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2.
Phys Rev Lett ; 131(20): 202502, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38039451

RESUMO

Traditional photonuclear reactions primarily excite giant dipole resonances, making the measurement of isovector giant resonances with higher multipolarities a great challenge. In this Letter, the manipulation of collective excitations of different multipole transitions in even-even nuclei via vortex γ photons is investigated. We develop the calculation method for photonuclear cross sections induced by the vortex γ photon beam using the fully self-consistent random-phase approximation plus particle-vibration coupling (RPA+PVC) model based on Skyrme density functional. We find that the electromagnetic transitions with multipolarity J<|m_{γ}| are forbidden for vortex γ photons due to the angular momentum conservation, with m_{γ} being the projection of total angular momentum of γ photon on its propagation direction. For instance, this allows for probing the isovector giant quadrupole resonance without interference from dipole transitions using vortex γ photons with m_{γ}=2. Furthermore, the electromagnetic transition with J=|m_{γ}|+1 vanishes at a specific polar angle. Therefore, the giant resonances with specific multipolarity can be extracted via vortex γ photons. Moreover, the vortex properties of γ photons can be meticulously diagnosed by measuring the nuclear photon-absorption cross section. Our method opens new avenues for photonuclear excitations, generation of coherent γ photon laser and precise detection of vortex particles, and consequently, has significant impact on nuclear physics, nuclear astrophysics and strong laser physics.

3.
Cancers (Basel) ; 15(20)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37894450

RESUMO

BACKGROUND: The microtubule protein inhibitor C118P shows excellent anti-breast cancer effects. However, the potential targets and mechanisms of C118P in breast cancer remain unknown. METHODS: Real-time cellular analysis (RTCA) was used to detect cell viability. Apoptosis and the cell cycle were detected by flow cytometry. Computer docking simulations, surface plasmon resonance (SPR) technology, and microscale thermophoresis (MST) were conducted to study the interaction between C118P and alanine-serine-cysteine transporter 2 (ASCT2). Seahorse XF technology was used to measure the basal oxygen consumption rate (OCR). The effect of C118P in the adipose microenvironment was explored using a co-culture model of adipocytes and breast cancer cells and mouse cytokine chip. RESULTS: C118P inhibited proliferation, potentiated apoptosis, and induced G2/M cell cycle arrest in breast cancer cells. Notably, ASCT2 was validated as a C118P target through reverse docking, SPR, and MST. C118P suppressed glutamine metabolism and mediated autophagy via ASCT2. Similar results were obtained in the adipocyte-breast cancer microenvironment. Adipose-derived interleukin-6 (IL-6) promoted the proliferation of breast cancer cells by enhancing glutamine metabolism via ASCT2. C118P inhibited the upregulation of ASCT2 by inhibiting the effect of IL-6 in co-cultures. CONCLUSION: C118P exerts an antitumour effect against breast cancer via the glutamine transporter ASCT2.

4.
Science ; 378(6617): 308-313, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36264816

RESUMO

High-performance pervaporation membranes have potential in industrial separation applications, but overcoming the permeability-selectivity trade-off is a challenge. We report a strategy to create highly flexible metal-organic framework nanosheet (MOF-NS) membranes with a faveolate structure on polymer substrates for alcohol-water separation. The controlled growth followed by a surface-coating method effectively produced flexible and defect-free superhydrophobic MOF-NS membranes. The reversible deformation of the flexible MOF-NS and the vertical interlamellar pathways were captured with electron microscopy. Molecular simulations confirmed the structure and revealed transport mechanism. The ultrafast transport channels in MOF-NS exhibited an ultrahigh flux and a separation factor of 8.9 in the pervaporation of 5 weight % ethanol-water at 40°C, which can be used for biofuel recovery. MOF-NS and polydimethylsiloxane synergistically contribute to the separation performance.

5.
Acta Pharmacol Sin ; 43(10): 2651-2665, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35217814

RESUMO

Canagliflozin is an antidiabetic medicine that inhibits sodium-glucose cotransporter 2 (SGLT2) in proximal tubules. Recently, it was reported to have several noncanonical effects other than SGLT2 inhibiting. However, the effects of canagliflozin on skeletal muscle regeneration remain largely unexplored. Thus, in vivo muscle contractile properties recovery in mice ischemic lower limbs following gliflozins treatment was evaluated. The C2C12 myoblast differentiation after gliflozins treatment was also assessed in vitro. As a result, both in vivo and in vitro data indicate that canagliflozin impairs intrinsic myogenic regeneration, thus hindering ischemic limb muscle contractile properties, fatigue resistance recovery, and tissue regeneration. Mitochondrial structure and activity are both disrupted by canagliflozin in myoblasts. Single-cell RNA sequencing of ischemic tibialis anterior reveals a decrease in leucyl-tRNA synthetase 2 (LARS2) in muscle stem cells attributable to canagliflozin. Further investigation explicates the noncanonical function of LARS2, which plays pivotal roles in regulating myoblast differentiation and muscle regeneration by affecting mitochondrial structure and activity. Enhanced expression of LARS2 restores the differentiation of canagliflozin-treated myoblasts, and accelerates ischemic skeletal muscle regeneration in canagliflozin-treated mice. Our data suggest that canagliflozin directly impairs ischemic skeletal muscle recovery in mice by downregulating LARS2 expression in muscle stem cells, and that LARS2 may be a promising therapeutic target for injured skeletal muscle regeneration.


Assuntos
Aminoacil-tRNA Sintetases , Inibidores do Transportador 2 de Sódio-Glicose , Aminoacil-tRNA Sintetases/metabolismo , Aminoacil-tRNA Sintetases/farmacologia , Animais , Canagliflozina/metabolismo , Canagliflozina/farmacologia , Canagliflozina/uso terapêutico , Diferenciação Celular , Glucose/metabolismo , Hipoglicemiantes/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Isquemia/tratamento farmacológico , Isquemia/metabolismo , Camundongos , Músculo Esquelético/metabolismo , Sódio/metabolismo , Sódio/farmacologia , Transportador 2 de Glucose-Sódio/metabolismo , Transportador 2 de Glucose-Sódio/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia
6.
Psychol Health Med ; 27(9): 1877-1883, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33715523

RESUMO

The pandemic of Coronavirus Disease 2019(COVID-19) could be sources of anxiety among pregnant women and health care workers, which might affect the decision making on the mode of delivery. The aim of this study was to explore whether the cesarean section rates had significantly increased after the outbreak of COVID-19. We analyzed the labor data with cesarean rates in a tertiary maternity center during COVID-19 epidemic months from January to March in 2020, compared with pre-epidemic parallel months in 2019 by using Z-score test for proportions. Even though none of the staff or patient suffered with COVID-19 in the hospital, we found the cesarean section rates slightly increased in a non-infected population after the outbreak of COVID-19. Obstetricians should beware of the possible effects of COVID-19 on the mode of delivery.


Assuntos
COVID-19 , Trabalho de Parto , COVID-19/epidemiologia , Cesárea , Estudos Transversais , Feminino , Humanos , Pandemias , Gravidez
7.
Front Public Health ; 9: 699821, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34568255

RESUMO

This paper aims to determine the existence of convergence in health expenditures among Association for South East Asian Nations (ASEAN) countries. Based on the SPSM procedure and panel KSS unit root test results, the public health expenditures (PUHE) in Indonesia, Lao PDR, Cambodia, the Philippines, and Myanmar are converging, while that of Brunei Darussalam, Malaysia, Vietnam, Singapore, and Thailand are diverging. In addition, the sequences of private health expenditures (PRHE) in ASEAN member states are stationary, which implies convergence. This finding is in accordance with Wagner's law, that is, as nations develop, they are forced to expand public expenditure. Specifically, countries with low levels of PUHE tend to catch up with the high health spending countries. This research has policy implications with regard to the convergence of health expenditure across countries. The government in low- and lower-middle income countries should raise PUHE to provide access to health services for those who are unaffordable individuals.


Assuntos
Gastos em Saúde , Sudeste Asiático/epidemiologia , Humanos , Indonésia/epidemiologia , Filipinas , Tailândia
8.
J Clin Lipidol ; 15(1): 162-172, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33144084

RESUMO

BACKGROUND: Excess maternal triglyceride (mTG) exposure during early or late pregnancy increases risks of adverse pregnancy outcomes. However, it is inconclusive whether persistently high maternal triglyceride during whole pregnancy has more negative associations. OBJECTIVE: To explore whether persistently high maternal triglyceride (mTG) levels from early to late pregnancy further increases the risk of adverse pregnancy outcomes. METHODS: We included 12,715 women who had a singleton birth and who underwent routine serum lipid screenings in both early (9-13 weeks) and late (28-42 weeks) pregnancy during May 2018 to July 2019 in a university-based maternity center. Risks for gestational diabetes mellitus (GDM), preeclampsia, preterm delivery, small/large for gestational age (LGA) were estimated. RESULTS: Elevated mTG levels during early pregnancy were associated with increased risks of preterm delivery (AOR, 1.52; 95% CI, 1.21 to 1.90), preeclampsia (1.75; 1.29 to 2.36), gestational diabetes mellitus (1.95; 1.69 to 2.25), and LGA (1.28; 1.12 to 1.46). Compared with those with low mTG levels both in the 1st and 3rd trimesters, persistently high mTG levels increased the risks of preeclampsia (2.53; 1.66 to 3.84), GDM (1.97; 1.57 to 2.47), and LGA (1.68; 1.37 to 2.07). However, persistently high mTG levels only slightly increased risk of LGA when compared with high mTG levels during the 1st trimester alone (1.34, 1.01 to 1.77). CONCLUSIONS: Elevated mTG levels during early pregnancy not in late pregnancy could be the crucial risk factor associated with adverse pregnancy outcomes. These results suggest the importance of lipid screenings and preventions during early pregnancy, which may help to improve pregnancy outcomes.


Assuntos
Resultado da Gravidez , Adulto , Peso ao Nascer , Feminino , Humanos , Recém-Nascido , Gravidez , Fatores de Risco
9.
Aging (Albany NY) ; 12(19): 19766-19784, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33049717

RESUMO

Accumulating evidence from epidemiological studies of humans and genetic models in rodents has shown that offspring from males of advanced paternal age (APA) are susceptible to metabolic and neurological disorders. However, knowledge of molecular mechanism(s) underlying these metabolic and behavioral changes at the intergeneration and trans-generation levels from APA is limited. Here, we characterized changes on glucose and cholesterol metabolism, and also autism spectrum disorders (ASD)-like behaviors in 1st and 2nd generations from 12- and 18-month-old male mice, respectively. Whole Genome Bisulfite Sequencing (WGBS) of sperm from APA mice identified differentially methylated regions (DMRs) within the whole genome, and DMRs within promoter regions, suggesting that specific genes and relevant pathways might be associated with autism and aberrant glucose metabolism in the offspring from APA males. These results strongly suggest that epigenetic reprogramming induced by aging in male sperm may lead to high risks of aberrant glucose metabolism and the development of ASD behaviors in intergenerational and transgenerational offspring.

10.
Toxicon ; 186: 12-18, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32698025

RESUMO

The T-2 toxin exerts a variety of toxic effects on both experimental animals and humans. The integrin family plays a major role in mediating cell-ECM interactions. Therefore, the present study aimed to investigate the involvement of integrin α2ß1 in T-2 toxin-induced C28/I2 chondrocyte damage. The pathological damage of articular cartilage injury induced by T-2 toxin was observed by H&E staining. The expression levels of collagen 2 and MMP-13 (Matrix metalloproteinases 13) were detected using immunohistochemistry in articular cartilage tissues and western blotting in the cells. The blocking effect of integrin α2ß1 inhibitor on T-2 toxin-induced chondrocyte matrix degradation was examined by western blotting. Further, the effect of integrin α2ß1 inhibitor on T-2 toxin-induced chondrocyte apoptosis was analyzed. About 100 ng/g body weight (BW)/day T-2 toxin was fed to Sprague-Dawley (SD) rats, T-2 toxin treatment (0, 6, 12, and 24 ng/mL) induced C28/I2 chondrocytes. Both in vivo and in vitro, chondrocyte survival was inhibited, and the production of type II collagen was significantly reduced (p < 0.05). However, the level of MMP-13 was up-regulated (p < 0.05). Matrix degradation was effectively blocked after the pre-treatment by integrin α2ß1 inhibitor (p < 0.05). Conclusively, Integrin α2ß1 is a critical signaling pathway for communication between cells and the extracellular matrix, the present study provides a new clue to elucidate the mechanism of T-2 toxin-induced chondrocyte damage.


Assuntos
Colágeno Tipo II/metabolismo , Integrina alfa2beta1/metabolismo , Toxina T-2/toxicidade , Animais , Cartilagem Articular , Colágeno , Humanos , Metaloproteinase 13 da Matriz , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
11.
Arch Gynecol Obstet ; 301(3): 721-727, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32114673

RESUMO

PURPOSE: To investigate whether there are left-right asymmetries in tubal endometriosis and the factors affecting this predisposition. METHODS: Women who underwent salpingectomy for gynecological diseases and were diagnosed with tubal endometriosis between January 2002 and July 2019 were included in the study. The frequencies of left and right tubal endometriosis were compared with the expected 50% using a binominal test. The demographic characteristics and presence of ovarian endometrioid cysts, adenomyosis, and hydrosalpinx were also analyzed. RESULTS: During the study period of more than 17 years, 305 women were diagnosed with tubal endometriosis. The distribution of tubal endometriosis in the left or right fallopian tubes was analyzed. Tubal endometriosis was found in the left fallopian tube in 168 (55.08%) women, in the right fallopian tube in 93 (30.49%), and bilaterally in 44 (14.43%). Left unilateral tubal endometriosis was found most frequently (64.37%, 168/261), and its incidence was significantly higher than 50% (P < 0.001, binominal test). Furthermore, the frequency of left ovarian endometrioid cysts (58.82%) was higher than that of right ovarian endometrioid cysts (41.18%) (P < 0.001, binominal test). CONCLUSION: Our study confirms that tubal endometriosis is a left-side asymmetric disease, and this predisposition is highly consistent with ovarian endometrioid cysts, which supports the transplantation theory of the origin of endometriosis.


Assuntos
Endometriose/diagnóstico , Endometriose/epidemiologia , Adulto , Feminino , Humanos , Estudos Retrospectivos , Adulto Jovem
12.
Biosci Rep ; 40(1)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31904090

RESUMO

Cilia and flagella are critical organelles with conserved internal structures and diverse developmental and physiological processes according to cell type. Although the core components of structures are shared with thousands of associated proteins involved in cilia or flagella formation, we hypothesized that some unknown proteins, such as outer dense fiber 2 (Odf2/Cenexin) perform distinct functions in these organelles. In the present study, we identified several uncharacterized proteins through mass spectrometry interactome analysis of Odf2/Cenexin proteins. We further examined the expression patterns and functions of a protein named cilia and flagella associated protein 58 (Cfap58) in cultured astrocytes and sperm flagella. The results of a combination of biochemical analyses and drug administration studies reveal that Cfap58 is a testis-enrichment protein that exhibits similar localization to Odf2/Cenexin proteins and is required for the elongation of the primary cilium and sperm midpiece via modulation of the Notch signaling pathway. However, the cell cycle-related functions and localization of Odf2/Cenexin in the mother centriole were not altered in Cfap58 knockdown cells. These findings indicate that Cfap58 may be partially recruited by Odf2/Cenexin proteins and is indispensable for the cilia and flagellar assembly. These data provide us with a better understanding of ciliogenesis and flagellar elongation and may aid in identifying new targets for diseases caused by Notch-mediated ciliopathies and flagellar abnormalities.


Assuntos
Astrócitos/metabolismo , Cílios/metabolismo , Flagelos/metabolismo , Receptores Notch/metabolismo , Peça Intermédia do Espermatozoide/metabolismo , Animais , Células HEK293 , Proteínas de Choque Térmico/metabolismo , Humanos , Masculino , Camundongos Endogâmicos C57BL , Transdução de Sinais
13.
Sci Total Environ ; 672: 71-80, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30954826

RESUMO

With the growth of international trade, the geographical separation of production and consumption links of goods has become increasingly common. Commodity-consuming countries can transfer carbon emissions generated in the production of commodities to commodity-producing countries through foreign trade while meeting their domestic consumption demands and emission reduction targets. This issue of embodied carbon emissions in international trade has received wide attention in recent years and has exerted significant impact on the labor income share of developing nations. This study determines the relationship between carbon emission and labor income share in the imports and exports of intermediate products from the perspective of the global value chain. Empirical results show that in developing countries, labor income share has a negative relationship with trade and a positive one with embodied carbon emission. Furthermore, to distinguish the heterogeneity between industries and verify the hypothesis, we classified 57 sectors into 7 main industries based on the method of Meng et al. (2018). Specifically, labor-intensive exports and technology-intensive imports increase labor income share while technology-intensive exports and labor-intensive imports reduce it. In addition to the light industry, the upgrading of women's employment structure can promote the increase of labor income share in host countries. The policy relevance of this study rests on its findings that developing countries can increase their labor income share through imports related to technology-intensive industries and exports related to labor-intensive industries; and that countries worldwide can fundamentally reduce embodied carbon emissions in trade by means of innovations in science and technology to realize sustainable development of the environment, economy, and society.

14.
Phytomedicine ; 57: 117-128, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30668314

RESUMO

BACKGROUND: Topotecan (TPT) is a Topo I inhibitor and shows obvious anti-cancer effects on gastric cancer. Cancer cells reprogram their metabolic pathways to increase nutrients uptake, which has already been a hallmark of cancer. But the effect of TPT on metabolism in gastric cancer remains unknown. PURPOSE: To investigate the effect of TPT on metabolism in gastric cancer. METHODS: ATP production was measured by ATP Assay kit. Glucose and glutamine uptake were measured by Glucose (HK) Assay Kit and Glutamine/Glutamate Determination Kit respectively. To detect glutathione (GSH) concentration and reactive oxygen species (ROS) generation, GSH and GSSG Assay Kit and ROS Assay Kit were adopted. Apoptosis rates, mitochondrial membrane potential (MMP) were determined by flow cytometry and protein levels were analyzed by immumohistochemical staining and western blotting. RESULTS: TPT increased ATP production. TPT promoted glucose uptake possibly via up-regulation of hexokinase 2 (HK2) or glucose transporter 1 (GLUT1) expression, while decreased glutamine uptake by down-regulation of ASCT2 expression. ASCT2 inhibitor GPNA and ASCT2 knockdown significantly suppressed the growth of gastric cancer cells. Inhibition of ASCT2 reduced glutamine uptake which led to decreased production of GSH and increased ROS level. ASCT2 knockdown induced apoptosis via the mitochondrial pathway and weakened anti-cancer effect of TPT. CONCLUSION: TPT inhibits glutamine uptake via down-regulation of ASCT2 which causes oxidative stress and induces apoptosis through the mitochondrial pathway. Moreover, TPT inhibits proliferation partially via ASCT2. These observations reveal a previously undescribed mechanism of ASCT2 regulated gastric cancer proliferation and demonstrate ASCT2 is a potential anti-cancer target of TPT.


Assuntos
Sistema ASC de Transporte de Aminoácidos/metabolismo , Antineoplásicos/farmacologia , Antígenos de Histocompatibilidade Menor/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Neoplasias Gástricas/tratamento farmacológico , Topotecan/farmacologia , Sistema ASC de Transporte de Aminoácidos/genética , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Glutamina/metabolismo , Glutationa/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Antígenos de Histocompatibilidade Menor/genética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Terapia de Alvo Molecular/métodos , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia
15.
Cell Commun Signal ; 16(1): 100, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30563531

RESUMO

BACKGROUND: Adipocytes make up the major component of breast tissue, accounting for 90% of stromal tissue. Thus, the crosstalk between adipocytes and breast cancer cells may play a critical role in cancer progression. Adipocyte-breast cancer interactions have been considered important for the promotion of breast cancer metastasis. However, the specific mechanisms underlying these interactions are unclear. In this study, we investigated the mechanisms of adipocyte-mediated breast cancer metastasis. METHODS: Breast cancer cells were cocultured with mature adipocytes for migration and 3D matrix invasion assays. Next, lentivirus-mediated loss-of-function experiments were used to explore the function of lysyl hydroxylase (PLOD2) in breast cancer migration and adipocyte-dependent migration of breast cancer cells. The role of PLOD2 in breast cancer metastasis was further confirmed using orthotopic mammary fat pad xenografts in vivo. Clinical samples were used to confirm that PLOD2 expression is increased in tumor tissue and is associated with poor prognosis of breast cancer patients. Cells were treated with cytokines and pharmacological inhibitors in order to verify which adipokines were responsible for activation of PLOD2 expression and which signaling pathways were activated in vitro. RESULTS: Gene expression profiling and Western blotting analyses revealed that PLOD2 was upregulated in breast cancer cells following coculture with adipocytes; this process was accompanied by enhanced breast cancer cell migration and invasion. Loss-of-function studies indicated that PLOD2 knockdown suppressed cell migration and disrupted the formation of actin stress fibers in breast cancer cells and abrogated the migration induced by following coculture with adipocytes. Moreover, experiments performed in orthotopic mammary fat pad xenografts showed that PLOD2 knockdown could reduce metastasis to the lung and liver. Further, high PLOD2 expression correlated with poor prognosis of breast cancer patients. Mechanistically, adipocyte-derived interleukin-6 (IL-6) and leptin may facilitate PLOD2 upregulation in breast cancer cells and promote breast cancer metastasis in tail vein metastasis assays. Further investigation revealed that adipocyte-derived IL-6 and leptin promoted PLOD2 expression through activation of the JAK/STAT3 and PI3K/AKT signaling pathways. CONCLUSIONS: Our study reveals that adipocyte-derived IL-6 and leptin promote PLOD2 expression by activating the JAK/STAT3 and PI3K/AKT signaling pathways, thus promoting breast cancer metastasis.


Assuntos
Adipócitos/metabolismo , Neoplasias da Mama/patologia , Interleucina-6/metabolismo , Leptina/metabolismo , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/metabolismo , Regulação para Cima , Células 3T3-L1 , Adipocinas/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Feminino , Técnicas de Silenciamento de Genes , Humanos , Janus Quinases/metabolismo , Camundongos , Metástase Neoplásica , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/deficiência , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/genética , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Microambiente Tumoral
16.
Cell Physiol Biochem ; 45(5): 1975-1985, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29529599

RESUMO

BACKGROUND/AIMS: Long noncoding RNAs (lncRNAs) have recently emerged as novel and potentially promising therapeutic targets in various cancers. However, the expression pattern and biological function of lncRNAs in glioma remain largely elusive. In the present study, we investigated the functional role of an lncRNA, small nucleolar RNA host gene 16 (SNHG16), in glioma. METHODS: The expression levels of SNHG16 and miR-4518 were measured using qRT-PCR. The relationship between the levels of SNHG16 and clinicopathologic features were statically analyzed. The levels of proteins were detected using western blot. Bioinformatics analysis and luciferase reporter assays were applied to the analysis of the relationship between SNHG16, miR-4518 and PRMT5. Cell viability and apoptosis were measured using MTT and apoptosis ELISA assay, respectively. RESULTS: SNHG16 was highly expressed in glioma tissues and cell lines, which was related to poorer clinicopathologic features and shorter survival time. Knockdown of SNHG16 inhibits the viability and induces apoptosis of glioma cells. Further investigation revealed that SNHG16 could up-regulate the expression of miR-4518 targeted gene PRMT5 via acting as an endogenous sponge of miR-4518. Moreover, SNHG16 also affects the expression of Bcl-2 family proteins and the activation of PI3K/Akt signaling pathway. CONCLUSION: Our study revealed a novel SNHG16-miR-4518-PRMT5 pathway regulatory axis in glioma pathogenesis. SNHG16 could be used as a potential therapeutic target in the treatment of glioma.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , MicroRNAs/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , RNA Longo não Codificante/metabolismo , Regiões 3' não Traduzidas , Idoso , Antagomirs/metabolismo , Apoptose , Sequência de Bases , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Linhagem Celular Tumoral , Proliferação de Células , Intervalo Livre de Doença , Feminino , Glioma/genética , Glioma/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/metabolismo , Proteína-Arginina N-Metiltransferases/antagonistas & inibidores , Proteína-Arginina N-Metiltransferases/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Alinhamento de Sequência , Transdução de Sinais , Regulação para Cima
17.
Stem Cells ; 34(5): 1273-83, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26850336

RESUMO

Human mesenchymal stem cells (hMSCs) possess the potential to differentiate into endothelial cells (EC). DNA methylation plays an important role in cell differentiation during development. However, the role of the DNA methyltransferases Dnmt1 and Dnmt3a in specific arterial differentiation of hMSCs is not clear. Here, we show that the CpG islands in the promoter regions of the EC specification and arterial marker genes were highly methylated in hMSCs based on bisulfite genomic sequencing. Treatment with the DNMT inhibitor 5-aza-dc induced the reactivation of EC specification and arterial marker genes by promoting demethylation of these genes as well as stimulating tube-like structure formation. The hMSCs with stable knockdown of Dnmt1/Dnmt3a were highly angiogenic and expressed several arterial specific transcription factors and marker genes. A Matrigel plug assay confirmed that Dnmt1/Dnmt3a stable knockdown hMSCs enhanced blood vessel formation compared with WT MSCs. We also identified that the transcription factor E2F1 could upregulate the transcription of arterial marker genes by binding to the promoters of arterial genes, suggesting its critical role for arterial specification. Moreover, miRNA gain/loss-of-function analyses revealed that miR152 and miR30a were involved in endothelial differentiation of hMSCs by targeting Dnmt1 and Dnmt3a, respectively. Taken together, these data suggest that Dnmt1 and Dnmt3a are critical regulators for epigenetic silencing of EC marker genes and that E2F1 plays an important role in promoting arterial cell determination. Stem Cells 2016;34:1273-1283.


Assuntos
Artérias/citologia , Diferenciação Celular , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , Técnicas de Silenciamento de Genes , Células-Tronco Mesenquimais/citologia , Neovascularização Fisiológica/genética , Especificidade de Órgãos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , DNA Metiltransferase 3A , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/enzimologia , MicroRNAs/genética , MicroRNAs/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/genética
18.
Oncotarget ; 6(28): 25441-51, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26213845

RESUMO

The eukaryotic translation initiation factor 3a (eIF3a) is one of the core subunits of the translation initiation complex eIF3, responsible for ribosomal subunit joining and mRNA recruitment to the ribosome. Our previous study identified that it was correlated with platinum response in lung cancer. The current study aims to test the hypothesis that eIF3a may affect the drug response and prognosis of ovarian cancer patients receiving platinum-based chemotherapy by regulating xeroderma pigmentosum complementation group C (XPC) and p27(Kip1). Immunohistochemistry and western blot was used to determine the expression of eIF3a in 126 human ovarian cancer tissues followed by association analysis of eIF3a expression with patient's response and survival. Ectopic over-expression and RNA interference knockdown of eIF3a were carried out in A2780/cisplatin (DDP) and its parental A2780 cells, respectively, to determine the effect of altered eIF3a expression on cellular response to cisplatin by employing MTT assay. Western Blot analyses were also carried out to determine the regulation of eIF3a on XPC and p27(Kip1). eIF3a expression was associated with response of ovarian cancer patients to DDP-based chemotherapy and their survival. Overexpression and knockdown of eIF3a increased and decreased the cellular response to cisplatin in A2780/DDP and A2780 cells, respectively. In addition, XPC and p27(Kip1) were down regulated by eIF3a. eIF3a improves ovarian cancer patients' response to DDP-based chemotherapy via down regulating XPC and p27(Kip1).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/uso terapêutico , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fator de Iniciação 3 em Eucariotos/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p27/genética , Proteínas de Ligação a DNA/genética , Relação Dose-Resposta a Droga , Fator de Iniciação 3 em Eucariotos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Modelos de Riscos Proporcionais , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção , Resultado do Tratamento
19.
Inorg Chem ; 54(6): 2726-33, 2015 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-25738762

RESUMO

The preparation of chiral 2-(alkylsulfinyl)phenol compounds by enantioselective coordination-oxidation of the thioether ruthenium complexes with a chiral-at-metal strategy has been developed. The enantiomerically pure sulfoxide complexes Δ-[Ru(bpy)2{(R)-LO-R}](PF6) (bpy is 2,2'-bipyridine, HLO-R is 2-(alkylsulfinyl)phenol, R = Me (Δ-1a), Et (Δ-2a), iPr (Δ-3a), Bn (Δ-4a), and Nap (Δ-5a)) and Λ-[Ru(bpy)2{(S)-LO-R}](PF6) (R = Me (Λ-1a), Et (Λ-2a), iPr (Λ-3a), Bn (Λ-4a), and Nap (Λ-5a)) have been synthesized by the reaction of Δ-[Ru(bpy)2(py)2](2+) or Λ-[Ru(bpy)2(py)2](2+) with the prochiral thioether ligands 2-(alkylthio)phenol (HL-R), followed by enantioselective oxidation with m-CPBA as oxidant. The X-ray crystallography was used to verify the stereochemistry of ruthenium complexes and sulfur atoms. The configurations of the ruthenium complexes are stable during the coordination and oxidation reactions. Moreover, the chiral sulfoxide ligands are enantioselectively generated by controlling of the configuration of ruthenium centers in the course of oxidation reaction. That is, the Λ configuration at the ruthenium center generates the S sulfoxide ligand; on the contrary, the Δ configuration of the ruthenium complex originates the R sulfoxide ligand. Acidolysis of Λ-[Ru(bpy)2{(R)-LO-R}](PF6) and Δ-[Ru(bpy)2{(S)-LO-R}](PF6) complexes in the presence of TFA-MeCN afforded the chiral ligands (R)-HLO-R and (S)-HLO-R in 96-99% ee values, respectively. Importantly, the chiral ruthenium complexes can be recycled as Δ/Λ-[Ru(bpy)2(MeCN)2](PF6)2 and reused in a next reaction cycle with complete retention of the configurations at ruthenium centers.


Assuntos
Compostos Organometálicos/química , Rutênio/química , Sulfóxidos/química , Sulfóxidos/síntese química , 2,2'-Dipiridil/química , Ligantes , Modelos Moleculares , Conformação Molecular , Estereoisomerismo
20.
Chem Commun (Camb) ; 50(42): 5644-7, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24733168

RESUMO

The reaction of Δ/Λ-[Ru(bpy)2(py)2](2+) with a prochiral sulfide ligand, and then in situ oxidation, provide the corresponding Δ-[Ru(bpy)2{(R)-OSO-iPr}](+) and Λ-[Ru(bpy)2{(S)-OSO-iPr}](+) (OSO-iPr = 2-isopropylsulfonylbenzonate) enantiomers in a yield of 83% with 98% ee. The chiral sulfoxides were obtained by treatment of the sulfoxide complexes with TFA in a yield of 90% with 88-91% ee.


Assuntos
Complexos de Coordenação/química , Rutênio/química , Sulfóxidos/química , Modelos Moleculares , Conformação Molecular , Estereoisomerismo
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