Enterovirus 71 (EV71) is a human enterovirus that has seriously affected the Asia-Pacific area for the past two decades. EV71 infection can result in mild hand-foot-and-mouth disease and herpangina ...and may occasionally lead to severe neurological complications in children. However, the specific biological processes that become altered during EV71 infection remain unclear. To further explore host responses upon EV71 infection, we identified proteins differentially expressed in EV71-infected human glioblastoma SF268 cells using isobaric mass tag (iTRAQ) labeling coupled with multidimensional liquid chromatography–mass spectrometry (LC–MS/MS). Network analysis of proteins altered in cells infected with EV71 revealed that the changed biological processes are related to protein and ion transport, regulation of protein degradation, and homeostatic processes. We confirmed that the levels of NEDD4L and PSMF1 were increased and reduced, respectively, in EV71-infected cells compared to mock-infected control cells. To determine the physiological relevance of our findings, we investigated the consequences of EV71 infection in cells with NEDD4L or PSMF1 depletion. We found that the depletion of NEDD4L significantly reduced the replication of EV71, whereas PSMF1 knockdown enhanced EV71 replication. Collectively, our findings provide the first evidence of proteome-wide dysregulation by EV71 infection and suggest a novel role for the host protein NEDD4L in the replication of this virus.
Abstract Remodeling of atrial extracellular matrix (ECM) in atrial fibrillation (AF) involves changes in the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs). The ...contributions of MMPs and TIMPs to the pathogenesis of AF development have not been clearly defined. This study evaluated the in situ activity and expression of gelatinases (MMP-2 and MMP-9) and their relationship with TIMP-1 or TIMP-3 in atria undergoing rapid atrial pacing for the induction of AF (4 weeks' pacing followed by 2 weeks of maintained AF) in pigs. In AF atria, in situ gelatinase activity was mainly localized in the interstitium of atrial myocardium, and was significantly larger than that of sinus rhythm control (i.e., sham control). The significant increase of MMP-9 in its pro-form and mRNA level, but not MMP-2, was shown to be responsible for the increased gelatinase activity in atria with AF. The inhibitory activities of glycosylated TIMP-1 and TIMP-3, but not TIMP-2, in AF tissues were markedly elevated and also localized in the atrial interstitium. TIMP-1 was found to be mostly colocalized with gelatinase activity over the AF tissues, implying the coexistence of gelatinase activity and TIMP-1, but TIMP-3 appeared only partially colocalized and discontinued the gelatinase activity surrounding the cardiomyocytes. TIMP-1 and TIMP-3 may play differential roles in the inhibition of gelatinase activity in vivo . Together with the survey of several MMPs transcripts and the level of transforming growth factor-β1 (TGF-β1), we proposed that the increased activity of gelatinase (i.e., MMP-9), TIMP-1 and TIMP-3 and their interaction may contribute to atrial ECM remodeling of AF.
Purpose
Highly expressed in cancer protein 1 (Hec1) is an oncogene and a promising molecular target for novel anticancer drugs. The purpose of this study was to evaluate the potential of a Hec1 ...inhibitor, TAI-95, as a treatment for primary liver cancer.
Methods
In vitro and in vivo methods were used to test the activity of TAI-95. Gene expression analysis was used to evaluate clinical correlation of the target.
Results
In vitro growth inhibition results showed that TAI-95 has excellent potency on a wide range of primary liver cancer cell lines (hepatoblastoma or hepatocellular carcinoma) (GI
50
30–70 nM), which was superior to sorafenib and other cytotoxic agents. TAI-95 was relatively inactive in non-cancerous cell lines (GI
50
> 10 μM). TAI-95 disrupts the interaction between Hec1 and Nek2 and leads to degradation of Nek2, chromosomal misalignment, and apoptotic cell death. TAI-95 showed synergistic activity in selected cancer cell lines with doxorubicin, paclitaxel, and topotecan, but not with sorafenib. TAI-95 shows excellent potency in a Huh-7 xenograft mouse model when administered orally. Gene expression analysis of clinical samples demonstrated increased expression of Hec1/NDC80 and associated genes (Nek2, SMC1A, and SMC2) in 27 % of patients, highlighting the potential for using this therapeutic approach to target patients with high Hec1 expression.
Conclusion
Inhibition of Hec1 using small molecule approach may represent a promising novel approach for the treatment of primary liver cancers.
5-Fluorouracil (5-FU) is used to treat various cancers, including non-small-cell lung cancer (NSCLC). It inhibits nucleotide synthesis and induces single- and double-strand DNA breaks. In the ...homologous recombination pathway, radiation-sensitive 52 (Rad52) plays a crucial role in DNA repair by promoting the annealing of complementary single-stranded DNA and stimulating Rad51 recombinase activity. Erlotinib (Tarceva) is a selective epidermal growth factor receptor tyrosine kinase inhibitor with clinical activity against NSCLC cells. However, whether the combination of 5-FU and erlotinib has synergistic activity against NSCLC cells is unknown.
After the 5-FU and/or erlotinib treatment, the expressions of Rad52 mRNA were determined by quantitative real-time polymerase chain reaction analysis. Protein levels of Rad52 and phospho-p38 MAPK were determined by Western blot analysis. We used specific Rad52 or p38 MAPK small interfering RNA and p38 MAPK inhibitor (SB2023580) to examine the role of p38 MAPK-Rad52 signal in regulating the chemosensitivity of 5-FU and/or erlotinib. Cell viability was assessed by MTS assay and trypan blue exclusion assay.
In 2 squamous cell carcinoma cell lines, namely, H520 and H1703, 5-FU reduced Rad52 expression in a p38 MAPK inactivation-dependent manner. Enhancement of p38 MAPK activity by transfection with MKK6E (a constitutively active form of MKK6) vector increased the Rad52 protein level and cell survival by 5-FU. However, in human lung bronchioloalveolar cell adenocarcinoma A549 cells, 5-FU reduced Rad52 expression and induced cytotoxicity independent of p38 MAPK. Moreover, 5-FU synergistically enhanced the cytotoxicity and cell growth inhibition of erlotinib in NSCLC cells; these effects were associated with Rad52 downregulation and p38 MAPK inactivation in H520 and H1703 cells.
The results provide a rationale for combining 5-FU and erlotinib in lung cancer treatment.
Current cytotoxic chemotherapy produces clinical benefit in patients with breast cancer but the survival impact is modest. To explore novel cytotoxic agents for the treatment of advanced disease, we ...have characterized a new and pharmacokinetically improved Hec1-targeted compound, TAI-95. Nine of 11 breast cancer cell lines tested were sensitive to nanomolar levels of TAI-95 (GI(50) = 14.29-73.65 nmol/L), and more importantly, TAI-95 was active on a number of cell lines that were resistant (GI(50) > 10 μmol/L) to other established cytotoxic agents. TAI-95 demonstrates strong inhibition of in vivo tumor growth of breast cancer model when administered orally, without inducing weight loss or other obvious toxicity. Mechanistically, TAI-95 acts by disrupting the interaction between Hec1 and Nek2, leading to apoptotic cell death in breast cancer cells. Furthermore, TAI-95 is active on multidrug-resistant (MDR) cell lines and led to downregulation of the expression of P-glycoprotein (Pgp), an MDR gene. In addition, TAI-95 increased the potency of cytotoxic Pgp substrates, including doxorubicin and topotecan. Certain clinical subtypes of breast cancer more likely to respond to Hec1-targeted therapy were identified and these subtypes are the ones associated with poor prognosis. This study highlights the potential of the novel anticancer compound TAI-95 in difficult-to-treat breast cancers.
We study transport properties of the helical edge states of two-dimensional integer and fractional topological insulators via double constrictions. Such constrictions couple the upper and lower edges ...of the sample and can be made and tuned by adding side gates to the system. Using renormalization group and duality mapping, we analyze phase diagrams and transport properties in each of these cases. Most interesting is the case of two constrictions tuned to resonance, where we obtain Kondo behavior, with a tunable Kondo temperature. Moving away from resonance gives the possibility of a metal-insulator transition at some finite detuning. For integer topological insulators, this physics is predicted to occur for realistic interaction strengths and gives a conductance G with two temperature T scales where the sign of dG/dT changes, one being related to the Kondo temperature while the other is related to the detuning.
Bias polarity‐induced transformation of point contact resistive switching memory from a single transparent conductive metal oxide layer is demonstrated on three kinds of transparent conductive oxide ...(TCO) layers, including indium tin oxide, fluorine‐doped tin oxide, and aluminum‐doped zinc oxide, as conducting electrode and memristive material by the controllably electrical field simultaneously.
Hydrocarbon vents have recently been reported to contribute considerable amounts of dissolved organic carbon (DOC) to the oceans. Many such hydrocarbon vents widely exist in the northern South China ...Sea (NSCS). To investigate if these hydrocarbon vent sites release DOC, we used a real-time video multiple-corer to collect bottom seawater and surface sediments at vent sites. We analyzed concentrations of DOC in these samples and estimated DOC fluxes. Elevated DOC concentrations in the porewaters were found at some sites suggesting that DOC may come from these hydrocarbon vents. Benthic fluxes of DOC from these sediments were 28 to 1264 μmol m(-2 )d(-1) (on average ~321 μmol m(-2 )d(-1)) which are several times higher than most DOC fluxes in coastal and continental margin sediments. The results demonstrate that the real-time video multiple-corer can precisely collect samples at vent sites. The estimated benthic DOC flux from the methane venting sites (8.6 × 10(6 )mol y(-1)), is 24% of the DOC discharge from the Pearl River to the South China Sea, indicating that these sediments make an important contribution to the DOC in deep waters.
In this study, rice-phenolic acid complexes were prepared by processing rice kernels in chlorogenic acid (CGA) solutions of different concentrations, followed by heating at different adsorption ...times. An adsorption treatment of 80 °C for 3 h effectively enhanced the complexation of rice samples with CGA (3.86 mg/g) and imparted antioxidant capacities to the complex. An apparent interaction between CGA and rice starch molecules was suggested by electrospray ionization mass spectrometry analysis. Our results revealed that rice samples were functionalized with CGA by modifying their physicochemical properties by increasing swelling ability (9.1%) and breakdown value (24.7%), and retarding retrogradation (−9.8%). The complexation of rice with a high dose of CGA could significantly reduce in vitro and in vivo starch digestibility by 41.9% and 23.0%, respectively, relative to control. This treatment is considered a potential way to confer rice with an increased resistance to digestion, along with desirable pasting properties.
Abstract Background Lung ischemia-reperfusion (I/R) injury plays an important role in lung transplantation. Less well known is the role of sildenafil in lung I/R injury; therefore, we attempted to ...determine whether sildenafil could alleviate lung apoptosis and tissue injury in a rat model. Methods Forty male Sprague-Dawley rats were randomized into four groups: saline + sham, saline + I/R, sildenafil + sham, and sildenafil + I/R groups. Three hours before the operation, each rat received normal saline or sildenafil (10 mg/kg) by lavage. The animals designed to I/R injury were subjected to 2 h of ischemia induced by occlusion of left pulmonary artery, veins, and bronchus, followed by reperfusion for 2 h. The lung tissue was harvested for the analysis of the expression of Bax, Bcl-2, p53, caspase 3, tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and wet/dry (W/D) weight ratio. Results Compared with the saline + sham group, the saline + I/R group had significant increases in Bax, p53, Bax/Bcl-2 ratio, caspase 3, IL-6, TNF-α, and W/D weight ratio but a decrease in Bcl-2 ( P < 0.05). Compared with the saline + I/R group, sildenafil + I/R group had significant decreases in Bax, p53, Bax/Bcl-2 ratio, caspase 3, IL-6, TNF-α level, and W/D weight ratio but an increase in Bcl-2 expression ( P < 0.05). Compared with the sildenafil + sham group, there were significant increases in p53 and TNF-α expression in the sildenafil + I/R group ( P < 0.05). Conclusions Pretreatment with sildenafil alleviates lung apoptosis and tissue injury in a rat model.
PDF
