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Hepatocellular carcinoma (HCC) is one of the deadliest cancers. For patients with advanced HCC, liver function decompensation often occurs, which leads to poor tolerance to chemotherapies and other aggressive treatments. Therefore, it remains critical to develop effective therapeutic strategies for HCC. Etiological factors for HCC are complex and multifaceted, including hepatitis virus infection, alcohol, drug abuse, chronic metabolic abnormalities, and others. Thus, HCC has been categorized as a "genomically unstable" cancer due to the typical manifestation of chromosome breakage and aneuploidy, and oxidative DNA damage. In recent years, immunotherapy has provided a new option for cancer treatments, and the degree of genomic instability positively correlates with immunotherapy efficacies. This article reviews the endogenous and exogenous causes that affect the genomic stability of liver cells; it also updates the current biomarkers and their detection methods for genomic instabilities and relevant applications in cancer immunotherapies. Including genomic instability biomarkers in consideration of cancer treatment options shall increase the patients' well-being.
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The cluster of differentiation 34 (CD34) family, which includes CD34, podocalyxin-like protein 1 (PODXL), and PODXL2, are type-I transmembrane sialomucins and markers of hematopoietic stem cells (HSCs) and vascular-associated tissues. CD34 family proteins are expressed by endothelial cells and hematopoietic precursors. PODXL is well known to be associated with invadopodia formation and to promote the epithelial-mesenchymal transition, tumor migration and invasion. PODXL expression was correlated with poor survival of cancer patients. However, the role of PODXL2 in cancer has been less fully explored. To reveal the novel role of PODXL2 in breast cancer, the present study evaluated PODXL2 levels in relation to clinical outcomes of cancer patients by performing a bioinformatics analysis using the Oncomine database, Kaplan-Meier plots, and the CCLE database. Empirical validation of bioinformatics predictions was conducted utilizing the short hairpin (sh)-RNA silencing method for PODXL2 in the BT474 invasive ductal breast carcinoma cell line. The bioinformatics analysis revealed that PODXL2 overexpression was correlated with poor survival of breast cancer patients, suggesting an oncogenic role of PODXL2 in breast carcinoma. In a validation experiment, knockdown of PODXL2 in BT474 cells slightly influenced cell proliferation, suppressed migration, and inhibited expressions of downstream molecules, including Ras-related C3 botulinum toxin substrate 1 (Rac1), phosphorylated (p)-Akt (S473), and p-paxillin (Y31) proteins. In addition, knockdown of PODXL2 reduced expression levels of cancer stem cell (CSC) markers, including Oct-4 and Nanog, and the breast CSC marker aldehyde dehydrogenase 1 (ALDH1). Collectively, our present study demonstrated that PODXL2 plays a crucial role in cancer development and could serve as a potential prognostic biomarker in breast cancer patients.
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Neoplasias da Mama/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sialoglicoproteínas/metabolismo , Neoplasias da Mama/genética , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Biologia Computacional , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/fisiologia , Feminino , Humanos , Proteínas Proto-Oncogênicas c-akt/genética , Sialoglicoproteínas/genéticaRESUMO
Sinomenine is an alkaloid derived from Sinomenium acutum. Recent studies have found that sinomenine can inhibit various cancers by inhibiting the proliferation, migration and invasion of tumors and inducing apoptosis. This study aims to investigate the effect and mechanism of sinomenine on inhibiting the migration and invasion of human lung adenocarcinoma cells in vitro. The results demonstrate that viabilities of A549 and H1299 cells were inhibited by sinomenine in a dose-dependent manner. When treated with sub-toxic doses of sinomenine, cell migration and invasion are markedly suppressed. Sinomenine decreases the mRNA level of matrix metalloproteinase-2 (MMP-2), MMP-9, and the extracellular inducer of matrix metalloproteinase (EMMPRIN/CD147), but elevates the expression of reversion-inducing cysteine-rich proteins with kazal motifs (RECK) and the tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2. In addition, sinomenine significantly increases the expression of the epithelial marker E-cadherin but concomitantly decreases the expression of the mesenchymal marker vimentin, suggesting that it suppresses epithelial-mesenchymal transition (EMT). Moreover, sinomenine downregulates oncogenic microRNA-21 (miR-21), which has been known to target RECK. The downregulation of miR-21 decreases cell invasion, while the upregulation of miR-21 increases cell invasion. Furthermore, the downregulation of miR-21 stimulates the expression of RECK, TIMP-1/-2, and E-cadherin, but reduces the expression of MMP-2/-9, EMMPRIN/CD147, and vimentin. Taken together, the results reveal that the inhibition of A549 cell invasion by sinomenine may, at least in part, be through the downregulating expression of MMPs and miR-21. These findings demonstrate an attractive therapeutic potential for sinomenine in lung cancer anti-metastatic therapy.
Assuntos
Antineoplásicos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Metaloproteinases da Matriz/genética , MicroRNAs/genética , Morfinanos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/genética , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Inibidor Tecidual de Metaloproteinase-2/genética , Inibidor Tecidual de Metaloproteinase-2/metabolismoRESUMO
The glass transition - an apparent amorphous solidification process - is a central feature of the physical properties of soft materials such as polymers and colloids. A key element of this phenomenon is the observation of a broad spectrum of deviations from an Arrhenius temperature of dynamics in glass-forming liquids, with the extent of deviation quantified by the "fragility" of glass formation. The underlying origin of "fragile" glass formation and its dependence on molecular structure remain major open questions in condensed matter physics and soft materials science. Here we employ molecular dynamics simulations, together with a neural-network-biased genetic algorithm, to design and study model rigid molecules spanning a broad range of fragilities of glass formation. Results indicate that fragility of glass formation can be controlled by tuning molecular asphericity, with extended molecules tending to exhibit low fragilities and compact molecules tending toward higher fragilities. The glass transition temperature itself, on the other hand, correlates well with high-temperature activation behavior and with density. These results point the way towards rational design of glass-forming liquids spanning a range of dynamical behavior, both via these physical insights and via future extensions of this evolutionary design strategy to real chemistries. Finally, we show that results compare well with predictions of the nonlinear Langevin theory of liquid dynamics, which is a precursor of the more recently developed elastically collective nonlinear Langevin equation theory of Mirigian and Schweizer, identifying this framework as a promising basis for molecular design of the glass transition.
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The origin of the precipitous dynamic arrest known as the glass transition is a grand open question of soft condensed matter physics. It has long been suspected that this transition is driven by an onset of particle localization and associated emergence of a glassy modulus. However, progress towards an accepted understanding of glass formation has been impeded by an inability to obtain data sufficient in chemical diversity, relaxation timescales, and spatial and temporal resolution to validate or falsify proposed theories for its physics. Here we first describe a strategy enabling facile high-throughput simulation of glass-forming liquids to nearly unprecedented relaxation times. We then perform simulations of 51 glass-forming liquids, spanning polymers, small organic molecules, inorganics, and metallic glass-formers, with longest relaxation times exceeding one microsecond. Results identify a universal particle-localization transition accompanying glass formation across all classes of glass-forming liquid. The onset temperature of non-Arrhenius dynamics is found to serve as a normalizing condition leading to a master collapse of localization data. This transition exhibits a non-universal relationship with dynamic arrest, suggesting that the nonuniversality of supercooled liquid dynamics enters via the dependence of relaxation times on local cage scale. These results suggest that a universal particle-localization transition may underpin the glass transition, and they emphasize the potential for recent theoretical developments connecting relaxation to localization and emergent elasticity to finally explain the origin of this phenomenon. More broadly, the capacity for high-throughput prediction of glass formation behavior may open the door to computational inverse design of glass-forming materials.
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In this study, we prepared biocompatible superhydrophilic and underwater superoleophobic tannic acid (TA)/polyvinylpyrrolidone (PVP)-coated stainless-steel meshes that mediated extremely efficient separations of mixtures of oil and water. These TA/PVP-coated stainless-steel meshes displayed excellent antifouling properties and could be used to separate oil/water mixtures continuously for up to 24 h. Moreover, a funnel-like TA/PVP-coated stainless-steel mesh device could be used for underwater oil transportation and collection. In conjunction with our continuous oil removal system, this device allowed for the continuous collection and removal of oil pollutants from underwater environments. The high performance of these TA/PVP-coated stainless-steel meshes and their green, low-energy, cost-effective preparation suggests great potential for practical applications.
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Terbufos (S-t-butylthiomethyl-O,O-diethyl phosphorodithioate) is a highly toxic organophosphate which is extensively used as an insecticide and nematicide. Chronic exposure to terbufos causes neuronal injury and predisposes to neurodegenerative diseases. Accumulating evidence has shown that the exposure to terbufos, as an occupational risk factor, may also cause reproductive disorders. However, the exact mechanisms of reproductive toxicity remain unclear. The present study aimed to investigate the toxic effect of terbufos on testicular cells and to explore the mechanism of toxicity on a cellular level. The cytotoxic effects of terbufos on mouse immortalized spermatogonia (GC-1), spermatocytes (GC-2), Leydig (TM3), and Sertoli (TM4) cell lines were assessed by MTT assays, caspase activation, flow cytometry, TUNEL assay, Western blot, and cell cycle analysis. The exposure to different concentrations of terbufos ranging from 50 to 800 µM for 6 h caused significant death in all the used testicular cell lines. Terbufos increased reactive oxygen species (ROS) production, reduced mitochondrial membrane potential, and initiated apoptosis, which was confirmed by a dose-dependent increase in the number of TUNEL-positive apoptotic cells. Blocking ROS production by N-acetyl cysteine (NAC) protected GC-1 cells from terbufos-induced cell death. The results demonstrated that terbufos induces ROS, apoptosis, and DNA damage in testicular cell lines and it should be considered potentially hazardous to testis. Together, this study provided potential molecular mechanisms of terbufos-induced toxicity in testicular cells and suggests a possible protective measure. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1888-1898, 2016.
Assuntos
Antinematódeos/toxicidade , Proteínas Reguladoras de Apoptose/metabolismo , Apoptose/efeitos dos fármacos , Inseticidas/toxicidade , Compostos Organotiofosforados/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Testículo/efeitos dos fármacos , Animais , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Testículo/citologia , Testículo/metabolismoRESUMO
Anoikis resistance allows metastatic tumor cells to survive in a homeless environment. Activation of epithelial growth factor receptor (EGFR) signaling is one of the key mechanisms for metastatic tumor cells to resist anoikis, yet the regulation mechanisms of homeless-triggered EGFR activation in metastatic tumor cells remain unclear. Rhomboid-like-2 (RHBDL2), an evolutionally conserved intramembrane serine protease, can cleave the EGF ligand and thus trigger EGFR activation. Herein, we demonstrated that RHBDL2 overexpression in human epithelial cells resulted in promotion of cell proliferation, reduction of cell adhesion, and suppression of anoikis. During long-term suspension cultures, increased RHBDL2 was only detected in aggressive tumor cell lines. Treatment with the rhomboid protease inhibitor or RHBDL2 shRNA increased cleaved caspase 3, a marker of apoptosis. Finally, inhibition of EGFR activation increased the cleaved caspase 3 and attenuated the detachment-induced focal adhesion kinase phosphorylation. Taken together, these findings provide evidence for the first time that RHBDL2 is a critical molecule in anoikis resistance of malignant epithelial cells, possibly through the EGFR-mediated signaling. Our study demonstrates RHBDL2 as a new therapeutic target for cancer metastasis.
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Anoikis , Receptores ErbB/metabolismo , Proteínas de Membrana/metabolismo , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Epiteliais e Glandulares/patologia , Serina Proteases/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Serina EndopeptidasesRESUMO
Despite the advances in cancer therapy and early detection, breast cancer remains a leading cause of cancer-related deaths among females worldwide. The aim of the current study was to investigate the antitumor activity of a novel compound, 4-(3,4,5-trimethoxyphenoxy)benzoic acid (TMPBA) and its mechanism of action, in breast cancer. Results indicated the relatively high sensitivity of human breast cancer cell-7 and MDA-468 cells towards TMPBA with IC50 values of 5.9 and 7.9 µM, respectively compared to hepatocarcinoma cell line Huh-7, hepatocarcinoma cell line HepG2, and cervical cancer cell line Hela cells. Mechanistically, TMPBA induced apoptotic cell death in MCF-7 cells as indicated by 4',6-diamidino-2-phenylindole (DAPI) nuclear staining, cell cycle analysis and the activation of caspase-3. Western blot analysis revealed the ability of TMPBA to target pathways mediated by mitogen-activated protein (MAP) kinases, 5' adenosine monophosphate-activated protein kinase (AMPK), and p53, of which the concerted action underlined its antitumor efficacy. In addition, TMPBA induced alteration of cyclin proteins' expression and consequently modulated the cell cycle. Taken together, the current study underscores evidence that TMPBA induces apoptosis in breast cancer cells via the modulation of cyclins and p53 expression as well as the modulation of AMPK and mitogen-activated protein kinases (MAPK) signaling. These findings support TMPBA's clinical promise as a potential candidate for breast cancer therapy.
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Antineoplásicos/farmacologia , Benzoatos/farmacologia , Ciclinas/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Éteres Fenílicos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Benzoatos/síntese química , Benzoatos/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células HeLa , Células Hep G2 , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Células MCF-7 , Éteres Fenílicos/síntese química , Éteres Fenílicos/química , Fosforilação/efeitos dos fármacosRESUMO
Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide with poor prognosis due to resistance to conventional chemotherapy and limited efficacy of radiotherapy. Previous studies have noted the induction of endoplasmic reticulum stress or apurinic endonuclease 1 (APE1) expression in many tumors. Therefore, the aim of this study was to investigate the relationship between endoplasmic reticulum (ER stress) and APE1 in hepatocellular carcinoma. Here we investigate the expression of APE1 during ER stress in HepG2 and Huh-7 cell lines. Tunicamycin or brefeldin A, two ER stress inducers, increased APE1 and GRP78, an ER stress marker, expression in HepG2 and Huh-7 cells. Induction of APE1 expression was observed through transcription level in response to ER stress. APE1 nuclear localization during ER stress was determined using immunofluorescence assays in HepG2 cells. Furthermore, expression of Hepatitis B virus pre-S2∆ large mutant surface protein (pre-S2∆), an ER stress-induced protein, also increased GRP78 and APE1 expression in the normal hepatocyte NeHepLxHT cell line. Similarly, tumor samples showed higher expression of APE1 in ER stress-correlated liver cancer tissue in vivo. Our results demonstrate that ER stress and HBV pre-S2∆ increased APE1 expression, which may play an important role in resistance to chemotherapeutic agents or tumor development. Therefore, these data provide an important chemotherapeutic strategy in ER stress and HBV pre-S2∆-associated tumors.
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DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Estresse do Retículo Endoplasmático , Brefeldina A/farmacologia , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico/metabolismo , Células Hep G2 , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/metabolismo , Humanos , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Tunicamicina/farmacologiaRESUMO
α-Solanine, a naturally occurring steroidal glycoalkaloid found in nightshade (Solanum nigrum Linn.), was found to inhibit proliferation and induce apoptosis of tumor cells. However, the mechanism involved in suppression of cancer cell metastasis by α-solanine remains unclear. This study investigates the suppression mechanism of α-solanine on motility of the human prostate cancer cell PC-3. Results show that α-solanine reduces the viability of PC-3 cells. When treated with non-toxic doses of α-solanine, cell invasion is markedly suppressed by α-solanine. α-Solanine also significantly elevates epithelial marker E-cadherin expression, while it concomitantly decreases mesenchymal marker vimentin expression, suggesting it suppresses epithelial-mesenchymal transition (EMT). α-Solanine reduces the mRNA level of matrix metalloproteinase-2 (MMP-2), MMP-9 and extracellular inducer of matrix metalloproteinase (EMMPRIN), but increases the expression of reversion-inducing cysteine-rich protein with kazal motifs (RECK), and tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2. Immunoblotting assays indicate α-solanine is effective in suppressing the phosphorylation of phosphatidylinositide-3 kinase (PI3K), Akt and ERK. Moreover, α-solanine downregulates oncogenic microRNA-21 (miR-21) and upregulates tumor suppressor miR-138 expression. Taken together, the results suggest that inhibition of PC-3 cell invasion by α-solanine may be, at least in part, through blocking EMT and MMPs expression. α-Solanine also reduces ERK and PI3K/Akt signaling pathways and regulates expression of miR-21 and miR-138. These findings suggest an attractive therapeutic potential of α-solanine for suppressing invasion of prostate cancer cell.
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Transição Epitelial-Mesenquimal/efeitos dos fármacos , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Neoplasias da Próstata/tratamento farmacológico , Solanina/administração & dosagem , Caderinas/biossíntese , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Transdução de Sinais/efeitos dos fármacos , Solanum nigrum/química , Inibidor Tecidual de Metaloproteinase-1/biossíntese , Inibidor Tecidual de Metaloproteinase-2/biossínteseRESUMO
Meroterpenoids are a class of fungal natural products that are produced from polyketide and terpenoid precursors. An understanding of meroterpenoid biosynthesis at the genetic level should facilitate engineering of second-generation molecules and increasing production of first-generation compounds. The filamentous fungus Aspergillus nidulans has previously been found to produce two meroterpenoids, austinol and dehydroaustinol. Using targeted deletions that we created, we have determined that, surprisingly, two separate gene clusters are required for meroterpenoid biosynthesis. One is a cluster of four genes including a polyketide synthase gene, ausA. The second is a cluster of 10 additional genes including a prenyltransferase gene, ausN, located on a separate chromosome. Chemical analysis of mutant extracts enabled us to isolate 3,5-dimethylorsellinic acid and 10 additional meroterpenoids that are either intermediates or shunt products from the biosynthetic pathway. Six of them were identified as novel meroterpenoids in this study. Our data, in aggregate, allow us to propose a complete biosynthetic pathway for the A. nidulans meroterpenoids.
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Aspergillus nidulans/metabolismo , Genes Fúngicos , Família Multigênica , Terpenos/metabolismo , Aspergillus nidulans/genética , Biocatálise , Cromatografia Líquida de Alta Pressão , Dimetilaliltranstransferase/metabolismo , Deleção de Genes , Mutação , Fases de Leitura AbertaRESUMO
UNLABELLED: Accumulating evidence suggests the therapeutic potential of the immunosuppressive agent FTY720 (fingolimod) in hepatocellular carcinoma (HCC). Based on our previous finding that FTY720 mediates apoptosis in HCC cells by activating reactive oxygen species (ROS)-protein kinase Cδ (PKCδ) signaling independent of effects on sphingosine-1-phosphate (S1P) receptors, we embarked on the pharmacological exploitation of FTY720 to develop a nonimmunosuppressive analogue with antitumor activity. This effort led to the development of OSU-2S, which exhibits higher potency than FTY720 in suppressing HCC cell growth through PKCδ activation. In contrast to FTY720, OSU-2S was not phosphorylated by sphingosine kinase 2 (SphK2) in vitro, and did not cause S1P1 receptor internalization in HCC cells or T lymphocyte homing in immunocompetent mice. Although devoid of S1P1 receptor activity, OSU-2S exhibited higher in vitro antiproliferative efficacy relative to FTY720 against HCC cells without cytotoxicity in normal hepatocytes. Several lines of pharmacological and molecular genetic evidence indicate that ROS-PKCδ-caspase-3 signaling underlies OSU-2S-mediated antitumor effects, and that differences in the antitumor activity between FTY720 and OSU-2S were attributable to SphK2-mediated phosphorylation of FTY720, which represents a metabolic inactivation of its antitumor activity. Finally, OSU-2S exhibited high in vivo potency in suppressing xenograft tumor growth in both ectopic and orthotopic models without overt toxicity. CONCLUSION: Using the molecular platform of FTY720, we developed OSU-2S, a novel PKCδ-targeted antitumor agent, which is devoid of S1P1 receptor activity and is highly effective in suppressing HCC tumor growth in vivo. These findings suggest that OSU-2S has clinical value in therapeutic strategies for HCC and warrants continued investigation in this regard.
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Antineoplásicos/farmacologia , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/patologia , Propilenoglicóis/farmacologia , Esfingosina/análogos & derivados , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/fisiopatologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Cloridrato de Fingolimode , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/fisiopatologia , Camundongos , Camundongos Nus , Proteína Quinase C-delta/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Esfingosina/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The endoplasmic reticulum (ER) is essential for lipid biosynthesis, and stress signals in this organelle are thought to alter lipid metabolism. Elucidating the mechanisms that underlie the dysregulation of lipid metabolism in hepatocytes may lead to novel therapeutic approaches for the treatment of lipid accumulation. We first tested the effects of several inhibitors on lipid dysregulation induced by tunicamycin, an ER stress inducer. Triacsin C, an inhibitor of long-chain acyl-CoA synthetase (ACSL) 1, 3, and 4, was the most potent among these inhibitors. We then analyzed the expression of the ACSL family during ER stress. The expression of ACSL3 was induced by ER stress in HuH-7 cells and in mice livers. ACSL3 shRNA, but not ACSL1 shRNA, inhibited the induction of lipid accumulation. GSK-3ß inhibitors attenuated ACSL3 expression and the lipid accumulation induced by ER stress in HuH-7 cells. shRNA that target GSK-3ß also inhibited the upregulation of ACSL3 and lipid accumulation in HuH-7 and HepG2 cells. The hepatitis B virus mutant large surface protein, which is known to induce ER stress, increased the lipid content of cells. Similarly, Triacsin C, and GSK-3ß inhibitors abrogated the lipid dysregulation caused by the hepatitis B virus mutant large surface protein. Altogether, ACSL3 and GSK-3ß represent novel therapeutic targets for lipid dysregulation by ER stress.
Assuntos
Coenzima A Ligases/metabolismo , Retículo Endoplasmático/fisiologia , Quinase 3 da Glicogênio Sintase/metabolismo , Hepatócitos/metabolismo , Lipídeos/biossíntese , Fígado/metabolismo , Animais , Linhagem Celular Tumoral , Chaperona BiP do Retículo Endoplasmático , Inibidores Enzimáticos/farmacologia , Glicogênio Sintase Quinase 3 beta , Proteínas de Choque Térmico/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Interferência de RNA , Estresse Fisiológico , Triazenos/farmacologia , Tunicamicina/farmacologia , Regulação para CimaRESUMO
Xanthones are a class of molecules that bind to a number of drug targets and possess a myriad of biological properties. An understanding of xanthone biosynthesis at the genetic level should facilitate engineering of second-generation molecules and increasing production of first-generation compounds. The filamentous fungus Aspergillus nidulans has been found to produce two prenylated xanthones, shamixanthone and emericellin, and we report the discovery of two more, variecoxanthone A and epishamixanthone. Using targeted deletions that we created, we determined that a cluster of 10 genes including a polyketide synthase gene, mdpG, is required for prenyl xanthone biosynthesis. mdpG was shown to be required for the synthesis of the anthraquinone emodin, monodictyphenone, and related compounds, and our data indicate that emodin and monodictyphenone are precursors of prenyl xanthones. Isolation of intermediate compounds from the deletion strains provided valuable clues as to the biosynthetic pathway, but no genes accounting for the prenylations were located within the cluster. To find the genes responsible for prenylation, we identified and deleted seven putative prenyltransferases in the A. nidulans genome. We found that two prenyltransferase genes, distant from the cluster, were necessary for prenyl xanthone synthesis. These genes belong to the fungal indole prenyltransferase family that had previously been shown to be responsible for the prenylation of amino acid derivatives. In addition, another prenyl xanthone biosynthesis gene is proximal to one of the prenyltransferase genes. Our data, in aggregate, allow us to propose a complete biosynthetic pathway for the A. nidulans xanthones.
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Aspergillus nidulans/metabolismo , Genoma Fúngico , Deleção de Sequência , Xantonas/metabolismo , Aspergillus nidulans/genética , Cromatografia Líquida de Alta Pressão , Prenilação de Proteína , Espectrofotometria UltravioletaRESUMO
One-dimensional nanostructures containing heterojunctions by conjugated polymers, such as nanowires, are expected to greatly facilitate efficient charge transfer in bulk-heterojunction (BHJ) solar cells. Thus, a combined theoretical and experimental approach is pursued to explore spontaneous nanowire formation. A dissipative particle dynamics simulation is first performed to study the morphologies formed by rodlike polymers with various side-chain structures. The results surprisingly predict that conjugated polymers with branched side chains are well suited to form thermodynamically stable nanowires. Proof of this concept is provided via the design and synthesis of a branched polymer of regioregular poly(3-2-methylbutylthiophene) (P3MBT), which successfully demonstrates highly dense nanowire formation free from any stringent conditions and stratagies. In BHJ solar cells fabricated using a blend of P3MBT and [6,6]-phenyl-C71-butyric acid methyl ester (PC(71) BM), P3MBT polymers are self-organized into highly crystalline nanowires with a d(100) spacing of 13.30 Å. The hole mobility of the P3MBT:PC(71) BM (1:0.5 by weight) blend film reaches 3.83 × 10(-4) cm(2) V(-1) s(-1) , and the maximum incident photon-to-current efficiency reaches 68%. The results unambiguously prove the spontaneous formation of nanowires using solution-processable conjugated polymers with branched alkyl side chains in BHJ solar cells.
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Nanofios/química , Energia Solar , Tiofenos/química , Absorção , Eletricidade , Microscopia de Força Atômica , Nanofios/ultraestrutura , Polímeros/química , Análise Espectral , Termodinâmica , Difração de Raios XRESUMO
A metabolite isolated from fermented soybean, 8-hydroxydaidzein (8-OHD, 7,8,4'-trihydroxyisoflavone, NSC-678112), is widely used in ethnopharmacological research due to its anti-proliferative and anti-inflammatory effects. We reported previously that 8-OHD provoked reactive oxygen species (ROS) overproduction, and induced autophagy, apoptosis, breakpoint cluster region-Abelson murine leukemia viral oncogene (BCR-ABL) degradation, and differentiation in K562 human chronic myeloid leukemia (CML) cells. However, how 8-OHD regulates metabolism, the extracellular matrix during invasion and metastasis, and survival signaling pathways in CML remains largely unexplored. High-throughput technologies have been widely used to discover the therapeutic targets and pathways of drugs. Bioinformatics analysis of 8-OHD-downregulated differentially expressed genes (DEGs) revealed that Janus kinase/signal transducer and activator of transcription (JAK/STAT), matrix metalloproteinases (MMPs), c-Myc, phosphoinositide 3-kinase (PI3K)/AKT, and oxidative phosphorylation (OXPHOS) metabolic pathways were significantly altered by 8-OHD treatment. Western blot analyses validated that 8-OHD significantly downregulated cytosolic JAK2 and the expression and phosphorylation of STAT3 dose- and time-dependently in K562 cells. Zymography and transwell assays also confirmed that K562-secreted MMP9 and invasion activities were dose-dependently inhibited by 8-OHD after 24 h of treatment. RT-qPCR analyses verified that 8-OHD repressed metastasis and OXPHOS-related genes. In combination with DisGeNET, it was found that 8-OHD's downregulation of PI3K/AKT is crucial for controlling CML development. A STRING protein-protein interaction analysis further revealed that AKT and MYC are hub proteins for cancer progression. Western blotting revealed that AKT phosphorylation and nuclear MYC expression were significantly inhibited by 8-OHD. Collectively, this systematic investigation revealed that 8-OHD exerts anti-CML effects by downregulating JAK/STAT, PI3K/AKT, MMP, and OXPHOS pathways, and MYC expression. These results could shed new light on the development of 8-OHD for CML therapy.
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BACKGROUND: Sperm growth and maturation are correlated with the expression levels of Leucine-rich repeat and WD repeat-containing protein 1 (LRWD1), a widely expressed protein in the human testicles. The decrease in LRWD1 cellular level was linked to the reduction in cell growth and mitosis and the rise in cell microtubule atrophy rates. Since DNA methylation has a major regulatory role in gene expression, this study aimed at exploring the effect of the modulation of DNA methylation on LRWD1 expression levels. RESULTS: The results revealed the presence of a CpG island up of 298 bps (- 253 ~ + 45) upon LRWD1 promoter in NT2/D1 cells. The hypermethylation of the LRWD1 promoter was linked to a reduction in the transcription activity in NT2/D1 cells, as indicated by luciferase reporter assay. The methylation activator, floxuridine, confirmed the decrease in the LRWD1 promoter transcriptional activity. On the other hand, 5-Aza-2'-deoxycytidine (5-Aza-dc, methylation inhibitor), significantly augmented LRWD1 promoter activity and the expression levels of mRNA and proteins. Furthermore, DNA methylation status of LRWD1 promoter in human sperm genomic DNA samples was analyzed. The results indicated that methylation of LRWD1 promoter was correlated to sperm activity. CONCLUSIONS: Thus, the regulation of LRWD1 expression is correlated with the methylation status of LRWD1 promoter, which played a significant role in the modulation of spermatogenesis, sperm motility, and vitality. Based on these results, the methylation status of LRWD1 promoter may serve as a novel molecular diagnostic marker or a therapeutic target in males' infertility.
RéSUMé: CONTEXTE: La croissance et la maturation des spermatozoïdes sont corrélées avec les niveaux d'expression de la protéine 1 riche en répétitions Leucine et contenant des répétitions WD (LRWD1), une protéine largement exprimée dans les testicules humains. La diminution du niveau cellulaire en LRWD1 a été liée à une réduction de la croissance et des mitoses cellulaires, et à une augmentation des taux d'atrophie des microtubules cellulaires. Puisque la méthylation de l'ADN joue un rôle régulateur majeur dans l'expression des gènes, cette étude visait à explorer l'effet de la modulation de la méthylation de l'ADN sur les niveaux d'expression de LRWD1. RéSULTATS: Les résultats ont révélé la présence d'un îlot CpP de 298 pbs (-253~+45) sur le promoteur de LRWD1dans les cellules NT2/D1. L'hyperméthylation du promoteur de LRWD1 était liée à une réduction de l'activité de transcription dans les cellules NT2/D1, comme indiqué par l'analyse de l'expression d'un gène rapporteur codant pour la luciférase. L'activateur de méthylation, la floxuridine, a confirmé la diminution de l'activité transcriptionnelle du promoteur de LRWD1. D'autre part, la 5-Aza-2'-déoxycytidine (5-Aza-dc, inhibiteur de méthylation), a significativement augmenté l'activité du promoteur de LRWD1 et les niveaux d'expression de l'ARNm et des protéines. En outre, le statut de méthylation de l'ADN du promoteur de LRWD1 dans les échantillons d'ADN génomique de sperme humain a été analysé. Les résultats ont indiqué que la méthylation du promoteur de LRWD1 était corrélée à l'activité des spermatozoïdes. CONCLUSIONS: Ainsi, la régulation de l'expression LRWD1 est corrélée avec le statut de méthylation du promoteur de LRWD1, qui a joué un rôle important dans la modulation de la spermatogenèse, de la mobilité et de la vitalité des spermatozoïdes. Sur la base de ces résultats, le statut de méthylation du promoteur de LRWD1 peut servir de nouveau marqueur diagnostic moléculaire ou de cible thérapeutique dans l'infertilité masculine.
RESUMO
BACKGROUND: Pathogenic coronaviruses include Middle East respiratory syndrome coronavirus (MERS-CoV), severe acute respiratory syndrome coronavirus (SARS-CoV), and SARS-CoV-2. These viruses have induced outbreaks worldwide, and there are currently no effective medications against them. Therefore, there is an urgent need to develop potential drugs against coronaviruses. METHODS: High-throughput technology is widely used to explore differences in messenger (m)RNA and micro (mi)RNA expression profiles, especially to investigate protein-protein interactions and search for new therapeutic compounds. We integrated miRNA and mRNA expression profiles in MERS-CoV-infected cells and compared them to mock-infected controls from public databases. RESULTS: Through the bioinformatics analysis, there were 251 upregulated genes and eight highly differentiated miRNAs that overlapped in the two datasets. External validation verified that these genes had high expression in MERS-CoV-infected cells, including RC3H1, NF-κB, CD69, TNFAIP3, LEAP-2, DUSP10, CREB5, CXCL2, etc. We revealed that immune, olfactory or sensory system-related, and signal-transduction networks were discovered from upregulated mRNAs in MERS-CoV-infected cells. In total, 115 genes were predicted to be related to miRNAs, with the intersection of upregulated mRNAs and miRNA-targeting prediction genes such as TCF4, NR3C1, and POU2F2. Through the Connectivity Map (CMap) platform, we suggested potential compounds to use against MERS-CoV infection, including diethylcarbamazine, harpagoside, bumetanide, enalapril, and valproic acid. CONCLUSIONS: The present study illustrates the crucial roles of miRNA-mRNA interacting networks in MERS-CoV-infected cells. The genes we identified are potential targets for treating MERS-CoV infection; however, these could possibly be extended to other coronavirus infections.
Assuntos
Adenocarcinoma de Pulmão/virologia , Infecções por Coronavirus , Células Epiteliais/virologia , Neoplasias Pulmonares/virologia , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas Sanguíneas/metabolismo , COVID-19 , Quimiocina CXCL2/genética , Quimiocina CXCL2/metabolismo , Proteína A de Ligação a Elemento de Resposta do AMP Cíclico/genética , Proteína A de Ligação a Elemento de Resposta do AMP Cíclico/metabolismo , Surtos de Doenças , Fosfatases de Especificidade Dupla/genética , Fosfatases de Especificidade Dupla/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Fosfatases da Proteína Quinase Ativada por Mitógeno/genética , Fosfatases da Proteína Quinase Ativada por Mitógeno/metabolismo , Domínios e Motivos de Interação entre Proteínas , SARS-CoV-2 , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismoRESUMO
ABSTRACT: Severe acute respiratory syndrome coronavirus (SARS-CoV)-2 induces severe infection, and it is responsible for a worldwide disease outbreak starting in late 2019. Currently, there are no effective medications against coronavirus. In the present study, we utilized a holistic bioinformatics approach to study gene signatures of SARS-CoV- and SARS-CoV-2-infected Calu-3 lung adenocarcinoma cells. Through the Gene Ontology platform, we determined that several cytokine genes were up-regulated after SARS-CoV-2 infection, including TNF, IL6, CSF2, IFNL1, IL-17C, CXCL10, and CXCL11. Differentially regulated pathways were detected by the Kyoto Encyclopedia of Genes and Genomes, gene ontology, and Hallmark platform, including chemokines, cytokines, cytokine receptors, cytokine metabolism, inflammation, immune responses, and cellular responses to the virus. A Venn diagram was utilized to illustrate common overlapping genes from SARS-CoV- and SARS-CoV-2-infected datasets. An Ingenuity pathway analysis discovered an enrichment of tumor necrosis factor- (TNF-) and interleukin (IL)-17-related signaling in a gene set enrichment analysis. Downstream networks were predicted by the Database for Annotation, Visualization, and Integrated Discovery platform also revealed that TNF and TNF receptor 2 signaling elicited leukocyte recruitment, activation, and survival of host cells after coronavirus infection. Our discovery provides essential evidence for transcript regulation and downstream signaling of SARS-CoV and SARS-CoV-2 infection.