[Effect of aspirin on breast cancer stem cells and stemness of breast cancer]

Objective: To explore the effect of aspirin on the stemness of breast cancer cells and apoptosis induction of breast cancer stem cells. Methods: The 4T1 cells cultured with stem cell culture medium were screened, and immunofluorescence technique, flow cytometry and tumor-forming experiment in vivo were applied to test stem cell characteristics of the tumor spheres. After dealt with aspirin, the apoptosis rate of 4T1 stem cells was analyzed by flow cytometry. The 4T1 cells were cultured in vitro and treated with aspirin, then flow cytometry analysis was used to detect the expression of aldehydedehy drogenase1 (ALDH1), and the expression of stemness genes was tested by Western blot . Then, after culturing the cells with medium containing basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), B27 and N2, the ability of sphere-forming was observed and recorded by microscopy. In vivo BALB/c mice inoculated with 4T1 stem cells were randomly divided into the control group, 10 mg/kg, 30 mg/kg and 100 mg/kg aspirin groups. After 10 days, the mice were dealt with aspirin or NS for 15 days, then the tumor growth was observed and recorded. Results: The ratio of ALDH1 positive cells was up to 78.55%, and 4T1 tumor sphere had a postive expression of ALDH1 and sex determining region Y-box 2 (SOX2). In vivo tumorigenesis abilities of tumor sphere with 1×10(2) 4T1 stem cells could be 75%, while the ratio of normal cells was zero. The ratio of Aspirin-induced apoptosis of 4T1 stem cells at early stage and and late stage increased from 0.36% to 21.61%, and from 4.21% to 21.38%, respectively. Flow cytometry and Western blot assay results indicated that aspirin could reduce the expression of ALDH1, SOX2, octamer-binding transcription factor 4 (OCT4) and NANOG in 4T1 cells. Sphere-forming experiments results showed that aspirin could inhibit sphere forming ability of breast cancer cells. In vivo, aspirin inhibited the growth of tumors with a dose-dependent manner. Conclusion: Aspirin could induce apoptosis of cancer stem cells and reduce stemness of breast cancer, and thus play a growth-inhibiting action on breast cancer.

Towards Understanding the Origin of Cosmic-Ray Positrons

Precision measurements of cosmic ray positrons are presented up to 1 TeV based on 1.9 million positrons collected by the Alpha Magnetic Spectrometer on the International Space Station. The positron flux exhibits complex energy dependence. Its distinctive properties are (a) a significant excess starting from 25.2±1.8  GeV compared to the lower-energy, power-law trend, (b) a sharp dropoff above 284_{-64}^{+91}  GeV, (c) in the entire energy range the positron flux is well described by the sum of a term associated with the positrons produced in the collision of cosmic rays, which dominates at low energies, and a new source term of positrons, which dominates at high energies, and (d) a finite energy cutoff of the source term of E_{s}=810_{-180}^{+310}  GeV is established with a significance of more than 4σ. These experimental data on cosmic ray positrons show that, at high energies, they predominantly originate either from dark matter annihilation or from other astrophysical sources.

Construction, identification, and immunogenic assessments of an HSV-1 mutant vaccine with a UL18 deletion

HSV-1 is a mucosal and nerve pathogen, whose morbidity shows an increasing tendency. Although several antiviral drugs exist, there is no cure for viral latency for virtually all carriers. There is an urgent need for an HSV-1 vaccine to control infection and limit its spread and recurrence. The UL18 gene, encoding a vital component of capsids, is one of the essential genes of HSV-1. Deletion of UL18 from HSV-1 may be exploited as a new approach to develop an attenuated vaccine. The purpose of this study was to construct a DNA vaccine with a full-length UL18 gene deletion of the HSV-1 genome that can induce an effective immune response. A UL18-knockdown plasmid (BAC-HSV-1ΔUL18) was constructed using the bacterial markerless gene knockout system, consisting of the functional pREDI plasmid and BAC-HSV-1 plasmid. Mice were immunized weekly for 3 weeks, and at 1 week post immunization, blood and splenocyte samples of vaccinated and control groups of mice were prepared for immunogenicity assessment. The level of immune response was evaluated using a DTH assay, cytokine determination, and splenocyte proliferation assay. Combination of the pREDI plasmid and BAC-HSV-1 plasmid provides an effective bacterial markerless gene knockout system. Using two-step homologous recombination with the UL18 homologous recombination fragment constructed by multistep PCR amplification, BAC-HSV-1ΔUL18 plasmid vaccine was successfully constructed and was found to significantly enhance cellular immune responses.

A novel FGFR1-binding peptide attenuates the degeneration of articular cartilage in adult mice

OBJECTIVE

We previously reported that genetic ablation of (Fibroblast Growth Factors Receptors) FGFR1 in knee cartilage attenuates the degeneration of articular cartilage in adult mice, which suggests that FGFR1 is a potential targeting molecule for osteoarthritis (OA). Here, we identified R1-P1, an inhibitory peptide for FGFR1 and investigated its effect on the pathogenesis of OA in mice induced by destabilization of medial meniscus (DMM).

DESIGN

Binding ability between R1-P1 and FGFR1 protein was evaluated by enzyme-linked immuno sorbent assay (ELISA) and molecular docking. Alterations in cartilage were evaluated histologically. The expression levels of molecules associated with articular cartilage homeostasis and FGFR1 signaling were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR), Western blotting and immunohistochemistry (IHC). The chondrocyte apoptosis was detected by terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) assay.

RESULTS

R1-P1 had highly binding affinities to human FGFR1 protein, and efficiently inhibited extracellular signal-regulated kinase (ERK)1/2 pathway in mouse primary chondrocytes. In addition, R1-P1 attenuated the IL-1β induced significant loss of proteoglycan in full-thickness cartilage tissue from human femur head. Moreover, this peptide can significantly restore the IL-1β mediated loss of proteoglycan and type II collagen (Col II) and attenuate the expression of matrix metalloproteinase-13 (MMP13) in mouse primary chondrocytes. Finally, intra-articular injection of R1-P1 remarkably attenuated the loss of proteoglycan and the destruction of articular cartilage and decreased the expressions of extracellular matrix (ECM) degrading enzymes and apoptosis in articular chondrocytes of mice underwent DMM surgery.

CONCLUSIONS

R1-P1, a novel inhibitory peptide for FGFR1, attenuates the degeneration of articular cartilage in adult mice, which is a potential leading molecule for the treatment of OA.

TMEM45B is a novel predictive biomarker for prostate cancer progression and metastasis

It is urgently needed to explore the clinical relevance of TMEM45B expression and Prostate cancer(PCa), and determine the predictive significance of TMEM45B as a biomarker for PCa patients.Patient-derived xenograft (PDX) model of PCa with different metastatic potential (LTL-418, LTL-313B, LTL-313H and LTL-331) were developed. The gene expression microarray of LTL-313H and LTL-313B, which derived from a single PCa patient, was performed to identify the candidate biomarker gene, TMRM45B. MSKCC and TCGA PCa patient cohorts were introduced to analyzed the clinical significance of TMEM45B expression. Quantitative Real-Time PCR (qRT-PCR) revealed that there was a significant increase of TMEM45B expression in high metastatic potential tumor lines LTL-313H and LTL-331 compared with the other two low metastatic potential tumor lines(LTL-418, LTL-313B). In MSKCC PCa cohort, the mRNA level of TMEM45B in patients with metastasis was significantly higher than that in primary PCa (P=0.001) and begin prostate hyperplasia (BPH) patients (P<0.001). In addition, the increased TMEM45B expression was positively related with a higher possibility of biochemical recurrence (P=0.016), distant metastasis occurrence(P<0.001) and overall patient survival (P=0.07). Moreover, TMEM45B expression was considered as an independent risk factor for metastasis of PCa based on multivariate logistic regression. Kaplan-Meier analysis showed that patients with elevated TMEM45B had a shorter biochemical recurrence free survival (RFS). For primary PCa patients, subgroup analysis showed that there was a significant association between TMEM45B expression and clinical features in primary PCa cohort. Meanwhile, cases with elevated TMEM45B were more likely to develop metastasis compared to the normal group among N0 primary PCa patients (P=0.010). Primary PCa patient cohort TCGA was used to validate the results, and an obvious relationship was found between TMEM45B and clinical characteristic of PCa (T/N stage, Gleason score, Recurrence / Progress). Furthermore, a significant poor disease free survival (DFS) was investigated in high-level of TMEM45B patients compared with the other remaining cases (P=0.007). Taken together, the increased expression of TMEM45B appears to be significantly associated with prostate carcinoma progression and metastasis which provide a new prognostic biomarker for predicting metastatic potential of PCa patients, especially for primary PCa.

Observation of Complex Time Structures in the Cosmic-Ray Electron and Positron Fluxes with the Alpha Magnetic Spectrometer on the International Space Station

We present high-statistics, precision measurements of the detailed time and energy dependence of the primary cosmic-ray electron flux and positron flux over 79 Bartels rotations from May 2011 to May 2017 in the energy range from 1 to 50 GeV. For the first time, the charge-sign dependent modulation during solar maximum has been investigated in detail by leptons alone. Based on 23.5×10^{6} events, we report the observation of short-term structures on the timescale of months coincident in both the electron flux and the positron flux. These structures are not visible in the e^{+}/e^{-} flux ratio. The precision measurements across the solar polarity reversal show that the ratio exhibits a smooth transition over 830±30 days from one value to another. The midpoint of the transition shows an energy dependent delay relative to the reversal and changes by 260±30 days from 1 to 6 GeV.

Precision Measurement of Cosmic-Ray Nitrogen and its Primary and Secondary Components with the Alpha Magnetic Spectrometer on the International Space Station

A precision measurement of the nitrogen flux with rigidity (momentum per unit charge) from 2.2 GV to 3.3 TV based on 2.2×10^{6} events is presented. The detailed rigidity dependence of the nitrogen flux spectral index is presented for the first time. The spectral index rapidly hardens at high rigidities and becomes identical to the spectral indices of primary He, C, and O cosmic rays above ∼700  GV. We observed that the nitrogen flux Φ_{N} can be presented as the sum of its primary component Φ_{N}^{P} and secondary component Φ_{N}^{S}, Φ_{N}=Φ_{N}^{P}+Φ_{N}^{S}, and we found Φ_{N} is well described by the weighted sum of the oxygen flux Φ_{O} (primary cosmic rays) and the boron flux Φ_{B} (secondary cosmic rays), with Φ_{N}^{P}=(0.090±0.002)×Φ_{O} and Φ_{N}^{S}=(0.62±0.02)×Φ_{B} over the entire rigidity range. This corresponds to a change of the contribution of the secondary cosmic ray component in the nitrogen flux from 70% at a few GV to <30% above 1 TV.

Observation of Fine Time Structures in the Cosmic Proton and Helium Fluxes with the Alpha Magnetic Spectrometer on the International Space Station

We present the precision measurement from May 2011 to May 2017 (79 Bartels rotations) of the proton fluxes at rigidities from 1 to 60 GV and the helium fluxes from 1.9 to 60 GV based on a total of 1×10^{9} events collected with the Alpha Magnetic Spectrometer aboard the International Space Station. This measurement is in solar cycle 24, which has the solar maximum in April 2014. We observed that, below 40 GV, the proton flux and the helium flux show nearly identical fine structures in both time and relative amplitude. The amplitudes of the flux structures decrease with increasing rigidity and vanish above 40 GV. The amplitudes of the structures are reduced during the time period, which started one year after solar maximum, when the proton and helium fluxes steadily increase. Above ∼3  GV the p/He flux ratio is time independent. We observed that below ∼3  GV the ratio has a long-term decrease coinciding with the period during which the fluxes start to rise.

Ultrafast consolidation of bulk nanocrystalline titanium alloy through ultrasonic vibration

Nanocrystalline (NC) materials have fascinating physical and chemical properties, thereby they exhibit great prospects in academic and industrial fields. Highly efficient approaches for fabricating bulk NC materials have been pursued extensively over past decades. However, the instability of nanograin, which is sensitive to processing parameters (such as temperature and time), is always a challenging issue to be solved and remains to date. Herein, we report an ultrafast nanostructuring strategy, namely ultrasonic vibration consolidation (UVC). The strategy utilizes internal friction heat, generated from mutually rubbing between Ti-based metallic glass powders, to heat the glassy alloy rapidly through its supercooled liquid regime, and accelerated viscous flow bonds the powders together. Consequently, bulk NC-Ti alloy with grain size ranging from 10 to 70 nm and nearly full density is consolidated in 2 seconds. The novel consolidation approach proposed here offers a general and highly efficient pathway for manufacturing bulk nanomaterials.

Observation of New Properties of Secondary Cosmic Rays Lithium, Beryllium, and Boron by the Alpha Magnetic Spectrometer on the International Space Station

We report on the observation of new properties of secondary cosmic rays Li, Be, and B measured in the rigidity (momentum per unit charge) range 1.9 GV to 3.3 TV with a total of 5.4×10^{6} nuclei collected by AMS during the first five years of operation aboard the International Space Station. The Li and B fluxes have an identical rigidity dependence above 7 GV and all three fluxes have an identical rigidity dependence above 30 GV with the Li/Be flux ratio of 2.0±0.1. The three fluxes deviate from a single power law above 200 GV in an identical way. This behavior of secondary cosmic rays has also been observed in the AMS measurement of primary cosmic rays He, C, and O but the rigidity dependences of primary cosmic rays and of secondary cosmic rays are distinctly different. In particular, above 200 GV, the secondary cosmic rays harden more than the primary cosmic rays.

Observation of the Identical Rigidity Dependence of He, C, and O Cosmic Rays at High Rigidities by the Alpha Magnetic Spectrometer on the International Space Station

We report the observation of new properties of primary cosmic rays He, C, and O measured in the rigidity (momentum/charge) range 2 GV to 3 TV with 90×10^{6} helium, 8.4×10^{6} carbon, and 7.0×10^{6} oxygen nuclei collected by the Alpha Magnetic Spectrometer (AMS) during the first five years of operation. Above 60 GV, these three spectra have identical rigidity dependence. They all deviate from a single power law above 200 GV and harden in an identical way.

Clinical significance of SCCRO (DCUN1D1) in prostate cancer and its proliferation-inhibiting effect on Lncap cells

OBJECTIVE

  SCCRO/DCUN1D1/DCN1 (squamous cell carcinoma-related oncogene/defective in cullin neddylation 1 domain containing 1/defective in cullin neddylation) is considered as an oncogene, but its role in the prostate cancer (PC) is still not clear. The current study aims to investigate the expression of SCCRO in PC tumor tissues, further its clinical significance, and proliferation inhibiting effect on PC cells in vitro.

PATIENTS AND METHODS

RT-PCR was used to detect the expression of SCCRO in PC tissue and corresponding adjacent normal tissues from 160 cases, and its relationship with clinical pathological characteristics was analyzed. Small interfering RNA (siRNA) expression plasmid targeting SCCRO gene was constructed and transferred into PC cell line Lncap. The effect on proliferation was observed by CCK8 assay, and its influence on invasion and migration of Lncap cells was studied by Transwell Matrigel assay after SCCRO gene was silenced. The expression of focal adhesion kinase (FAK) and matrix metalloproteinase-2 (MMP-2) influenced by SCCRO silencing were detected by Western blot.

RESULTS

mRNA expression of SCCRO protein increased significantly in cancer tissues compared to adjacent normal tissue, especially for T3+T4, N+, and III+IV patients (p<0.05). SCCRO expression was an independent prognostic factor (p<0.05). After SCCRO gene was knocked down by siRNA, the SCCRO protein level decreased 78.4% in the siRNA-3 group. By CCK8 assay, knocking down SCCRO in Lncap significantly reduced the cell proliferation, as well as its migration and invasion capability compared to siRNA-control group (p<0.01) by transwell invasion and migration assay. The expression of FAK and MMP-2 also reduced in siRNA-3 group compared to siRNA control group (p<0.01).

CONCLUSIONS

SCCRO is associated with progression and prognosis of PC. After SCCRO gene was transferred, the growth of Lncap cells was inhibited, and ability of invasion and migration decreased by reducing the expression of FAK and MMP-2. SCCRO has potential to become a new target for the treatment of PC.

Killing two birds with one stone: dual blockade of integrin and FGF signaling through targeting syndecan-4 in postoperative capsular opacification

The most common complication after cataract surgery is postoperative capsular opacification, which includes anterior capsular opacification (ACO) and posterior capsular opacification (PCO). Increased adhesion of lens epithelial cells (LECs) to the intraocular lens material surface promotes ACO formation, whereas proliferation and migration of LECs to the posterior capsule lead to the development of PCO. Cell adhesion is mainly mediated by the binding of integrin to extracellular matrix proteins, while cell proliferation and migration are regulated by fibroblast growth factor (FGF). Syndecan-4 (SDC-4) is a co-receptor for both integrin and FGF signaling pathways. Therefore, SDC-4 may be an ideal therapeutic target for the prevention and treatment of postoperative capsular opacification. However, how SDC-4 contributes to FGF-mediated proliferation, migration, and integrin-mediated adhesion of LECs is unclear. Here, we found that downregulation of SDC-4 inhibited FGF signaling through the blockade of ERK1/2 and PI3K/Akt/mTOR activation, thus suppressing cell proliferation and migration. In addition, downregulation of SDC-4 suppressed integrin-mediated cell adhesion through inhibiting focal adhesion kinase (FAK) phosphorylation. Moreover, SDC-4 knockout mice exhibited normal lens morphology, but had significantly reduced capsular opacification after injury. Finally, SDC-4 expression level was increased in the anterior capsule LECs of age-related cataract patients. Taken together, we for the first time characterized the key regulatory role of SDC-4 in FGF and integrin signaling in human LECs, and provided the basis for future pharmacological interventions of capsular opacification.

Likelihood analysis of the minimal AMSB model

We perform a likelihood analysis of the minimal anomaly-mediated supersymmetry-breaking (mAMSB) model using constraints from cosmology and accelerator experiments. We find that either a wino-like or a Higgsino-like neutralino LSP, [Formula: see text], may provide the cold dark matter (DM), both with similar likelihoods. The upper limit on the DM density from Planck and other experiments enforces [Formula: see text] after the inclusion of Sommerfeld enhancement in its annihilations. If most of the cold DM density is provided by the [Formula: see text], the measured value of the Higgs mass favours a limited range of [Formula: see text] (and also for [Formula: see text] if [Formula: see text]) but the scalar mass [Formula: see text] is poorly constrained. In the wino-LSP case, [Formula: see text] is constrained to about [Formula: see text] and [Formula: see text] to [Formula: see text], whereas in the Higgsino-LSP case [Formula: see text] has just a lower limit [Formula: see text] ([Formula: see text]) and [Formula: see text] is constrained to [Formula: see text] in the [Formula: see text] ([Formula: see text]) scenario. In neither case can the anomalous magnetic moment of the muon, [Formula: see text], be improved significantly relative to its Standard Model (SM) value, nor do flavour measurements constrain the model significantly, and there are poor prospects for discovering supersymmetric particles at the LHC, though there are some prospects for direct DM detection. On the other hand, if the [Formula: see text] contributes only a fraction of the cold DM density, future LHC [Formula: see text]-based searches for gluinos, squarks and heavier chargino and neutralino states as well as disappearing track searches in the wino-like LSP region will be relevant, and interference effects enable [Formula: see text] to agree with the data better than in the SM in the case of wino-like DM with [Formula: see text].

Expression of Dominant Negative K6W-Ubiquitin in the Lens Epithelium via an Adenoviral Vector Delays Posterior Capsule Opacification in a Rabbit Model

PURPOSE

Ubiquitin is involved in cell proliferation and differentiation, and the objective of this study is to investigate the potential of dominant negative Ubiquitin (Ub) with a lysine to tryptophan mutation at the 6 position (K6W) through an adenoviral expression vector in the prevention of posterior capsule opacification (PCO) in a rabbit PCO model.

METHODS

Recombinant dominant negative K6W-Ub adenovirus (RAd-K6W-Ub) with green fluorescent protein (RAd-K6W-Ub/GFP) and RAd-GFP viruses (control) were generated with QBI-HEK 293A cells. New Zealand rabbits receiving lens phacoemulsification were given an intraoperative anterior chamber injection of the viruses. The images of anterior segment photography taken by a slit lamp biomicroscopy were analyzed by posterior capsule opacification manual software (POCOman) for PCO grading. The intraocular pressure (IOP) was detected with a non-contact tonometer (NCT). The expression of α-smooth muscle actin (α-SMA) was assessed by Western blotting. Cell migration ability in cultured rabbit's lens epithelial cells (LECs) was evaluated by scratch healing assay.

RESULTS

The expression of GFP and Ub in the lens epithelium was markedly upregulated after 48 hours vector injection. Eyes injected with RAd-K6W-Ub showed a significantly lower PCO degree compared with controls. Meanwhile, higher IOP and corneal edema was observed in groups with a higher RAd-K6W-Ub virus dosage. The expression of α-SMA was down-regulated in the RAd-K6W-Ub eyes as compared to controls at the 15th day after injection. Cell migration was inhibited by RAd-K6W-Ub infection.

CONCLUSIONS

RAd-K6W-Ub at an appropriate dosage could inhibit the proliferation of LECs and the formation of PCO in rabbit models. However, a higher dosage of Rad- K6W-Ub viral vector caused toxic effects to the surrounding tissues, such as corneal edema and high IOP.