RESUMO
GGGGCC (G4C2) hexanucleotide repeat expansion (HRE) in the first intron of the chromosome 9 open reading frame 72 (C9ORF72) gene is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Among the five dipeptide repeat proteins translated from G4C2 HRE, arginine-rich poly-PR (proline:arginine) is extremely toxic. However, the molecular mechanism responsible for poly-PR-induced cell toxicity remains incompletely understood. Here, we found that poly-PR overexpression triggers severe DNA damage in cultured cells, primary cortical neurons, and the motor cortex of a poly-PR transgenic mouse model. Interestingly, we identified a linkage between poly-PR and RNA-binding protein fused in sarcoma (FUS), another ALS-related gene product associated with DNA repair. Poly-PR interacts with FUS both in vitro and in vivo, phase separates with FUS in a poly-PR concentration-dependent manner, and impairs the fluidity of FUS droplets in vitro and in cells. Moreover, poly-PR impedes the recruitment of FUS and its downstream protein XRCC1 to DNA damage foci after microirradiation. Importantly, overexpression of FUS significantly decreased the level of DNA damage and dramatically reduced poly-PR-induced cell death. Our data suggest the severe DNA damage caused by poly-PR and highlight the interconnection between poly-PR and FUS, enlightening the potential therapeutic role of FUS in alleviating poly-PR-induced cell toxicity.
Assuntos
Esclerose Lateral Amiotrófica , Demência Frontotemporal , Animais , Camundongos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Expansão das Repetições de DNA , Demência Frontotemporal/genética , Demência Frontotemporal/metabolismo , Proteínas/genética , Dano ao DNA/genética , Arginina/genética , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Dipeptídeos/genéticaRESUMO
Arabidopsis LHP1 (LIKE HETEROCHROMATIN PROTEIN 1), a unique homolog of HP1 in Drosophila, plays important roles in plant development, growth, and architecture. In contrast to specific binding of the HP1 chromodomain to methylated H3K9 histone tails, the chromodomain of LHP1 has been shown to bind to both methylated H3K9 and H3K27 histone tails, and LHP1 carries out its function mainly via its interaction with these two epigenetic marks. However, the molecular mechanism for the recognition of methylated histone H3K9/27 by the LHP1 chromodomain is still unknown. In this study, we characterized the binding ability of LHP1 to histone H3K9 and H3K27 peptides and found that the chromodomain of LHP1 binds to histone H3K9me2/3 and H3K27me2/3 peptides with comparable affinities, although it exhibited no binding or weak binding to unmodified or monomethylated H3K9/K27 peptides. Our crystal structures of the LHP1 chromodomain in peptide-free and peptide-bound forms coupled with mutagenesis studies reveal that the chromodomain of LHP1 bears a slightly different chromodomain architecture and recognizes methylated H3K9 and H3K27 peptides via a hydrophobic clasp, similar to the chromodomains of human Polycomb proteins, which could not be explained only based on primary structure analysis. Our binding and structural studies of the LHP1 chromodomain illuminate a conserved ligand interaction mode between chromodomains of both animals and plants, and shed light on further functional study of the LHP1 protein.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Histonas , Fatores de Transcrição , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Metilação , Peptídeos/químicaRESUMO
The NSD proteins, namely NSD1, NSD2 and NSD3, are lysine methyltransferases, which catalyze mono- and di-methylation of histone H3K36. They are multi-domain proteins, including two PWWP domains (PWWP1 and PWWP2) separated by some other domains. These proteins act as potent oncoproteins and are implicated in various cancers. However the biological functions of these PWWP domains are still largely unknown. To better understand the functions of these proteins' PWWP domains, we cloned, expressed and purified all the PWWP domains of these NSD proteins to characterize their interactions with methylated histone peptides and dsDNA by quantitative binding assays and crystallographic analysis. Our studies indicate that all these PWWP domains except NSD1_PWWP1 bind to trimethylated H3K36, H3K79 peptides and dsDNA weakly. Our crystal structures uncover that the NDS3_PWWP2 and NSD2_PWWP1 domains, which hold an extremely long α-helix and α-helix bundle, respectively, need a conformation adjustment to interact with nucleosome.
Assuntos
DNA/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Proteínas Nucleares/metabolismo , Domínios Proteicos , Proteínas Repressoras/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação/genética , Cristalografia por Raios X , DNA/química , DNA/genética , Histona-Lisina N-Metiltransferase/química , Histona-Lisina N-Metiltransferase/genética , Histonas/química , Humanos , Lisina/química , Lisina/metabolismo , Metilação , Modelos Moleculares , Proteínas Nucleares/química , Proteínas Nucleares/genética , Conformação de Ácido Nucleico , Ligação Proteica , Proteínas Repressoras/química , Proteínas Repressoras/genética , Homologia de Sequência de AminoácidosRESUMO
There is increasing evidence supporting the cancer stem cell (CSC) hypothesis, which suggests that a population of tumor cells with stem cell characteristics is responsible for tumor growth, resistance, and recurrence as well as drug resistance. In colorectal cancer, the CD133 antigen defines distinct cell subpopulations that are rich in tumor-initiating cells; however, the drug resistance properties of these CD133-positive cells have not been well defined. The breast cancer resistance protein (BCRP)/ATP-binding cassette subfamily G member 2 (ABCG2) is present on the plasma membrane of many types of human cancer cells and contributes to multidrug resistance during chemotherapy. The results of the present study showed that ABCG2 is expressed in CD133-positive CSCs from human colorectal tumors. Furthermore, the downregulation of ABCG2 expression inhibited the self-renewal capacity of these cells, and significantly enhanced the efficacy of chemotherapy-induced apoptosis in LS174T colon adenocarcinoma cells and CD133-positive colorectal carcinoma cells. Together, these data show that ABCG2 expression correlates with the presence of CD133-positive cancer cells, and thus is a possible therapeutic target for colorectal cancer.
Assuntos
Antígeno AC133/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Autorrenovação Celular , Neoplasias Colorretais/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/metabolismo , Antígeno AC133/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Feminino , Fluoruracila/farmacologia , Células HCT116 , Células HT29 , Humanos , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Colorectal cancer (CRC) is one of the most common diagnosed cancers worldwide. The metastasis and development of resistance to anti-cancer treatment are major challenges in the treatment of CRC. Understanding mechanisms underpinning the pathogenesis is therefore critical in developing novel agents for CRC treatments. A large number of evidence has demonstrated that non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs have functional roles in both the physiological and pathological processes by regulating the expression of their target genes. These molecules are engaged in the pathobiology of neoplastic diseases and are targets for the diagnosis, prognosis and therapy of a variety of cancers, including CRC. In this regard, ncRNAs have emerged as one of the hallmarks of CRC pathogenesis and they also play key roles in metastasis, drug resistance and the stemness of CRC stem cell by regulating various signaling networks. Therefore, a better understanding the ncRNAs involved in the signaling pathways of CRC may lead to the development of novel strategy for diagnosis, prognosis and treatment of CRC. In this chapter, we summarize the latest findings on ncRNAs, with a focus on miRNAs and lncRNAs involving in signaling networks and in the regulation of pathogenic signaling pathways in CRC.
Assuntos
Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica/genética , RNA Neoplásico/genética , RNA não Traduzido/genética , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/patologia , Progressão da Doença , Humanos , MicroRNAs/genética , Metástase Neoplásica , Proteínas de Neoplasias/fisiologia , RNA/genética , RNA Circular , RNA Longo não Codificante/genética , Transdução de Sinais/genéticaRESUMO
The human cytochrome P450 (CYP) superfamily consisting of 57 functional genes is the most important group of Phase I drug metabolizing enzymes that oxidize a large number of xenobiotics and endogenous compounds, including therapeutic drugs and environmental toxicants. The CYP superfamily has been shown to expand itself through gene duplication, and some of them become pseudogenes due to gene mutations. Orthologs and paralogs are homologous genes resulting from speciation or duplication, respectively. To explore the evolutionary and functional relationships of human CYPs, we conducted this bioinformatic study to identify their corresponding paralogs, homologs, and orthologs. The functional implications and implications in drug discovery and evolutionary biology were then discussed. GeneCards and Ensembl were used to identify the paralogs of human CYPs. We have used a panel of online databases to identify the orthologs of human CYP genes: NCBI, Ensembl Compara, GeneCards, OMA ("Orthologous MAtrix") Browser, PATHER, TreeFam, EggNOG, and Roundup. The results show that each human CYP has various numbers of paralogs and orthologs using GeneCards and Ensembl. For example, the paralogs of CYP2A6 include CYP2A7, 2A13, 2B6, 2C8, 2C9, 2C18, 2C19, 2D6, 2E1, 2F1, 2J2, 2R1, 2S1, 2U1, and 2W1; CYP11A1 has 6 paralogs including CYP11B1, 11B2, 24A1, 27A1, 27B1, and 27C1; CYP51A1 has only three paralogs: CYP26A1, 26B1, and 26C1; while CYP20A1 has no paralog. The majority of human CYPs are well conserved from plants, amphibians, fishes, or mammals to humans due to their important functions in physiology and xenobiotic disposition. The data from different approaches are also cross-validated and validated when experimental data are available. These findings facilitate our understanding of the evolutionary relationships and functional implications of the human CYP superfamily in drug discovery.
Assuntos
Biologia Computacional/métodos , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Descoberta de Drogas , Humanos , Relação Estrutura-AtividadeRESUMO
Alogliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor that is a class of relatively new oral hypoglycaemic drugs used in patients with type 2 diabetes (T2DM), can be used as monotherapy or in combination with other anti-diabetic agents, including metformin, pioglitazone, sulfonylureas and insulin with a considerable therapeutic effect. Alogliptin exhibits favorable pharmacokinetic and pharmacodynamic profiles in humans. Alogliptin is mainly metabolized by cytochrome P450 (CYP2D6) and CYP3A4. Dose reduction is recommended for patients with moderate or worse renal impairment. Side effects of alogliptin include nasopharyngitis, upper-respiratory tract infections and headache. Hypoglycaemia is seen in about 1.5% of the T2DM patients. Rare but severe adverse reactions such as acute pancreatitis, serious hypersensitivity including anaphylaxis, angioedema and severe cutaneous reactions such as Stevens-Johnson syndrome have been reported from post-marketing monitoring. Pharmacokinetic interactions have not been observed between alogliptin and other drugs including glyburide, metformin, pioglitazone, insulin and warfarin. The present review aimed to update the clinical information on pharmacodynamics, pharmacokinetics, adverse effects and drug interactions, and to discuss the future directions of alogliptin.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/farmacologia , Piperidinas/farmacologia , Uracila/análogos & derivados , Animais , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Inibidores da Dipeptidil Peptidase IV/farmacocinética , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Interações Medicamentosas , Humanos , Piperidinas/efeitos adversos , Piperidinas/farmacocinética , Piperidinas/uso terapêutico , Uracila/efeitos adversos , Uracila/farmacocinética , Uracila/farmacologia , Uracila/uso terapêuticoRESUMO
Dipeptidyl peptidase-4 (DPP-4) inhibitors are a class of oral antidiabetic drugs that improve glycaemic control without causing weight gain or increasing hypoglycaemic risk in patients with type 2 diabetes mellitus (T2DM). The eight available DPP-4 inhibitors, including alogliptin, anagliptin, gemigliptin, linagliptin, saxagliptin, sitagliptin, teneligliptin, and vildagliptin, are small molecules used orally with identical mechanism of action and similar safety profiles in patients with T2DM. DPP-4 inhibitors may be used as monotherapy or in double or triple combination with other oral glucose-lowering agents such as metformin, thiazolidinediones, or sulfonylureas. Although DPP-4 inhibitors have the same mode of action, they differ by some important pharmacokinetic and pharmacodynamic properties that may be clinically relevant in some patients. The main differences between the eight gliptins include: potency, target selectivity, oral bioavailability, elimination half-life, binding to plasma proteins, metabolic pathways, formation of active metabolite(s), main excretion routes, dosage adjustment for renal and liver insufficiency, and potential drug-drug interactions. The off-target inhibition of selective DPP-4 inhibitors is responsible for multiorgan toxicities such as immune dysfunction, impaired healing, and skin reactions. As a drug class, the DPP-4 inhibitors have become accepted in clinical practice due to their excellent tolerability profile, with a low risk of hypoglycaemia, a neutral effect on body weight, and once-daily dosing. It is unknown if DPP-4 inhibitors can prevent disease progression. More clinical studies are needed to validate the optimal regimens of DPP-4 inhibitors for the management of T2DM when their potential toxicities are closely monitored.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/farmacologia , Animais , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Inibidores da Dipeptidil Peptidase IV/farmacocinética , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Humanos , SegurançaRESUMO
Type 2 diabetes mellitus (T2DM) is caused by insulin resistance and characterized by progressive pancreatic ß-cell dysfunction. This articles reviews the application and limitations of currently approved oral drugs for the treatment of T2DM. Data were retrieved from the literature and well-recognized drug-related databases. Although lifestyle modifications and metformin are the cornerstones of the initial management of T2DM, there is an increasing array of second- and third-line pharmacological agents, including sulphonylureas, insulin, thiazolidinediones and glitazones, α-glucosidase inhibitors, glucagon-like peptide-1 agonists, dipeptidyl peptidase 4 inhibitors and the amylin receptor agonist pramlintide. Current T2DM treatment focuses on reducing blood glucose levels via different mechanisms, including nuclear hormone receptors, nucleic acid binding proteins, transcription factors, voltage-gated K(+) channels, glucosidase, G-protein-coupled receptors and non-receptor serine/threonine protein kinase. Extensive efforts are needed to address the pathogenesis of T2DM, which may facilitate the development of new therapies and the identification of new therapeutic targets to overcome the shortcomings of currently available drugs for T2DM and to achieve therapeutic goals.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , HumanosRESUMO
One of the major mechanisms involved in acetaminophen (APAP)-induced hepatotoxicity is hepatocyte nuclear factor 4α (HNF4α)-mediated activation of pregnane X receptor (PXR) and constitutive androstane receptor (CAR). In the present study, we investigated the role of miR-561 and its target gene DAX-1 encoding a corepressor of HNF4α in the process of APAP-induced hepatotoxicity. We used both human hepatocellular liver carcinoma cell line (HepG2) cells and primary human hepatocytes in this study and monitored the levels of reactive oxygen species, lactate dehydrogenase, and glutathione. Our bioinformatics study suggests an association between miR-561 and DAX-1, but not HNF4α. Treatment of HepG2 cells with APAP significantly reduced the expression of DAX-1 in a concentration-dependent manner. miR-561 was induced by APAP treatment in HepG2 cells. Transfection of HepG2 cells with an miR-561 mimic exacerbated APAP-induced hepatotoxicity. HNF4α is physically associated with DAX-1 in HepG2 cells. A decreased protein level of DAX-1 by APAP treatment was also enhanced by miR-561 mimic transfection in HepG2 cells and primary human hepatocytes. The basal and APAP-induced expression of PXR and CAR was enhanced by miR-561 mimic transfection; however, transfection of HepG2 cells or primary human hepatocytes with a miR-561 inhibitor or DAX-1 small interfering RNA reversed these effects. Additionally, the chromatin immunoprecipitation assay revealed that recruitment of DAX-1 onto the PXR promoter was inversely correlated with the recruitment of peroxisome proliferator-activated receptor-α coactivator-1α and HNF4α on APAP treatment. These results indicate that miR-561 worsens APAP-induced hepatotoxicity via inhibition of DAX-1 and consequent transactivation of nuclear receptors.
Assuntos
Acetaminofen/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/genética , Proteínas Correpressoras/genética , Receptor Nuclear Órfão DAX-1/genética , Regulação para Baixo/genética , Hepatócitos/metabolismo , MicroRNAs/genética , Hiperplasia Suprarrenal Congênita/genética , Hiperplasia Suprarrenal Congênita/metabolismo , Insuficiência Adrenal , Antioxidantes/metabolismo , Linhagem Celular Tumoral , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Proteínas Correpressoras/metabolismo , Receptor Constitutivo de Androstano , Receptor Nuclear Órfão DAX-1/metabolismo , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/metabolismo , Glutationa/metabolismo , Disgenesia Gonadal/genética , Disgenesia Gonadal/metabolismo , Células Hep G2 , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/efeitos dos fármacos , Humanos , Hipoadrenocorticismo Familiar , L-Lactato Desidrogenase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Receptor de Pregnano X , Regiões Promotoras Genéticas/genética , Espécies Reativas de Oxigênio/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima/genéticaRESUMO
BACKGROUND: The purpose of the present study was to evaluate the efficacy of extended pancreatoduodenectomy (EPD) and standard pancreatoduodenectomy (SPD) for ductal adenocarcinoma of the head of the pancreas via meta-analysis. METHODS: Relevant articles (published between 1995 and 2012) were compiled from online data sources. A total of nine studies satisfied the selection criteria, including a total of 973 patients (478 in the SPD group and 495 in the EPD group). Evaluation parameters included 1-, 3-, and 5-year survival, as well as mortality, morbidity, and specific morbidity outcomes. RESULTS: Meta-analysis revealed (1) differences in morbidity (Odds ratio [OR] = 1.740; 95 % confidence interval [CI], 0.840-3.600; P = 0.140), mortality (OR = 0.890; 95 % CI, 0.560-1.400; P = 0.620), 1-year overall survival (OS) rate (OR = 1.20; 95 % CI, 0.490-2.930; P = 0.69), 3-year OS rate (OR = 0.770; 95 % CI, 0.460-1.280; P = 0.190), and 5-year OS rate (OR = 1.12; 95 % CI, 0.690-1.810; P = 0.560) were not significant between EPD and SPD. (2) For bile leak (OR = 2.640; 95 % CI, 1.040-6.700; P = 0.040), pancreatic leak (OR = 1.740; 95 % CI, 1.040-2.91; P = 0.030), delayed gastric emptying (OR = 2.090; 95 % CI, 1.240-3.520; P = 0.006), and lymphatic fistula (OR = 6.120; 95 % CI, 1.06-35.320; P = 0.040) differences between EPD and SPD were significant, whereas other specific morbidities were not significantly different. CONCLUSIONS: Extended pancreatoduodenectomy does not improve 1-, 3-, 5-year OS rates compared to SPD and there is a trend toward increased bile leak, pancreatic leak, delayed gastric emptying, and lymphatic fistula after EPD.
Assuntos
Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/cirurgia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/efeitos adversos , Pancreaticoduodenectomia/métodos , Humanos , Masculino , Taxa de SobrevidaRESUMO
BACKGROUND & AIMS: We aimed at investigating the effects of the targeted transduction of the Wtp53-pPRIME-miR30-shRNA gene into liver cancer cells, under the mediation of anti-alpha fetoprotein scFv-directed lentivirus, and the inhibitory effect of this system on liver cancer cells. METHODS: The result of infection was observed by fluorescence microscopy. Polymerase chain reaction and Western blotting were used to demonstrate the successful transduction and transcription of the Wtp53-pPRIME-miR30-shRNA-IGF1R gene. Cell growth was observed via the Cell-Counting Kit-8 Method, and cell apoptosis was detected by terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling. To observe further the effects of AFP-Wtp53-pPRIME-miR30-shRNA-IGF1R therapy in animals, models of BALB-C nude mice bearing subcutaneous human hepatocellular carcinoma were established. The influence of the growth of subcutaneously transplanted tumor, expression of Wtp53 protein, apoptosis, and microvessel formation on the overall level of AFP-Wtp53 pPRIME-miR30-shRNA-IGF1R were also evaluated. RESULTS: Recombinant lentivirus was successfully constructed, and its functional plaque-forming unit titer was determined as 4.58 × 10(9)plaque-forming units/ml. A positive strand was detected by polymerase chain reaction and Western blotting. Lentiviral construction worked effectively in AFP-positive liver cancer cells. In vitro and in vivo experiments showed that the recombinant lentivirus was more efficacious in inhibiting the proliferation of Hep3B cells. CONCLUSIONS: The Wtp53-pPRIME-miR30-shRNA gene can be subjected to targeted transduction into liver cancer cells under the mediation of anti-alpha fetoprotein scFv-directed lentivirus. The Wtp53-pPRIME-miR30-shRNA system has targeting ability and lethal effects on liver cancer cells.
Assuntos
Carcinoma Hepatocelular/terapia , Terapia Genética , Neoplasias Hepáticas/terapia , MicroRNAs/genética , RNA Interferente Pequeno/genética , Receptor IGF Tipo 1/genética , alfa-Fetoproteínas/genética , Animais , Apoptose , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Lentivirus/genética , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Receptor IGF Tipo 1/análiseRESUMO
BACKGROUND: Bacterial virulence enhancement and drug resistance are major threats to public health worldwide. Interestingly, newly acquired genomic islands (GIs) from horizontal transfer between different bacteria strains were found in Vibrio cholerae, Streptococcus suis, and Mycobacterium tuberculosis, which caused outbreak of epidemic diseases in recently years. RESULTS: Using a large-scale comparative genomic analysis of 1088 complete genomes from all available bacteria (1009) and Archaea (79), we found that newly acquired GIs are often anchored around switch sites of GC-skew (sGCS). After calculating correlations between relative genomic distances of genomic islands to sGCSs and the evolutionary distances of the genomic islands themselves, we found that newly acquired genomic islands are closer to sGCSs than the old ones, indicating that regions around sGCSs are hotspots for genomic island insertion. CONCLUSIONS: Based on our results, we believe that genomic regions near sGCSs are hotspots for horizontal transfer of genomic islands, which may significantly affect key properties of epidemic disease-causing pathogens, such as virulence and adaption to new environments.
Assuntos
Archaea/genética , Bactérias/genética , Genoma Arqueal , Genoma Bacteriano , Ilhas Genômicas , DNA Arqueal/genética , DNA Bacteriano/genética , Transferência Genética Horizontal , Recombinação GenéticaRESUMO
BACKGROUND: Musashi1 (Msi-1), a neural RNA-binding protein, plays an important role in regulating cell differentiation in precursor cells. Recently, aberrant expression of Msi-1 has been detected in several malignancies. However, its role in the progression of colon cancer is largely unknown. MATERIALS AND METHODS: We used Western blotting to examine Msi-1 protein expression in 8 cases of primary colon cancer lesions and paired normal colonic mucosa. Msi-1 expression and clinicopathological significance were determined by immunohistochemical staining in a tissue microarray (TMA) containing 203 cases of primary colon cancer paired with noncancerous tissue and 66 lymph node metastasis (LNM) tissues. RNAi was used to analyze the biological function of Msi-1 in vitro. RESULTS: LNM tissue exhibited a striking increase in Msi-1 expression when compared with primary colon cancer and adjacent normal mucosa (87.9% vs. 64.5% vs. 16.7%, P < .001). Overexpression of Msi-1 was associated with higher clinical stage, T stage, lymph node metastasis, presence of distant metastasis, and Ki-67 positivity. Msi-1 served as an independent prognostic marker whose expression levels correlated with poorer metastasis-free survival (MFS) (HR 5.4; P < .001) and poorer overall survival (OS) (HR 3.8; P < .001). Msi-1 silencing significantly inhibited proliferation ability and attenuated the migration and invasion activity of colon cancer cells. CONCLUSIONS: Our study provides the basis to explore the use of Msi-1 as a novel prognostic biomarker in colon cancer patients. Aberrant overexpression of Msi-1 during metastasis of colon cancer also suggests that it is a potential therapeutic target.
Assuntos
Neoplasias do Colo/metabolismo , Neoplasias do Colo/mortalidade , Proteínas do Tecido Nervoso/metabolismo , Proteínas de Ligação a RNA/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Adesão Celular , Diferenciação Celular , Movimento Celular , Proliferação de Células , Colo/metabolismo , Colo/patologia , Neoplasias do Colo/patologia , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/genética , Prognóstico , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA/antagonistas & inibidores , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Análise Serial de Tecidos , Células Tumorais Cultivadas , Adulto JovemRESUMO
BACKGROUND: Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) and apoptin (VP3) of chicken anemia virus can selectively induce apoptosis in human tumor cell lines by two different pathways. Salmonella not only delivers functional genes to mammalian cells but also possesses antitumor activity and therefore could be adopted as a novel vector for anticancer therapy. MATERIALS AND METHODS: TRAIL and VP3 genes were cloned into a pBudCE4.1 vector and delivered by attenuated Salmonella typhimurium into gastric cancer cells, and their expression and antitumor effects in nude mice were monitored by Western blot, fluorescence microscopy, MTT assay, TUNEL staining, and immunohistochemistry. RESULTS: pBud-VP3 and pBud-TRAIL-VP3 plasmids were constructed to express TRAIL and apoptin in gastric cancer cells, leading to inhibition of cancer cell proliferation after 48 hours (P < 0.05). TRAIL and VP3 genes in pBudCE4.1 vector were also successfully delivered by attenuated S. typhimurium into gastric cancer cells in vivo, in which both TRAIL and apoptin were expressed. In vivo data indicated that S. typhimurium carring pBud-TRAIL-VP3 induced significant cell growth inhibition and tumor regression (P < 0.05). Moreover, expression of TRAIL and apoptin increased the expression of caspase-3 and caspase-9, resulting in enhanced apoptosis. CONCLUSION: Delivery of TRAIL and VP3 genes by attenuated S. typhimurium can significantly inhibit the growth of gastric cancer cells in vitro and in vivo.
Assuntos
Proteínas do Capsídeo/genética , Terapia Genética , Salmonella typhimurium/genética , Neoplasias Gástricas/terapia , Ligante Indutor de Apoptose Relacionado a TNF/genética , Animais , Apoptose , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Gástricas/patologiaRESUMO
[This corrects the article DOI: 10.1155/2017/1202710.].
RESUMO
BACKGROUND: As a disease with extremely complex molecular mechanisms, many deregulated miRNAs have been identified in colon cancer. Few studies have been performed by using Ingenuity Pathways Analysis (IPA) to predict miRNAs specifically expressed in colon cancer. METHODS: A characteristic microRNA-target network of colon cancer was explored using IPA. Then the clinical significance of miR-19b-3p was evaluated in 211 colon cancer patients. The roles of miR-19b-3p and its candidate target gene, SMAD4, in colon cancer progression were examined both in vitro and in vivo. RESULTS: Bioinformatics analysis showed that 15 microRNAs screened by IPA were significantly correlated with malignant biological behaviors of colon cancer. miR-19b-3p was the most significantly upregulated candidate based on the validation experiment using 211 colon cancer samples. High expression of miR-19b-3p was significantly associated with high N stage (P < 0.001), high AJCC stage (P < 0.001), poor histologic grade (P = 0.032), frequent venous and lymphatic invasion (P = 0.027), and liver metastasis (P < 0.001). Survival analysis revealed that miR-19b-3p was an independent prognostic factor associated with colon cancer patient's overall survival (OS) and disease-free survival (DFS). miR-19b-3p promoted proliferation and chemoresistance of colon cancer cells, but had no effect on invasion in vitro, along with tumorigenesis in vivo. In addition, we confirmed that miR-19b-3p mediates resistance to oxaliplatin-based chemotherapy via SMAD4. CONCLUSIONS: Our findings demonstrate the role of miR-19b-3p-SMAD4 axis in colon cancer progression, which may become a potential therapeutic target against chemotherapy resistance.
Assuntos
Neoplasias Colorretais/patologia , Biologia Computacional/métodos , Resistencia a Medicamentos Antineoplásicos , MicroRNAs/genética , Proteína Smad4/genética , Animais , Células CACO-2 , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/genética , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HT29 , Humanos , Masculino , Camundongos , Estadiamento de Neoplasias , Transplante de Neoplasias , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Regulação para CimaRESUMO
Deregulation of G protein-coupled receptor kinase 3 (GRK3), which belongs to a subfamily of kinases called GRKs, acts as a promoter mechanism in some cancer types. Our study found that GRK3 was significantly overexpressed in 162 pairs of colon cancer tissues than in the matched noncancerous mucosa (P < 0.01). Based on immunohistochemistry staining of TMAs, GRK3 was dramatically stained positive in primary colon cancer (130/180, 72.22%), whereas it was detected minimally or negative in paired normal mucosa specimens (50/180, 27.78%). Overexpression of GRK3 was closely correlated with AJCC stage (P = 0.001), depth of tumor invasion (P < 0.001), lymph node involvement (P = 0.004), distant metastasis (P = 0.016), and histologic differentiation (P = 0.004). Overexpression of GRK3 is an independent prognostic indicator that correlates with poor survival in colon cancer patients. Consistent with this, downregulation of GRK3 exhibited decreased cell growth index, reduction in colony formation ability, elevated cell apoptosis rate, and impaired colon tumorigenicity in a xenograft model. Hence, a specific overexpression of GRK3 was observed in colon cancer, GRK3 potentially contributing to progression by mediating cancer cell proliferation and functions as a poor prognostic indicator in colon cancer and potentially represent a novel therapeutic target for the disease.
Assuntos
Neoplasias do Colo/patologia , Quinase 3 de Receptor Acoplado a Proteína G/genética , Quinase 3 de Receptor Acoplado a Proteína G/metabolismo , Regulação para Cima , Animais , Apoptose , Estudos de Casos e Controles , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Células HT29 , Humanos , Masculino , Camundongos , Metástase Neoplásica , Estadiamento de Neoplasias , Transplante de Neoplasias , Prognóstico , Análise de SobrevidaRESUMO
Digoxin is a member of cardiac glycosides and recent studies show that digoxin plays anticancer role in several types of cancer. However, the anticancer effects and mechanism of digoxin in leukemia is largely unknown. Her, our data show that digoxin treatment significantly inhibits leukemia cell viability. In addition, digoxin treatment significantly induced apoptosis and G2/M cell cycle arrest in leukemia cells. Furthermore, we demonstrated that digoxin treatment inactivate that oncogenic pathway Akt/mTOR signaling in leukemia cells. In addition, our data show that digoxin treatment induces activation of unfolded protein response (UPR) signaling in leukemia cells. Interestingly, our in vitro and in vivo experiments show that combination treatment of digoxin and UPR inhibitor can synergistically suppress leukemia growth and induces apoptosis and cell cycle arrest compared to single drug treatment. In summary, our findings indicate that digoxin has potential anticancer effects on leukemia. The combination of digoxin and UPR signaling inhibitor can exerts synergistic anticancer activity against leukemia. © 2017 BioFactors, 43(6):812-820, 2017.
Assuntos
Adenina/análogos & derivados , Antineoplásicos/farmacologia , Digoxina/farmacologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Indóis/farmacologia , Leucemia Eritroblástica Aguda/tratamento farmacológico , Adenina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Combinação de Medicamentos , Sinergismo Farmacológico , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Humanos , Células K562 , Leucemia Eritroblástica Aguda/genética , Leucemia Eritroblástica Aguda/metabolismo , Leucemia Eritroblástica Aguda/patologia , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células THP-1 , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Psoriasis vulgaris is a chronic inflammatory skin disease, stubbornly intractable, with substantial consequences for patient physical and mental welfare. Approaches currently available to treat psoriasis are not satisfactory due to undesirable side-effects or expense. Psoriasis is characterized by hyperproliferation and inflammation. Oxymatrine, an active component extracted from Sophora flavescens, has been demonstrated to possess anti-proliferation, anti-inflammatory, anti-tumorigenic, immune regulation and pro-apoptotic properties. This investigation presents a detailed retrospective review examining the effect of Oxymatrine on psoriasis and investigates the mechanisms underlying patient responses to Oxymatrine. We confirm that Oxymatrine administration significantly reduced the Psoriasis Area Severity Index score, with high efficacy compared to the control group. In addition, we have found that Oxymatrine significantly inhibits the viability, proliferation and differentiation of human keratinocyte in vitro. Immunohistochemical analysis indicates Oxymatrine significantly suppresses the expression of Pan-Cytokeratin, p63 and keratin 10. The results indicate that the suppression of p63 expression may lead to the anti-proliferation effect of Oxymatrine on human skin keratinocytes. Oxymatrine does not affect the formation of basement membrane, which is very important to maintain the normal function of human skin keratinocytes. In summary, Oxymatrine offers an effective, economical, and safe treatment for patients presenting with intractable psoriasis vulgaris.