The symptoms of major depression (MD) are clinically diverse. Do they form coherent factors that might clarify the underlying nature of this important psychiatric syndrome?
Symptoms at lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years with recurrent DSM-IV MD. Exploratory factor analysis (EFA) and confirmatoryfactor analysis (CFA) were performed in Mplus in random split-half samples.
The preliminary EFA results were consistently supported by the findings from CFA. Analyses of the nine DSM-IV MD symptomatic A criteria revealed two factors loading on: (i) general depressive symptoms; and (ii) guilt/suicidal ideation. Examining 14 disaggregated DSM-IV criteria revealed three factors reflecting: (i) weight/appetite disturbance; (ii) general depressive symptoms; and (iii) sleep disturbance. Using all symptoms (n = 27), we identified five factors that reflected: (i) weight/appetite symptoms; (ii) general retarded depressive symptoms; (iii) atypical vegetative symptoms; (iv) suicidality/hopelessness; and (v) symptoms of agitation and anxiety.
MD is a clinically complex syndrome with several underlying correlated symptom dimensions. In addition to a general depressive symptom factor, a complete picture must include factors reflecting typical/atypical vegetative symptoms, cognitive symptoms (hopelessness/suicidal ideation), and an agitated symptom factor characterized by anxiety, guilt, helplessness and irritability. Prior cross-cultural studies, factor analyses of MD in Western populations and empirical findings in this sample showing risk factor profiles similar to those seen in Western populations suggest that our results are likely to be broadly representative of the human depressive syndrome.
Atypical symptoms; China; cognitive symptoms; depression; factor analysis
Studies in Western countries have repeatedly shown that women with a history of childhood sexual abuse (CSA) are at increased risk for developing major depression (MD). Would this relationship be found in China?
Three levels of CSA (non-genital, genital, and intercourse) were assessed by self-report in two groups of Han Chinese women: 1970 clinically ascertained with recurrent MD and 2597 matched controls. Diagnostic and other risk factor information was assessed at personal interview. Odds ratios (ORs) were calculated by logistic regression and regression coefficients by linear or Poisson regression.
Any form of CSA was significantly associated with recurrent MD [OR 3.26, 95% confidence interval (CI) 1.95–5.45]. This association strengthened with increasing CSA severity: non-genital (OR 2.47, 95% CI 1.17–5.23), genital (OR 2.77, 95% CI 1.32–5.83) and intercourse (OR 13.35, 95% CI 1.83–97.42). The association between any form of CSA and MD remained significant after accounting for parental history of depression, childhood emotional neglect (CEN), childhood physical abuse (CPA) and parent–child relationship. Among the depressed women, those with CSA had an earlier age of onset, longer depressive episodes and an increased risk for generalized anxiety disorder (GAD; OR 1.92, 95% CI 1.39–2.66) and dysthymia (OR 2.16, 95% CI 1.52–3.09).
In Chinese women CSA is strongly associated with MD and this association increases with greater severity of CSA. Depressed women with CSA have an earlier age of onset, longer depressive episodes and increased co-morbidity with GAD and dysthymia. Although reporting biases cannot be ruled out, our results are consistent with the hypothesis that, as in Western countries, CSA substantially increases the risk for MD in China.
Childhood sexual abuse; co-morbidity; major depression
Previous studies support Beck's cognitive model of vulnerability to depression. However, the relationship between his cognitive triad and other clinical features and risk factors among those with major depression (MD) has rarely been systematically studied.
The three key cognitive symptoms of worthlessness, hopelessness and helplessness were assessed during their lifetime worst episode in 1970 Han Chinese women with recurrent MD. Diagnostic and other risk factor information was assessed at personal interview. Odds ratios (ORs) were calculated by logistic regression.
Compared to patients who did not endorse the cognitive trio, those who did had a greater number of DSM-IV A criteria, more individual depressive symptoms, an earlier age at onset, a greater number of episodes, and were more likely to meet diagnostic criteria for melancholia, postnatal depression, dysthymia and anxiety disorders. Hopelessness was highly related to all the suicidal symptomatology, with ORs ranging from 5.92 to 6.51. Neuroticism, stressful life events (SLEs) and a protective parental rearing style were associated with these cognitive symptoms.
During the worst episode of MD in Han Chinese women, the endorsement of the cognitive trio was associated with a worse course of depression and an increased risk of suicide. Individuals with high levels of neuroticism, many SLEs and high parental protectiveness were at increased risk for these cognitive depressive symptoms. As in Western populations, symptoms of the cognitive trio appear to play a central role in the psychopathology of MD in Chinese women.
Cognitive trio; Han Chinese women; major depression; suicide; symptoms
The objective of this study was to compare the image quality and radiation dose of chest CT images reconstructed with a blend of adaptive statistical iterative reconstruction (ASIR) and filtered back-projection (FBP) with images generated using conventional FBP.
Patients with chest CT re-examinations were alternately assigned to two scanners with different reconstruction techniques. The study groups included noise index (NI) 11 with 30% ASIR (A30), NI 13 with 40% ASIR (A40), NI 15 with 50% ASIR (A50) and NI 17 with 60% ASIR (A60), sequentially changed every 2 months. The control images were obtained using FBP and NI 11. All acquisitions were performed with automatic dose modulation. Paired t-test and non-parameter test were applied to compare the difference.
The radiation doses were significantly lower in the examinations that used ASIR (p<0.001). The mean dose reduction rate was 27.7%, 45.2%, 57.1% and 71.8% for Groups A30, A40, A50 and A60, respectively. The image quality of Groups A30–A50 was not inferior to that of the control examinations. The image noise of Group A60 was greater and subjective image quality was inferior to that of the control.
ASIR enabled the use of a higher NI with automatic dose modulation. With 50% ASIR and a NI of 15, the effective radiation dose was reduced by 57%, without compromising image quality.
The Ets transcription factor, Fli-1 is activated in murine erythroleukemia and overexpressed in various human malignancies including Ewing's sarcoma, induced by the oncogenic fusion protein EWS/Fli-1. Recent studies by our group and others have demonstrated that Fli-1 plays a key role in tumorigenesis, and disrupting its oncogenic function may serve as a potential treatment option for malignancies associated with its overexpression. Herein, we describe the discovery of 30 anti-Fli-1 compounds, characterized into six functional groups. Treatment of murine and human leukemic cell lines with select compounds inhibits Fli-1 protein or mRNA expression, resulting in proliferation arrest and apoptosis. This anti-cancer effect was mediated, at least in part through direct inhibition of Fli-1 function, as anti-Fli-1 drug treatment inhibited Fli-1 DNA binding to target genes, such as SHIP-1 and gata-1, governing hematopoietic differentiation and proliferation. Furthermore, treatment with select Fli-1 inhibitors revealed a positive relationship between the loss of DNA-binding activity and Fli-1 phosphorylation. Accordingly, anti-Fli-1 drug treatment significantly inhibited leukemogenesis in a murine erythroleukemia model overexpressing Fli-1. This study demonstrates the ability of this drug-screening strategy to isolate effective anti-Fli-1 inhibitors and highlights their potential use for the treatment of malignancies overexpressing this oncogene.
erythroleukemia; Fli-1; drug inhibition
We investigated common genetic variation in the entire ESR1 and EGF genes in relation to endometrial cancer risk, myometrial invasion and endometrial cancer survival. We genotyped a dense set of single-nucleotide polymorphisms (SNPs) in both genes and selected haplotype tagging SNPs (tagSNPs). The tagSNPs were genotyped in 713 Swedish endometrial cancer cases and 1567 population controls and the results incorporated into logistic regression and Cox proportional hazards models. We found five adjacent tagSNPs covering a region of 15 kb at the 5′ end of ESR1 that decreased the endometrial cancer risk. The ESR1 variants did not, however, seem to affect myometrial invasion or endometrial cancer survival. For the EGF gene, no association emerged between common genetic variants and endometrial cancer risk or myometrial invasion, but we found a five-tagSNP region that covered 51 kb at the 5′ end of the gene where all five tagSNPs seemed to decrease the risk of dying from endometrial cancer. One of the five tagSNPs in this region was in strong linkage disequilibrium (LD) with the untranslated A61G (rs4444903) EGF variant, earlier shown to be associated with risk for other forms of cancer.
ESR1; EGF; polymorphism; endometrial cancer; survival
We evaluated the survival benefit of providing concurrent chemoradiotherapy (ccrt) plus adjuvant chemotherapy compared with ccrt alone to patients with locally advanced nasopharyngeal carcinoma.
This retrospective study included 130 patients with nasopharyngeal carcinoma treated with ccrt plus adjuvant chemotherapy from June 2005 to December 2010. Another 130 patients treated with ccrt alone during the same period were matched on age, sex, World Health Organization histology, T stage, N stage, and technology used for radiotherapy. The endpoints included overall survival, locoregional failure-free survival, distant metastasis failure-free survival, and failure-free survival.
At a mean follow-up of 42.1 months (range: 8–85 months), the observed hazard ratios for the group receiving ccrt plus adjuvant chemotherapy compared with the group receiving ccrt alone were: for overall survival, 0.77 [95% confidence interval (ci): 0.37 to 1.57]; for locoregional failure-free survival, 1.00 (95% ci: 0.37 to 2.71); for distant metastasis failure-free survival, 1.15 (95% ci: 0.56 to 2.37); and for failure-free survival, 1.26 (95% ci: 0.69 to 2.28). There were no significant differences in survival between the groups. After stratification by disease stage, ccrt plus adjuvant chemotherapy provided a borderline significant benefit for patients with N2–3 disease (hazard ratio: 0.35; 95% ci: 0.11 to 1.06; p = 0.052). Multivariate analyses indicated that only tumour stage was a prognostic factor for overall survival.
Patients with locally advanced nasopharyngeal carcinoma received no significant survival benefit from the addition of adjuvant chemotherapy to ccrt. However, patients with N2–3 disease might benefit from the addition of adjuvant chemotherapy to ccrt.
Nasopharyngeal carcinoma; concurrent chemoradiotherapy; adjuvant chemotherapy
Finding biomarkers of human neurological diseases is one of the most pressing goals of modern medicine. Most neurological disorders are recognized too late because of the lack of biomarkers that can identify early pathological processes in the living brain. Late diagnosis leads to late therapy and poor prognosis. Therefore, during the past decade, a major endeavor of clinical investigations in neurology has been the search for diagnostic and prognostic biomarkers of brain disease. Recently, a new field of metabolomics has emerged, aiming to investigate metabolites within the cell/tissue/organism as possible biomarkers. Similarly to other “omics” fields, metabolomics offers substantial information about the status of the organism at a given time point. However, metabolomics also provides functional insight into the biochemical status of a tissue, which results from the environmental effects on its genome background. Recently, we have adopted metabolomics techniques to develop an approach that combines both in vitro analysis of cellular samples and in vivo analysis of the mammalian brain. Using proton magnetic resonance spectroscopy, we have discovered a metabolic biomarker of neural stem/progenitor cells (NPCs) that allows the analysis of these cells in the live human brain. We have developed signal-processing algorithms that can detect metabolites present at very low concentration in the live human brain and can indicate possible pathways impaired in specific diseases. Herein, we present our strategy for both cellular and systems metabolomics, based on an integrative processing of the spectroscopy data that uses analytical tools from both metabolomic and spectroscopy fields. As an example of biomarker discovery using our approach, we present new data and discuss our previous findings on the NPC biomarker. Our studies link systems and cellular neuroscience through the functions of specific metabolites. Therefore, they provide a functional insight into the brain, which might eventually lead to discoveries of clinically useful biomarkers of the disease.
Densoviruses are parvoviruses that can be lethal for insects of different orders at larval stages. Although the horizontal transmission mechanisms are poorly known, densoviral pathogenesis usually starts with the ingestion of contaminated food by the host. Depending on the virus, this leads to replication restricted to the midgut or excluding it. In both cases the success of infection depends on the virus capacity to enter the intestinal epithelium. Using the Junonia coenia densovirus (JcDNV) as the prototype virus and the lepidopteran host Spodoptera frugiperda as an interaction model, we focused on the early mechanisms of infection during which JcDNV crosses the intestinal epithelium to reach and replicate in underlying target tissues. We studied the kinetics of interaction of JcDNV with the midgut epithelium and the transport mechanisms involved. Using several approaches, in vivo, ex vivo, and in vitro, at molecular and cellular levels, we show that JcDNV is specifically internalized by endocytosis in absorptive cells and then crosses the epithelium by transcytosis. As a consequence, viral entry disturbs the midgut function. Finally, we showed that four mutations on the capsid of JcDNV affect specific recognition by the epithelial cells but not their binding.
A dedicated analytical scanning transmission electron microscope (STEM) with dual energy dispersive spectroscopy (EDS) detectors has been designed for complementary high performance imaging as well as high sensitivity elemental analysis and mapping of biological structures. The performance of this new design, based on a Hitachi HD-2300A model, was evaluated using a variety of biological specimens. With three imaging detectors, both the surface and internal structure of cells can be examined simultaneously. The whole-cell elemental mapping, especially of heavier metal species that have low cross-section for electron energy loss spectroscopy (EELS), can be faithfully obtained. Optimization of STEM imaging conditions is applied to thick sections as well as thin sections of biological cells under low-dose conditions at room- and cryogenic temperatures. Such multimodal capabilities applied to soft/biological structures usher a new era for analytical studies in biological systems.
ErbB2, an important membrane-bound receptor tyrosine kinase, was discovered nearly 30 years ago, but a natural ligand has never been found previously. ErbB2 is also an important oncogene and anticancer target, and its overexpression in cancer is associated with poor disease prognosis. Here, we report that human prolidase (PEPD) is a high affinity ligand of ErbB2 and binds as a homodimer to subdomain 3 in the extracellular domain of this receptor. In ErbB2-overexpressing cells, both ErbB2 monomers and activated dimers exist. PEPD bound to ErbB2 monomers relatively slowly but caused ErbB2 dimerization, ErbB2 phosphorylation and downstream signaling. In contrast, PEPD bound rapidly to ErbB2 homodimers and rapidly silenced ErbB2 dimer-Src signaling, a key oncogenic pathway of ErbB2, by disrupting the association of Src with ErbB2. PEPD also caused pronounced ErbB2 depletion, resulting from ErbB2 internalization and degradation. Moreover, PEPD strongly inhibited the DNA synthesis, anchorage-independent growth and invasion and migration of cells that overexpressed ErbB2 but had no effect on cells without ErbB2 overexpression. Cells became sensitized to PEPD upon achieving stable ErbB2 overexpression. Thus, the impact of PEPD on ErbB2 is predominantly inhibitory, and PEPD targets cells addicted to ErbB2. PEPD is also a dipeptidase, but its enzymatic function is not involved in ErbB2 modulation. These findings revise our understanding of ErbB2 and PEPD and may be especially important for combating ErbB2-positive cancers.
ErbB2; Her2; ErbB2 ligand; PEPD; prolidase
Zeaxanthin (Zea) is a major carotenoid pigment contained in human retina, and its daily supplementation associated with lower risk of age-related macular degeneration. Despite known property of Zea as an antioxidant, its underlying molecular mechanisms of action remain poorly understood. In this study, we aim to study the regulation mechanism of Zea on phase II detoxification enzymes. In normal human retinal pigment epithelium cells, Zea promoted the nuclear translocation of NF-E2-related factor 2 (Nrf2) and induced mRNA and protein expression of phase II enzymes, the induction was suppressed by specific knockdown of Nrf2. Zea also effectively protected against tert-butyl hydroperoxide-induced mitochondrial dysfunction and apoptosis. Glutathione (GSH) as the most important antioxidant was also induced by Zea through Nrf2 activation in a time- and dose-dependent manner, whereas the protective effects of Zea were decimated by inhibition of GSH synthesis. Finally, Zea activated the PI3K/Akt and MAPK/ERK pathway, whereas only PI3K/Akt activation correlated with phase II enzymes induction and Zea protection. In further in vivo analyses, Zea showed effects of inducing phase II enzymes and increased GSH content, which contributed to the reduced lipid and protein peroxidation in the retina as well as the liver, heart, and serum of the Sprague–Dawley rats. For the first time, Zea is presented as a phase II enzymes inducer instead of being an antioxidant. By activating Nrf2-mediated phase II enzymes, Zea could enhance anti-oxidative capacity and prevent cell death both in vivo and in vitro.
zeaxanthin; glutathione; reactive oxygen species; Nrf2; mitochondria
The autophagic process involves encompassing damaged proteins and organelles within double- or multi-membraned structures and delivering these molecules to the lytic compartments of vacuoles. Sphingolipids (SLs), which are ubiquitous membrane lipids in eukaryotes, participate in the generation of various membrane structures, including rafts, caveolae, and cytosolic vesicles. SLs are a complex family of molecules that have a growing number of members, including ceramide, sphingosine-1-phosphate, and dihydroceramide, which have been associated with the essential cellular process of autophagy. This review highlights recent studies focusing on the regulation and function of SL-associated autophagy and its role in cell fate, diseases, and therapeutic interventions.
autophagy; sphingolipids; sphingolipidoses; sphingolipid rheostat; sphingolipid biostat
Rasfonin is a novel 2-pyrone derivative reported to induce apoptosis in ras-dependent cells. In this study, its effects on ras-mutated pancreatic cancer cells were investigated in vitro and in vivo. Two human pancreatic cancer cell lines Panc-1 (mutated K-ras) and BxPC-3 (wild-type K-ras) were selected to test the effects of rasfonin on cell proliferation, clone formation, migration and invasion in vitro. Immunoblotting was used to detect the expressions of EGFR–Ras–Raf–MEK–ERK signaling pathway proteins. Ras activity was measured using a pull-down ELISA kit and guanine exchange factor (GEF)/GTPase-activating proteins (GAP) activity was measured by [3H]-GDP radiometric ligand binding. For an in vivo study, CD1 nude mice bearing Panc-1 cells were treated with rasfonin or Salirasib (FTS). We found that rasfonin suppressed proliferation more strongly in Panc-1 cells (IC50=5.5 μM) than BxPC-3 cells (IC50=10 μM) in vitro. Clone formation, migration and invasion by Panc-1 cells were also reduced by rasfonin. Rasfonin had little effect on the farnesylation of Ras, but it strongly downregulated Ras activity and consequently phosphorylation of c-Raf/MEK/ERK. Further experiments indicated that rasfonin reduced Son of sevenless (Sos1) expression but did not alter GEF and GAP activities. The in vivo experiments also revealed that rasfonin (30 mg/kg) delayed the growth of xenograft tumors originating from Panc-1 cells. Tumor weight was ultimately decreased after 20 days of treatment of rasfonin. Rasfonin is a robust inhibitor of pancreatic cancers with the K-ras mutation. The reduction of Sos1 expression and the consequently depressed Ras–MAPK activity could be important in its anticancer activity.
rasfonin; ras; pancreatic cancer; sos1; Panc-1 cell
We propose a novel semiconductor compatible path for nano-graphene synthesis using precursors containing C-Br bonding and liquid catalyst. The unique combination of CBr4 as precursor and Ga as catalyst leads to efficient C precipitation at a synthesis temperature of 200°C or lower. The non-wetting nature of liquid Ga on tested substrates limits nano-scale graphene to form on Ga droplets and substrate surfaces at low synthesis temperatures of T ≤ 450°C and at droplet/substrate interfaces by C diffusion via droplet edges when T ≥ 400°C. Good quality interface nano-graphene is demonstrated and the quality can be further improved by optimization of synthesis conditions and proper selection of substrate type and orientation. The proposed method provides a scalable and transfer-free route to synthesize graphene/semiconductor heterostructures, graphene quantum dots as well as patterned graphene nano-structures at a medium temperature range of 400–700°C suitable for most important elementary and compound semiconductors.
To assess the effective dose of the liver C-arm computed tomography (CT) scan during hepatic arterial embolisation surgery with clinical dose–area product (DAP) data from Taiwan.
The experiment used two kinds of phantoms: RANDO® Man and RANDO Woman (The Phantom Laboratory, Salem, NY), embedded with thermoluminescent dosemeters at locations according to the International Commission on Radiological Protection 103 report. The conversion factors of DAP to effective doses for males and females, respectively, were obtained. The clinical DAP data of liver C-arm CT scan during hepatic arterial embolisation surgery were collected in a hospital in Taiwan.
There were 125 liver transarterial embolisation therapy cases, including 94 males and 31 females, from February 2009 to June 2010. C-arm CT was used 38 times for males and 17 times for females. The corresponding average and standard deviation of clinical DAP were 61.0±6.6 Gy cm2 and 52.2±8.3 Gy cm2, respectively.
The DAP of RANDO Man and RANDO Woman phantoms simply scanned by C-arm CT are much lower than that of patients. After consideration of the clinical DAP of patients, the effective doses of a liver C-arm CT scan recommended for males and females in Taiwan are 11.5±2.3 mSv and 11.3±3.0 mSv, respectively.
Advances in knowledge:
The conversion factors of DAP to effective doses for males and females are 0.19±0.03 mSv Gy−1 cm−2 and 0.22±0.05 mSv Gy−1 cm−2. Only if the actual DAP value of a patient scan is multiplied by the conversion factor can the correct effective dose be determined.
Transcription factors of the RUNX family (RUNXs), which play pivotal roles in normal development and neoplasia, are regulated by various post-translational modifications. To understand the molecular mechanisms underlying the regulation of RUNXs, we performed a large-scale functional genetic screen of a fly mutant library. The screen identified dPias (the fly ortholog of mammalian PIASs), an E3 ligase for the SUMO (small ubiquitin-like modifier) modification, as a novel genetic modifier of lz (the fly ortholog of mammalian RUNX3). Molecular biological analysis revealed that lz/RUNXs are sumoylated by dPias/PIAS1 at an evolutionarily conserved lysine residue (K372 of lz, K144 of RUNX1, K181 of RUNX2 and K148 of RUNX3). PIAS1-mediated sumoylation inhibited RUNX3 transactivation activity, and this modification was promoted by the AKT1 kinase. Importantly, PIAS1 failed to sumoylate some RUNX1 mutants associated with breast cancer. In nude mice, tumorigenicity was promoted by RUNX3 bearing a mutation in the sumoylation site, but suppressed by wild-type RUNX3. Our results suggest that RUNXs are sumoylated by PIAS1, and that this modification could play a critical role in the regulation of the tumor-suppressive activity of these proteins.
RUNX3; PIAS1; AKT1; sumoylation; tumor suppressor
Interleukin-1α(IL-1α) is a powerful activator of osteoclast cells. However, the underlying mechanism for this activation is unknown. In this study, we reveal that IL-1α up-regulates the expression of cathepsin K protein, a key protease in bone resorption, by five-fold. Northern blot analysis and promoter analysis show that this induction occurs at the transcriptional level, in a dose-responsive and time-dependent manner. No increase in expression occurs in the presence of either pyrrolidine dithiocarbamate (PDTC), a selective inhibitor of NF-κB, or Genistein, a protein tyrosine kinase inhibitor, suggesting that IL-1α up-regulation may be via the tyrosine kinase-NF-κB pathway to regulate cathepsin K expression. Antisense oligonucleotides to p65, but not the p50 subunit of NF-κB, suppress the IL-1α-induced expression of cathepsin K. We therefore conclude that IL-1α up-regulates cathepsin K gene expression at the transcription level, and this regulation may be via the tyrosine-kinase-NF-κB pathway.
interleukin-1alpha; cathepsin K; osteoclast; NF-κB; tyrosine kinase
Transforming growth factor (TGF)-β1 produced in airway epithelia has been suggested as a contributor to the airway remodeling observed in asthma patients. The protein tyrosine phosphatase SHP2 is a demonstrable modulator of TGF-β1 production and thus a potential regulator of airway remodeling.
To define the signal event by which SHP2 regulates asthmatic responses in airway epithelial cells by using a mouse model of experimental OVA-induced airway remodeling.
The airways of Shp2flox/flox mice were infected with recombinant adenovirus vectors expressing a Cre recombinase–green fluorescence protein (GFP) fusion protein as part of allergen provocation studies using mice sensitized with ovalbumin (OVA) and repeatedly challenged with OVA. Several endpoint pathologies were assessed, including airway hyper-responsiveness (AHR), lung inflammatory score, peribronchial collagen deposition, and α-smooth muscle actin (SMA) hyperplasia. In vitro studies using airway epithelial cells (BEAS-2B) were used to investigate the role of SHP2 in the regulation of pulmonary remodeling events, including the expression of collagen, α-SMA, and TGF-β1.
Chronic OVA challenges in wild-type mice resulted in airway remodeling and lung dysfunction (e.g., increased inflammatory scores, collagen deposition (fibrosis), smooth muscle hyperplasia, and a significant increase in AHR). These endpoint pathology metrics were each significantly attenuated by conditional shp2 gene knockdown in airway epithelia. In vitro studies using BEAS-2B cells also demonstrated that the level of TGF-β1 production by these cells correlated with the extent of shp2 gene expression.
SHP2 activities in airway epithelial cells appear to modulate TGF-β1 production and, in turn, regulate allergic airway remodeling following allergen provocation.
Our findings identify SHP2 as a previously underappreciated contributor to the airway remodeling and lung dysfunction associated with allergen challenge. As such, SHP2 represents a potentially novel therapeutic target for the treatment of asthmatics.
airway epithelia; asthma; mice; protein tyrosine phosphatase SHP2; remodeling
In osteoarthritis (OA), adult articular chondrocytes undergo phenotypic modulation in response to alterations in the environment owing to mechanical injury and inflammation. These processes not only stimulate the production of enzymes that degrade the cartilage matrix but also inhibit repair. With the use of in vitro and in vivo models, new genes, not known previously to act in cartilage, have been identified and their roles in chondrocyte differentiation during development and in dysregulated chondrocyte function in OA have been examined. These new genes include growth arrest and DNA damage (GADD)45β and the epithelial-specific ETS (ESE)-1 transcription factor, induced by bone morpho-genetic protein (BMP)-2 and inflammatory cytokines, respectively. Both genes are induced by NF-κB, suppress COL2A1 and upregulate matrix meatalloproteinase-13 (MMP-13) expression. These genes have also been examined in mouse models of OA, in which discoidin domain receptor 2 is associated with MMP-13-mediated remodelling, in order to understand their roles in physiological cartilage homoeostasis and joint disease.
Studies have indicated that early-life or early-onset depression is associated with a 2- to 4-fold increased risk of developing Alzheimers disease (AD). In AD, aggregation of an abnormally phosphorylated form of the tau protein may be a key pathological event. Tau is known to play a major role in promoting microtubule assembly and stabilization, and in maintaining the normal morphology of neurons. Several studies have reported that stress may induce tau phosphorylation. The main aim of the present study was to investigate possible alterations in the tau protein in the hippocampus and frontal cortex of 32 male Sprague-Dawley rats exposed to chronic unpredictable mild stress (CUMS) and then re-exposed to CUMS to mimic depression and the recurrence of depression, respectively, in humans. We evaluated the effects of CUMS, fluoxetine, and CUMS re-exposure on tau and phospho-tau. Our results showed that a single exposure to CUMS caused a significant reduction in sucrose preference, indicating a state of anhedonia. The change in behavior was accompanied by specific alterations in phospho-tau protein levels, but fluoxetine treatment reversed the CUMS-induced impairments. Moreover, changes in sucrose preference and phospho-tau were more pronounced in rats re-exposed to CUMS than in those subjected to a single exposure. Our results suggest that changes in tau phosphorylation may contribute to the link between depression and AD.
Alzheimers disease; Depression; Tau; Chronic unpredictable mild stress (CUMS); Re-exposure to CUMS; Fluoxetine
While activation of the Notch pathway is observed in many human cancers, it is unknown whether elevated Notch1 expression is sufficient to initiate tumorigenesis in most tissues. To test the oncogenic potential of Notch1 in solid tumors, we expressed an activated form of NOTCH1 (N1ICD) in the developing mouse brain. N1ICD;hGFAP-cre mice were viable but developed severe ataxia and seizures, and died by weaning age. Analysis of transgenic embryonic brains revealed that N1ICD expression induced p53-dependent apoptosis. When apoptosis was blocked by genetic deletion of p53, 30~40% of N1ICD;GFAP-cre;p53+/− and N1ICD;GFAP-cre;p53−/− mice developed spontaneous medulloblastomas. Interestingly, Notch1-induced medulloblastomas most closely resembled the sonic hedgehog (SHH) subgroup of human medulloblastoma at the molecular level. Surprisingly, N1ICD-induced tumors do not maintain high levels of the Notch pathway gene expression, except for Notch2, demonstrating that initiating oncogenic events may not be decipherable by analyzing growing tumors in some cases. In summary, this study demonstrates that Notch1 has an oncogenic potential in the brain when combined with other oncogenic hits, such as p53 loss, and provides a novel mouse model of medulloblastoma.
The effectiveness of current treatment for age related macular degeneration (AMD) by targeting one molecule is limited due to its multifactorial nature and heterogeneous pathologies. Treatment strategy to target multiple signaling pathways or pathological components in AMD pathogenesis is under investigation for better clinical outcome. Inhibition of the redox function of apurinic endonuclease 1/redox factor-1 (APE1) was found to suppress endothelial angiogenesis and promote neuronal cell recovery, thereby may serve as a potential treatment for AMD. In the current study, we for the first time have found that a specific inhibitor of APE1 redox function by a small molecule compound E3330 regulates retinal pigment epithelium (RPEs) cell response to oxidative stress. E3330 significantly blocked sub-lethal doses of oxidized low density lipoprotein (oxLDL) induced proliferation decline and senescence advancement of RPEs. At the same time, E3330 remarkably decreased the accumulation of intracellular reactive oxygen species (ROS) and down-regulated the productions of monocyte chemoattractant protein-1 (MCP-1) and vascular endothelial growth factor (VEGF), as well as attenuated the level of nuclear factor-κB (NF-κB) p65 in RPEs. A panel of stress and toxicity responsive transcription factors that were significantly upregulated by oxLDL was restored by E3330, including Nrf2/Nrf1, p53, NF-κB, HIF1, CBF/NF-Y/YY1, and MTF-1. Further, a single intravitreal injection of E3330 effectively reduced the progression of laser-induced choroidal neovascularization (CNV) in mouse eyes. These data revealed that E3330 effectively rescued RPEs from oxidative stress induced senescence and dysfunctions in multiple aspects in vitro, and attenuated laser-induced damages to RPE–Bruch׳s membrane complex in vivo. Together with its previously established anti-angiogenic and neuroprotection benefits, E3330 is implicated for potential use for AMD treatment.
•Specific inhibition of APE1/Ref-1 redox function with E3330 blocked RPE proliferation decline and senescence-like phenotype advancement induced by oxLDL.•E3330 suppressed intracellular ROS, down-regulated the MCP-1 and VEGF production, and reduced nuclear NF-κB p65 in RPEs.•E3330 repressed the redox sensitive transcription factors Nrf2/Nrf1, p53, NF-κB, HIF1, CBF/NF-Y/YY1, and MTF-1 that stimulated by oxLDL in RPEs.•Intravitreal injection of E3330 markedly reduced the laser-induced CNV in mouse eyes.•E3330 holds great potential for the management of AMD.
AhR, aryl hydrocarbon receptor; AMD, age related macular degeneration; AP-1, activator protein 1; APE1, apurinic endonuclease 1/redox factor-1; ApoE, apolipoprotein E; CBF/NF-Y/YY1, CCAAT binding factor/nuclear factor-Y/Yin Yang 1; CECs, choroidal endothelial cells; CNV, choroidal neovascularization; DCFH-DA, dichlorodihydrofluorescin diacetate; DMSO, dimethylsulphoxide; Fluc, firefly luciferase; HIF-1α, hypoxia inducible factor-1α; HSF1, heat-shock factor 1; IκB-α, inhibitory NF-κB-α; MCP-1, monocyte chemoattractant protein-1; MTF1, metal regulatory transcription factor 1; NF-κB, nuclear factor-κB; Nox, NADPH oxidase; Nrf, nuclear factor erythroid-2-related factor; oxLDL, oxidized low density lipoprotein; redox, reduction/oxidation; Rluc, renilla luciferase; RNV, retinal neovascularization; ROS, reactive oxygen species; RPE, retinal pigment epithelium; RVECs, retinal vascular endothelial cells; SA-β-gal, senescence associated β-gal; SDS-PAGE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis; TUNEL, TdT mediated dUTP-fluorescein nick end-labeling; VEGF, vascular endothelial growth factor; APE1/Ref-1redox function; E3330; Oxidative stress; Retinal pigment epithelial cell; Transcription factor; Age-related macular degeneration.
The development of malignant prostate cancer involves multiple genetic alterations. For example, alterations in both survivin and p53 are reported to have crucial roles in prostate cancer progression. However, little is known regarding the interrelationships between p53 and survivin in prostate cancer. Our data demonstrate that the expression of survivin is inversely correlated with that of wtp53 protein (rs=0.548) in prostate cancer and in normal prostate tissues. We have developed a therapeutic strategy, in which two antitumor factors, small interfering RNA-survivin and p53 protein, are co-expressed from the same plasmid, and have examined their effects on the growth of PC3, an androgen-independent prostate cancer cell line. When p53 was expressed along with a survivin-specific short hairpin RNA (shRNA), tumor cell proliferation was significantly suppressed and apoptosis occurred. In addition, this combination also abrogated the expression of downstream target molecules such as cyclin-dependent kinase 4 and c-Myc, while enhancing the expression of GRIM19. These changes in gene expression occurred distinctly in the presence of survivin-shRNA/wtp53 compared with control or single treatment groups. Intratumoral injection of the co-expressed construct inhibited the growth and survival of tumor xenografts in a nude mouse model. These studies revealed evidence of an interaction between p53 and survivin proteins plus a complex signaling network operating downstream of the wtp53-survivin pathway that actively controls tumor cell proliferation, survival and apoptosis.
prostate cancer; p53; survivin; siRNA