Cancer stem cells (CSCs) are responsible for tumor initiation and progression. Toll-like receptors (TLRs) are highly expressed in cancer cells and associated with poor prognosis. However, a linkage between CSCs and TLRs is unclear, and potential intervention strategies to prevent TLR stimulation-induced CSC formation and underlying mechanisms are lacking. Here, we demonstrate that stimulation of toll-like receptor 3 (TLR3) promotes breast cancer cells toward a CSC phenotype in vitro and in vivo. Importantly, conventional NF-κB signaling pathway is not exclusively responsible for TLR3 activation-enriched CSCs. Intriguingly, simultaneous activation of both β-catenin and NF-κB signaling pathways, but neither alone, is required for the enhanced CSC phenotypes. We have further identified a small molecule cardamonin that can concurrently inhibit β-catenin and NF-κB signals. Cardamonin is capable of effectively abolishing TLR3 activation-enhanced CSC phenotypes in vitro and successfully controlling TLR3 stimulation-induced tumor growth in human breast cancer xenografts. These findings may provide a foundation for developing new strategies to prevent the induction of CSCs during cancer therapies.
Tenckhoff catheter; fracture
The glycoprotein (GP)Ib-IX complex is critical to hemostasis and thrombosis. Its proper assembly is closely correlated with its surface expression level and requires cooperative interactions among extracellular and transmembrane domains of Ibα, Ibβ and IX subunits. Two interfaces have been previously identified between the extracellular domains of Ibβ and IX.
To understand how extracellular domains interact in GPIb-IX.
The Ibβ extracellular domain (IbβE) or the IX counterpart (IXE) in GPIb-IX was replaced with a well-folded IbβE/IXE chimera called IbβEabc, and the effect of domain replacement on assembly and expression of the receptor complex in transiently transfected Chinese hamster ovary cells was analyzed.
Replacing IXE with IbβEabc in GPIb-IX retained interface 1 but not interface 2 between the extracellular domains. While this domain replacement preserved complex integrity, the expression levels of Ibβ and Ibα were significantly reduced. Additional domain replacement with IbβEabc or IbβE in GPIb-IX produced the complex at disparate expression levels that cannot be simply explained by two separate interfaces. In particular, when IbβE in GPIb-IX was replaced by IbβEabc, Ibα and IX were expressed at approximately 70% of the wild-type level. Their levels were not reduced when IXE was changed further to IbβE.
Our results demonstrate the importance of the association between Ibβ and IX extracellular domains for complex assembly and efficient expression, and provide evidence for the structural malleability of these domains that may accommodate and propagate conformational changes therein.
Bernard-Soulier syndrome; leucine-rich repeat proteins; platelet glycoprotein GPIb-IX complex; protein-protein interaction domains; von Willebrand factor receptors
Maize is a well-known host for Meloidogyne incognita, and there is substantial variation in host status among maize genotypes. In previous work it was observed that nematode reproduction increased in the moderately susceptible maize inbred line B73 when the ZmLOX3 gene from oxylipid metabolism was knocked out. Additionally, in this mutant line, use of a nonspecific primer for phenyl alanine ammonialyase (PAL) genes indicated that expression of these genes was reduced in the mutant maize plants whereas expression of several other defense related genes was increased. In this study, we used more specific gene primers to examine the expression of six PAL genes in three maize genotypes that were good, moderate, and poor hosts for M. incognita, respectively. Of the six PAL genes interrogated, two (ZmPAL3 and ZmPAL6) were not expressed in either M. incognita–infected or noninfected roots. Three genes (ZmPAL1, ZmPAL2, and ZmPAL5) were strongly expressed in all three maize lines, in both nematode-infected and noninfected roots, between 2 and 16 d after inoculation (DAI). In contrast, ZmPAL4 was most strongly expressed in the most-resistant maize line W438, was not detected in the most-susceptible maize line CML, and was detected only at 8 DAI in the maize line B73 that supported intermediate levels of reproduction by M. incognita. These observations are consistent with at least one PAL gene playing a role in modulating host status of maize toward M. incognita and suggest a need for additional research to further elucidate this association.
genetics; host susceptibility; maize; Meloidogyne incognita; phenylalanine ammonia lyase; root-knot nematode; Zea mays
Transient ischemia is a leading cause of cognitive dysfunction. Postischemic ROS generation and an increase in the cytosolic Zn2+ level ([Zn2+]c) are critical in delayed CA1 pyramidal neuronal death, but the underlying mechanisms are not fully understood. Here we investigated the role of ROS-sensitive TRPM2 (transient receptor potential melastatin-related 2) channel. Using in vivo and in vitro models of ischemia–reperfusion, we showed that genetic knockout of TRPM2 strongly prohibited the delayed increase in the [Zn2+]c, ROS generation, CA1 pyramidal neuronal death and postischemic memory impairment. Time-lapse imaging revealed that TRPM2 deficiency had no effect on the ischemia-induced increase in the [Zn2+]c but abolished the cytosolic Zn2+ accumulation during reperfusion as well as ROS-elicited increases in the [Zn2+]c. These results provide the first evidence to show a critical role for TRPM2 channel activation during reperfusion in the delayed increase in the [Zn2+]c and CA1 pyramidal neuronal death and identify TRPM2 as a key molecule signaling ROS generation to postischemic brain injury.
Recently, A2B3 type strong spin orbital coupling compounds such as Bi2Te3, Bi2Se3 and Sb2Te3 were theoretically predicated to be topological insulators and demonstrated through experimental efforts. The counterpart compound Sb2Se3 on the other hand was found to be topological trivial, but further theoretical studies indicated that the pressure might induce Sb2Se3 into a topological nontrivial state. Here, we report on the discovery of superconductivity in Sb2Se3 single crystal induced via pressure. Our experiments indicated that Sb2Se3 became superconductive at high pressures above 10 GPa proceeded by a pressure induced insulator to metal like transition at ~3 GPa which should be related to the topological quantum transition. The superconducting transition temperature (TC) increased to around 8.0 K with pressure up to 40 GPa while it keeps ambient structure. High pressure Raman revealed that new modes appeared around 10 GPa and 20 GPa, respectively, which correspond to occurrence of superconductivity and to the change of TC slop as the function of high pressure in conjunction with the evolutions of structural parameters at high pressures.
People who suffer from traumatic brain injury (TBI) often experience cognitive
deficits in spatial reference and working memory. The possible roles of
cyclooxygenase-1 (COX-1) in learning and memory impairment in mice with TBI are far
from well known. Adult mice subjected to TBI were treated with the COX-1 selective
inhibitor SC560. Performance in the open field and on the beam walk was then used to
assess motor and behavioral function 1, 3, 7, 14, and 21 days following injury.
Acquisition of spatial learning and memory retention was assessed using the Morris
water maze on day 15 post-TBI. The expressions of COX-1, prostaglandin E2 (PGE2),
interleukin (IL)-6, brain-derived neurotrophic factor (BDNF), platelet-derived growth
factor BB (PDGF-BB), synapsin-I, and synaptophysin were detected in TBI mice.
Administration of SC560 improved performance of beam walk tasks as well as spatial
learning and memory after TBI. SC560 also reduced expressions of inflammatory markers
IL-6 and PGE2, and reversed the expressions of COX-1, BDNF, PDGF-BB, synapsin-I, and
synaptophysin in TBI mice. The present findings demonstrated that COX-1 might play an
important role in cognitive deficits after TBI and that selective COX-1 inhibition
should be further investigated as a potential therapeutic approach for TBI.
Traumatic brain injury; COX-1; Learning and memory; SC560
The periodontal ligament contains progenitor cells; however, their identity and differentiation potential in vivo remain poorly characterized. Previous results have suggested that periodontal tissue progenitors reside in perivascular areas. Therefore, we utilized a lineage-tracing approach to identify and track periodontal progenitor cells from the perivascular region in vivo. We used an alpha-smooth muscle actin (αSMA) promoter-driven and tamoxifen-inducible Cre system (αSMACreERT2) that, in combination with a reporter mouse line (Ai9), permanently labels a cell population, termed ‘SMA9’. To trace the differentiation of SMA9-labeled cells into osteoblasts/cementoblasts, we utilized a Col2.3GFP transgene, while expression of Scleraxis-GFP was used to follow differentiation into periodontal ligament fibroblasts during normal tissue formation and remodeling following injury. In uninjured three-week-old SMA9 mice, tamoxifen labeled a small population of cells in the periodontal ligament that expanded over time, particularly in the apical region of the root. By 17 days and 7 weeks after labeling, some SMA9-labeled cells expressed markers indicating differentiation into mature lineages, including cementocytes. Following injury, SMA9 cells expanded, and differentiated into cementoblasts, osteoblasts, and periodontal ligament fibroblasts. SMA9-labeled cells represent a source of progenitors that can give rise to mature osteoblasts, cementoblasts, and fibroblasts within the periodontium.
periodontal ligament; cementoblasts; GFP; α-smooth muscle actin; scleraxis; Cre recombinase
Here we show that transgenic expression of miR-17 extends lifespan and inhibits cellular senescence. We propose that miR-17 acts as a critical regulator of cellular senescence and tumorigenesis. We demonstrate that miR-17 targets both ADCY5 and IRS1, upregulating the downstream signals MKP7, FoxO3, LC3B, and HIF1α, and downregulating mTOR, c-myc, cyclin D1, and JNK. Silencing either ADCY5 or IRS1 promoted autophagy and repressed cellular senescence and apoptosis. Repression of ADCY5 by miR-17 translocated membrane-bound RGS2 into the nucleus, promoting interactions of RGS2 with HIF1α and the MKP7 promoter, enhancing MKP7 transcription. ADCY5 repression by miR-17 also facilitated the translocation of EGFR and MKP7 from membrane into cytoplasmic and mitochondrial fractions. Importantly, we found that MKP7 inhibited senescence by dephosphorylating PRAS40 at Thr246 and mTOR at Ser2248, facilitating the interaction and loss of function of both molecules. Thus, the oncogenic miR-17 also acts pleiotropically to inhibit cellular senescence and extend longevity.
No prospective study has investigated the relationship between type 2 diabetes mellitus (T2DM) and the risk of primary liver cancer (PLC) in mainland China, and little is known about the effect of diabetes duration on PLC risk.
Data from two population-based cohorts (the Shanghai Men's Health Study, SMHS, 2002–2006 and the Shanghai Women's Health Study, SWHS, 1996–2000) were thus used to assess the associations among T2DM, diabetes duration and PLC risk in Chinese population.
During follow-up through 2009, 344 incident PLC cases were identified among 60 183 men and 73 105 women. T2DM is significantly associated with the increased risk of PLC in both men [hazard ratio (HR) = 1.63, 95% confidence interval (CI) 1.06–2.51] and women (HR = 1.64, 95% CI 1.03–2.61). The highest risk of incident liver cancer was observed in the first 5 years after diabetes diagnosis, and decreased substantially with the prolonged diabetes duration (Ptrend < 0.001). No synergistic interaction in the development of PLC was found between diabetes and other known risk factors.
T2DM is associated with the increased risk of subsequent liver cancer within 5 years after diagnosis in Chinese population, suggesting that hyperinsulinaemia rather than hyperglycaemia is more likely to be a primary mediator for this association.
China; cohort study; primary liver cancer; type 2 diabetes
BACKGROUND: Metastatic colorectal carcinoma (CRC) tumors with KRAS mutations in exon 2, codons 12 and 13, do not benefit from anti-epidermal growth factor receptor (EGFR) antibody therapy. Current best practice recommends that KRAS mutation analysis be included in patients with CRC as a prerequisite for treatment with cetuximab or panitumumab. We selected 50 CRC formalin fixed paraffin embedded (FFPE) samples to compare a qPCR assay (QIAGEN therascreen® KRAS RGQ PCR Kit) to droplet digital PCR (ddPCR). Wild type and six single nucleotide mutations in KRAS codons 12 and 13 were tested. Methods. DNA was extracted and used in assays employing primers paired with locked nucleic acid (LNA) or TaqMan probes. Droplets were generated and streamed through a droplet reader (BioRad Laboratories, CA). The QuantaSoft software (BioRad Laboratories) was used to analyze the ddPCR data. Results. In limit of detection studies, ddPCR detected 0.002 cpd of known mutant DNA in a background of 1 cpd of wt DNA. Specific KRAS mutations were detected in 16 (of 50) samples using LNA probes. Of the 16 samples tested by LNA probes, 13 were also tested using TaqMan probes, confirming results from the LNA assays. Results from ddPCR assays were compared to results from an outside commercial laboratory. The commercial lab detected and identified mutations in 10 of the 50 FFPE samples tested. ddPCR assays also detected mutations in 10 of these samples. An additional five samples were determined to be positive by commercial qPCR but no specific mutation was reported. ddPCR detected and identified specific mutations in three of these as well as in three samples not identified by commercial qPCR. Conclusions. ddPCR allele specific assays compared well to current commercially available KRAS mutation detection assays. Some cross reactivity was noted in ddPCR assays employing LNA probes but not TaqMan probes.
To examine whether better maternal diet quality was associated with reduced risk for selected birth defects.
A multi-center, population-based case-control study, the National Birth Defects Prevention Study.
Ten participating centers in the United States.
Eligible subjects’ estimated due dates were from October, 1997 through December, 2005. Telephone interviews were conducted with 72% of case and 67% of control mothers. Analyses included 936 cases with neural tube defects (NTDs), 2,475 with orofacial clefts, and 6,147 non-malformed controls.
Food-frequency data were used to calculate the Mediterranean Diet Score (MDS) and Diet Quality Index (DQI), modeled after existing indices.
Main outcome measures
Adjusted odds ratios.
After covariate adjustment, increasing diet quality based on either index was associated with reduced risks for the birth defects studied. The strongest association was between anencephaly and DQI; the odds ratio (OR) for highest versus lowest quartile was 0.49 (95% CI 0.31, 0.75). ORs for cleft lip+/−cleft palate and cleft palate and DQI were also notable, with ORs = 0.66 (0.54, 0.81) and 0.74 (0.56, 0.96), respectively.
Healthier maternal dietary patterns, as measured by diet quality scores, were associated with reduced risks of NTDs and clefts. These results suggest that dietary approaches could lead to further reduction in risks of major birth defects and complement existing efforts to fortify foods and encourage periconceptional multivitamin use.
Corynebacterium; Gordonia sputi; peritonitis
A number of epidemiological studies have reported inconsistent findings on the association between meat consumption and lung cancer.
We therefore conducted a systematic review and meta-analysis to investigate the relationship between meat consumption and lung cancer risk in epidemiological studies.
Twenty-three case–control and 11 cohort studies were included. All studies adjusted for smoking or conducted in never smokers. The summary relative risks (RRs) of lung cancer for the highest versus lowest intake categories were 1.35 (95% confidence interval (CI) 1.08–1.69) for total meat, 1.34 (95% CI 1.18–1.52) for red meat, and 1.06 (95% CI 0.90–1.25) for processed meat. An inverse association was found between poultry intake and lung cancer (RR = 0.91, 95% CI 0.85–0.97), but not for total white meat (RR = 1.06, 95% CI 0.82–1.37) or fish (RR = 1.01, 95% CI 0.96–1.07).
The relationship between meat intake and lung cancer risk appears to depend on the types of meat consumed. A high intake of red meat may increase the risk of lung cancer by about 35%, while a high intake of poultry decreases the risk by about 10%. More well-designed cohort studies on meat mutagens or heme iron, meat cooking preferences, and doneness level are needed to fully characterize this meat–lung cancer association.
case–control study; cohort study; lung cancer; meat consumption; meta-analysis
Sp1 is important for the transcription of many genes. Our previous studies have shown that Sp1 is degraded in normal cell, but it is preserved in cancer cells during mitosis and exists a priori in the daughter cells, ready to engage in gene transcription and thereby contributes to the proliferation and survival of cancer cells. The mechanism by which Sp1 is preserved in cancer cells during mitosis remains unknown. In this study, we observed that Sp1 strongly colocalized with cyclin-dependent kinase 1 (CDK1)/cyclin B1 during mitosis. Moreover, we showed that Sp1 is a novel mitotic substrate of CDK1/cyclin B1 and is phosphorylated by it at Thr 739 before the onset of mitosis. Phospho-Sp1 reduced its DNA-binding ability and facilitated the chromatin condensation process during mitosis. Mutation of Thr739 to alanine resulted in Sp1 remaining in the chromosomes, delayed cell-cycle progression, and eventually led to apoptosis. Screening of Sp1-associated proteins during mitosis by using liquid chromatography/mass spectrometry indicated the tethering of Sp1 to myosin/F-actin. Furthermore, phospho-Sp1 and myosin/F-actin appeared to exist as a congregated ring at the periphery of the chromosome. However, at the end of mitosis and the beginning of interphase, Sp1 was dephosphorylated by PP2A and returned to the chromatin. These results indicate that cancer cells use CDK1 and PP2A to regulate the movement of Sp1 in and out of the chromosomes during cell-cycle progression, which may benefit cancer-cell proliferation.
Sp1; CDK1; PP2A; myosin; mitosis
HeLa cells treated with celastrol, a natural compound with inhibitive effect on proteasome, exhibited increase in apoptotic rate and characteristics of apoptosis. To clarify the signal network activated by celastrol to induce apoptosis, both the direct target proteins and undirect target proteins of celastrol were searched in the present study. Proteasome catalytic subunit β1 was predicted by computational analysis to be a possible direct target of celastrol and confirmed by checking direct effect of celastrol on the activity of recombinant human proteasome subunit β1 in vitro. Undirect target-related proteins of celastrol were searched using proteomic studies including two-dimensional electrophoresis (2-DE) analysis and iTRAQ-based LC-MS analysis. Possible target-related proteins of celastrol such as endoplasmic reticulum protein 29 (ERP29) and mitochondrial import receptor Tom22 (TOM22) were found by 2-DE analysis of total cellular protein expression profiles. Further study showed that celastrol induced ER stress and ER stress inhibitor could ameliorate cell death induced by celastrol. Celastrol induced translocation of Bax into the mitochondria, which might be related to the upregulation of BH-3-only proteins such as BIM and the increase in the expression level of TOM22. To further search possible target-related proteins of celastrol in ER and ER-related fractions, iTRAQ-based LC-MS method was use to analyze protein expression profiles of ER/microsomal vesicles-riched fraction of cells with or without celastrol treatment. Based on possible target-related proteins found in both 2-DE analysis and iTRAQ-based LC-MS analysis, protein–protein interaction (PPI) network was established using bioinformatic analysis. The important role of glycogen synthase kinase-3β (GSK3β) in the signal cascades of celastrol was suggested. Pretreatment of LiCL, an inhibitor of GSK3β, could significantly ameliorate apoptosis induced by celastrol. On the basis of the results of the present study, possible signal network of celastrol activated by celastrol leading to apoptosis was predicted.
celastrol; apoptosis; endothelium reticulum; proteomics; bioinformatics
The objective of this study was to investigate the effect of dietary supplementation with thiazolidinedione (TZD) on growth performance and meat quality of finishing pigs. In Experiment 1, 80 castrated finishing pigs (Large White×Landrace, BW = 54.34 kg) were randomly assigned to 2 treatments with 5 replicates of 8 pigs each. The experimental pigs in the 2 groups were respectively fed with a diet with or without a TZD supplementation (15 mg/kg). In Experiment 2, 80 castrated finishing pigs (Large White×Landrace, BW = 71.46 kg) were divided into 2 treatments as designed in Experiment 1, moreover, carcass evaluations were performed. The results from Experiment 1 showed that TZD supplementation could significantly decreased the average daily feed intake (ADFI) (p<0.05) during 0 to 28 d, without impairing the average daily gain (ADG) (p>0.05). In Experiment 2, the ADG was significantly increased by TZD supplementation during 14 to 28 d and 0 to 28 d (p<0.05) and the feed:gain ratio (F:G) was significantly decreased by TZD supplementation during 0 to 28 d (p<0.05). Compared with the control group, TZD group had significantly higher serum triglyceride (TG) concentration at 28h and serum high-density lipoprotein (HDL) levels at 14 d (p<0.05). Moreover, there was an apparent improvement in the marbling score (p<0.10) and intramuscular fat (IMF) content (p<0.10) of the longissimus dorsi muscle in pigs treated by TZD supplementation. Real-time RT-PCR analyses demonstrated that pigs of TZD group had higher mRNA abundance of PPARγ coactivator 1 (PGC-1) (p<0.05) and fatty acid-binding protein 3 (FABP3) (p<0.05) than pigs of control group. Taken together, these results suggested that dietary TZD supplementation could improve growth performance and increase the IMF content of finishing pigs through regulating the serum parameters and genes mRNA abundance involved in fat metabolism.
Thiazolidinedione; Finishing Pig; Growth Performance; Marbling Score; Intramuscular Fat
Topological superconductivity is one of most fascinating properties of topological quantum matters that was theoretically proposed and can support Majorana Fermions at the edge state. Superconductivity was previously realized in a Cu-intercalated Bi2Se3 topological compound or a Bi2Te3 topological compound at high pressure. Here we report the discovery of superconductivity in the topological compound Sb2Te3 when pressure was applied. The crystal structure analysis results reveal that superconductivity at a low-pressure range occurs at the ambient phase. The Hall coefficient measurements indicate the change of p-type carriers at a low-pressure range within the ambient phase, into n-type at higher pressures, showing intimate relation to superconducting transition temperature. The first principle calculations based on experimental measurements of the crystal lattice show that Sb2Te3 retains its Dirac surface states within the low-pressure ambient phase where superconductivity was observed, which indicates a strong relationship between superconductivity and topology nature.
Achromobacter species; CAPD-related exit-site infection
Turner syndrome; renal failure; dialysis modality