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1.
Sleep Med Rev ; 73: 101877, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38006755

ABSTRACT

The effect of various exercise modalities on people with sleep disorders remains unclear. This network meta-analysis aims to explore the effects of various exercise modalities in improving sleep quality in people with sleep disorders. Four electronic databases were searched from inception to April 8, 2023. We conducted pairwise meta-analyses and frequentist network meta-analyses with random effects models. A total of 17 randomized controlled trials enrolled 1090 participants were included. Compared with passive control, with moderate-to-low certainty of evidence, mind-body exercise combined with treatment as usual [standard mean difference (SMD) = -2.26, 95% confidence interval (CI) (-3.29, -1,24)], moderate aerobic exercise combined with light strength exercise [SMD = -1.26, 95% CI (-2.22, -0.31)], mind-body exercise [SMD = -0.81, 95% CI (-1.37, -0.25)] and moderate aerobic exercise [SMD = -0.75, 95% CI (-1.38, -0.13)] were more effect in improving sleep disorders. Various exercise modalities have favorable effects on sleep quality for people with sleep disorders compared with passive control. However, due to the low quality of evidence, well-designed trials should be conducted to elucidate these promising findings in the future.


Subject(s)
Exercise , Sleep Quality , Sleep Wake Disorders , Humans , Exercise Therapy , Network Meta-Analysis , Randomized Controlled Trials as Topic , Sleep Wake Disorders/therapy
2.
BMC Med ; 21(1): 378, 2023 09 29.
Article in English | MEDLINE | ID: mdl-37775745

ABSTRACT

BACKGROUND: Although non-pharmacological smoking cessation measures have been widely used among smokers, current research evidence on the effects of smoking cessation is inconsistent and of mixed quality. Moreover, there is a lack of comprehensive evidence synthesis. This study seeks to systematically identify, describe, and evaluate the available evidence for non-pharmacological interventions in smoking populations through evidence mapping (EM), and to search for best-practice smoking cessation programs. METHODS: A comprehensive search for relevant studies published from the establishment of the library to January 8, 2023, was conducted in PubMed, Web of Science, Embase, the Cochrane Library, CNKI, CBM, Wan Fang, and VIP. Two authors independently assessed eligibility and extracted data. The PRISMA statement and AMSTAR 2 tool were used to evaluate the report quality and methodology quality of systematic reviews/meta-analyses (SRs/MAs), respectively. Bubble plots were utilized to display information, such as the study population, intervention type, evidence quality, and original study sample size. RESULTS: A total of 145 SRs/MAs regarding non-pharmacological interventions for smoking cessation were investigated, with 20 types of interventions identified. The most commonly used interventions were cognitive behaviour education (n = 32, 22.07%), professional counselling (n = 20, 13.79%), and non-nicotine electronic cigarettes (e-cigarettes) (n = 13, 8.97%). Among them, counselling and behavioural support can improve smoking cessation rates, but the effect varies depending on the characteristics of the support provided. These findings are consistent with previous SRs/MAs. The general population (n = 108, 74.48%) was the main cohort included in the SRs/MAs. The total score of PRISMA for the quality of the reports ranged from 8 to 27, and 13 studies (8.97%) were rated as high confidence, and nine studies (6.21%) as moderate confidence, in the AMSTAR 2 confidence rating. CONCLUSIONS: The abstinence effect of cognitive behaviour education and money incentive intervention has advantages, and non-nicotine e-cigarettes appear to help some smokers transition to less harmful replacement tools. However, the methodological shortcomings of SRs/MAs should be considered. Therefore, to better guide future practice in the field of non-pharmacological smoking cessation, it is essential to improve the methodological quality of SRs and carry out high-quality randomized controlled trials (RCTs).


Subject(s)
Electronic Nicotine Delivery Systems , Smoking Cessation , Humans , Counseling , Smoking/epidemiology , Smoking Cessation/methods , Smoking Prevention , Systematic Reviews as Topic , Meta-Analysis as Topic
4.
Chem Sci ; 14(25): 6936-6942, 2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37389243

ABSTRACT

Manipulating fluorescence by photo-switched spin-state conversions is an attractive prospect for applications in smart magneto-optical materials and devices. The challenge is how to modulate the energy transfer paths of the singlet excited state by light-induced spin-state conversions. In this work, a spin crossover (SCO) FeII-based fluorophore was embedded into a metal-organic framework (MOF) to tune the energy transfer paths. Compound 1 {Fe(TPA-diPy)[Ag(CN)2]2}·2EtOH (1) has an interpenetrated Hofmann-type structure, wherein the FeII ion is coordinated by a bidentate fluorophore ligand (TPA-diPy) and four cyanide nitrogen atoms and acts as the fluorescent-SCO unit. Magnetic susceptibility measurements revealed that 1 underwent an incomplete and gradual spin crossover with T1/2 = 161 K. Photomagnetic studies confirmed photo-induced spin state conversions between the low-spin (LS) and high-spin (HS) states, where the irradiation of 532 and 808 nm laser lights converted the LS and HS states to the HS and LS states, respectively. Variable-temperature fluorescence spectra study revealed an anomalous decrease in emission intensity upon the HS → LS transition, confirming the synergetic coupling between the fluorophore and SCO units. Alternating irradiation of 532 and 808 nm laser lights resulted in reversible fluorescence intensity changes, confirming spin state-controlled fluorescence in the SCO-MOF. Photo-monitored structural analyses and UV-vis spectroscopic studies demonstrated that the photo-induced spin state conversions changed energy transfer paths from the TPA fluorophore to the metal-centered charge transfer bands, ultimately leading to the switching of fluorescence intensities. This work represents a new prototype compound showing bidirectional photo-switched fluorescence by manipulating the spin states of iron(ii).

5.
Chemistry ; 29(45): e202301262, 2023 Aug 10.
Article in English | MEDLINE | ID: mdl-37272418

ABSTRACT

Cyano-bridged 4d-4f molecular nanomagnets have re-called increasing research interests in molecular magnetism since they offer more possibilities in achieving novel nanomagnets with versatile structures and magnetic interactions. In this work, four ß-diketone ligands bearing different substitution N-sites were designed and synthesized, namely 1-(2-pyridyl)-3-(3-pyridyl)-1,3-propanedione (HL1 ), 1,3-Bis (3-pyridyl)-1,3-propanedione (HL2 ), 1-(4-pyridyl)-3-(3-pyridyl)-1,3-propanedione (HL3 ), and 1,3-Bis (4-pyridyl)-1,3-propanedione (HL4 ), to tune the magnetic relaxation behaviors of cyano-bridged {DyIII MoV } systems. By reacting with DyCl3 ⋅ 6H2 O and K4 Mo(CN)8 ⋅ 2H2 O, four cyano-bridged complexes, namely {[Dy[MoV (CN)8 ](HL1 )2 (H2 O)3 ]} ⋅ 6H2 O (1), {[Dy[MoV (CN)8 ](HL2 )(H2 O)3 (CH3 OH)]}2 ⋅ 2CH3 OH ⋅ 3H2 O (2), {[Dy[MoV (CN)8 ](HL3 )(H2 O)2 (CH3 OH)] ⋅ H2 O}n (3), and {[Dy[MoV (CN)8 ](HL4 )2 (H2 O)3 ]} ⋅ 2H2 O⋅CH3 OH (4) were obtained. Structural analyses revealed that 1 and 4 are binuclear complexes, 2 has a tetragonal structure, and 3 exhibits a stair-like polymer chain structure. The DyIII ions in all complexes have eight-coordinated configurations with the coordination spheres DyO7 N1 for 1 and 4, DyO6 N2 for 2, and DyO5 N3 for 3. Magnetic measurements indicate that 1 is a zero-field single-molecule magnet (SMM) and complexes 2-4 are field-induced SMMs, with complex 4 featuring a two-step relaxation process. The magnetic characterizations and ab initio calculations revealed that changing the N-sites in the ß-diketone ligands can effectively alter the structures and magnetic properties of cyano-bridged 4d-4f nanomagnets by adjusting the coordination environments of the DyIII centers.

6.
Angew Chem Int Ed Engl ; 62(28): e202302815, 2023 Jul 10.
Article in English | MEDLINE | ID: mdl-37178444

ABSTRACT

Colossal and anisotropic thermal expansion is a key function for microscale or nanoscale actuators in material science. Herein, we present a hexanuclear compound of [(Tp*)FeIII (CN)3 ]4 [FeII (Ppmp)]2 ⋅2 CH3 OH (1, Tp*=hydrotris(3,5-dimethyl-pyrazol-1-yl)borate and Ppmp=2-[3-(2'-pyridyl)pyrazol-1-ylmethyl]pyridine), which has a rhombic core structure abbreviated as {FeIII 2 FeII 2 }. Magnetic susceptibility measurements and single-crystal X-ray diffraction analyses revealed that 1 underwent thermally-induced spin transition with the thermal hysteresis. The FeII site in 1 behaved as a spin crossover (SCO) unit, and significant deformation of its octahedron was observed during the spin transition process. Moreover, the distortion of the FeII centers actuated anisotropic deformation of the rhombic {FeIII 2 FeII 2 } core, which was spread over the whole crystal through the subsequent molecular rearrangements, leading to the colossal anisotropic thermal expansion. Our results provide a rational strategy for realizing the colossal anisotropic thermal expansion and shape memory effects by tuning the magnetic bistability.

7.
Chin Med ; 18(1): 38, 2023 Apr 10.
Article in English | MEDLINE | ID: mdl-37038228

ABSTRACT

BACKGROUND AND OBJECTIVE: Considering that physicians and patients widely use acupuncture, it is necessary to explore its adverse effects during treatment. Herein, an evidence map was generated based on published studies to identify acupuncture-induced adverse effects and assess their severity, with the overarching goal of providing references for safe and effective implementation. METHODS: A comprehensive literature search was performed in four public databases (PubMed, Embase, Web of science, and the Cochrane Library) to identify relevant studies published up to 15th June 2022. In addition, relevant studies were explored in the Epistemonikos database and reference lists were retrieved as a supplement. A MeaSurement Tool to Assess systematic Reviews, Version 2 (AMSTAR-2) quality assessment tool was applied to determine the methodological quality of included systematic reviews (SRs) and/or meta-analysis (MAs), whereas Microsoft Excel 2019 tool was used for data extraction and coding. Heatmaps were generated to display disease type, countries of origin for the first authors, and the sample sizes of original studies. Moreover, bubble charts comprehensively presented intervention categories, adverse reaction types, and evidence levels. RESULTS: A total of 535 SRs involving 33 adverse reactions were included. Among them, 22 studies were rated as high quality, 28 as moderate, 106 as low, and the rest were of critically-low quality. Numerous adverse effects were described in the studies, including syncope (86 SRs), organ or tissue injury (233 SRs), systemic reactions (113 SRs), infection (19 SRs), and other adverse events (373 SRs). Importantly, these adverse reactions were mainly associated with 19 acupuncture techniques, including electroacupuncture (n = 67), manual acupuncture (n = 47) and acupoint catgut embedding (n = 41). Furthermore, the 535 SRs described 23 diseases, among which symptoms, signs or clinical findings (83 SRs), mental, behavioral or neurodevelopmental disorders (67 SRs), and diseases of the nervous system (66 SRs) had the highest incidence. CONCLUSION: This evidence mapping explores the adverse effects of acupuncture, showing that there are multiple types of adverse reactions to acupuncture, with milder symptoms. The methodological assessment revealed that most of the included studies were of low- or critically low-quality. Therefore, there is a need for future randomized controlled trials and SRs to comprehensively analyze acupuncture-related adverse events in order to provide reliable and credible evidence.

8.
Dalton Trans ; 52(16): 5169-5175, 2023 Apr 25.
Article in English | MEDLINE | ID: mdl-36961301

ABSTRACT

Investigating spin crossover (SCO)-fluorescence bifunctional materials and establishing their structure-function relationships are attractive topics in chemistry and materials science. However, it remains challenging to preserve the fluorescence and SCO properties simultaneously in aggregated solid states. Herein, we design an (E)-2,6-bis(1H-pyrazol-1-yl)-4-(4-(1,2,2-triphenylvinyl)styryl)pyridine (tpe-bpp) ligand, which contains coordinated SCO and fluorescence units of an aggregation-induced emission luminogen (AIEgen). The coordination of the tpe-bpp ligand with different FeII salts generated three mononuclear complexes: [Fe(tpe-bpp)2](ClO4)2·5.75CH2Cl2 (1), [Fe(tpe-bpp)2](ClO4)2·CH2Cl2·3CH3OH (2) and [Fe(tpe-bpp)2](BF4)2·CH2Cl2·3CH3OH (3). Single-crystal X-ray diffraction studies showed that they shared a similar [Fe(tpe-bpp)2]2+ complex cation. Their counterions and co-crystallized solvents were different. Magnetic measurements revealed that 1, 2, and 3 exhibited a complete SCO behavior with the transition temperatures T1/2 of 375, 260, and 248 K, respectively. Fluorescence measurements confirmed the existence of the AIE property for both the tpe-bpp ligand and Fe(II) complexes. A monotonic decrease of the photoluminescence (PL) intensity upon increasing the temperature was behavior observed for all three complexes.

9.
Angew Chem Int Ed Engl ; 61(45): e202208208, 2022 Nov 07.
Article in English | MEDLINE | ID: mdl-36103279

ABSTRACT

Molecular materials possessing photo-tunable polarization switching is promising for optical switches, smart sensors, and data storage devices. However, it is challenging to devise a molecular material featuring simultaneous switchable magnetic and dielectric properties with regard to non-invasive and convenient light stimulus. Herein, we report a new Hofmann-type metal-organic framework (MOF) {Fe(bpt)[Pt(CN)4 ]} ⋅ 0.5anth (1, bpt=2,5-bis(4-pyridyl)thiophen; anth=anthracene), which displays thermo- and photo-switchable magnetic and dielectric properties. Photo-monitored structural analyses revealed that it was the photo-induced deformation of FeII coordination sphere and relative movement of guest anthracene that resulted in the variation of the local electric dipoles. These findings provide a new strategy to realize polarization switching through the light-induced spin crossover, and would be of fundamental significance for future photo-switchable and multifunctional materials.

10.
Nutrients ; 14(12)2022 Jun 15.
Article in English | MEDLINE | ID: mdl-35745212

ABSTRACT

To perform a systematic review and meta-analysis to evaluate the effectiveness and safety of probiotics in the treatment of constipation-predominant irritable bowel syndrome (IBS-C), we searched for randomized controlled trials (RCTs) comparing probiotic care versus placebos for patients with IBS-C in five comprehensive databases (March 2022). The risk of bias was assessed using the Cochrane Collaboration Risk of Bias Tool. RevMan 5.3 was used to perform a meta-analysis on stool consistency, abdominal pain, bloating, quality of life (QoL), fecal Bifidobacterium and Lactobacillus counts, and adverse events. The GRADE approach was used to evaluate the certainty of the evidence. Ten RCTs involving 757 patients were included. Only three studies were rated as having a low risk of bias. The meta-analysis results show that, compared to the placebo, probiotics significantly improved stool consistency (MD = 0.72, 95% CI (0.18, 1.26), p < 0.05, low quality) and increased the number of fecal Bifidobacteria (MD = 1.75, 95% CI (1.51, 2.00), p < 0.05, low quality) and Lactobacillus (MD = 1.69, 95% CI (1.48, 1.89), p < 0.05, low quality), while no significant differences were found in abdominal pain scores, bloating scores, QoL scores, or the incidence of adverse events (p > 0.05). The low-to-very low certainty evidence suggests that probiotics might improve the stool consistency of patients with IBS-C and increase the number of Bifidobacteria and Lactobacilli in feces with good safety. However, more high-quality studies with large samples are needed to verify the findings.


Subject(s)
Irritable Bowel Syndrome , Probiotics , Abdominal Pain/etiology , Abdominal Pain/therapy , Bifidobacterium , Constipation/therapy , Flatulence , Humans , Irritable Bowel Syndrome/drug therapy , Irritable Bowel Syndrome/therapy , Lactobacillus , Probiotics/adverse effects , Randomized Controlled Trials as Topic , Treatment Outcome
11.
Angew Chem Int Ed Engl ; 61(34): e202208886, 2022 Aug 22.
Article in English | MEDLINE | ID: mdl-35753999

ABSTRACT

Materials showing synergy of magnetic and dielectric transitions are promising candidates for future molecular devices. The challenge is how to realize synergy between spin and dielectric transitions with responses to external stimuli. Herein, we design a 2D spin crossover (SCO) complex, [FeII (dpa)][(pzTp)FeIII (CN)3 ]2 (1) (dpa=1,2-bis(4-pyridyl)ethyne and pzTp=tetrakis(pyrazolyl)borate). The local structural changes about the FeII ion were propagated to the whole crystal through the rigid bridging ligands (dpa), leading to elastic interactions to realize the abrupt SCO and rotational movements of polar apical pyrazolyl rings in the [(pzTp)FeIII (CN)3 ]- units. Dielectric measurements confirmed a substantial dielectric change (Δϵ'=2.3) upon the spin transition. This work provides a rational strategy to couple the spin transition and rotation of polar components, which is crucial for the synergetic switch of magnetism and dielectricity.

12.
Dalton Trans ; 51(22): 8865-8873, 2022 Jun 07.
Article in English | MEDLINE | ID: mdl-35635033

ABSTRACT

Two 3d transition metal mononuclear complexes, [(FeL2)(ClO4)2]2·CH3CN (1) and (CoL2)(ClO4)2·2CH3CN (2), have been prepared from a rigid tetradentate bpybox (L = 6,6'-bis(2,5-dihydrooxazol-4-yl)-2,2'-bipyridine) ligand. Single crystal X-ray diffraction analyses together with the help of calculations show that both compounds are octa-coordinate. Direct current magnetic studies reveal their significant magnetic anisotropy. Impressively, field-induced relaxation of magnetism is observed in the two complexes and the apparent anisotropy barriers are 14.1 K for 1 and 21.6 K for 2, respectively. Theoretical calculations reveal that two Fe(II) centers in 1 have small negative D values of -4.897 and -4.825 cm-1 and relatively small E values of 0.646 and 0.830 cm-1, indicating a uniaxial magnetic anisotropy. In contrast, the D and E values in the Co(II) center of 2 are 46.42 cm-1 and 11.51 cm-1, featuring a rhombic anisotropy. This work demonstrates that field-induced slow magnetic relaxation in 3d transition metal complexes with high coordination numbers can be manipulated through rigid ligand design.

13.
Inorg Chem ; 61(15): 5855-5860, 2022 Apr 18.
Article in English | MEDLINE | ID: mdl-35377631

ABSTRACT

The incorporation of two different cyanide building blocks of [(TpR)FeIII(CN)3]- and [AuI(CN)2]- into one molecule afforded a novel hexanuclear [FeIII2FeII2AuI2] complex (1·2Et2O), in which the cyanide-bridged [FeIII2FeII2] square was further grafted by two [AuI(CN)2]- fragments as long arms in syn orientations. Complex 1·2Et2O undergoes a gradual spin crossover (SCO) ffrom low-spin (LS) to high-spin (HS) state for the Fe(II) centers upon desolvation. Remarkably, its desolvated phase (1) exhibits a reversible but atypical two-step (sharp-gradual) SCO behavior with considerable hysteresis (21 K). Variable-temperature single-crystal X-ray structural studies reveal that the hysteretic spin transition takes place synchronously with the concerted displacive motions of the molecules, representing another rare example including multistep and hysteretic spin transitions due to the synergetic SCO and structural phase transition.

14.
Angew Chem Int Ed Engl ; 61(11): e202115367, 2022 Mar 07.
Article in English | MEDLINE | ID: mdl-34971479

ABSTRACT

Manipulation of multi-functions in molecular materials is promising for future switching and memory devices, although it is currently difficult. Herein, we assembled the asymmetric {Fe2 Co} unit into a cyanide-bridged mixed-valence chain {[(Tp)Fe(CN)3 ]2 Co(BIT)} ⋅ 2CH3 OH (1) (Tp=hydrotris(pyrazolyl)borate and BIT=3,4-bis-(1H-imidazol-1-yl)thiophene), which showed reversible multi-phase transitions accompanied by photo-switchable single-chain magnet properties and a dielectric anomaly. Variable-temperature X-ray structural studies revealed thermo- and photo-induced selective electron transfer (ET) between the Co and one of the Fe ions. Alternating-current magnetic susceptibility studies revealed that 1 displayed on and off single-chain magnet behavior by alternating 946-nm and 532-nm light irradiation. A substantial anomaly in the dielectric constant was discovered during the electron transfer process, which is uncommon in similar ET complexes. These findings illustrate that 1 provided a new platform for multi-phase transitions and multi-switches adjusted by selective metal-to-metal ET.

15.
Int J Cancer ; 144(12): 3056-3069, 2019 06 15.
Article in English | MEDLINE | ID: mdl-30536754

ABSTRACT

Toll-like receptors (TLRs) play critical roles in host defense after recognition of conserved microbial- and host-derived components, and their dysregulation is a common feature of various inflammation-associated cancers, including gastric cancer (GC). Despite the recent recognition that metabolic reprogramming is a hallmark of cancer, the molecular effectors of altered metabolism during tumorigenesis remain unclear. Here, using bioenergetics function assays on human GC cells, we reveal that ligand-induced activation of TLR2, predominantly through TLR1/2 heterodimer, augments both oxidative phosphorylation (OXPHOS) and glycolysis, with a bias toward glycolytic activity. Notably, DNA microarray-based expression profiling of human cancer cells stimulated with TLR2 ligands demonstrated significant enrichment of gene-sets for oncogenic pathways previously implicated in metabolic regulation, including reactive oxygen species (ROS), p53 and Myc. Moreover, the redox gene encoding the manganese-dependent mitochondrial enzyme, superoxide dismutase (SOD)2, was strongly induced at the mRNA and protein levels by multiple signaling pathways downstream of TLR2, namely JAK-STAT3, JNK MAPK and NF-κB. Furthermore, siRNA-mediated suppression of SOD2 ameliorated the TLR2-induced metabolic shift in human GC cancer cells. Importantly, patient-derived tissue microarrays and bioinformatics interrogation of clinical datasets indicated that upregulated expression of TLR2 and SOD2 were significantly correlated in human GC, and the TLR2-SOD2 axis was associated with multiple clinical parameters of advanced stage disease, including distant metastasis, microvascular invasion and stage, as well as poor survival. Collectively, our findings reveal a novel TLR2-SOD2 axis as a potential biomarker for therapy and prognosis in cancer.


Subject(s)
Stomach Neoplasms/metabolism , Superoxide Dismutase/metabolism , Toll-Like Receptor 2/metabolism , Biomarkers, Tumor/metabolism , Cell Line, Tumor , Cellular Reprogramming/physiology , Energy Metabolism , Enzyme Induction , Glycolysis , Humans , Immunohistochemistry , Oxidative Phosphorylation , Reactive Oxygen Species/metabolism , Signal Transduction , Stomach Neoplasms/pathology , Tissue Array Analysis , Up-Regulation
16.
Dalton Trans ; 46(2): 524-528, 2017 Jan 03.
Article in English | MEDLINE | ID: mdl-27966730

ABSTRACT

A novel macrocyclic zirconocene(iv) aromatic selenite [(CpZr)8L16]·2(Cp4Zr2(µ-O)Cl2) (complex 1) (Cp = cyclopentadienyl anion; L = 4-fluorobenzeneseleninic acid) was prepared by the reaction of bis(cyclopentadienyl)zirconium dichloride with 4-fluorobenzeneseleninic acid and characterized by elemental analysis, infrared spectroscopy, 1H, 13C NMR spectroscopy, ESI-MS, XRD and X-ray diffraction. The structure analysis shows that complex 1 is a centrosymmetric 32-membered macrocycle containing an eight-nuclear zirconocene. In this complex, the 4-fluorobenzeneseleninic acid ligands adopt bidentate mode in coordinating to zirconium, which play a bridging role in the formation of a macrocycle. The title compound is a rare example of aromatic selenic acid-based zirconocene derivatives. Furthermore, the preliminary in vitro anti-tumor activity of complex 1 has also been studied toward breast cancer cell lines (MDA-MB-231) and human cervix cell lines (HeLa). The results indicate that complex 1 shows higher activity compared with the ligand and bis(cyclopentadienyl)zirconium dichloride.

17.
Sci Transl Med ; 3(77): 77ra30, 2011 Apr 06.
Article in English | MEDLINE | ID: mdl-21471434

ABSTRACT

Fusion genes are chimeric genes formed in cancers through genomic aberrations such as translocations, amplifications, and rearrangements. To identify fusion genes in gastric cancer, we analyzed regions of chromosomal imbalance in a cohort of 106 primary gastric cancers and 27 cell lines derived from gastric cancers. Multiple samples exhibited genomic breakpoints in the 5' region of SLC1A2/EAAT2, a gene encoding a glutamate transporter. Analysis of a breakpoint-positive SNU16 cell line revealed expression of a CD44-SLC1A2 fusion transcript caused by a paracentric chromosomal inversion, which was predicted to produce a truncated but functional SLC1A2 protein. In primary tumors, CD44-SLC1A2 gene fusions were detected in 1 to 2% of gastric cancers, but not in adjacent matched normal gastric tissues. When we specifically silenced CD44-SLC1A2, cellular proliferation, invasion, and anchorage-independent growth were significantly reduced. Conversely, CD44-SLC1A2 overexpression in gastric cells stimulated these pro-oncogenic traits. CD44-SLC1A2 silencing caused significant reductions in intracellular glutamate concentrations and sensitized SNU16 cells to cisplatin, a commonly used chemotherapeutic agent in gastric cancer. We conclude that fusion of the SLC1A2 gene coding region to CD44 regulatory elements likely causes SLC1A2 transcriptional dysregulation, because tumors expressing high SLC1A2 levels also tended to be CD44-SLC1A2-positive. CD44-SLC1A2 may represent a class of gene fusions in cancers that establish a pro-oncogenic metabolic milieu favoring tumor growth and survival.


Subject(s)
Gene Fusion/genetics , Glutamate Plasma Membrane Transport Proteins/genetics , Hyaluronan Receptors/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Stomach Neoplasms/genetics , Stomach Neoplasms/metabolism , Blotting, Western , Cell Line, Tumor , Cell Proliferation , Excitatory Amino Acid Transporter 2 , Gene Expression Regulation, Neoplastic , Humans , In Situ Hybridization, Fluorescence , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured
18.
Clin Cancer Res ; 17(9): 2657-67, 2011 May 01.
Article in English | MEDLINE | ID: mdl-21415212

ABSTRACT

PURPOSE: MicroRNAs (miRNA) play pivotal oncogenic and tumor-suppressor roles in several human cancers. We sought to discover novel tumor-suppressor miRNAs in gastric cancer (GC). EXPERIMENTAL DESIGN: Using Agilent miRNA microarrays, we compared miRNA expression profiles of 40 primary gastric tumors and 40 gastric normal tissues, identifying miRNAs significantly downregulated in gastric tumors. RESULTS: Among the top 80 miRNAs differentially expressed between gastric tumors and normals (false discovery rate < 0.01), we identified hsa-miR-486 (miR-486) as a significantly downregulated miRNA in primary GCs and GC cell lines. Restoration of miR-486 expression in GC cell lines (YCC3, SCH and AGS) caused suppression of several pro-oncogenic traits, whereas conversely inhibiting miR-486 expression in YCC6 GC cells enhanced cellular proliferation. Array-CGH analysis of 106 primary GCs revealed genomic loss of the miR-486 locus in approximately 25% to 30% of GCs, including two tumors with focal genomic losses specifically deleting miR-486, consistent with miR-486 playing a tumor-suppressive role. Bioinformatic analysis identified the secreted antiapoptotic glycoprotein OLFM4 as a potential miR-486 target. Restoring miR-486 expression in GC cells decreased endogenous OLFM4 transcript and protein levels, and also inhibited expression of luciferase reporters containing an OLFM4 3' untranslated region with predicted miR-486 binding sites. Supporting the biological relevance of OLFM4 as a miR-486 target, proliferation in GC cells was also significantly reduced by OLFM4 silencing. CONCLUSIONS: miR-486 may function as a novel tumor-suppressor miRNA in GC. Its antioncogenic activity may involve the direct targeting and inhibition of OLFM4.


Subject(s)
Carcinoma/genetics , Gene Deletion , Granulocyte Colony-Stimulating Factor/genetics , MicroRNAs/physiology , Stomach Neoplasms/genetics , Apoptosis/genetics , Apoptosis Regulatory Proteins/genetics , Apoptosis Regulatory Proteins/metabolism , Carcinoma/pathology , Cell Line, Tumor , Cell Proliferation , Disease Progression , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Genes, Tumor Suppressor , Genomic Instability/genetics , Genomic Instability/physiology , Granulocyte Colony-Stimulating Factor/metabolism , Humans , MicroRNAs/genetics , Microarray Analysis , Neoplasms/genetics , Neoplasms/pathology , Stomach Neoplasms/pathology
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