RESUMO
AIMS: In this study, we attempted to increase the productivity of Candida glycerinogenes yeast for ethanol production from non-detoxified sugarcane bagasse hydrolysates (NDSBH) by identifying the hexose transporter in this yeast that makes a high contribution to glucose consumption, and by adding additional copies of this transporter and enhancing its membrane localisation stability (MLS). METHODS AND RESULTS: Based on the knockout and overexpression of key hexose transporter genes and the characterisation of their promoter properties, we found that Cghxt4 and Cghxt6 play major roles in the early and late stages of fermentation, respectively, with Cghxt4 contributing most to glucose consumption. Next, subcellular localisation analysis revealed that a common mutation of two ubiquitination sites (K9 and K538) in Cghxt4 improved its MLS. Finally, we overexpressed this Cghxt4 mutant (Cghxt4.2A) using a strong promoter, PCgGAP , which resulted in a significant increase in the ethanol productivity of C. glycerinogenes in the NDSBH medium. Specifically, the recombinant strain showed 18 and 25% higher ethanol productivity than the control in two kinds of YP-NDSBH medium (YP-NDSBH1G160 and YP-NDSBH2G160 ), respectively. CONCLUSIONS: The hexose transporter mutant Cghxt4.2A (Cghxt4K9A,K538A ) with multiple copies and high MLS was able to significantly increase the ethanol productivity of C. glycerinogenes in NDSBH. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results provide a promising strategy for constructing efficient strains for ethanol production.
Assuntos
Saccharum , Candida/genética , Celulose , Etanol , Fermentação , Hidrólise , Proteínas de Transporte de Monossacarídeos , PichiaRESUMO
Objective: To observe the efficacy and safety of albumin-bound paclitaxel in the treatment of metastatic breast cancer. Methods: Multi-center data of patients who accepted single-drug albumin-bound paclitaxel or combination regimens from 2013 to 2019 were collected and the efficacy and safety were evaluated. Kaplan-Meier method was used for survival analysis, while Log-rank test was used to compare the survival rates. Results: A total of 203 advanced breast cancer cases were enrolled. The median progression-free survival time (PFS) lasted for 4 months, the median overall survival(OS)was 14 months, objective response rate (ORR) was 36.0% while the disease control rate (DCR) was 81.3%. The ORRs of Luminal, human epidermal growth factor receptor 2 (HER2) overexpression and triple-negative breast cancer patients underwent albumin-bound paclitaxel treatment were 37.3%, 45.5% and 31.0%, respectively, the DCRs were 85.5%, 68.2% and 78.9%, respectively. The OS of patients with relapse or metastasis who accepted less than two and more than two chemotherapy regimens were 22 months and 11 months (P<0.000 1), the ORRs were 44.9% vs 30.4%, DCRs were 87.2% vs 77.6% (P=0.018). The ORR and DCR of patients who accepted traditional paclitaxel treatment before the albumin-bound paclitaxel treatment were 35.8% and 82.1%, respectively. The common adverse reaction of these patients was numbness of limbs, which incidence rate was 64.5% (131/203), and 61.1% (124/203) were degree 1 to 2. Other adverse reactions including decreased white blood cells, which incidence rate was 56.1% (114/203); nausea and vomit, which incidence rate was 36.9% (75/203); anemia, which incidence rate was 21.2% (43/203); decreased platelet, which incidence rate was 18.7% (38/203); hepatic dysfunction, which incidence rate was 18.2% (37/203). Conclusions: Albumin-bound paclitaxel single or combination regimen is still significant efficient for various molecular subtypes of breast cancer patients or patients with traditional paclitaxel resistance or multi-line chemotherapy failure. Early usage has better prognosis, controllable adverse reaction and prominent clinical application value.
Assuntos
Paclitaxel Ligado a Albumina , Neoplasias de Mama Triplo Negativas , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Humanos , Recidiva Local de Neoplasia , Paclitaxel , Neoplasias de Mama Triplo Negativas/tratamento farmacológicoRESUMO
Objective: To construct the competitive endogenous RNA (ceRNA) network related to gastric cancer and explore the molecular mechanism. Methods: The expression profiles of lncRNA, miRNA and mRNA in gastric cancer and paracancer tissues were analyzed by biochip technology, edgeR package in R software was used to filtrate differential expression genes (multiple change of >1.5 times, P<0.05) and volcano map was drawn. Based on the online miRNA-lncRNA prediction tool lncBase database and the miRNA Target gene prediction database (miRTarBase, target-scan, miRDB, starBase), the relationship between miRNA, lncRNA and mRNA was predicted. Cytoscape software was used to construct lncRNA-miRNA-mRNA ceRNA network and key genes (hub genes) were identified based on cytohubba calculation of degree score of each node. Then Hub genes related to the prognosis of gastric cancer were verified in the TCGA database. The GO and KEGG enrichment analysis of differentially expressed mRNA was performed using the online biological information annotation database DAVID, P<0.05 and false discovery rate (FDR)<0.05 were used as cut-off criteria. R software was used to download the RNA sequencing data and mirna-seq data of gastric cancer and adjacent tissues in TCGA database, edgeR package was used to screen out differentially expressed mRNA, miRNA and lncRNA, and some differentially expressed genes in our data were verified. In OncoLnc database, STAD project of TCGA data was selected and hub gene was input. Patients were divided into two groups based on the median value for hub genes and Kaplan-meier analysis was performed. Results: The differentially expressed 766 mRNA, 110 lncRNA and 10 miRNA were screened out, among them 90 mRNA, 4 lncRNA and 6 miRNA were used to construct the ceRNA network, and 2 of the 20 hub genes were related to the prognosis of patients. MLK7-AS1, SPP1, SULF1, hsa-miR-1307-3p were upregulated in gastric cancer tissues from our biochip, while MT2A, MT1X were downregulated, which were consistent with the results of TCGA gastric cancer database. The differentially expressed mRNAs were significantly enriched in the biological process (BP) and the mineral absorption pathway. CHST1 was negatively correlated while miR-183-5p was positively corelated with the survival of patients. Conclusion: The establishment of ceRNA network for gastric cancer is conducive to further understanding of the molecular biological mechanism. CHST1 and miR-183-5p can be used as prognostic factors of gastric cancer.
Assuntos
Redes Reguladoras de Genes/genética , Neoplasias Gástricas/genética , Humanos , MicroRNAs/genética , Prognóstico , RNA Longo não Codificante/genética , RNA Mensageiro/genética , SoftwareRESUMO
Objective: To investigate the clinical outcomes of advanced non-small cell lung cancer (NSCLC) treated by apatinib regimens and the influence of VEGFR2-906T>C polymorphism. Methods: A total of 109 patients with advanced NSCLC who were treated by apatinib after three and more lines from March 2015 to December 2017 in the Department of Oncology of the First Affiliated Hospital of Zhengzhou University were included in this study. Overall response rates were evaluated after 2 cycles, then progression free survival (PFS) and overall survival (OS) were investigated, and safety data were recorded. Additionally, peripheral blood and the biopsy tissue specimens of some NSCLC patients were collected for the genotyping of genetic variation and VEGFR2 gene mRNA expression, respectively. The association between genotype and other characteristics and VEGFR2 gene mRNA expression were analyzed. The univariate analysis of genotypes and prognosis was carried out by Kaplan-Meier survival analysis, and multivariate analysis were adjusted by Cox regression analysis. Results: The treatment effect could be evaluated in all the 109 patients, among them, complete remission (CR) 0 case, partial remission (PR) 19 case, stable disease (SD) 58 case, progression disease (PD) 32 case. Overall response rate (ORR) was 17.43%, disease control rate (DCR) was 70.64%, median PFS was 4.35 months, median OS was 8.35 months. Of the polymorphisms analyzed, only -906T>C was of clinical significance. The prevalence of -906T>C in VEGFR2 among the study population were as follows: TT genotype 64 cases (58.72%), TC genotype 37 cases (33.94%), CC genotype 8 cases (7.34%), minor allele frequency of -906T>C was 0.24. The distribution of three genotypes was in accordance with Hardy-Weinberg Equilibrium (P=0.418). CC and TC genotype patients were merged in the comparison of clinical outcomes. The analysis of patients with different genotypes found that the ORR of CC/TC genotypes and TT genotypes were 13.33% and 20.31% (P=0.377), respectively. And the median PFS of patients with CC/TC genotype and TT genotype were 3.25 and 5.35 months, respectively, which was statistically significant (P=0.007). In terms of OS, the median OS of the two genotypes were 7.35 and 9.15 (P=0.014), respectively. Adjusted in multivariate Cox regression analysis of PFS, TC/CC genotypes were an independent factor for PFS (OR=1.83, P=0.015). The correlation between -906T>C and adverse reactions was not found in the safety analysis. Additionally, of the 69 biopsy tissue specimens, gene expression analysis was conducted. And the results show that the mRNA expression of VEGFR2 in cancer tissues of the patients with CC/TC genotypes were significantly higher than those of the TT genotype patients (P<0.001). Conclusions: Apatinib is safe and effective for patients with advanced non-small cell in multiline therapy. VEGFR2 -906T>C CC/TC genotype has a worse effect on apatinib multiline treatment in patients with advanced NSCLC.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Genótipo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , PiridinasRESUMO
AIMS: This study aimed to strengthen the reducing equivalent generation in Klebsiella pneumoniae for improving 1,3-propanediol (PDO) production. METHODS AND RESULTS: Disruption of the arcA gene activated the transcription levels of the TCA cycle genes and thus increased the NADH/NAD+ ratio by 54·2%, leading to the improved PDO titre and yield per cell from 16·1 g l-1 and 4·0 g gDCW-1 to 18·8 g l-1 and 6·4 g gDCW-1 respectively. Further ldhA gene deletion eliminated lactate accumulation and promoted the PDO titre to 19·9 g l-1 . Finally, the glucose effect was weakened by deleting the crr gene to enhance the co-utilization of glucose and glycerol, resulting in the increased PDO production to 23·8 g l-1 with the glycerol conversion rate of 59·5%. The PDO titre in bioreactor was promoted from 61·2 to 78·1 g l-1 . CONCLUSIONS: Deletions of the arcA and the crr genes showed positive effects on the TCA cycle activity and the co-utilization of glucose and glycerol, leading to the strengthened reducing equivalent generation and the improved PDO titre by 47·8% in shaker. The PDO titre in the bioreactor was enhanced to 78·1 g l-1 . SIGNIFICANCE AND IMPACT OF THE STUDY: This study provided novel information on generating reducing equivalent for the PDO biosynthesis by strengthening the TCA cycle and weakening the glucose effect in K. pneumoniae.
Assuntos
Proteínas de Bactérias/genética , Ciclo do Ácido Cítrico , Glucose/metabolismo , Klebsiella pneumoniae/genética , Propilenoglicóis/metabolismo , Proteínas de Bactérias/metabolismo , Reatores Biológicos , Glicerol/metabolismo , Klebsiella pneumoniae/metabolismo , Ácido Láctico/metabolismoRESUMO
BACKGROUND: Androgenetic alopecia (AGA), or male pattern baldness (MPB), is the most common form of hair loss in males. A combination of genetic and androgen causes have been suggested as factors that contribute to the development of AGA. However, the specific molecular mechanisms that underly AGA remain largely unknown. Long non-coding RNAs (lncRNAs), a new class of regulatory non-coding RNAs that are longer than 200 nucleotides, have been shown to play important roles in a number of cellular processes, including transcription, chromosome remodelling and post-transcriptional processing. The dysregulation of lncRNAs is associated with many forms of diseases, but it remains unknown whether lncRNAs are associated with AGA. OBJECTIVE: The aim of this study was to identify AGA-associated lncRNAs and predict the potential roles of these lncRNAs in AGA. METHODS: A genomewide microarray was used to identify lncRNAs that are differentially expressed between AGA and adjacent normal tissues. Real-time qRT-PCR was used to validate the microarray data. RESULTS: A large number of lncRNAs were differentially expressed (fold change >2.4) between AGA and adjacent normal tissues. Of these, 770 were upregulated and 1373 were downregulated. Moreover, pathway analysis revealed that 53 functional pathways were associated with the upregulated transcripts, while 11 pathways were associated with the downregulated transcripts. CONCLUSION: To our knowledge, this is the first study to investigate AGA-associated lncRNAs. lncRNA profiles are altered in AGA, and these lncRNAs and their target genes may serve as novel candidates for preventing and treating AGA.
Assuntos
Alopecia/genética , Perfilação da Expressão Gênica , RNA Longo não Codificante/genética , Adulto , China , Regulação para Baixo , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Regulação para CimaRESUMO
Severe multiple injury (SMI) can induce multiple organ dysfunction syndrome (MODS) and easily result in complications, as well as having a high mortality rate. To explore the curative effect of continuous vena-venous hemofiltration (CVVH) in treating MODS and its effect on serum tumor necrosis factor (TNF)-α interleukin (IL)-10 and nitric oxide (NO), we selected 200 patients who suffered from SMI and received treatment in the First Affiliated Hospital of Zhengzhou University between April 2012 and April 2014 as research subjects. All patients were treated with CVVH. Vital signs, blood oxygen pressure (PaO(2)) and oxygenation index (OI) of artery, electrolyte and acid-base balance were observed before and after treatment. Before treatment, 1 h and 12 h after the start of treatment, and at the end of treatment, TNF-α and IL-10 concentrations in serum and ultrafiltrate were tested using enzyme linked immunosorbent assay, and NO concentration in serum and ultrafiltrate was detected using nitrate reduction method. After treatment, heart rate and respiratory rate of patients had significant decline (P less than 0.05) and average arterial pressure rose remarkably (P less than 0.05); blood urea nitrogen and creatinine decreased (P less than 0.05 or 0.01); PaO(2) and OI were both significantly increased (P less than 0.01); hyperkalemia and acidosis were effectively corrected (P less than 0.01); but differences of Na+, Ca2+ and Cl- before and after treatment had no statistical significance (P>0.05). Serum IL-10 concentration had a significant increase after treatment, while TNF-α and NO concentrations had a significant decline after treatment. A small quantity of IL-10, but not of TNF-α, was detected from ultrafiltrate. Concentration of NO in ultrafiltrate was higher. It can be concluded that CVVH can effectively relieve clinical symptoms of MODS patients, improve function of organs, correct electrolyte disturbance and acid-base imbalance and eliminate TNF-α and NO in serum, which is effective in improving the ratio of successful rescue of patients developing MODS.
Assuntos
Hemofiltração/métodos , Insuficiência de Múltiplos Órgãos/terapia , Ferimentos e Lesões/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Interleucina-10/sangue , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/sangue , Óxido Nítrico/sangue , Oxigênio/sangue , Fator de Necrose Tumoral alfa/sangueRESUMO
It is still controversial whether X-ray repair cross-complementing group (XRCC1) gene polymorphisms (Arg194Trp and Arg399Gln) are associated with the clinical outcome of platinum-based chemotherapy in gastric cancer patients based on published studies. Meta-analysis was performed to provide a systematic review of the findings. Eligible articles from the PubMed, SinoMed, and CNKI databases before September 1, 2012, were selected. Objective response (complete response + partial response vs progressive disease + stable disease), progress-free survival (PFS) and overall survival (OS) were applied to evaluate clinical outcomes. We calculated the odds ratio or hazard risk (HR) with 95% confidence interval (CI) using the STATA software. Eleven eligible articles including 1274 gastric cancer patients with platinum-based treatment were enrolled in our meta-analysis. The results indicated that the A allele of the XRCC1 Arg399Gln polymorphism was significantly associated with poor OS (HR = 1.40; 95%CI = 1.04-1.90) of gastric cancer but not for platinum-based chemotherapy response or PFS. No significant associations were observed between XRCC1 Arg194Trp and objective response. The data suggest that the XRCC1 Arg399Gln polymorphism may be a prognostic biomarker of OS for platinum-based gastric cancer treatment. However, further cohorts with larger sample sizes from different ethnic backgrounds and with improved experimental design are needed to confirm these findings.
Assuntos
Antineoplásicos/uso terapêutico , Proteínas de Ligação a DNA/genética , Platina/uso terapêutico , Polimorfismo Genético , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Alelos , Genótipo , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único , Prognóstico , Neoplasias Gástricas/mortalidade , Resultado do Tratamento , Proteína 1 Complementadora Cruzada de Reparo de Raio-XRESUMO
AIMS/HYPOTHESIS: Up-regulation of the receptor for AGEs (RAGE) and its ligands in diabetes has been observed in various tissues. Here, we sought to determine levels of RAGE and one of its most important ligands, S100B, in diabetic retina, and to investigate the regulatory role of S100B and RAGE in Müller glia. METHODS: Streptozotocin-diabetes was induced in Sprague-Dawley rats. RAGE, S100B and glial fibrillary acidic protein (GFAP) were detected in retinal cryosections. In parallel, the human retinal Müller cell line, MIO-M1, was maintained in normal glucose (5.5 mmol/l) or high glucose (25 mmol/l). RAGE knockdown was achieved using small interfering RNA (siRNA), while soluble RAGE was used as a competitive inhibitor of RAGE ligand binding. RAGE, S100B and cytokines were detected using quantitative RT-PCR, western blotting, cytokine protein arrays or ELISA. Activation of mitogen-activated protein kinase (MAPK) by RAGE was determined by western blotting. RESULTS: Compared with non-diabetic controls, RAGE and S100B were significantly elevated in the diabetic retina with apparent localisation in the Müller glia, occurring concomitantly with upregulation of GFAP. Exposure of MIO-M1 cells to high glucose induced increased production of RAGE and S100B. RAGE signalling via MAPK pathway was linked to cytokine production. Blockade of RAGE prevented cytokine responses induced by high glucose and S100B in Müller glia. CONCLUSIONS/INTERPRETATION: Hyperglycaemia in vivo and in vitro exposure to high glucose induce upregulation of RAGE and its ligands, leading to RAGE signalling, which links to pro-inflammatory responses by retinal Müller glia. These data shed light on the potential clinical application of RAGE blockade to inhibit the progression of diabetic retinopathy.
Assuntos
Hiperglicemia/complicações , Mediadores da Inflamação/metabolismo , Neuroglia/metabolismo , Receptores Imunológicos/fisiologia , Retina/metabolismo , Retinite/etiologia , Animais , Linhagem Celular , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Neuropatias Diabéticas/metabolismo , Neuropatias Diabéticas/patologia , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Glucose/efeitos adversos , Glucose/farmacologia , Humanos , Hiperglicemia/etiologia , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Masculino , Neuroglia/patologia , Ratos , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Retina/citologia , Retina/patologia , Retinite/genética , Retinite/metabolismo , EstreptozocinaRESUMO
OBJECTIVE: To investigate the role of micro-ribonucleic acid-29b (miR-29b) in rats with gestational diabetes mellitus (GDM) through the phosphatidylinositol 3-kinase (PI3K)/serine/threonine kinase (Akt) signal and its mechanism by establishing rat models of GDM. MATERIALS AND METHODS: Rat models of GDM were constructed, and then the expression levels of miR-29b, total PI3K, phosphorylated PI3K (p-PI3K), total Akt and phosphorylated Akt (p-Akt) in the model group and control group were measured via Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and Western blotting assays, and the association between miR-29b expression and total PI3K expression was analyzed. In addition, miR-29b mimics and inhibitors were used to further explore the regulatory pathway, and the influences of miR-29b mimics and inhibitors on PI3K and Akt phosphorylation in GDM rats, characteristic indicators of oxidative stress such as superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) in liver tissues of GDM rats, and fasting blood glucose in GDM rats were studied. RESULTS: Compared with those in the control group, miR-29b expression was lowered in rat models of GDM, while PI3K/Akt signal expression was increased. In rats with GDM, miR-29b expression was prominently negatively correlated with total PI3K expression (r=-0.777, p=0.007, p<0.01). MiR-29b mimics could reduce PI3K and Akt phosphorylation, increase SOD and CAT expression levels and decrease MDA content (p<0.05). Moreover, miR-29b mimics significantly lowered the blood glucose level in rats with GDM (p<0.05). CONCLUSIONS: MiR-29b mimics can alleviate oxidative stress and reduce blood glucose by inhibiting the PI3K/Akt signal transduction.
Assuntos
Diabetes Gestacional/genética , Regulação para Baixo , MicroRNAs/genética , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Diabetes Gestacional/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Estresse Oxidativo , Fosforilação , Gravidez , Ratos , Transdução de SinaisRESUMO
Using cre/loxP gene targeting, transgenic mice with muscle-specific inactivation of the GLUT4 gene (muscle GLUT4 KO) were generated and shown to develop a diabetes phenotype. To determine the mechanism, we examined insulin-stimulated glucose uptake and metabolism during hyperinsulinemic-euglycemic clamp in control and muscle GLUT4 KO mice before and after development of diabetes. Insulin-stimulated whole body glucose uptake was decreased by 55% in muscle GLUT4 KO mice, an effect that could be attributed to a 92% decrease in insulin-stimulated muscle glucose uptake. Surprisingly, insulin's ability to stimulate adipose tissue glucose uptake and suppress hepatic glucose production was significantly impaired in muscle GLUT4 KO mice. To address whether these latter changes were caused by glucose toxicity, we treated muscle GLUT4 KO mice with phloridzin to prevent hyperglycemia and found that insulin-stimulated whole body and skeletal muscle glucose uptake were decreased substantially, whereas insulin-stimulated glucose uptake in adipose tissue and suppression of hepatic glucose production were normal after phloridzin treatment. In conclusion, these findings demonstrate that a primary defect in muscle glucose transport can lead to secondary defects in insulin action in adipose tissue and liver due to glucose toxicity. These secondary defects contribute to insulin resistance and to the development of diabetes.
Assuntos
Diabetes Mellitus Tipo 2/genética , Glucose/toxicidade , Resistência à Insulina/genética , Proteínas de Transporte de Monossacarídeos/genética , Proteínas Musculares/genética , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Idade de Início , Animais , Depressão Química , Modelos Animais de Doenças , Glucose/farmacocinética , Transportador de Glucose Tipo 4 , Hiperglicemia/tratamento farmacológico , Hiperglicemia/prevenção & controle , Insulina/administração & dosagem , Insulina/farmacologia , Insulina/uso terapêutico , Sistemas de Infusão de Insulina , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Knockout , Proteínas de Transporte de Monossacarídeos/deficiência , Proteínas de Transporte de Monossacarídeos/metabolismo , Proteínas Musculares/deficiência , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Florizina/farmacologia , Florizina/uso terapêutico , Estado Pré-Diabético/tratamento farmacológico , Estado Pré-Diabético/metabolismo , Transporte Proteico/efeitos dos fármacosRESUMO
RhoA is involved in multiple cellular processes, including cytoskeletal organization, gene expression, and transformation. These processes are mediated by a variety of downstream effector proteins. However, which effectors are involved in cellular transformation and how these proteins are activated following interaction with Rho remains to be established. A unique feature that distinguishes the Rho family from other Ras-related GTPases is the insert region, which may confer Rho-specific signaling events. Here we report that deletion of the insert region does not result in impaired effector binding. Instead, this insert deletion mutant (RhoDeltaRas, in which the insert helix has been replaced with loop 8 of Ras) acted in a dominant inhibitory fashion to block RhoA-induced transformation. Since RhoDeltaRas failed to promote stress fiber formation, we examined the ability of this mutant to bind to and subsequently activate Rho kinase. Surprisingly, RhoDeltaRas-GTP coprecipitated with Rho kinase but failed to activate it in vivo. These data suggested that the insert domain is not required for Rho kinase binding but plays a role in its activation. The constitutively active catalytic domain of Rho kinase did not promote focus formation alone or in the presence of Raf(340D) but cooperated with RhoDeltaRas to induce cellular transformation. This suggests that Rho kinase needs to cooperate with additional Rho effectors to promote transformation. Further, the Rho kinase catalytic domain reversed the inhibitory effect of RhoDeltaRas on Rho-induced transformation, suggesting that one of the downstream targets of Rho-induced transformation abrogated by RhoDeltaRas is indeed Rho kinase. In conclusion, we have demonstrated that the insert region of RhoA is required for Rho kinase activation but not for binding and that this kinase activity is required to induce morphologic transformation of NIH 3T3 cells.
Assuntos
Transformação Celular Neoplásica/genética , Proteína rhoA de Ligação ao GTP/genética , Células 3T3 , Animais , Ativação Enzimática/genética , Regulação Enzimológica da Expressão Gênica , Camundongos , Deleção de Sequência , Transdução de Sinais/genéticaRESUMO
Accumulating studies have demonstrated the importance of long noncoding RNAs (lncRNAs) during oncogenic transformation. However, because most lncRNAs are currently uncharacterized, the identification of novel oncogenic lncRNAs is difficult. Given that intergenic lncRNA have substantially less sequence conservation patterns than protein-coding genes across species, evolutionary conserved intergenic lncRNAs are likely to be functional. The current study identified a novel intergenic lncRNA, LINC00461 (ECONEXIN) using a combined approach consisting of searching lncRNAs by evolutionary conservation and validating their expression in a glioma mouse model. ECONEXIN was the most highly conserved intergenic lncRNA containing 83.0% homology with the mouse ortholog (C130071C03Rik) for a region over 2500 bp in length within its exon 3. Expressions of ECONEXIN and C130071C03Rik were significantly upregulated in both human and mouse glioma tissues. Moreover, the expression of C130071C03Rik was upregulated even in precancerous conditions and markedly increased during glioma progression. Functional analysis of ECONEXIN in glioma cell lines, U87 and U251, showed it was dominantly located in the cytoplasm and interacted with miR-411-5p via two binding sites within ECONEXIN. Inhibition of ECONEXIN upregulated miR-411-5p together with the downregulation of its target, Topoisomerase 2 alpha (TOP2A), in glioma cell lines, resulting in decreased cell proliferation. Our data demonstrated that ECONEXIN is a potential oncogene that regulates TOP2A by sponging miR-411-5p in glioma. In addition, our investigative approaches to identify conserved lncRNA and their molecular characterization by validation in mouse tumor models may be useful to functionally annotate novel lncRNAs, especially cancer-associated lncRNAs.
Assuntos
Antígenos de Neoplasias/metabolismo , Neoplasias Encefálicas/metabolismo , Carcinogênese/genética , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Glioma/metabolismo , MicroRNAs/metabolismo , Oncogenes , RNA Longo não Codificante/metabolismo , Animais , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Proliferação de Células , Sequência Conservada , Progressão da Doença , Regulação para Baixo , Glioma/genética , Humanos , Camundongos , Proteínas de Ligação a Poli-ADP-Ribose , Lesões Pré-Cancerosas/genética , RNA Longo não Codificante/genética , Complexo de Inativação Induzido por RNA/metabolismo , Regulação para CimaRESUMO
Stromal cell populations in the tumor microenvironment (TME) play a critical role in the oncogenesis and metastasis of renal cell carcinoma. In this study, we found that there are α-smooth muscle actin positive (α-SMA (+)) cells in the stroma of clear cell renal cell carcinoma (ccRCC) tissues, and their numbers are significantly associated with poor survival in ccRCC patients. Interleukin 6 (IL-6) is a critical diver that induces α-SMA (+) cells in ccRCC tissues via promotion of epithelial to mesenchymal transition (EMT) and stimulates migration and invasion in ccRCC. Peritumoral CD4+ T cells are the main source of IL-6 in ccRCC tissues. In addition to biochemical factors, mechanical compression within tumors affects tumor cell behavior. Tumors grown in a confined space exhibit intratumoral compressive stress and, with sufficient pressure, stress-stimulated migration of cancer cells. Moreover, a combination of IL-6 secreted by CD4+ T cells and growth-induced solid stress further contributes to the regulation of cancer cell morphogenesis, EMT and acquisition of a stemness phenotype. The effects in the combination group were driven by the Akt/GSK-3ß/ß-catenin signaling pathway, and deregulation of ß-catenin expression was predictive of poor outcome in ccRCC patients. Notably, the expression of a cancer stem cell marker, CD44, was correlated with T stage, high Fuhrman grade and metastasis in ccRCC. These data provide evidence for new stress-reducing and IL-6 targeting strategies in cancer therapy.
RESUMO
The glioblastoma includes brain tumors, which are very aggressive in nature and are among the most common brain tumors in adults. Latest therapeutic avenues involve combination approach. However, the observed median survival is still no more than 15 months. Moreover, there is a scarcity of accurate pre-clinical model systems, which in turn resulted in limited treatment options for this disease. Cancer stem cells are attractive avenues in anticancer research against glioblastoma. Most of the recent studies are focused towards the identification of novel markers for cancer stem cells. The present review article is focused on two important markers in current research viz. Prominin-1 and NPM1 in glioblastoma.
Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/diagnóstico , Glioblastoma/diagnóstico , Células-Tronco Neoplásicas/metabolismo , Antígeno AC133/metabolismo , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Humanos , Células-Tronco Neoplásicas/patologia , Proteínas Nucleares/metabolismo , NucleofosminaRESUMO
Glycogenin-2 is one of two self-glucosylating proteins involved in the initiation phase of the synthesis of the storage polysaccharide glycogen. Cloning of the human glycogenin-2 gene, GYG2, has revealed the presence of 11 exons and a gene of more than 46 kb in size. The structure of the gene explains much of the observed diversity in glycogenin-2 cDNA sequences as being due to alternate exon usage. In some cases, there is variation in the splice junctions used. Over regions of protein sequence similarity, the GYG2 gene structure is similar to that of the other glycogenin gene, GYG. A genomic GYG2 clone was used to localize the gene to Xp22.3 by fluorescence in-situ hybridization. Localization close to the telomere of the short arm of the X chromosome is consistent with mapping information obtained from glycogenin-2 STS sequences. Glycogenin-2 maps between the microsatellite anchor markers AFM319te9 (DXS7100) and AFM205tf2 (DXS1060), and its 3' end is 34.5 kb from the 3' end of the arylsulphatase gene ARSD. GYG2 is outside the pseudoautosomal region PAR1 but still in a region of X-Y shared genes. As is true for several other genes in this location, an inactive remnant of GYG2, consisting of exons 1-3, may be present on the Y chromosome.
Assuntos
Genes/genética , Glicoproteínas/genética , Sequência de Aminoácidos , Mapeamento Cromossômico , Clonagem Molecular , DNA/química , DNA/genética , DNA Complementar/genética , Éxons , Glucosiltransferases , Humanos , Íntrons , Repetições de Microssatélites , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Cromossomo X/genéticaRESUMO
Cordyceps sinensis, a well-known traditional Chinese medicine, possesses activities in anti-tumour, anti-oxidation and stimulating the immune system; however, the identity of active component(s) is not determined. By using anti-oxidation activity-guided fractionation, a polysaccharide of molecular weight approximately 210 kDa was isolated from cultured Cordyceps mycelia by ion-exchange and sizing chromatography. The isolated polysaccharide, having strong anti-oxidation activity, contains glucose, mannose and galactose in a ratio of 1 : 0.6 : 0.75. The pre-treatment of isolated polysaccharide on the cultured rat pheochromocytoma PC12 cells shows strong protective effect against hydrogen peroxide (H(2)O(2))-induced insult. Treatment of the cells with the isolated polysaccharide at 100 microg/ml prior to H(2)O(2) exposure significantly elevated the survival of PC12 cells in culture by over 60%. In parallel, the H(2)O(2)-induced production of malondialdehyde in cultured cells was markedly reduced by the polysaccharide treatment. Moreover, the pre-treatment of the isolated polysaccharide significantly attenuated the changes of glutathione peroxidase and superoxide dismutase activities in H(2)O(2)-treated cells in a dose-dependent manner. This is the first report in identifying a polysaccharide from Cordyceps, which protects against the free radical-induced neuronal cell toxicity.
Assuntos
Cordyceps/química , Peróxido de Hidrogênio/toxicidade , Medicina Tradicional Chinesa , Polissacarídeos/farmacologia , Substâncias Protetoras/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Eletroforese Capilar , Glutationa Peroxidase/metabolismo , Malondialdeído/metabolismo , Células PC12 , Polissacarídeos/isolamento & purificação , Substâncias Protetoras/isolamento & purificação , Ratos , Superóxido Dismutase/metabolismoRESUMO
Radix Astragali (root of Astragalus; Huangqi) is a traditional Chinese medicine commonly used as an immunostimulant, hepatoprotective, diuretic, antidiabetic, analgesic, expectorant, and sedative drug. Although the species of Radix Astragali have been defined as Astragalus membranaceus and A. membranaceus var. mongholicus in Pharmacopoeia of China, their taxonomy remains controversial. The phylogenetic relationships among 10 Astragalus taxa, which are commonly found in China including A. membranaceus, A. membranaceus var. mongholicus, Astragalus propinquus, Astragalus lepsensis, Astragalus aksuensis, Astragalus hoantchy, Astragalus hoantchy subsp. dshimensis,Astragalus lehmannianus, Astragalus sieversianus, and Astragalus austrosibiricus, were determined using the DNA sequences of the 5S ribosomal RNA (5S rRNA) spacer, internal transcribed spacer region (ITS), and 18S rRNA coding region. The 5S rRNA spacer, ITS, and 18S rRNA, amplified by polymerase chain reaction from the isolated genomic DNAs, were sequenced. By using neighbor-joining and maximum parsimony analyses, phylogenetic trees were mapped by their sequence diversity. A. membranaceus and A. membranaceus var. mongholicus shared the greatest sequence homology. In addition, A. propinquus shared a closer relationship with A. membranaceus and A. membranaceus var. mongholicus, while other Astragalus species were less closely related. This is the first paper to show the phylogenetic relationship of Astragalus species related to Radix Astragali in China by the molecular genetic approach.
Assuntos
Astrágalo/genética , DNA de Plantas/química , DNA Espaçador Ribossômico/química , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 5S/genética , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de DNARESUMO
Root of Panax notoginseng (Radix Notoginseng, Sanqi) is a well-known traditional Chinese medicine and is mainly cultivated in Wenshan of Yunnan, China. The active constituents include saponin, dencichine, flavonoid, and polysaccharide; however, the levels of these components vary in different geographical regions of growth and also show a seasonal variation. By using high-performance liquid chromatography and spectrophotometry, the contents of notoginsenoside R1, ginsenoside R(g1), R(b1), R(d), dencichine, flavonoid, and polysaccharide were determined and compared with Radix Notoginseng collected from different regions of growth in China, as well as from different seasons of harvest and market grades. Using the contents of these active constituents as markers, the best quality of Radix Notoginseng is found in the southwestern parts of Wenshan, and the best season for the harvest is September to October. In addition, the unseeded plants produced a better quality of Radix Notoginseng. The current results provide useful information for the quality control of Radix Notoginseng and its further development in establishing the good agriculture practice standard of P. notoginseng in China.
Assuntos
Panax/química , Raízes de Plantas/química , Estações do Ano , Diamino Aminoácidos/análise , China , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Ginsenosídeos/análise , Polissacarídeos/análise , EspectrofotometriaRESUMO
The roots of Angelica sinensis (Danggui), a traditional Chinese medicine, have been used for invigorating blood circulation for over 2000 years in China. Three common species of Angelica roots are found in Asia: A. sinensis from China, A. acutiloba from Japan, and A. gigas from Korea. By using a molecular genetic approach, the 5S-rRNA spacer domains of the three species of Angelica were amplified, and their nucleotide sequences were determined. Diversity in DNA sequences among various species was found in their 5S-rRNA spacer domains, which could serve as markers for authentic identification of Angelica roots. In chemical analyses, the main constituents of Angelica roots including ferulic acid and Z-ligustilide were determined by HPLC; roots of A. sinensis were clearly distinct in that they contained approximately 10-fold higher levels of ferulic acid and Z-ligustilide as compared to roots of A. acutiloba and A. gigas. In addition, the amounts of main constituents in roots of A. sinensis varied according to different regions of cultivation and different methods of preservation. The chemical profile determined by HPLC therefore could serve as a fingerprint for quality control of Angelica roots.