ARRY-334543 is a small molecule inhibitor of ErbB1 and ErbB2 tyrosine kinases. We conducted this study to determine whether ARRY-334543 can enhance the efficacy of conventional anticancer drugs through interaction with ABC transporters.
Lung cancer cell line NCI-H460 and its ABCG2-overexpressing NCI-H460/MX20, as well as the ABCG2-, ABCB1-, and ABCC10-overexpressing transfected cell lines were used for the reversal study.
Our results demonstrate that ARRY-334543 (1.0 μM) significantly reversed ABCG2-mediated multidrug resistance (MDR) by directly inhibiting the drug efflux function of ABCG2, resulting in the elevated intracellular accumulation of chemotherapeutic drugs in the ABCG2-overexpressing cell lines. In addition, in isolated membranes, ARRY-334543 stimulated ATPase activity and inhibited photolabeling of ABCG2 with [125I]-iodoarylazidoprazosin in a concentration-dependent manner indicating that this drug directly interacts at the drug-binding pocket of this transporter. ARRY-334543 (1.0 μM) only slightly reversed ABCB1- and partially reversed ABCC10-mediated MDR suggesting that it exhibits high affinity towards ABCG2. Moreover, homology modeling predicted the binding conformation of ARRY-334543 at Arg482 centroid-based grid of ABCG2. However, ARRY-334543 at reversal concentration did not affect the expression level of ABCG2, AKT and ERK1/2 and regulate the re-localization of ABCG2.
We conclude that ARRY-334543 significantly reverses drug resistance mediated by ABCG2.
ARRY-334543; ABCG2; Multidrug resistance; Tyrosine kinase inhibitor; Lung cancer
Mdm2, an E3 ubiquitin ligase, negatively regulates the tumor suppressor p53. In this study, we utilized a conditional Mdm2 allele, Mdm2FM, and a CreER Tamoxifen inducible recombination system to examine the effects of global Mdm2 loss in adult mice. Two different Tamoxifen injection regimens caused 100% lethality of Mdm2FM/−;CreER mice. Both radio-sensitive and radio-insensitive tissues were impaired. Strikingly, a large number of radio-insensitive tissues, including the kidney, liver, heart, retina and hippocampus, exhibited various pathological defects. Similar Tamoxifen injections in older (16–18 month old) Mdm2FM/−;CreER mice showed abnormalities only in the kidney. In addition, transcriptional activation of p21, Puma and multiple senescence markers in young (2–4 month old) mice following loss of Mdm2 was dampened in older mice. All phenotypes were p53-dependent as Mdm2FM/−;p53−/−;CreER mice subjected to the same Tamoxifen regimens were normal. Our findings implicate numerous possible toxicities in many normal tissues upon use of cancer therapies that aim to inhibit Mdm2 in tumors with wild type p53.
Mdm2 inhibition; radio-insensitive tissues; cancer therapy
The diversity of fungi associated with the gut of Pantala flavescens larvae was investigated using a culture-dependent method and molecular identification based on an analysis of the internally transcribed spacer sequence. In total, 48 fungal isolates were obtained from P. flavescens larvae. Based on phylogenetic analyses, the fungal isolates were grouped in 5 classes and 12 different genera. Fourteen bacterial 16S rDNA sequences derived from total genomic DNA extractions of fungal mycelia were obtained. The majority of the sequences were associated with Proteobacteria (13/14), and one Bacillaceae (1/14) was included. Leclercia sp., Oceanobacillus oncorhynchi and Methylobacterium extorquens, were reported for the first time as bacterial endosymbionts in fungi. High-performance liquid chromatography (HPLC) analysis indicated that bacterial symbionts produced specific metabolites and also exerted an inhibitory effect on fungal metabolites. The biological activity of the fungal culture extracts against the pathogenic bacteria Staphylococcus aureus (ATCC 6538), Bacillus subtilis (ATCC 6633) and Escherichia coli (ATCC 8739) was investigated, and 20 extracts (42%) exhibited antibacterial activity against at least one of the tested bacterial strains. This study is the first report on the diversity and antibacterial activity of symbiotic fungi residing in the gut of P. flavescens larvae, and the results show that these fungi are highly diverse and could be exploited as a potential source of bioactive compounds.
The prognostic value of the primary lesion pretreatment apparent diffusion coefficient (ADC), which is obtained by diffusion-weighted magnetic resonance imaging (MR-DWI), remains unknown in nasopharyngeal carcinoma (NPC). Thus, to investigate whether the pretreatment ADC value as measured from the primary site on MR-DWI is an independent prognostic factor in NPC, we retrospectively reviewed a cohort of 541 patients with histologically-proven stage I-IVB NPC. All patients underwent MRI using a 3-Tesla system (Trio Tim; Siemens, Erlangen Germany). To calculate ADC, the primary lesion was designated on the ADC map at the level of the largest tumor diameter to cover most of the lesion, avoiding cystic or necrotic components. Median and mean (±SD) pretreatment ADC were 0.713 and 0.716 ± 0.079 × 10−3 mm2/s, respectively. Univariate and multivariate analysis confirmed high pretreatment ADC was a good prognostic factor for poor local relapse-free survival and disease-free survival. Furthermore, the area under the ROC curve for prediction of local failure significantly increased when pretreatment ADC was combined with T classification (P = 0.004). Thus, pretreatment ADC might provide useful information for predicting outcome and selecting high-risk patients appropriate for more aggressive therapy. Further studies are warranted to investigate the biological basis of this observation.
Acellular corneal stroma matrix has been used for corneal stroma engineering. However, because of its compact tissue structure, regrowth of keratocytes into the scaffold is difficult. Previously, we developed a sandwich model for cartilage engineering using acellular cartilage sheets. In the present study, we tested this model for corneal stroma regeneration using acellular porcine corneal stroma (APCS) sheets and keratocytes. Porcine corneas were decellularized by NaCl treatment, and the APCS was cut into 20-μm-thick sheets. A rabbit corneal stroma defect model was created by lamellar keratoplasty and repaired by transplantation of five pieces of APCS sheets with keratocytes. Six months after transplantation, transparent corneas were present in the experimental group, which were confirmed by anterior segment optical coherence tomography examination and transmittance examination. The biomechanical properties in the experimental group were similar to those of normal cornea. Histological analyses showed an even distribution of keratocytes and well-oriented matrix in the stroma layer in the experimental group. Together, these results demonstrated that the sandwich model using acellular corneal stroma sheets and keratocytes could be potentially useful for corneal stroma regeneration.
of novel hybrids from natural product oridonin and nitrogen mustards
were designed and synthesized to obtain more efficacious and less
toxic antitumor agents. The antiproliferative evaluation showed that
most conjugates were more potent than their parent compounds oridonin
and clinically used nitrogen mustards against four human cancer cell
lines (K562, MCF-7, Bel-7402, and MGC-803). Furthermore, the representative
compounds 16a–c exhibited antiproliferative
activities against the multidrug resistant cell lines (SW620/AD300
and NCI-H460/MX20). It was shown that the most effective compound 16b possesses a strong inhibitory activity with an IC50 value 21-fold lower than that of oridonin in MCF-7 cells
and also exhibits selective cytotoxicity toward the cancer cells.
Intriguingly, compound 16b has been demonstrated to significantly
induce apoptosis and affect cell cycle progression in human hepatoma
Oridonin; antiproliferative activities; nitrogen mustards; combination principle; drug-resistant; apoptosis
AIM: To investigate hepatitis B virus (HBV) prevalence in the general population in China.
METHODS: A total of 148931 individuals were investigated by multistage random sampling in Eastern China. Data were collected on demographics and hepatitis B vaccination history, and serum was tested for hepatitis B surface antigen (HBsAg) by ELISA.
RESULTS: A total of 11469 participants (7.70%, 95%CI: 7.57%-7.84%) were positive for HBsAg. HBsAg prevalence was 0.77% among children < 5 years old but increased progressively from adolescents (1.40%-2.55%) to adults (5.69%-11.22%). A decrease in HBsAg prevalence was strongly associated with vaccination and familial history of HBV among both children and adult groups. Meanwhile, HBsAg risk in adults was associated with invasive testing and sharing needles. The HBV immunization rate among participants aged < 20 years was 93.30% (95%CI: 93.01%-93.58%). Significant difference in HBsAg prevalence appeared between vaccinated and unvaccinated participants (3.59% vs 10.22%).
CONCLUSION: Although the national goal of HBsAg prevalence < 1% among children < 5 years old has been reached, immunization programs should be maintained to prevent resurgence.
Epidemiological study; Familial history; Hepatitis B surface antigen; Immunization; General population
As a common cardiac disease mainly caused by gene mutations in sarcomeric cytoskeletal, calcium-handling, nuclear envelope, desmosomal, and transcription factor genes, inherited cardiomyopathy is becoming one of the major etiological factors of sudden cardiac death (SCD) and heart failure (HF). This disease is characterized by remarkable genetic heterogeneity, which makes it difficult to screen for pathogenic mutations using Sanger sequencing. In the present study, three probands, one with familial hypertrophic cardiomyopathy (FHCM) and two with familial dilated cardiomyopathy (FDCM), were recruited together with their respective family members. Using next-generation sequencing technology (NGS), 24 genes frequently known to be related to inherited cardiomyopathy were screened. Two hot spots (TNNI3-p.Arg145Gly, and LMNA-p.Arg190Trp) and double (LMNA-p.Arg190Trp plus MYH7-p.Arg1045His) heterozygous mutations were found to be highly correlated with familial cardiomyopathy. FDCM patients with doubly heterozygous mutations show a notably severe phenotype as we could confirm in our study; this indicates that the double mutations had a dose effect. In addition, it is proposed that genetic testing using NGS technology can be used as a cost-effective screening tool and help guide the treatment of patients with familial cardiomyopathy particularly regarding the risk of family members who are clinically asymptomatic.
Objectives. The concept now emerging is that higher thyroid-stimulating hormone (TSH) and lower thyroid hormone levels within the euthyroid range may adversely affect atherosclerosis. The present study aimed to investigate the potential associations between thyroid parameters and hyperhomocysteinaemia in a cohort of euthyroid diabetic subjects. Material and Methods. Two hundred and seventy-three euthyroid diabetic subjects (167 males and 106 females) were consecutively recruited in this cross-sectional study. Clinical and biomedical data was collected. Results. TSH level was higher in females than males. Compared to normal-homocysteine group, hyperhomocysteinaemia group was more likely to be elderly, males, with longer diabetes history, and with lower diastolic blood pressure. Free thyroxine (FT4) level was lower in hyperhomocysteinaemia group than in normal-homocysteine group; however, it was not statistically significant. Adjusted for age, sex, body mass index, duration of diabetes, blood pressure, fasting glucose, total cholesterol, and triglyceride in logistic regression analyses, hyperhomocysteinaemia was significantly correlated with FT4 (P = 0.021). No significant association was found with TSH or free triiodothyronine. When analyzed in subjects with TSH < 2.5 uIU/mL separately, we got similar results. Conclusions. In conclusion, we identified a relation between hyperhomocysteinemia and FT4 in a group of euthyroid diabetic patients.
Brain circuits endow behavioral flexibility. Here, we study circuits encoding flexible chemotaxis in C. elegans, where the animal navigates up or down NaCl gradients (positive or negative chemotaxis) to reach the salt concentration of previous growth (the setpoint). The ASER sensory neuron mediates positive and negative chemotaxis by regulating the frequency and direction of reorientation movements in response to salt gradients. Both salt gradients and setpoint memory are encoded in ASER temporal activity patterns. Distinct temporal activity patterns in interneurons immediately downstream of ASER encode chemotactic movement decisions. Different interneuron combinations regulate positive vs. negative chemotaxis. We conclude that sensorimotor pathways are segregated immediately after the primary sensory neuron in the chemotaxis circuit, and sensory representation is rapidly transformed to motor representation at the first interneuron layer. Our study reveals compact encoding of perception, memory, and locomotion in an experience-dependent navigational behavior in C. elegans.
The p53 (TP53) tumor suppressor is the most frequently mutated gene in human cancers. Restoring expression of wild-type p53 has led to tumor growth suppression in a variety of tumor models that are p53 deficient. Other mechanisms, e.g. up-regulation of Mdm2, exist in tumors to inactivate the p53 pathway. Mdm2, an E3 ubiquitin-ligase that targets p53 for proteasomal degradation, is present at high levels in many tumors with wild-type p53. In this study, the effects of restoring p53 activity were probed in Mdm2-overexpressing tumors genetically using animal models. Here it was demonstrated that elevated levels of Mdm2 and decreased levels of p53 act additively to dampen p53 activity in DNA damage response and tumor development. Our data further indicate that restoration of wild-type p53 expression in Mdm2-overexpressing angiosarcomas results in tumor stasis and regression in some cases. Finally, it was determined that restored p53 suppressed cell proliferation but did not elicit apoptosis in the Mdm2-overexpressing angiosarcomas.
p53; Mdm2 overexpression; cancer therapy
MTOR, a central regulator of autophagy, is involved in cancer and cardiovascular and neurological diseases. Modulating the MTOR signaling balance could be of great significance for numerous diseases. No chemical activators of MTOR have been found, and the urgent challenge is to find novel MTOR downstream components. In previous studies, we found a chemical small molecule, 3-benzyl-5-((2-nitrophenoxy) methyl)–dihydrofuran-2(3H)-one (3BDO), that inhibited autophagy in human umbilical vein endothelial cells (HUVECs) and neuronal cells. Here, we found that 3BDO activated MTOR by targeting FKBP1A (FK506-binding protein 1A, 12 kDa). We next used 3BDO to detect novel factors downstream of the MTOR signaling pathway. Activation of MTOR by 3BDO increased the phosphorylation of TIA1 (TIA1 cytotoxic granule-associated RNA binding protein/T-cell-restricted intracellular antigen-1). Finally, we used gene microarray, RNA interference, RNA-ChIP assay, bioinformatics, luciferase reporter assay, and other assays and found that 3BDO greatly decreased the level of a long noncoding RNA (lncRNA) derived from the 3′ untranslated region (3′UTR) of TGFB2, known as FLJ11812. TIA1 was responsible for processing FLJ11812. Further experiments results showed that FLJ11812 could bind with MIR4459 targeting ATG13 (autophagy-related 13), and ATG13 protein level was decreased along with 3BDO-decreased FLJ11812 level. Here, we provide a new activator of MTOR, and our findings highlight the role of the lncRNA in autophagy.
MTOR activator; TIA1; lncRNA; MIR4459; ATG13; autophagy
Six out of the 64 studied Proteus mirabilis isolates from 11 poultry farms in China contained Salmonella genomic island 1 (SGI1). PCR mapping showed that the complete nucleotide sequences of SGI1s ranged from 33.2 to 42.5 kb. Three novel variants, SGI1-W, SGI1-X, and SGI1-Y, have been characterized. Resistance genes lnuF, dfrA25, and qnrB2 were identified in SGI1 for the first time.
Outpatient surgery is increasingly delivered at freestanding ambulatory surgery centers (ASCs), which are thought to deliver quality care at lower costs per episode. The objective of this study was to understand potential facilitators and/or barriers to the introduction of freestanding ASCs in the United States.
This is an observational study conducted from 2008–2010 using a 20% sample of Medicare claims. Potential determinants of ASC dissemination, including population, system, and legal factors, were compared between markets that always had ASCs, never had ASCs, and those that had new ASCs open during the study. Multivariable logistic regression was used to determine characteristics of markets associated with the opening of a new facility in a previously naïve market.
New ASCs opened in 67 previously naïve markets between 2008 and 2010. ASCs were more likely to open in HSAs that were urban (adjusted OR 4.10; 95% CI 1.51–10.96), had higher per capita income (adjusted OR 3.83; 95% CI 1.43–10.45), and had less competition for outpatient surgery (adjusted OR 2.13; 95% CI 1.02–4.45). Legal considerations and latent need, as measured by case volumes of hospital-based outpatient surgery in 2007, were not associated with the opening of a new ASC.
Freestanding ASCs opened in advantageous socioeconomic environments with the least amount of competition. Because of their associated efficiency advantages, policymakers might consider strategies to promote ASC diffusion in disadvantaged markets to potentially improve access and reduce costs.
hospital service area; healthcare market; policy; socioeconomic; regulatory; certificate of need; Herfindahl-Hirschman Index
Geranium wilfordii is one of the major species used as Herba Geranii (lao-guan-cao) in China, it is commonly used solely or in polyherbal formulations for treatment of joint pain resulted from rheumatoid arthritis (RA) and gout. This herb is used to validate a target-based drug screening platform called Herbochip® and evaluate anti-inflammatory effects of Geranium wilfordii ethanolic extract (GWE) using tumor necrosis factor-alpha (TNF-α) as a drug target together with subsequent in vitro and in vivo assays.
A microarray-based drug screening platform was constructed by arraying HPLC fractions of herbal extracts onto a surface-activated polystyrene slide (Herbochip®). Using TNF-α as a molecular probe, fractions of 82 selected herbal extracts, including GWE, were then screened to identify plant extracts containing TNF-α-binding agents. Cytotoxicity of GWE and modulatory effects of GWE on TNF-α expression were evaluated by cell-based assays using TNF-α sensitive murine fibrosarcoma L929 cells as an in vitro model.
The in vivo anti-inflammatory effects of GWE were further assessed by animal models including carrageenan-induced hind paw edema in rats and xylene-induced ear edema in mice, in comparison with aspirin. The hybridization data obtained by Herbochip® analysis showed unambiguous signals which confirmed TNF-α binding activity in 46 herbal extracts including GWE. In L929 cells GWE showed significant inhibitory effect on TNF-α expression with negligible cytotoxicity. GWE also significantly inhibited formation of carrageenan-induced hind paw edema and xylene-induced ear edema in animal models, indicating that it indeed possessed anti-inflammatory activity.
We have thus validated effectiveness of the Herbochip® drug screening platform using TNF-α as a molecular target. Subsequent experiments on GWE lead us to conclude that the anti-RA activity of GWE can be attributed to inhibitory effect of GWE on the key inflammatory factor, TNF-α. Our results contribute towards validation of the traditional use of GWE in the treatment of RA and other inflammatory joint disorders.
Geraniaceae; Geranium wilfordii; Anti-inflammatory; Anti-rheumatoid arthritis; Herbochip; TNF-alpha
Although some features of plaque instability can be observed in genetically modified mouse models, atherothrombosis induction in mice has been attested to be difficult. We sought to test the hypothesis that alterations in blood thrombogenicity might have an essential role in the development of atherothrombosis in ApoE−/− mice. In a mouse model of plaque destabilization established in our laboratory, we targeted blood thrombogenicity by systemically overexpressing murine prothrombin via adenovirus-mediated gene transfer. Systemic overexpression of prothrombin increased blood thrombogenicity, and remarkably, precipitated atherothrombotic events in 70% of the animals. The affected plaques displayed features of culprit lesions as seen in human coronary arteries, including fibrous cap disruption, luminal thrombosis, and plaque hemorrhage. Treatment with aspirin and clopidogrel substantially reduced the incidence of atherothrombosis in this model. Mechanistically, increased inflammation, apoptosis and upregulation of metalloproteinases contributed to the development of plaque destabilization and atherothrombosis. As conclusions, targeting blood thrombogenicity in mice can faithfully reproduce the process of atherothrombosis as occurring in human coronary vessels. Our results suggest that blood-plaque interactions are critical in the development of atherothrombosis in mice, substantiating the argument that changes in blood coagulation status may have a determinant role in the onset of acute coronary syndrome.
Minimal residual disease detection in the bone marrow is usually performed in patients with acute myeloid leukemia undergoing one course of induction chemotherapy. To optimize the chemotherapy strategies, more practical and sensitive markers are needed to monitor the early treatment response during induction. For instance, peripheral blood (PB) blast clearance rate may be considered as such a monitoring marker.
PB blasts were monitored through multiparameter flow cytometry (MFC). Absolute counts were determined before treatment (D0) and at specified time points of induction chemotherapy (D3, D5, D7, and D9). The cut-off value of D5 peripheral blast clearance rate (D5-PBCR) was defined through receiver operating characteristic (ROC) analysis. Prognostic effects were compared among different patient groups according to D5-PBCR cut-off value.
D5-PBCR cut-off value was determined as 99.55%. Prognostic analysis showed that patients with D5-PBCR ≥99.55% more likely achieved complete remission (94.6% vs. 56.1%, P < 0.001) and maintained a relapse-free status than other patients (80.56% vs. 57.14%, P = 0.027). Survival analysis revealed that relapse-free survival (RFS) and overall survival (OS) were longer in patients with D5-PBCR ≥99.55% than in other patients (two-year OS: 71.0% vs. 38.7%, P = 0.011; two-year RFS: 69.4% vs. 30.7%, P = 0.026). In cytogenetic-molecular intermediate-risk group, a subgroup with worse outcome could be distinguished on the basis of D5-PBCR (<99.55%; OS: P = 0.033, RFS: P = 0.086).
An effective evaluation method of early treatment response was established by monitoring PB blasts through MFC. D5-PBCR cut-off value (99.55%) can be a reliable reference to predict treatment response and outcome in early stages of chemotherapy. The proposed marker may be used in induction regimen modification and help optimize cytogenetic-molecular prognostic risk stratification.
Electronic supplementary material
The online version of this article (doi:10.1186/s13045-015-0145-1) contains supplementary material, which is available to authorized users.
Peripheral blast clearance rate; Early treatment response; Prognosis; AML
Scrub typhus, caused by Orientia tsutsugamushi, has emerged recently in Jingjiang City, China where the disease had not been known to exist. We analyzed epidemiological data, clinical characteristics and risk factors of scrub typhus outbreak in Jingjiang City, 2013. The 271 clinically diagnosed patients were predominantly farmers 50 to 69 years old and the peak of onset was early to mid-November. For the 187 laboratory-confirmed cases, the major clinical manifestations of the patients were fever (100%), eschar (88.2%), rash (87.7%), chills (87.7%), and headache (66.8%). A community-based case-control study was carried out to investigate the risk factors of the scrub typhus outbreak. Bundling or moving waste straw (OR=9.0, 95%CI 4.6-17.8) and living at the edge of village (OR=0.6, 95%CI 0.4-0.9) posed the highest risks through single- and multi-variable conditional logistic regression. Phylogenetic analysis of the 56-kDa TSA gene showed that the new cluster (GB-C2) and the previously reported cluster (GB-C1) of O. tsutsugamushi were associated with this outbreak. These findings are useful for the establishment of a detailed control strategy for scrub typhus infection in previously unrecognized areas of Jiangsu Province, China.
The consumption of crops fertilized with human waste represents a potential route of exposure to antibiotic-resistant fecal bacteria. The present study evaluated the abundance of bacteria and antibiotic resistance genes by using both culture-dependent and molecular methods. Various vegetables (lettuce, carrots, radish, and tomatoes) were sown into field plots fertilized inorganically or with class B biosolids or untreated municipal sewage sludge and harvested when of marketable quality. Analysis of viable pathogenic bacteria or antibiotic-resistant coliform bacteria by plate counts did not reveal significant treatment effects of fertilization with class B biosolids or untreated sewage sludge on the vegetables. Numerous targeted genes associated with antibiotic resistance and mobile genetic elements were detected by PCR in soil and on vegetables at harvest from plots that received no organic amendment. However, in the season of application, vegetables harvested from plots treated with either material carried gene targets not detected in the absence of amendment. Several gene targets evaluated by using quantitative PCR (qPCR) were considerably more abundant on vegetables harvested from sewage sludge-treated plots than on vegetables from control plots in the season of application, whereas vegetables harvested the following year revealed no treatment effect. Overall, the results of the present study suggest that producing vegetable crops in ground fertilized with human waste without appropriate delay or pretreatment will result in an additional burden of antibiotic resistance genes on harvested crops. Managing human exposure to antibiotic resistance genes carried in human waste must be undertaken through judicious agricultural practice.
Background: Statins have proven efficacy in inhibiting the onset and progress of atherosclerosis. The effectiveness of pitavastatin in reversing carotid atherosclerosis associated with hypercholesterolemia (HC) is unknown. Objectives: To explore the simultaneous effects of pitavastatin calcium on brachial arterial flow-mediated vasodilatation (FMD), carotid intima-media thickness (IMT), and arterial stiffness (β), three surrogate markers of atherosclerosis were studied in HC patients. Methods: A randomized, double-blind trial was performed with 40 HC subjects who fulfilled the inclusion/exclusion criteria. Patients were given pitavastatin calcium 1 mg/d (Group 1) or 2 mg/d (Group 2) for 8 weeks. There were 20 patients in each group, and 30 gender- and age-matched healthy subjects as controls were recruited. FMD of the brachial artery, carotid IMT, and arterial stiffness indicated by β were measured at baseline and at 8 weeks after starting pitavastatin calcium therapy using ultrasound techniques. Biochemical tests were also made on all subjects. Results: At baseline, higher total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C), reduced FMD, and increased β and IMT were observed in HC patients (P<0.001 for all) compared with controls. After 8 weeks, TC was decreased by 20.59%/27.56% and LDL-C 30.92%/35.64%, respectively, in comparison to baseline groups; the HC groups had reduced β and improved endothelial function over the 8-week follow-up (P<0.05–0.001); nonetheless, no significant alterations of IMT were found (P>0.05). Significant negative interactions between TC/LDL and FMD (P<0.05–0.001), positive interactions between TC and IMT (P=0.003) and between TC/LDL and β (P<0.001–0.000) were found. Conclusions: Treatment with pitavastatin calcium exerted favorable effects on endothelial function and arterial stiffness. It also improved carotid atherosclerosis in patients with HC.
Flow-mediated vasodilatation (FMD); Hypercholesterolemia (HC); Carotid intima-media thickness (IMT); Pitavastatin calcium
Mechanical stimuli profoundly alter cell fate, yet the mechanisms underlying
mechanotransduction remain obscure due to a lack of methods for molecular force imaging.
Here, to address this need, we develop a new class of molecular tension probes that
function as a switch to generate a 20–30-fold increase in fluorescence upon
experiencing a threshold piconewton force. The probes employ immobilized DNA-hairpins with
tunable force response thresholds, ligands, and fluorescence reporters. Quantitative
imaging reveals that integrin tension is highly dynamic and increases with an increasing
integrin density during adhesion formation. Mixtures of fluorophore-encoded probes show
integrin mechanical preference for cyclized-RGD over linear-RGD peptides. Multiplexed
probes with variable guanine-cytosine content within their hairpins reveal integrin
preference for the more stable probes at the leading tip of growing adhesions near the
cell edge. DNA-based tension probes are among the most sensitive optical force reporters
to date, overcoming the force and spatial-resolution limitations of traction force
Mechanotransduction; Focal adhesion; FRET sensor; Force sensing
Alzheimer's disease (AD) is characterized by amyloid plaques consisting of β-amyloid (Aβ) peptides and neurofibrillary tangles consisting of hyperphosphorylated tau protein. Aβ is proteolytically derived from its precursor protein through cleavages by β-secretase and γ-secretase complex comprising presenilins (PS, PS1/PS2), nicastrin, APH-1 and PEN-2. PS1 is also known to activate the PI3K/Akt cell survival pathway in a γ-secretase-independent manner. The tumor suppressor PTEN, which antagonizes the PI3K/Akt pathway, has increasingly been recognized to play a key role in neural functions and its level found reduced in AD brains. Here, we demonstrate that the protein level of PTEN is dramatically reduced in cultured cells and embryonic tissues deficient of PS, and in the cortical neurons of PS1/PS2 conditional double knockout mice. Restoration of PS in PS deficient cells reverses the reduction of PTEN. Regulation of PTEN by PS is independent of the PS/γ-secretase activity since impaired γ-secretase by the γ-secretase inhibitor treatment or due to nicastrin deficiency has little effect on the protein level of PTEN. Our data suggest an important role for PS in signaling pathways involving PI3K/Akt and PTEN that are crucial for physiological functions and the pathogenesis of multiple diseases.
Akt; Alzheimer’s disease; phosphatase and tensin homologue deleted on chromosome 10; phosphoinositide 3-kinase; presenilin
Antigen-presentation genes play a vital role in the pathogenesis of HCV infection. However, the relationship of variants of these genes with spontaneous outcomes of HCV infection has not been fully investigated. To explore novel loci in the Chinese population, 34 tagging-SNPs in 9 candidate genes were genotyped for their associations with the outcomes of HCV infection. The distributions of different genotypes and haplotypes were compared among 773 HCV-negative controls, 246 subjects with HCV natural clearance, and 218 HCV persistent carriers recruited from hemodialysis patients and intravenous drug users. Our study implicated that TAP2, HLA-DOA, HLA-DOB, and tapasin loci were novel candidate regions for susceptibility to HCV infection and viral clearance in the Chinese population. Logistic regression analyses showed that TAP2 rs1800454 A (OR = 1.48, P = 0.002) and HLA-DOB rs2071469 G (OR = 1.23, P = 0.048) were significantly associated with increased susceptibility to establishment of HCV infection. However, high-risk behavior exposure and age were stronger predictors of HCV infection. Mutation of tapasin rs9277972 T (OR = 1.57, P =0.043) increased the risk of HCV chronicity, and HLA-DOA rs3128935 C (OR = 0.62, P = 0.019) increased the chance of viral resolution. With regards to the effect of rs3128925, interactions were found with high-risk behavior (P = 0.013) and age (P = 0.035). The risk effect of rs3128925 T for persistent HCV infection was higher in injecting drug users (vs. dialysis patients) and in subjects ≥ 40 years old (vs. < 40 years old).
Protease-activated receptor 4 (PAR4), a member of G-protein coupled receptors family, was recently reported to exhibit decreased expression in gastric cancer and esophageal squamous cancer, yet increased expression during the progression of prostate cancer. Trefoil factor 2 (TFF2), a small peptide constitutively expressed in the gastric mucosa, plays a protective role in restitution of gastric mucosa. Altered TFF2 expression was also related to the development of gastrointestinal cancer. TFF2 has been verified to promote cell migration via PAR4, but the roles of PAR4 and TFF2 in the progress of colorectal cancer are still unknown. In this study, the expression level of PAR4 and TFF2 in colorectal cancer tissues was measured using real-time PCR (n = 38), western blotting (n=38) and tissue microarrays (n = 66). The mRNA and protein expression levels of PAR4 and TFF2 were remarkably increased in colorectal cancer compared with matched noncancerous tissues, especially in positive lymph node and poorly differentiated cancers. The colorectal carcinoma cell LoVo showed an increased response to TFF2 as assessed by cell invasion upon PAR4 expression. However, after intervention of PAR4 expression, PAR4 positive colorectal carcinoma cell HT-29 was less responsive to TFF2 in cell invasion. Genomic bisulfite sequencing showed the hypomethylation of PAR4 promoter in colorectal cancer tissues and the hypermethylation in the normal mucosa that suggested the low methylation of promoter was correlated to the increased PAR4 expression. Taken together, the results demonstrated that the up-regulated expression of PAR4 and TFF2 frequently occurs in colorectal cancer tissues, and that overexpression of PAR4 may be resulted from promoter hypomethylation. While TFF2 promotes invasion activity of LoVo cells overexpressing PAR4, and this effect was significantly decreased when PAR4 was knockdowned in HT-29 cells. Our findings will be helpful in further investigations into the functions and molecular mechanisms of Proteinase-activated receptors (PARs) and Trefoil factor factors (TFFs) during the progression of colorectal cancer.
AIM: To determine the association between rapid viral response and IL28B, IL28RA, IL10RB and MxA polymorphisms in the Chinese Han population.
METHODS: The study cohort consisted of 238 chronic hepatitis C patients treated with interferon (IFN)-α-2b and ribavirin. Six single nucleotide polymorphisms were genotyped using the ABI TaqMan allelic discrimination assay. Biochemical indices were measured at baseline. Serum hepatitis C virus (HCV) RNA was detected at weeks 0, 4, 12 and 24 of therapy.
RESULTS: Only IL28B rs12980275 was associated with treatment response in the Chinese Han population. Patients carrying AG/GG genotypes had a reduced rapid viral response compared with patients carrying the AA genotype (additive model: adjusted OR = 0.43, 95%CI: 0.24-0.75). It took less time for patients with the AA genotype to achieve a viral load < 500 copies/mL (log-rank test, P = 0.004). In addition, the protective effect of genotype AA was independent of baseline viral load. HCV genotype, and baseline white blood cell count, α-fetoprotein and viral load might also help predict treatment response. The area under the receiver-operating characteristic curve was 0.726.
CONCLUSION: IL28B rs12980275 AA genotype is a strong predictor of positive response to IFN therapy in Chinese Han patients with hepatitis C.
Hepatitis C virus; Interferon; Rapid viral response; IL28B; Chinese population