary adenoid cystic carcinoma(SACC), ten SACC tissues and paired normal submandibular gland(SMG) tissues were collected as the tumor group and the control group. Total RNA was extracted and then measured using ceRNA microarray (including mRNA, lncRNA, and circRNA) and miRNA microarray. Gene Ontology(GO) analysis and Kyoto Encyclopedia of Gene and Genomes (KEGG) pathway analysis were performed in order to investigate the function of the differential expressing genes. The ceRNA regulatory network was constructed to find the core circRNAs. Then the role of circRNA on proliferation was examined in the SACC cell line SACC-83 using CCK-8,qRT-PCR and western blotting, and its roles on migration and invasion were examined using wound healing assay and transwell assay. The results of the microarrays showed that 3792 mRNAs, 7649 lncRNAs, 11553 circRNAs, and 132 miRNAs expressed differentially. The ceRNA regulatory network analysis showed that hsa_circ_0059655 and other 14circRNAs derived from PYGB target on several similar genes by miR-338-3p.Among the 15 circRNAs derived from PYGB, hsa_circ_0059655has the most relationships in the ceRNA network. Furthermore, after hsa_circ_0059655 was knocked down in SACC-83 cells, the expression of hsa-miR-338-3p was up-regulated while CCND1was down-regulated. The proliferation, migration, and invasion of SACC-83 cells also decreased after hsa_circ_0059655 knock-downed.Taken together, the circRNAs derived from PYGB may regulate the tumorigenesis and development of SACC through competing with miR-338-3p.

Ca2+-CaMKKß pathway is required for adiponectin-induced secretion in rat submandibular gland.

Adiponectin functions as a promoter of saliva secretion in rat submandibular gland via activation of adenosine monophosphate-activated protein kinase (AMPK) and increased paracellular permeability. Ca2+ mobilization is the primary signal for fluid secretion in salivary acinar cells. However, whether intracellular Ca2+ mobilization is involved in adiponectin-induced salivary secretion is unknown. Here, we found that full-length adiponectin (fAd) increased intracellular Ca2+ and saliva secretion in submandibular glands. Pre-perfusion with ethylene glycol-bis (2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA) combined with thapsigargin (TG), an endoplasmic reticulum Ca2+-ATPase inhibitor, abolished fAd-induced salivary secretion, AMPK phosphorylation, and enlarged tight junction (TJ) width. Furthermore, in cultured SMG-C6 cells, co-pretreatment with EGTA and TG suppressed fAd-decreased transepithelial electrical resistance and increased 4-kDa FITC-dextran flux responses. Moreover, fAd increased phosphorylation of calcium/calmodulin-dependent protein kinase (CaMKKß), a major kinase that is activated by elevated levels of intracellular Ca2+, but not liver kinase B1 phosphorylation. Pre-perfusion of the isolated gland with STO-609, an inhibitor of CaMKKß, abolished fAd-induced salivary secretion, AMPK activation, and enlarged TJ width. CaMKKß shRNA suppressed, whereas CaMKKß re-expression rescued fAd-increased paracellular permeability. Taken together, these results indicate that adiponectin induced Ca2+ modulation in rat submandibular gland acinar cells. Ca2+-CaMKKß pathway is required for adiponectin-induced secretion through mediating AMPK activation and increase in paracellular permeability in rat submandibular glands.

Epiregulin Promotes Lung Metastasis of Salivary Adenoid Cystic Carcinoma.

Salivary adenoid cystic carcinoma (SACC) is a peculiar malignant tumor, characterized by its slow but inexorable growth, with a high incidence of lung metastasis and poor prognosis. Here, we show the upregulated expression of EGFR ligand epiregulin in a subset of SACC cells correlates with lung metastasis and unfavorable outcome in patients with SACC. We found that upregulation of epiregulin in SACC cells induced epithelial-mesenchymal transition by regulating GLI1/E-cadherin. Elevated epiregulin increased the expression of pro-angiogenic factors, such as VEGFA, bFGF, and IL-8. We also show that epiregulin can be delivered via exosomes and was enriched in exosomes derived from epiregulin-overexpressing SACC cells. Furthermore, treating immunodeficient mice with these epiregulin-enriched exosomes greatly enhanced SACC metastasis to lung. These epiregulin-enriched exosomes significantly enhanced angiogenesis in the neighboring tumor microenvironment and increased vascular permeability in the pre-metastatic lung microenvironment in vivo. Therefore, epiregulin, as well as epiregulin-containing exosomes, may be a novel target for controlling SACC lung metastasis.

Decreased interaction between ZO-1 and occludin is involved in alteration of tight junctions in transplanted epiphora submandibular glands.

Tight junctions (TJs) in salivary epithelium play an important role in regulating saliva secretion. Autologous transplantation of submandibular glands (SMGs) is an effective method to treat severe dry eye syndrome. However, epiphora occurs in some patients 6 months after transplantation. We previously found that the acinar TJs are enlarged in rabbit SMGs after long-term transplantation, but the exact TJ components involved in the epiphora are still unknown. Here, we found that the mRNA and protein expression of ZO-1 and occludin were increased in the transplanted SMGs obtained from epiphora patients, while other TJs were unchanged. The intensity of ZO-1 and occludin at the apicolateral membranes as well as occludin in the cytoplasm were increased in epiphora SMGs, but the interaction between ZO-1 and occludin was decreased as evidenced by both co-immunoprecipitation assay and co-immunofluorescence staining. Mechanically, the expression of casein kinase 2α (CK2α) and CK2ß, which was reported to affect occludin modification and the interaction of occludin with ZO-1 in previous literatures, were increased in epiphora glands. Moreover, activation of muscarinic acetylcholine receptor (mAChR) by carbachol directly decreased the interaction between ZO-1 and occludin and increased the acinar TJ width in the freshly isolated human SMGs, whereas these effects were abolished by pretreatment with CK2 inhibitor. Taken together, our findings suggest that decreased interaction between ZO-1 and occludin might contribute to the epiphora occurred in the transplanted SMGs, and mAChR together with the intracellular molecule CK2 might be responsible for the alteration of TJs in epiphora glands.

Synergistic strengthening effect of nanocrystalline copper reinforced with carbon nanotubes.

In this study, a novel multi-walled carbon nanotubes reinforced nanocrystalline copper matrix composite with super high strength and moderate plasticity was synthesized. We successfully overcome the agglomeration problem of the carbon nanotubes and the grain growth problem of the nanocrystalline copper matrix by combined use of the electroless deposition and spark plasma sintering methods. The yield strength of the composite reach up to 692 MPa, which is increased by 2 and 5 times comparing with those of the nanocrystalline and coarse copper, respectively. Simultaneously, the plasticity of the composite was also significantly increased in contrast with that of the nanocrystalline copper. The increase of the density of the carbon nanotubes after coating, the isolation effect caused by the copper coating, and the improvement of the compatibility between the reinforcements and matrix as well as the effective control of the grain growth of the copper matrix all contribute to improving the mechanical properties of the composite. In addition, a new strengthening mechanism, i.e., the series-connection effect of the nanocrystalline copper grains introduced by carbon nanotubes, is proposed to further explain the mechanical behavior of the nanocomposite.

[Development of human embryonic stem cell platforms for human health-safety evaluation].

The human embryonic stem cells (hESCs) serve as a self-renewable, genetically-healthy, pluripotent and single source of all body cells, tissues and organs. Therefore, it is considered as the good standard for all human stem cells by US, Europe and international authorities. In this study, the standard and healthy human mesenchymal progenitors, ligament tissues, cardiomyocytes, keratinocytes, primary neurons, fibroblasts, and salivary serous cells were differentiated from hESCs. The human cellular health-safety of NaF, retinoic acid, 5-fluorouracil, dexamethasone, penicillin G, adriamycin, lead acetate PbAc, bisphenol A-biglycidyl methacrylate (Bis-GMA) were evaluated selectively on the standardized platforms of hESCs, hESCs-derived cardiomyocytes, keratinocytes, primary neurons, and fibroblasts. The evaluations were compared with those on the currently most adopted cellular platforms. Particularly, the sensitivity difference of PM2.5 toxicity on standardized and healthy hESCs derived fibroblasts, currently adopted immortalized human bronchial epithelial cells Beas-2B and human umbilical vein endothelial cells (HUVECs) were evaluated. The RESULTS showed that the standardized hESCs cellular platforms provided more sensitivity and accuracy for human cellular health-safety evaluation.

Thioredoxin 1 mediates TGF-ß-induced epithelial-mesenchymal transition in salivary adenoid cystic carcinoma.

Epithelial-mesenchymal transition (EMT) plays an important role in the invasion and metastasis of salivary adenoid cystic carcinoma (SACC) which is characterized by wide local infiltration, perineural spread, a propensity to local recurrence and late distant metastasis. Our recent studies have disclosed that TGF-ß is a crucial factor for EMT in metastatic SACC. In this study, we further uncovered small redox protein thioredoxin 1 (TXN) as a critical mediator of TGF-ß induced EMT. Immunohistochemistry analysis revealed significantly higher expressions of TXN, thioredoxin reductase 1 (TXNRD1) and N-cadherin, and lower expression of E-cadherin in human metastatic SACC compared to non-metastatic SACC tissues. Consistently, cultured SACC cells with stable TXN overexpression had decreased E-cadherin and increased N-cadherin as well as Snail and Slug expressions. The enhanced migration and invasion potential of these cells was abrogated by Akt or TXNRD1 inhibitors. Expression of N-cadherin and Akt p-Akt decreased, whereas E-cadherin expression increased in a BBSKE (TXNRD1 inhibitor)-dose-dependent manner. In a xenograft mouse model, TXN overexpression facilitated the metastatic potential of SACC-83 cells to the lung. Our results indicate that TXN plays a key role in SACC invasion and metastasis through the modulation of TGF-ß-Akt/GSK-3ß on EMT. TXN could be a potential therapeutic target for SACC.

Survival analysis of oral squamous cell carcinoma in a subgroup of young patients.

Oral squamous cell carcinoma (OSCC) is predominantly a disease of middle-aged men with long-term exposure to tobacco and alcohol. An increasing trend has been reported at a younger age worldwide. Clinical records of 100 patients under the age of 45 years treated specifically for oral cavity SCC in our hospital during a 10-year period were retrospectively analyzed to calculate the survival rates. An obvious male predominance coincided with smoking trend among Chinese young individuals and female patients were more likely to have no traditional risk factors such as smoking or drinking. The 5-year overall survival rate and disease-free survival rate were 61.0% and 75.5%, respectively, consistent with other published series over the decade showing a relatively better survival among the young. No significant differences clearly correlated with outcome when comparing non-smokers non-drinkers to ever-smokers and ever drinkers (P>0.05). Overall survival rate and disease free survival rate was found to be significantly higher in patients with early-stage disease than with advanced stage disease (P=0.001, P=0.009 respectively). The strong influence of clinical stage on prognosis emphasizes the importance of early diagnosis and treatment of oral malignancies for this unique clinical subgroup.