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1.
J Med Virol ; 85(9): 1567-76, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23852681

RESUMO

The associations between variants of human papillomavirus (HPV) 16 and risk of cervical neoplasia have been reported, but nucleotide variations of HPV 16 in Asian populations and their association with cervical neoplasia have not been evaluated extensively. During 1991-1992, 11,923 women from seven townships in Taiwan were enrolled. The HPV DNA in cervical cells was detected and genotyped using EasyChip HPV blot. Nucleotide variations in the long control region (LCR), E6, and E7 genes were determined using DNA sequencing for 170 HPV 16-positive cervical samples. The Asian variant was the most prevalent variant (81.8%) of HPV 16 in Taiwan, and was also associated with increased prevalence of histologically confirmed cervical intraepithelial neoplasia grade 3 or worse, showing an age-adjusted odds ratio (exact confidence limits) of 10.70 (1.62-451.05; P = 0.0049) compared to the HPV 16 European variant. Similar significant associations with cervical intraepithelial neoplasia grade 3 or worse were also observed for distinct nucleotide substitutions, including T178A/G, A647G, A7730C/G, T7781C, G7842A, and C24T/G. These results demonstrate that non-European variants (non-E) of HPV 16, predominantly Asian variants, are associated with increased risk for severe cervical neoplasia, compared with European variants. Molecular mechanisms accounting for varied cervical neoplasia risk among different HPV 16 variants warrant further investigation.


Assuntos
Variação Genética , Papillomavirus Humano 16/classificação , Papillomavirus Humano 16/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/virologia , Adulto , Idoso , DNA Viral/química , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Genótipo , Papillomavirus Humano 16/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Epidemiologia Molecular , Dados de Sequência Molecular , Proteínas Oncogênicas Virais/genética , Proteínas E7 de Papillomavirus/genética , Infecções por Papillomavirus/epidemiologia , Mutação Puntual , Proteínas Repressoras/genética , Medição de Risco , Análise de Sequência de DNA , Taiwan/epidemiologia , Neoplasias do Colo do Útero/epidemiologia
2.
Cancer ; 118(1): 223-31, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21692064

RESUMO

BACKGROUND: Only a small proportion of women infected with human papillomavirus type 18 (HPV18) may progress to persistent infection and cervical neoplasia. This community-based cohort study aimed to assess associations with human leukocyte antigen (HLA) class II genotypes for natural infection of HPV18 and subsequent risk of cervical neoplasia. METHODS: Among 10,190 cytologically normal participants, 125 with HPV18 infection were identified by HPV blot kit. HPV18 viral load at study entry was examined by real-time polymerase chain reaction; persistent infection was defined as HPV18 infection at 2 consecutive examinations. RESULTS: There was a significant association between HLA-DRB1*0403 allele and high HPV18 viral load (>1000 copies in 50 ng of total DNA) at study entry (odds ratio [OR], 7.2; 95% confidence interval [CI], 2.0-25.2). After adjustment for age and viral load at study entry, haplotype HLA-DRB1*0405-DQA1*0301-DQB1*0302 was significantly associated with persistent HPV18 infection (OR, 13.3; 95% CI, 1.7-105.9). HLA-DRB1*0403 allele was also associated with a significantly increased risk of high-grade squamous intraepithelial lesion or cancer, showing a multivariate-adjusted hazard ratio (95% CI) of 18.1 (2.6-128.5). CONCLUSIONS: HLA-DRB1*0403 allele and HLA-DRB1*0405-DQA1*0301-DQB1*0302 haplotype may play important roles in determination of high viral load and persistent infection of HPV18 and subsequent cervical neoplasia risk.


Assuntos
Antígenos de Histocompatibilidade Classe II/genética , Papillomavirus Humano 18 , Infecções por Papillomavirus/genética , Displasia do Colo do Útero/genética , Estudos de Coortes , Feminino , Genótipo , Antígenos HLA/genética , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Carga Viral
3.
Int J Cancer ; 129(4): 965-73, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20949622

RESUMO

Human papillomavirus (HPV) 52 and 58 are oncogenic HPV types prevalent in Asia. Our study aims to explore intratypic variants of HPV 52 and 58 in Taiwan. A total of 11,923 women were enrolled from seven townships in 1991-1992. HPV DNA in their cervical cells was detected and typed by EasyChip® HPV blot. Among 424 participants infected with HPV 52 and/or 58, nucleotide variations were determined in cervical cell samples of 406 participants by the polymerase chain reaction sequencing of the long control region, E6 and E7 genes. Nonprototype-like variants including lineages B and C were detected in 278 (99.3%) of 280 HPV 52 samples. The prototype and prototype-like group (lineage A) of HPV58 was found in 132 (98.5%) of 134 HPV 58 samples, with sublineage A1, A2 and A3 variant in 14.2, 27.6 and 56.7%, respectively. Among women infected with single HPV 52 type, the C variant (vs. B variant) was associated with an increased prevalence of cytologically diagnosed high-grade squamous intraepithelial lesion or worse lesions showing an age-adjusted odds ratio (95% confidence interval, CI) of 5.2 (1.0-27.6) and an increased prevalence of histologically confirmed high-grade cervical intraepithelial neoplasia or more severe lesions with an age-adjusted odds ratio (95% CI) of 7.6 (1.3-43.8). It was concluded that frequency distributions of HPV 52 and 58 variants in Taiwan were different from those in European and American populations. The association between C variant of HPV 52 and prevalence of cervical neoplasia needs further validation.


Assuntos
Carcinoma de Células Escamosas/etiologia , DNA Viral/genética , Variação Genética , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Displasia do Colo do Útero/etiologia , Neoplasias do Colo do Útero/etiologia , Adulto , Idoso , Sequência de Bases , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Feminino , Seguimentos , Genótipo , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Estadiamento de Neoplasias , Papillomaviridae/classificação , Papillomaviridae/patogenicidade , Proteínas E7 de Papillomavirus/genética , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/virologia , Filogenia , Reação em Cadeia da Polimerase , Homologia de Sequência do Ácido Nucleico , Taiwan , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Esfregaço Vaginal , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
4.
Int J Cancer ; 127(3): 622-32, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19960432

RESUMO

This study aimed to evaluate whether quantitation of high-risk human papillomavirus (HR-HPV) E6 messenger RNA (mRNA) can be a potential biomarker for detecting the severity of cervical lesions. HPV genotyping was performed using a modified MY11/GP6+ PCR for HPV DNA amplification, followed by HPV genotype-specific hybridization with on a gene chip. E6 type-specific PCR was used to validate multiple infections. Quantitative real-time reverse transcriptase (QRT-PCR) and real-time PCR used to measure mRNA levels and DNA viral loads of 6 HPV oncogenic types (HPV 16, 18, 31, 33, 52 and 58) in 720 liquid-based cytology samples. The HPV DNA and RNA measurements were correlated with cervical lesions diagnosed by histopathologic examination. mRNA transcripts in the 6 types HPV DNA-positive cases was lower in normal women and

Assuntos
Alphapapillomavirus/genética , Oncogenes , RNA Mensageiro/análise , Neoplasias do Colo do Útero/virologia , Sequência de Bases , Estudos Transversais , Primers do DNA , Feminino , Humanos , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença , Neoplasias do Colo do Útero/patologia , Carga Viral
5.
Virus Res ; 161(2): 124-30, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21777630

RESUMO

A prospective, cross-sectional study was conducted to investigate the correlation between the integration of high-risk human papillomavirus and disease severity of cervical lesions. 720 liquid-based cytology specimens including 422 normal cytology, 78 low-grade squamous intraepithelial lesions, 172 high-grade squamous intraepithelial lesions, and 48 women with cervical cancers were examined using HPV blot and type-specific E6 PCR. Positive HPV DNA types 16, 18, 52 and 58 were examined for viral DNA using real-time PCR. Expression of E6 transcripts was 89.5% (pure integration), 71.7% (mixed type), and 47.1% (pure episomal) (p<0.0001). Geometric mean levels ranged from 110.6 (episomal form) to 508.4 (mixed form), and 5966.2 (integration form) by real-time PCR (p<0.0001). Geometric mean levels of E6 transcript in HPV 16, 18, 52, and 58 correlated with the severity of cervical lesions and the physical integration state of the viral genome (p<0.0001). We conclude that this is the first paper to point out that integration of high-risk HPVs not only 16 and 18 but also 52 and 58 is correlated with high levels of oncogene transcripts from normal cervix, CIN to cervical cancer.


Assuntos
Alphapapillomavirus/genética , Proteínas Oncogênicas Virais/genética , Infecções por Papillomavirus/virologia , Transcrição Gênica , Neoplasias do Colo do Útero/virologia , Integração Viral , Adulto , Alphapapillomavirus/classificação , Alphapapillomavirus/isolamento & purificação , Alphapapillomavirus/fisiologia , Colo do Útero/patologia , Colo do Útero/virologia , Estudos Transversais , Feminino , Regulação Viral da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Proteínas Oncogênicas Virais/metabolismo , Infecções por Papillomavirus/patologia , Estudos Prospectivos , Neoplasias do Colo do Útero/patologia
6.
Cornea ; 29(2): 123-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19907287

RESUMO

PURPOSE: To evaluate the prevalence and possible role of human papillomavirus (HPV) in the formation of pterygia in patients in Taiwan, a tropical country with high prevalence of pterygium. METHODS: A total of 62 patients with 65 pterygia were retrospectively examined. Ten normal conjunctiva, 8 conjunctival nevi, and 2 malignant conjunctival melanomas served as controls. HPV detection and typing were accomplished using polymerase chain reaction amplification of the viral sequences. HPV-positive specimens underwent further investigation with fluorescence in situ hybridization. Clinical histories were recorded for each patient. RESULTS: Based on polymerase chain reaction analysis, 2 of 65 pterygia harbored HPV type 18, and they were also fluorescence in situ hybridization positive. No conjunctival control had HPV. There was no statistically significant correlation between pterygium and the presence of HPV. The presence of HPV was not significantly different between primary and recurrent pterygia. CONCLUSIONS: The limited presence of HPV DNA in pterygium does not conclude that HPV is necessary or acting alone in the formation of pterygium, but HPV may still be implicated to play a role in some pterygia in Taiwan.


Assuntos
Infecções Oculares Virais/virologia , Papillomavirus Humano 18/isolamento & purificação , Infecções por Papillomavirus/virologia , Pterígio/virologia , DNA Viral/análise , Infecções Oculares Virais/diagnóstico , Infecções Oculares Virais/epidemiologia , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/epidemiologia , Reação em Cadeia da Polimerase , Prevalência , Pterígio/diagnóstico , Pterígio/epidemiologia , Recidiva , Estudos Retrospectivos , Taiwan/epidemiologia
7.
Gynecol Oncol ; 102(1): 54-60, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16386784

RESUMO

OBJECTIVE: The aim of this prospective study was to analyze whether integration or high viral loads of human papillomavirus (HPV) is essential for malignant transformation of HPV types 52 and 58 as well as types 16 and 18. METHODS: Cervical swabs from 178 consecutive patients, including 81 with invasive cervical cancers and 97 with cervical intraepithelial neoplasias (CIN) II-III, were collected and examined to determine the physical status and viral load of HPV types 16, 18, 52 and 58 DNA using genechip and real-time PCR (polymerase chain reaction) analysis. RESULTS: In cervical cancer patients, the integrated form of HPV 52 and 58 DNA was found in 25.0% and 12.5% of swabs, respectively; while HPV16 and 18 DNA was found in 82.6% and 100% of swabs, respectively (P < 0.01, for pair-wise comparison of types 16, 18 versus types 52, 58). The viral loads reflected by the amount of E6 for HPV 16, 18, or 52 were significantly increased in invasive cervical cancer compared to CINII-III (P = 0.022 for type 16, P = 0.003 for type18, and P = 0.001 for type 52, respectively). Area under the receiver operating characteristic (ROC) curve for cervical cancer versus CIN II-III was 73.8%, 92.9%, and 88.5% for HPV 16, 18, and 52, respectively, indicating that real-time PCR had good diagnostic value in differentiating cervical cancer from CIN II-III. CONCLUSIONS: Infrequent integration of HPV 52 and 58 DNA in cervical cancer suggests that it is not prerequisite for progression to cervical cancer. High viral loads (E6) of HPV 16, 18, and 52 DNA may be predictive of the transition of CIN II-III to cervical cancer. Our results indicate that both viral DNA physical status and viral loads of HPV are important factors in the carcinogenesis of different HPV types.


Assuntos
Papillomaviridae/fisiologia , Infecções por Papillomavirus/complicações , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/virologia , DNA Viral/genética , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Estadiamento de Neoplasias , Proteínas Oncogênicas Virais/genética , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Estudos Prospectivos , Proteínas Repressoras/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Carga Viral , Integração Viral , Displasia do Colo do Útero/genética , Displasia do Colo do Útero/patologia
8.
Plant Mol Biol ; 51(6): 913-24, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12777051

RESUMO

The hypersensitive response (HR) is a form of cell death associated with plant resistance to pathogen infection. Harpin(pss), an elicitor from the bacterium Pseudomonas syringae pv. syringae, induces a HR in non-host plants. Previously, we reported an amphipathic protein from sweet pepper interfering with harpin(pss)-mediated HR. In this report, we isolated and characterized a cDNA clone encoded that amphipathic protein from sweet pepper. This protein is designated as PFLP (plant ferredoxin-like protein) by virtue of its high homology with plant ferredoxin protein containing an N-terminal signal peptide responsible for chloroplast targeting and a putative 2Fe-2S domain responsible for redox activity. Recombinant PFLP obtained from Escherichia coli was able to significantly increase active oxygen species (AOS) generation when mixed with harpin(pss) in tobacco suspension cells. It also showed enhanced HR when co-infiltrated with harpin(pss) in tobacco leaves. We used a transgenic tobacco suspension cells system that constitutively expresses the Pflp gene driven by the CaMV 35S promoter to study the function of PFLP in enhancing harpin(pss)-mediated hypersensitive cell death in vivo. In response to harpin(pss), suspension cells derived from Pflp transgenic tobacco showed a significant increase both in the generation of AOS and in cell death as compared to the wild type. AOS inhibitors diphenylene iodonium chloride (DPI) and lanthanum chlorate (LaCl3) were used to study the involvement of AOS in harpin(pss)-induced cell death. Our results demonstrate enhanced generation of AOS is necessary to cause enhanced hypersensitive cell death in Pflp transgenic tobacco cells and it is plasma membrane-bound NADPH-oxidase-dependent. Sub-cellular localization studies showed that PFLP is present in the cytoplasm and chloroplast of Pflp transgenic tobacco cells, but only in the chloroplast, not in the cytoplasm, of wild-type tobacco cells. It is possible that PFLP can change the redox state of the cell upon harpin(pss) inoculation to increase AOS generation and hypersensitive cell death. Overall, this study will provide a new insight in the functional properties of ferredoxin in hypersensitive cell death.


Assuntos
Proteínas da Membrana Bacteriana Externa/farmacologia , Capsicum/genética , Ferredoxinas/genética , Ferredoxinas/fisiologia , Proteínas de Plantas/genética , Espécies Reativas de Oxigênio/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Células Cultivadas , Cloroplastos/metabolismo , Citoplasma/metabolismo , DNA Complementar/química , DNA Complementar/genética , Sinergismo Farmacológico , Ferredoxinas/farmacologia , Dados de Sequência Molecular , Folhas de Planta/citologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas , Proteínas Recombinantes/farmacologia , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Nicotiana/citologia , Nicotiana/genética
9.
Clin Endocrinol (Oxf) ; 57(5): 685-90, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12390345

RESUMO

OBJECTIVE: The significance of the association of amino terminal polymorphisms in beta2-adrenoreceptor (ADRB2) with obesity and type 2 diabetes is controversial and differs among ethnic groups. In this study, the association of ADRB2 with risk and age of onset of type 2 diabetes has been examined in a Taiwanese population. DESIGN: The study design is a case-control study to investigate the impact of the two amino acid polymorphisms in ADRB2. PATIENTS AND MEASUREMENTS: This study includes 130 patients with type 2 diabetes [female : male = 1 : 1, age: 52.4 +/- 10.0 years; body mass index (BMI): 24.2 +/- 2.9 kg/m2; mean +/- SD] and 130 controlled subjects matched for gender, age and BMI with normal glucose tolerance (female : male = 1 : 1, age: 51.7 +/- 10.6 years; BMI: 23.9 +/- 2.7 kg/m2). The Arg16Gly and Gln27Glu polymorphisms of ADRB2 were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays. The genotypic and allelic frequencies between two groups were compared and the relationship between the genotypes and clinical phenotypes was examined. RESULTS: A difference in genotypic frequency in the Arg16Gly polymorphism was noted between groups in this gender-, age- and BMI-matched case-control study (P = 0.039). Multivariate regression analysis revealed that the Arg16Gly polymorphism was the only independent factor for development of type 2 diabetes (P = 0.021). In addition, we utilized the log-rank test to compare the differences in age of onset between wild-type and nonwild-type polymorphisms. The Arg16Gly polymorphism was independently associated with age of onset in type 2 diabetes (P = 0.017). There was no difference in the Gln27Glu polymorphism between diabetic and control groups in this study. CONCLUSIONS: In a Taiwanese population, homozygosity of Arg16 in the ADRB2 gene was associated with a higher frequency (odds ratio 1.87, 95% confidence interval 1.34-2.40) for development of type 2 diabetes. Moreover, this polymorphism was also associated with an earlier onset of type 2 diabetes. However, the Glu27Gln polymorphism had no impact on either BMI or type 2 diabetes in a Taiwanese population.


Assuntos
Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/genética , Polimorfismo Genético , Receptores Adrenérgicos beta 2/genética , Adulto , Idade de Início , Estudos de Casos e Controles , Feminino , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Taiwan
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