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1.
Clin Biomech (Bristol, Avon) ; 80: 105108, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32736277

RESUMO

BACKGROUND: Cranial pia mater, the innermost layer of the meninges, protects the central nervous system by tightly wrapping the brain and damping the external impact force to the brain. Accurate experimental data of the mechanical property of the cranial pia mater can enhance the theoretical prediction of traumatic brain injury or the scientific surgery design for brain disease. The aim of this study is to characterize the mechanical behavior of the cranial pia mater. METHODS: In vitro tensile and stress-relaxation experiments of ovine cranial pia mater specimens were conducted at eight strain rates to characterize the rate-dependent viscoelastic property. The tensile and stress-relaxation experimental data were fitted by an Ogden hyper-viscoelastic model with a strain rate function to describe the mechanical behavior of the cranial pia mater. FINDINGS: The elastic modulus and the ultimate stress are significantly increased from 5.545 MPa and 0.535 MPa at 0.00167 s-1 to 18.345 MPa and 2.547 MPa at 0.83 s-1 (p < .0001), respectively. The initial stress and the long-term stress (300 s) are also increased significantly with the increasing strain rates (p < .0001). A good fit of the experimental data with the Ogden hyper-viscoelastic model incorporated with a strain rate function was achieved (R2 > 0.93). INTERPRETATION: The cranial pia mater exhibits as a rate-dependent hyper-viscoelastic material in the tensile and stress-relaxation experiments. Compared with the brain, the stiffer nature of the cranial pia mater indicates its essential role in brain protection. The rate-dependent constitutive model provides a proper description of the hyper-viscoelastic characteristics of the cranial pia mater in tension and may provide a basic constitutive relationship for numerical simulations of traumatic brain injury.


Assuntos
Módulo de Elasticidade , Pia-Máter/fisiologia , Estresse Mecânico , Animais , Fenômenos Biomecânicos , Humanos , Ovinos , Viscosidade
2.
Curr Oncol ; 27(3): e259-e264, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32669931

RESUMO

Background: Gastric stump ("remnant") cancer is the development of a malignancy related to previous gastric surgery. Prognosis in gastric stump cancer, compared with that in primary gastric cancer, is still controversial. Methods: From January 1988 to December 2012 at a single medical centre in Taiwan, 105 patients with gastric stump cancer, including 85 with previous peptic ulcer disease and 20 with previous gastric cancer, were analyzed for clinicopathologic characteristics and overall survival (os). Results: The 5-year os rates for patients with gastric stump cancer and with primary gastric cancer were 51.2% and 54.5% respectively (p = 0.035). Analysis of clinicopathologic characteristics indicated that, compared with patients having primary gastric cancer, those with gastric stump cancer had more lymph node metastasis (p < 0.001) and had been diagnosed at a more advanced stage (p = 0.047). Multivariate analysis with os as an endpoint showed that age [p = 0.015; hazard ratio (hr): 2.300; 95% confidence interval (ci): 1.173 to 4.509], tumour size (p = 0.037; hr: 1.700; 95% ci: 1.031 to 2.801), stromal reaction (p = 0.021; hr: 1.802; 95% ci: 1.094 to 2.969), and pathologic N category (p = 0.001; hr: 1.449; 95% ci: 1.161 to 1.807) were independent predictors in gastric stump cancer. The os rates for patients with gastric stump cancer who previously had gastric cancer or peptic ulcer disease were 72.9% and 50.0% respectively (p = 0.019). The Borrmann classification was more superficial (p = 0.005), lymph node metastases were fewer (p = 0.004), and staging was less advanced (p = 0.025) in patients with gastric stump cancer who previously had gastric cancer than in their counterparts who previously had peptic ulcer disease. Conclusions: Survival is poorer in patients with gastric stump cancer who previously had peptic ulcer disease than in those who previously had primary gastric cancer. Patients with gastric stump cancer who previously had gastric cancer and could receive curative gastrectomy tended to have a better prognosis because of a more superficial Borrmann classification. Regular follow-up in patients who have undergone gastric surgery is recommended for the early detection of gastric stump cancer.


Assuntos
Coto Gástrico/fisiopatologia , Neoplasias Gástricas/complicações , Neoplasias Gástricas/cirurgia , Idoso , Feminino , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Análise de Sobrevida
3.
Clin Otolaryngol ; 43(4): 1065-1072, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29575557

RESUMO

OBJECTIVES: Ultrasound-guided aspiration cytology (US-FNAC) was previously used to diagnose lymph node metastasis of papillary thyroid carcinoma (PTC). Combined US-FNAC with nodal thyroglobulin (LN-FNA-Tg) significantly improved the diagnostic rate. However, diagnostic accuracy depends on proper node selection. Therefore, it is crucial to choose the nodes with reliable sonographic features to guide clinician for confirmation. DESIGN AND SETTING: Retrospective cohort study was carried out in one medical centre from 2011 to 2014. PARTICIPANTS: A total of 148 patients with PTC, being treated by total thyroidectomy and radioiodine, were assessed for potential nodal metastases by ultrasound. MAIN OUTCOME MEASURES: Lymph nodes with cystic content, peripheral hypervascularity, calcification, hyperechoic content, the absence of hilum and Solbiati index < 2 indicated risk of malignancy. US-FNAC and LN-FNA-Tg were both performed. Positive nodal metastasis was further confirmed by dissection. Risk impact of these sonographic features on LN-FNA-Tg to diagnose nodal metastasis was tested by logistic regression analysis based on the significance in both univariate and multivariate models. RESULTS: Overall, 49 lymph nodes were documented as recurrent nodal metastasis. LN-FNA-Tg greater than serum thyroglobulin and higher than 1 ng/mL achieved 100% of diagnostic rate for recurrent nodal metastasis. The malignant sonographic features that significantly cohered with positive LN-FNA-Tg were cystic and hyperechoic content and lack hilum, in sequence. CONCLUSIONS: LN-FNA-Tg is an excellent tool to quantitatively diagnose nodal metastasis. To achieve ideal diagnosis, the most reliable sonographic features were cystic content, hyperechoic content and the absence of hilum in lymph nodes, but not calcification or Solbiati index < 2.

4.
J Appl Microbiol ; 123(3): 594-601, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28688204

RESUMO

AIMS: The purpose of this study was to produce a recombinant pseudorabies virus (PRV) glycoprotein E (gE) protein with the correct antigenicity for use as a low-cost diagnostic antigen. METHODS AND RESULTS: The gene fragment encoding the amino-terminal immunodominant region of PRV gE (codons 31-270) (gEN31-270) was codon optimized and expressed constitutively and secreted using a Pichia pastoris expression system. Yeast-expressed gEN31-270 (ygEN31-270) was harvested from the culture supernatant, and ygEN31-270 was shown to exhibit N-linked glycosylation. An indirect sandwich enzyme-linked immunosorbent assay (ELISA) was developed using ygEN31-270 as a coating antigen, and the results showed that the assay had high sensitivity and specificity, as well as almost perfect concordance with a commercial gE ELISA kit. CONCLUSIONS: The immunodominant region (amino acids 31-270) of gE was expressed successfully in P. pastoris using a codon optimization strategy. ygEN31-270 was secreted and N-glycosylated. The ygEN31-270-based indirect sandwich ELISA showed high sensitivity and specificity to detect gE-specific antibodies in swine serum samples. SIGNIFICANCE AND IMPACT OF THE STUDY: The ygEN31-270-based indirect sandwich ELISA may provide an alternative method for developing a diagnostic kit with easy manipulation and low cost.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Herpesvirus Suídeo 1/isolamento & purificação , Pichia/genética , Pseudorraiva/diagnóstico , Proteínas do Envelope Viral/análise , Animais , Anticorpos Antivirais/análise , Anticorpos Antivirais/sangue , Glicosilação , Herpesvirus Suídeo 1/genética , Herpesvirus Suídeo 1/imunologia , Pichia/metabolismo , Pseudorraiva/sangue , Pseudorraiva/virologia , Proteínas Recombinantes/análise , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade , Suínos , Proteínas do Envelope Viral/classificação , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia
5.
Oncogene ; 36(21): 2946-2956, 2017 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-28092674

RESUMO

Aberrant epidermal growth factor (EGF) receptor (EGFR) signaling contributes to neoplastic initiation and progression in lung. Mutated EGFR has become as an important therapeutic target in lung cancer, whereas targeted treatment is not available for wild-type EGFR or its ligands. In this study, we found that heparin-binding (HB)-EGF, a member of the EGF family, was highly expressed in a subset of lung cancer, proliferation of which was dependent on HB-EGF signaling. Silencing of HB-EGF with RNA interference inhibited cell cycle progression in lung cancer cells. We observed that, upon HB-EGF induction, CITED4 was induced through a signal transducer and activator of transcription 3 (STAT3)-dependent pathway, regulating cell proliferation. CITED4 interacted with MYC and potentiated MYC-mediated transactivation of the CCND1 promoter, leading to cell cycle progression. Correlation analysis revealed that HB-EGF and CITED4 were significantly positively associated in primary lung tumors, and expression of HB-EGF predicted a poor survival outcome in patients. In vitro and in vivo experiments revealed that pharmacological inhibition of HB-EGF with CRM197 significantly attenuated tumor cell growth. Thus, CITED4 functions as a molecular switch in HB-EGF-induced growth control, and HB-EGF provides a novel therapeutic target for lung cancer intervention.


Assuntos
Carcinogênese/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Fator de Crescimento Semelhante a EGF de Ligação à Heparina/fisiologia , Neoplasias Pulmonares/genética , Fatores de Transcrição/fisiologia , Células A549 , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinogênese/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Fator de Crescimento Semelhante a EGF de Ligação à Heparina/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Terapia de Alvo Molecular , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Compr Psychiatry ; 62: 80-5, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26343470

RESUMO

OBJECTIVES: Psychotic symptoms are commonly observed among heroin users. Low serum brain-derived neurotrophic factor (BDNF) levels have been reported in schizophrenia and psychosis; however, studies assessing the relationship between serum BDNF levels and psychotic symptoms in heroin dependence are lacking. METHOD: A total of 31 heroin-dependent patients who had never experienced psychotic symptoms during heroin consumption and 21 patients with a history of psychotic symptoms were consecutively recruited. We measured by enzyme-linked immunosorbent assay (ELISA) serum BDNF levels during early abstinence. A gender- and age-matched sample of healthy controls was also recruited and underwent measurement of BDNF. RESULTS: BDNF levels were significantly lower in patients with psychotic symptoms than in those without psychotic symptoms (P<0.001). BDNF levels were not found to be correlated with sex, age, age of onset, duration of heroin use, average daily dose of heroin use, frequency of heroin use, SDS scores, BAI scores and BDI scores in the psychotic subsamples (all P>0.05). CONCLUSIONS: Our findings suggest that heroin-dependent patients with psychotic symptoms share some of the neurotrophic insult that characterizes schizophrenia and psychosis.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/sangue , Dependência de Heroína/sangue , Dependência de Heroína/psicologia , Transtornos Psicóticos/sangue , Transtornos Psicóticos/complicações , Adulto , Estudos de Casos e Controles , Feminino , Dependência de Heroína/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/psicologia
7.
Oncogene ; 34(29): 3791-803, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25263444

RESUMO

Epidermal growth factor receptor (EGFR) regulates multiple signaling cascades essential for cell proliferation, growth and differentiation. Using a genetic approach, we found that Drosophila FERM and PDZ domain-containing protein tyrosine phosphatase, dPtpmeg, negatively regulates border cell migration and inhibits the EGFR/Ras/mitogen-activated protein kinase signaling pathway during wing morphogenesis. We further identified EGFR pathway substrate 15 (Eps15) as a target of dPtpmeg and its human homolog PTPN3. Eps15 is a scaffolding adaptor protein known to be involved in EGFR endocytosis and trafficking. Interestingly, PTPN3-mediated tyrosine dephosphorylation of Eps15 promotes EGFR for lipid raft-mediated endocytosis and lysosomal degradation. PTPN3 and the Eps15 tyrosine phosphorylation-deficient mutant suppress non-small-cell lung cancer cell growth and migration in vitro and reduce lung tumor xenograft growth in vivo. Moreover, depletion of PTPN3 impairs the degradation of EGFR and enhances proliferation and tumorigenicity of lung cancer cells. Taken together, these results indicate that PTPN3 may act as a tumor suppressor in lung cancer through its modulation of EGFR signaling.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Movimento Celular , Proliferação de Células , Receptores ErbB/metabolismo , Neoplasias Pulmonares/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 3/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Animais Geneticamente Modificados , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular , Linhagem Celular Tumoral , Endocitose , Feminino , Células HEK293 , Humanos , Immunoblotting , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Microdomínios da Membrana/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia Confocal , Mutação , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 3/genética , Interferência de RNA , Transplante Heterólogo
8.
Br J Cancer ; 111(9): 1765-71, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25233396

RESUMO

BACKGROUND: The detection of microRNA (miRNA) dysregulation in stool is a novel approach for the diagnosis of colorectal carcinoma (CRC). The aim of this study is to investigate the use of miR-221 and miR-18a in stool samples as non-invasive biomarkers for CRC diagnosis. METHODS: A miRNA expression array containing 667 miRNAs was performed to identify miRNA dysregulation in CRC tissues. We focused on miR-221 and miR-18a, two significantly upregulated miRNAs which were subsequently verified in 40 pairs of CRC tissues and 595 stool samples (198 CRCs, 199 polyps and 198 normal controls). RESULTS: miR-221 and miR-18a were upregulated in the miRNA expression array. miR-221 and miR-18a levels were also significantly higher in 40 CRC tumours compared with their respective adjacent normal tissues. In stool samples, miR-221 and miR-18a showed a significant increasing trend from normal controls to late stages of CRC (P<0.0001). The levels of stool miR-221 and miR-18a were both significantly higher in subjects with stages I+II (miR-221: P<0.0001, miR-18a: P<0.0001) and stages III+IV of CRC (miR-221: P=0.0004, miR-18a: P<0.0001) compared with normal controls. The AUC of stool miR-221 and miR-18a were 0.73 and 0.67 for CRC patients as compared with normal controls, respectively. No significant differences in stool miR-221 and miR-18a levels were found between patients with proximal and distal CRCs. The use of antibiotics did not influence stool miRNA-221 and miRNA-18a levels. CONCLUSIONS: Stool-based miR-221 can be used as a non-invasive biomarker for the detection of CRC.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Fezes/química , MicroRNAs/genética , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Curva ROC
9.
J Virol ; 88(18): 10662-72, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24991008

RESUMO

UNLABELLED: Undifferentiated nasopharyngeal carcinoma (NPC) has a 100% association with Epstein-Barr virus (EBV). However, only three EBV genomes isolated from NPC patients have been sequenced to date, and the role of EBV genomic variations in the pathogenesis of NPC is unclear. We sought to obtain the sequences of EBV genomes in multiple NPC biopsy specimens in the same geographic location in order to reveal their sequence diversity. Three published EBV (B95-8, C666-1, and HKNPC1) genomes were first resequenced using the sequencing workflow of target enrichment of EBV DNA by hybridization, followed by next-generation sequencing, de novo assembly, and joining of contigs by Sanger sequencing. The sequences of eight NPC biopsy specimen-derived EBV (NPC-EBV) genomes, designated HKNPC2 to HKNPC9, were then determined. They harbored 1,736 variations in total, including 1,601 substitutions, 64 insertions, and 71 deletions, compared to the reference EBV. Furthermore, genes encoding latent, early lytic, and tegument proteins and glycoproteins were found to contain nonsynonymous mutations of potential biological significance. Phylogenetic analysis showed that the HKNPC6 and -7 genomes, which were isolated from tumor biopsy specimens of advanced metastatic NPC cases, were distinct from the other six NPC-EBV genomes, suggesting the presence of at least two parental lineages of EBV among the NPC-EBV genomes. In conclusion, much greater sequence diversity among EBV isolates derived from NPC biopsy specimens is demonstrated on a whole-genome level through a complete sequencing workflow. Large-scale sequencing and comparison of EBV genomes isolated from NPC and normal subjects should be performed to assess whether EBV genomic variations contribute to NPC pathogenesis. IMPORTANCE: This study established a sequencing workflow from EBV DNA capture and sequencing to de novo assembly and contig joining. We reported eight newly sequenced EBV genomes isolated from primary NPC biopsy specimens and revealed the sequence diversity on a whole-genome level among these EBV isolates. At least two lineages of EBV strains are observed, and recombination among these lineages is inferred. Our study has demonstrated the value of, and provided a platform for, genome sequencing of EBV.


Assuntos
Variação Genética , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Neoplasias Nasofaríngeas/virologia , Adulto , Sequência de Bases , Biópsia , Carcinoma , Feminino , Genoma Viral , Herpesvirus Humano 4/classificação , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutagênese Insercional , Carcinoma Nasofaríngeo , Filogenia , Deleção de Sequência , Adulto Jovem
10.
Braz. j. med. biol. res ; 46(1): 1-13, 11/jan. 2013. graf
Artigo em Inglês | LILACS | ID: lil-665794

RESUMO

An important disease among human metabolic disorders is type 2 diabetes mellitus. This disorder involves multiple physiological defects that result from high blood glucose content and eventually lead to the onset of insulin resistance. The combination of insulin resistance, increased glucose production, and decreased insulin secretion creates a diabetic metabolic environment that leads to a lifetime of management. Appropriate models are critical for the success of research. As such, a unique model providing insight into the mechanisms of reversible insulin resistance is mammalian hibernation. Hibernators, such as ground squirrels and bats, are excellent examples of animals exhibiting reversible insulin resistance, for which a rapid increase in body weight is required prior to entry into dormancy. Hibernator studies have shown differential regulation of specific molecular pathways involved in reversible resistance to insulin. The present review focuses on this growing area of research and the molecular mechanisms that regulate glucose homeostasis, and explores the roles of the Akt signaling pathway during hibernation. Here, we propose a link between hibernation, a well-documented response to periods of environmental stress, and reversible insulin resistance, potentially facilitated by key alterations in the Akt signaling network, PPAR-γ/PGC-1α regulation, and non-coding RNA expression. Coincidentally, many of the same pathways are frequently found to be dysregulated during insulin resistance in human type 2 diabetes. Hence, the molecular networks that may regulate reversible insulin resistance in hibernating mammals represent a novel approach by providing insight into medical treatment of insulin resistance in humans.


Assuntos
Animais , Diabetes Mellitus Experimental/fisiopatologia , Hibernação/fisiologia , Resistência à Insulina/fisiologia , Sciuridae/metabolismo , Diabetes Mellitus Experimental/metabolismo , /metabolismo , /fisiopatologia , Glucose/metabolismo , Hibernação/genética , Resistência à Insulina/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Obesidade/genética , Obesidade/metabolismo , Obesidade/fisiopatologia , Biossíntese de Proteínas/genética , Sciuridae/fisiologia , Transdução de Sinais/genética
11.
Oncogene ; 32(42): 5078-88, 2013 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-23208495

RESUMO

Using microRNA (miRNA) expression array, we identified that miR-7 was deregulated in colorectal cancer (CRC). We studied the biological role and molecular target of miR-7 in CRC. miR-7 was downregulated in six out of seven colon cancer cell lines. Ectopic expression of miR-7 suppressed colon cancer cell proliferation (P<0.05), induced apoptosis (P<0.05) and caused cell-cycle arrest in G1 phase (P<0.05). The tumor suppressive function of miR-7 was further confirmed in nude mice (P<0.05). The 3'-untranslated region (3'UTR) of Yin Yang 1 (YY1) mRNA contains an evolutionarily conserved miR-7 binding site using in silico searches, luciferase reporter assay and western blot analysis confirmed that miR-7 directly bound to YY1 3'UTR to negatively regulate the protein expression of YY1 in colon cancer cell lines HCT116 and LOVO. Intriguingly, knock-down of YY1 in three colon cancer cell lines (HCT116, LOVO and DLD1) consistently suppressed cell proliferation (P<0.01) and induced apoptosis (P<0.01), indicating the opposite functions of miR-7 and YY1 in CRC. Consistent with these data, ectopic expression of YY1 promoted cell growth by increasing proliferation (P<0.01) and suppressing apoptosis (P<0.001). The tumorigenic ability of YY1 was further confirmed in vivo in xenograft-nude mouse model (P<0.01). In addition, pathway analyses revealed that the oncogenic effect by YY1 was associated with inhibiting p53 and modulating its downstream effectors p15, caspase cascades and C-Jun, and activating Wnt signaling pathway through activating ß-catenin, anti-apoptotic survivin and fibroblast growth factor 4. Furthermore, multivariate analysis revealed that patients with YY1 protein high expression had a significant decrease in overall survival, and Kaplan-Meier survival curves showed that these patients had significantly shorter survival than others (P<0.0001). In conclusion, MiR-7 is a novel miRNA with tumor suppressive function in colon cancer by targeting oncogenic YY1. YY1 promotes colon cancer growth through inhibiting p53 and promoting Wnt signaling pathways and serves as an independent prognostic biomarker for CRC patients.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , MicroRNAs/genética , Fator de Transcrição YY1/genética , Regiões 3' não Traduzidas , Animais , Apoptose/genética , Biomarcadores Tumorais , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/mortalidade , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Genes p53 , Células HCT116 , Humanos , Estimativa de Kaplan-Meier , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Via de Sinalização Wnt , Ensaios Antitumorais Modelo de Xenoenxerto , Fator de Transcrição YY1/metabolismo , beta Catenina/metabolismo
12.
Cell Death Differ ; 19(12): 2015-28, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22814619

RESUMO

Transforming growth factor-α (TGF-α)-induced proliferation and transforming growth factor-ß (TGF-ß)-mediated quiescence are intricately balanced in normal lung-tissue homeostasis but are deregulated during neoplastic progression of lung cancer. Here, we show that Cbp/p300-interacting transactivator with Glu/Asp-rich carboxy-terminal domain 2 (CITED2), a novel MYC-interacting transcriptional modulator, responds to TGF-α induction and TGF-ß suppression to orchestrate cellular proliferation and quiescence, respectively. Upon TGF-α induction, CITED2 was induced by MYC and further modulated MYC-mediated transcription in a feed-forward manner. CITED2 recruited p300 to promote MYC-p300-mediated transactivation of E2F3, leading to increased G1/S cell cycle progression. Moreover, CITED2 inhibited cellular quiescence by enhancing MYC-mediated suppression of p21(CIP1). CITED2 interacted with histone deacetylase 1 (HDAC1) and potentiated MYC-HDAC1 complex formation. TGF-ß stimulation provoked downregulation of CITED2, which abrogated MYC-HDAC1-mediated p21(CIP1) suppression, causing cellular quiescence. Ectopic CITED2 expression enhanced tumor growth in nude mice; furthermore, CITED2 knockdown caused tumor shrinkage and increased overall host mouse survival rates. Expression of CITED2/MYC/E2F3/p21(CIP1) signaling molecules was associated with poor prognosis of lung cancer patients. Thus, CITED2 functions as a molecular switch of TGF-α and TGF-ß-induced growth control, and MYC-CITED2 signaling axis provides a new index for predicting clinical outcome.


Assuntos
Proteínas Repressoras/metabolismo , Transativadores/metabolismo , Fator de Crescimento Transformador alfa/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Senescência Celular , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação para Baixo , Fatores de Transcrição E2F/metabolismo , Receptores ErbB/metabolismo , Histona Desacetilase 1/metabolismo , Humanos , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transdução de Sinais , Ativação Transcricional , Transplante Heterólogo
13.
Br J Cancer ; 106(9): 1486-94, 2012 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-22472882

RESUMO

BACKGROUND: We have previously demonstrated that peroxisome proliferator-activated receptor (PPARγ) activation inhibits hepatocarcinogenesis. We aim to investigate the effect of PPARγ on hepatocellular carcinoma (HCC) metastatic potential and explore its underlying mechanisms. METHODS: Human HCC cells (MHCC97L, BEL-7404) were infected with adenovirus-expressing PPARγ (Ad-PPARγ) or Ad-lacZ and treated with or without PPARγ agonist (rosiglitazone). The effects of PPARγ on cell migration and invasive activity were determined by wound healing assay and Matrigel invasive model in vitro, and in an orthotopic liver tumour metastatic model in mice. RESULTS: Pronounced expression of PPARγ was demonstrated in HCC cells (MHCC97L, BEL-7404) treated with Ad-PPARγ, rosiglitazone or Ad-PPARγ plus rosiglitazone, compared with control (Ad-LacZ). Such induction markedly suppressed HCC cell migration. Moreover, the invasiveness of MHCC97L and BEL-7404 cells infected with Ad-PPARγ, or treated with rosiglitazone was significantly diminished up to 60%. Combination of Ad-PPARγ and rosiglitazone showed an additive effect. Activation of PPARγ by rosiglitazone significantly reduced the incidence and severity of lung metastasis in an orthotopic HCC mouse model. Key mechanisms underlying the effect of PPARγ in HCC include upregulation of cell adhesion genes, E-cadherin and SYK (spleen tyrosine kinase), extracellular matrix regulator tissue inhibitors of metalloproteinase (TIMP) 3, tumour suppressor gene retinoblastoma 1, and downregulation of pro-metastatic genes MMP9 (matrix metallopeptidase 9), MMP13, HPSE (heparanase), and Hepatocyte growth factor (HGF). Direct transcriptional regulation of TIMP3, MMP9, MMP13, and HPSE by PPARγ was shown by ChIP-PCR. CONCLUSION: Peroxisome proliferator-activated receptor-gamma exerts an inhibitory effect on the invasive and metastatic potential of HCC in vitro and in vivo, and is thus, a target for the prevention and treatment of HCC metastases.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , PPAR gama/agonistas , PPAR gama/metabolismo , Tiazolidinedionas/farmacologia , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Caderinas , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Imunoprecipitação da Cromatina , Perfilação da Expressão Gênica , Humanos , Hipoglicemiantes/farmacologia , Técnicas In Vitro , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Rosiglitazona , Células Tumorais Cultivadas
14.
Surg Endosc ; 26(9): 2601-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22476838

RESUMO

INTRODUCTION: The objective of the study was to assess the mechanism of recurrent laryngeal nerve (RLN) injury during video-assisted thyroidectomy (VAT). METHODS: The study examined 201 nerves at risk (NAR). VAT with laryngeal neuromonitoring (LNM) was outlined according to this scheme: (a) preparation of the operative space; (b) vagal nerve stimulation (V1); (c) ligature of the superior thyroid vessels; (d) visualization, stimulation (R1), and dissection of the RLN; (e) extraction of the lobe; (f) resection of the thyroid lobe; (g) final hemostasis; (h) verification of the electrical integrity of the RLN (V2, R2). The site, cause, and circumstance of nerve injury were elucidated with the application of LNM. Laryngeal nerve injuries were classified into type 1 injury (segmental) and 2 (diffuse). RESULTS: Fourteen nerves (6.9 %) experienced loss of R2 and V2 signals. 80 percent of lesions occurred in the distal 1 cm of the course of the RLN. The incidence of type 1 and 2 injuries was 71 and 29 % respectively. The mechanisms of injury were traction (70 %) and thermal (30 %). Traction lesions were created during the extraction of the lobe from the mini-incision [point (e)]. Thermal injury occurred during energy-based device use in (f) and (g) circumstances. CONCLUSIONS: RLN palsy still occurs with routine endoscopic identification of the nerve, even combined with LNM. LNM has the advantage of elucidating the mechanism of RLN injury. Traction and thermal RLN injuries are the most frequent lesions in VAT.


Assuntos
Monitorização Intraoperatória , Traumatismos do Nervo Laríngeo Recorrente/etiologia , Traumatismos do Nervo Laríngeo Recorrente/prevenção & controle , Tireoidectomia/efeitos adversos , Tireoidectomia/métodos , Cirurgia Vídeoassistida , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
15.
Oncogene ; 31(2): 226-37, 2012 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-21666718

RESUMO

MicroRNAs (miRNAs) are endogenous non-coding RNAs that are known to be involved in the pathogenesis of tumors. Gastric carcinoma (GC) is a common malignancy worldwide. The aim of this study was the identification of the expression signature and functional roles of aberrant miRNAs in GC. Initial screening established a profile of aberrantly expressed miRNAs in tumors. miR-370 was confirmed to be overexpressed in GC tissues. Higher expression of miR-370 in GC tissues was associated with more advanced nodal metastasis and a higher clinical stage compared with controls. In addition, significantly higher level of miR-370 was noted in the plasma of GC patients compared with controls. Patients having more invasive or advanced tumors also exhibited a higher plasma level of miR-370. In vitro assays indicated that exogenous miR-370 expression enhanced the oncogenic potential of GC cells. The AGS-GFPM2 cells with exogenous miR-370 expression also exhibited enhanced abdominal metastatic dissemination in nude mice. Reporter assays confirmed that miR-370 targeted predicted sites in 3'UTR of transforming growth factor-ß receptor II (TGFß-RII) gene. The exogenous miR-370 expression decreased TGFß-RII expression and the phosphorylation of Smad3 elicited by TGFß1. The TGFß1-mediated repression in cell migration was reverted by exogenous miR-370 expression. A reverse correlation between miR-370 and TGFß-RII expression was noted in GC tissues. This study concludes that miR-370 is a miRNA that is associated with GC progression by downregulating TGFß-RII. The miRNA expression profile described in this study should contribute to future studies on the role of miRNAs in GC.


Assuntos
MicroRNAs/genética , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Neoplasias Gástricas/genética , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Receptor do Fator de Crescimento Transformador beta Tipo II , Neoplasias Gástricas/patologia
17.
Genet Mol Res ; 10(2): 576-87, 2011 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-21491368

RESUMO

The QM-like gene encodes a ribosomal protein L10. Besides housekeeping roles in protein synthesis, QM-like proteins have multiple extraribosomal functions during cell growth, cell differentiation and apoptosis. We obtained the full-length cDNA of QM-like protein (designated as SoQM) from the salt water game fish Sciaenops ocellatus, using RACE-PCR. The sequence consists of 740 bp, encoding 215-amino acid residues with 24.60 kDa. The AA sequence of the SoQM protein contains a series of functional motifs that belong to the QM family signature, which is conserved among different species. The SoQM gene contains five introns and six exons. The expression pattern of SoQM as determined by RT-PCR indicated that SoQM mRNA was expressed in all tissues tested, including brain, gill, head-kidney, intestine, stomach, heart, spleen, blood, muscle, and gonads. The phylogenetic tree constructed with MEGA 4.0 showed that SoQM clusters together with that of other fish. It was found that the sequences of the SoQM gene are highly conserved, suggesting the fundamental and critical functions of SoQM in S. ocellatus. The three-dimensional structure of the SoQM protein core domain (4~169) was predicted by the Swiss-Model program. Compared with QM proteins in other species, the main structure of SoQM protein was conserved, while the C-terminal domain was different from other QM-like proteins. Prediction of the three-dimensional structure of SoQM would provide valuable insight into the molecular basis of protein function, allowing an effective design of experiments, such as site-directed mutagenesis, studies of disease-related mutations or structure-based design of specific inhibitors.


Assuntos
Perciformes/genética , Proteínas Ribossômicas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Análise Citogenética , DNA Complementar/genética , Perfilação da Expressão Gênica , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Estrutura Secundária de Proteína , Proteína Ribossômica L10 , Alinhamento de Sequência , Análise de Sequência de DNA
18.
Br J Cancer ; 104(6): 893-8, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21364594

RESUMO

Recent researches have shed light on the biological importance of microRNAs (miRNAs) in colorectal cancer (CRC) genesis, progression and response to treatments. The potential utility of miRNAs in the preclinical stage have been explored and investigated. In this review, we explored the literature and reviewed the cutting edge progress in the discovery of noninvasive plasma and faecal miRNAs for CRC early diagnosis, as well as their measurability and predictability. We also discussed the utility of miRNAs as novel prognostic and predictive markers, and their association with CRC clinical phenotypes including recurrence, metastasis and therapeutic outcomes. Finally, we summarised miRNA-related single-nucleotide polymorphisms and their potential influence on sporadic CRC susceptibility and therapeutic response. In conclusion, the use of miRNAs as biomarker for CRC is still in its infancy and need further characterisation and evaluation.


Assuntos
Carcinoma/diagnóstico , Carcinoma/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Detecção Precoce de Câncer/métodos , MicroRNAs/genética , Biomarcadores Tumorais/genética , Carcinoma/sangue , Carcinoma/terapia , Neoplasias Colorretais/sangue , Neoplasias Colorretais/terapia , Fezes/química , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/análise , MicroRNAs/sangue , Polimorfismo Genético/fisiologia , Prognóstico , Resultado do Tratamento
19.
Oncogene ; 29(49): 6464-74, 2010 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-20802524

RESUMO

T-box transcription factor 5 (TBX5) is a member of a phylogenetically conserved family of genes involved in the regulation of developmental processes. The function of TBX5 in cancer development is largely unclear. We identified that TBX5 was preferentially methylated in cancer using methylation-sensitive arbitrarily primed PCR. We aim to clarify the epigenetic inactivation, biological function and clinical significance of TBX5 in colon cancer. Promoter methylation was evaluated by combined bisulfite restriction analysis and bisulfite genomic sequencing. Cell proliferation was examined by cell viability assay and colony formation assay, apoptosis by flow cytometry and cell migration by wound-healing assay. TBX5 target genes were identified by cDNA microarray analysis. Cox regression model and log-rank test were used to identify independent predictors of prognosis. TBX5 was silenced or downregulated in 88% (7/8) colon cancer cell lines, but was expressed in normal colon tissues. Loss of gene expression was associated with promoter methylation. The biological function of TBX5 in human colon cancer cells was examined. Re-expression of TBX5 in silenced colon cancer cell lines suppressed colony formation (P<0.001), proliferation (P<0.001), migration and induced apoptosis (P<0.01). Induction of apoptosis was mediated through cross-talk of extrinsic apoptosis pathway, apoptotic BCL2-associated X protein and Granzyme A signaling cascades. TBX5 suppressed tumor cell proliferation and metastasis through the upregulation of cyclin-dependent kinase inhibitor 2A, metastasis suppressor 1 and downregulation of synuclein gamma and metastasis-associated protein 1 family member 2. TBX5 methylation was detected in 68% (71/105) of primary colon tumors. Multivariate analysis showed that patients with TBX5 methylation had a significantly poor overall survival (P=0.0007). In conclusion, we identified a novel functional tumor suppressor gene TBX5 inactivated by promoter methylation in colon cancer. Detection of methylated TBX5 may serve as a potential biomarker for the prognosis of this malignancy.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias do Colo/genética , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Genes Supressores de Tumor , Proteínas com Domínio T/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Sobrevivência Celular/genética , Neoplasias do Colo/mortalidade , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Regulação para Baixo , Feminino , Granzimas/metabolismo , Histona Desacetilases/metabolismo , Humanos , Masculino , Proteínas dos Microfilamentos/metabolismo , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Regiões Promotoras Genéticas , Proteínas Repressoras/metabolismo , Transativadores , Proteína X Associada a bcl-2/metabolismo , gama-Sinucleína/metabolismo
20.
Gene Ther ; 17(6): 790-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20376096

RESUMO

Peroxisome proliferator-activated receptor-gamma (PPARgamma) is a transcription factor that regulates lipid metabolism and inflammatory responses. Certain PPARgamma ligands improve nonalcoholic steatohepatitis (NASH). The role of PPARgamma itself in NASH remains poorly understood. The functional consequences of PPARgamma in the development of steatohepatitis through gene deficiency or gene overexpression of PPARgamma delivered by adenovirus (Ad-PPARgamma) were examined. Our results show that PPARgamma-deficient (PPARgamma(+/-)) mice fed the methionine- and choline-deficient (MCD) diet developed more severe steatohepatitis than wild-type mice, and were unaffected by PPARgamma ligand rosiglitazone. Overexpression of PPARgamma delivered by Ad-PPARgamma attenuated steatohepatitis. This effect was associated with redistribution of fatty acid from liver to adipose tissue by enhancing expression of fatty acid uptake genes (fatty acid binding protein-4 (aP2), fatty acid translocase (CD36), lipoprotein lipase (LPL) and fatty acid transport protein-1 (FATP-1)) and lipogenic genes (sterol regulatory element binding protein isoform-1 (SREBP-1) and stearoyl-CoA desaturase isoform-1 (SCD-1)) in adipose tissue and to a lesser extent in liver. The anti-steatohepatitis action of PPARgamma was also mediated via regulating adipokines through suppressing tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) and inducing adiponectin. Moreover, PPARgamma activation suppressed hepatic lipoperoxide and reduced hepatic pro-inflammatory cytokines (TNF-alpha and IL-6) production. In conclusion, PPARgamma is an important endogenous regulator and potential therapeutic target for nutritional steatohepatitis.


Assuntos
Fígado Gorduroso/prevenção & controle , PPAR gama/metabolismo , Adenoviridae/genética , Animais , Deficiência de Colina , Fígado Gorduroso/etiologia , Fígado Gorduroso/genética , Técnicas de Transferência de Genes , Terapia Genética , Metionina/deficiência , Camundongos , PPAR gama/deficiência , PPAR gama/genética , Rosiglitazona , Tiazolidinedionas/farmacologia
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