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1.
Viruses ; 13(9)2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34578264

RESUMO

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) caused by the JC virus is the main limitation to the use of disease modifying therapies for treatment of multiple sclerosis (MS). METHODS: To assess the PML risk in course of ocrelizumab, urine and blood samples were collected from 42 MS patients at baseline (T0), at 6 (T2) and 12 months (T4) from the beginning of therapy. After JCPyV-DNA extraction, a quantitative-PCR (Q-PCR) was performed. Moreover, assessment of JCV-serostatus was obtained and arrangements' analysis of non-coding control region (NCCR) and of viral capsid protein 1 (VP1) was carried out. RESULTS: Q-PCR revealed JCPyV-DNA in urine at all selected time points, while JCPyV-DNA was detected in plasma at T4. From T0 to T4, JC viral load in urine was detected, increased in two logarithms and, significantly higher, compared to viremia. NCCR from urine was archetypal. Plasmatic NCCR displayed deletion, duplication, and point mutations. VP1 showed the S269F substitution involving the receptor-binding region. Anti-JCV index and IgM titer were found to statistically decrease during ocrelizumab treatment. CONCLUSIONS: Ocrelizumab in JCPyV-DNA positive patients is safe and did not determine PML cases. Combined monitoring of ocrelizumab's effects on JCPyV pathogenicity and on host immunity might offer a complete insight towards predicting PML risk.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Fatores Imunológicos/uso terapêutico , Vírus JC/efeitos dos fármacos , Leucoencefalopatia Multifocal Progressiva/etiologia , Esclerose Múltipla/tratamento farmacológico , Carga Viral/efeitos dos fármacos , Adulto , Proteínas do Capsídeo/genética , DNA Viral/genética , Feminino , Humanos , Vírus JC/classificação , Vírus JC/genética , Vírus JC/patogenicidade , Leucoencefalopatia Multifocal Progressiva/sangue , Leucoencefalopatia Multifocal Progressiva/urina , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Esclerose Múltipla/complicações , Esclerose Múltipla/urina , Filogenia , Medição de Risco , Viremia/tratamento farmacológico
2.
J BUON ; 20(3): 762-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26214628

RESUMO

PURPOSE: Several reports have indicated the presence of JC polyomavirus (JCV) in many human tumors, including colorectal cancers (CRCs). The presence of JCV infection in CRC patients has not been investigated in African countries. METHODS: We examined the prevalence and the biological significance of JCV in Tunisian CRC patients. The presence of JCV was assessed by polymerase chain reaction (PCR) in a series of 105 CRCs and 89 paired non-tumor colonic mucosa samples from Tunisian patients. Results were correlated with the clinicopathological features and immunohistochemical expression of ß-catenin, p53, and the proliferation marker Ki-67. RESULTS: JCV DNA was detected in 58.1% (61/105) of CRC and in only 14.6% (13/89) of paired non tumor colonic mucosa samples (p=0.03). The presence of JCV was significantly correlated with tumor differentiation (p=0.03). Moreover, JCV presence was significantly correlated with nuclear accumulation of ß-catenin (p=0.008) and p53 accumulation (p=0.0001). Multivariate logistic regression analysis showed that tumor differentiation, ß-catenin and p53 accumulation were independent parameters significantly associated with the presence of JCV in CRC (p=0.04; p=0.05; p=0.001, respectively). CONCLUSION: We support a role of JCV in colorectal carcinogenesis in Tunisian patients, especially of well differentiated morphology.


Assuntos
Adenocarcinoma Mucinoso/virologia , Adenocarcinoma/virologia , Neoplasias Colorretais/virologia , Vírus JC/isolamento & purificação , Infecções por Polyomavirus/virologia , Infecções Tumorais por Vírus/virologia , Adenocarcinoma/química , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Adenocarcinoma Mucinoso/química , Adenocarcinoma Mucinoso/epidemiologia , Adenocarcinoma Mucinoso/patologia , Biomarcadores Tumorais/análise , Estudos de Casos e Controles , Diferenciação Celular , Neoplasias Colorretais/química , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/patologia , DNA Viral/isolamento & purificação , Feminino , Humanos , Imuno-Histoquímica , Vírus JC/genética , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Reação em Cadeia da Polimerase , Infecções por Polyomavirus/epidemiologia , Infecções por Polyomavirus/metabolismo , Infecções por Polyomavirus/patologia , Prevalência , Proteína Supressora de Tumor p53/análise , Infecções Tumorais por Vírus/epidemiologia , Infecções Tumorais por Vírus/metabolismo , Infecções Tumorais por Vírus/patologia , Tunísia/epidemiologia , beta Catenina/análise
3.
J Neurovirol ; 18(1): 55-61, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22281875

RESUMO

Polyomavirus JC (JCV) reactivation causing progressive multifocal leukoencephalopathy is a main concern during biological therapies. Here, JCV reactivation in patients suffering from immune-mediated diseases after a long-term treatment with anti-tumor necrosis factor alpha (TNF-α) inhibitor infliximab was investigated. Peripheral mononuclear blood cells (PBMC), plasma and urine samples were obtained from 61 immune-mediated diseases patients treated or not with infliximab in combination with steroid and other immunomodulators and from 20 healthy donors. JCV DNA was transiently detected in 12 PBMC of 40 patients at different doses of infliximab with a higher prevalence than that of the 21 patients untreated. Conversely, a stable JCV positivity in urine of treated and untreated patients was detected. Sequencing the noncoding control region (NCCR), all samples exhibited the archetype structure with few mutations in transcriptional factor binding regions. The consequence of anti-TNF-α treatment on viral persistence was examined monitoring Torquetenovirus viremia and investigating the TNF-α-induced microRNA regulators of transcriptional factors, with a binding site on NCCR. Although infliximab treatment in this study did not affect directly JCV reactivation, further investigation on host factor(s) regulated by it will be of warranty in the understanding the mechanism(s) that may affect viral persistence.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Vírus JC/genética , Leucócitos Mononucleares/virologia , Leucoencefalopatia Multifocal Progressiva/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/uso terapêutico , Estudos de Casos e Controles , Feminino , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/uso terapêutico , Infliximab , Vírus JC/patogenicidade , Leucócitos Mononucleares/imunologia , Leucoencefalopatia Multifocal Progressiva/sangue , Leucoencefalopatia Multifocal Progressiva/imunologia , Leucoencefalopatia Multifocal Progressiva/urina , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/imunologia , Ativação Viral/efeitos dos fármacos , Ativação Viral/imunologia
4.
Arch Virol ; 157(2): 315-21, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22134526

RESUMO

We investigated the frequency of BKV, JCV and SV40 reactivation in three groups of Cuban patients by multiplex nested PCR assay of 40 paraffin-embedded colorectal neoplasm tissues, 113 urine samples, and 125 plasma samples from 27 transplant recipients, and cerebrospinal fluid (CSF) from 67 HIV-1-infected individuals with central nervous system (CNS) disorders. None of these polyomaviruses were detected in colorectal neoplasms. JCV DNA was detected in 2 of 67 patients (2.9%) with CNS disorders, but neither BKV nor SV40 was identified. BKV was found in urine from 38.5% and 28.6% of adult and pediatric transplant recipients, respectively. In adult renal transplant recipients, excretion of BKV in urine was significantly associated with episodes of acute rejection (p=0.012) and with excretion of HCMV in urine (p= 0.008). In Cuba, the polyomaviruses studied here could not be related to colorectal neoplasms, and JCV was rarely detected in CSFs of HIV-1-infected individuals, whilst BKV reactivation was found to occur frequently in organ transplant recipients.


Assuntos
Vírus BK/isolamento & purificação , Vírus JC/isolamento & purificação , Infecções por Polyomavirus/virologia , Vírus 40 dos Símios/isolamento & purificação , Infecções Tumorais por Vírus/virologia , Adulto , Vírus BK/genética , Vírus BK/fisiologia , Cuba , Feminino , Humanos , Vírus JC/genética , Vírus JC/fisiologia , Masculino , Pessoa de Meia-Idade , Vírus 40 dos Símios/genética , Vírus 40 dos Símios/fisiologia , Adulto Jovem
6.
J Clin Virol ; 48(1): 6-10, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20335066

RESUMO

BACKGROUND: JC virus (JCV), the causative agent of progressive multifocal leukoencephalopathy (PML), is classified in 8 different genotypes. Previous reports have suggested a positive association between specific genotypes and PML. OBJECTIVE: To compare genotypes and adaptive mutations of JCV strains from Brazilian AIDS patients with and without PML. STUDY DESIGN: The VP1 region of JCV was amplified by polymerase chain reaction from cerebrospinal fluid samples from 51 patients with PML and from urine samples of 47 patients with AIDS without central nervous system disease. Genotyping was done by phylogenetic analysis. Amino acid replacement and selection pressures were also investigated. RESULTS: JCV genotype frequency distributions showed that genotypes 2 (32.7%), 1 (26.5%) and 3 (23.5%) were the most prevalent. Genotype 1 had a positive association (p<0.0001) and genotype 3 showed an inverse association (p<0.001) with PML. A previously undescribed point mutation at residue 91 (L/I or L/V) and (L/P), non-genotype-associated, was found in 5/49 (10.2%) and 2/47 (4.3%) JCV sequences from PML and non-PML patients, respectively. This mutation was under positive selection only in PML patients. A previously described substitution of T-A in position 128 showed a significant difference between PML and non-PML cases (70% versus 16%, respectively, p<0.0005). CONCLUSION: In Brazilian patients with AIDS, JCV genotype 1 showed a strong association with PML (p<0.0001) and JCV genotype 3 showed an inverse association with PML. The possible association of aminoacids substitution in residues 91 and 128 with PML in patients with AIDS must be further investigated.


Assuntos
Infecções por HIV/virologia , Vírus JC/genética , Leucoencefalopatia Multifocal Progressiva/virologia , Substituição de Aminoácidos , Teorema de Bayes , Brasil , Proteínas do Capsídeo/genética , Distribuição de Qui-Quadrado , DNA Viral/análise , Genótipo , Infecções por HIV/complicações , Humanos , Leucoencefalopatia Multifocal Progressiva/líquido cefalorraquidiano , Leucoencefalopatia Multifocal Progressiva/complicações , Leucoencefalopatia Multifocal Progressiva/urina , Método de Monte Carlo , Filogenia , Análise de Sequência de DNA
7.
Dis Colon Rectum ; 48(1): 86-91, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15690663

RESUMO

PURPOSE: Research data have recently emphasized an intriguing association of JC polyoma virus with colon carcinogenesis. Tumorigenicity of JC virus is attributed to the T-antigen of its Mad-1 variant. Controversy arose when another research group did not confirm this association. The purpose of this study was to detect JC virus in a series of colon neoplasms from Greek patients. METHODS: A nested polymerase chain reaction assay was used to detect JC virus in 80 cancerous, 25 adenomatous specimens of large bowel, and 20 colonoscopic biopsy samples from normal patients without colorectal neoplasia. Quantitation of JC virus DNA was performed by real-time polymerase chain reaction. RESULTS: JC polyoma virus nucleotide sequence was detected in 61 percent of colon adenocarcinomas and in 60 percent of adenomas, at a viral load of 9 x 10(3) to 20 x 10(3) copies/microg DNA. Adjacent normal mucosa in 35 positive colon adenocarcinoma specimens, and normal mucosa from six patients of the control group, had low viral loads (50-450 copies/microg DNA). CONCLUSIONS: JC polyoma virus genome is present in colon neoplasms. JC virus detection in adenomas at comparable viral loads to malignant tumors suggests its implication at early steps of colonic carcinogenesis. Taking into consideration other published data, infection of colonic epithelium with JC virus might be a prime candidate for a role in chromosomal and genomic instability.


Assuntos
Adenocarcinoma/virologia , Adenoma/virologia , Neoplasias do Colo/virologia , Vírus JC/patogenicidade , Infecções Tumorais por Vírus/complicações , Adenocarcinoma/etiologia , Adenoma/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Neoplasias do Colo/etiologia , Colonoscopia , DNA Viral/análise , Feminino , Humanos , Vírus JC/genética , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Fatores de Risco
8.
Notes Undergr ; (no 29): 4-6, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-11362283

RESUMO

AIDS: PML is a rare disease that destroys myelin tissue in the central nervous system and causes lesions in the brain. Probably caused by the JC virus, the disorder can proceed rapidly. Currently there is no treatment for PML. However, Dr. Khalili at Thomas Jefferson University published research showing that topotecan, an analogue of campthotecin (derived from the bark of a chinese tree), suppresses the JC virus in the test tube at low doses. Although this is promising, it is unclear how well the drug crosses the blood-brain barrier or even if targeting the JC virus is the best way to stop PML. The drug is in phase II/III cancer trials. Although toxic, topotecan appears to inhibit the JC virus at lower doses than for cancer. SmithKline Beecham (SKB) owns the license to develop topotecan. SKB has had little interest in AIDS research since their protease inhibitor did not pan out. Responding to activists, SKB announced that they are pursuing topotecan as an anti-HIV drug, with studies opening this spring. There are other derivatives of campthotecin, 9-A-C and CPT-11 or irinotecan. 9-A-C does not work in the test tube; however, CPT-11, a cancer drug from Japan, is being studied by Upjohn. Upjohn supplied Dr. Khalili with CPT-11 and SN-38. Dr. Khalili found that both inhibited the JC virus in the test tube, and that SN-38 was a better JCV inhibitor than topotecan. Dr. Sidney Huff, Georgetown, has requested and received compassionate use for two PML patients.^ieng


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Albendazol/uso terapêutico , Camptotecina/uso terapêutico , Leucoencefalopatia Multifocal Progressiva/tratamento farmacológico , Microsporidiose/tratamento farmacológico , Barreira Hematoencefálica , Camptotecina/análogos & derivados , Camptotecina/farmacocinética , Camptotecina/farmacologia , Indústria Farmacêutica , Humanos , Irinotecano , Vírus JC/efeitos dos fármacos , Vírus JC/genética , Vírus JC/isolamento & purificação , Leucoencefalopatia Multifocal Progressiva/complicações , Reação em Cadeia da Polimerase , Topotecan
9.
J Biol Chem ; 269(2): 1046-50, 1994 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-8288559

RESUMO

The regulation of glial-specific JC virus early gene expression was addressed by functional dissection of a previously uncharacterized form of the JC virus promoter (MH-1). The MH-1 promoter directed 31-fold higher reporter gene expression in U87MG glioma cells than in HeLa cells in a transient transfection assay. Transfection of promoter constructs containing proximal or proximal plus upstream regions revealed that reporter gene expression was activated by both proximal and tandem repeat regions in glioma cells. The proximal region contains a guanine-rich sequence, the GA box, which was found to regulate the promoter, and was recognized specifically by the transcription factor Sp1. The GA box is also present in the promoters of three glial-specific cellular genes. Together with paired AP-1 and NF-1 sites in the tandem repeats, the GA box is part of a motif that is conserved between several glial-specific promoters, and is thus a potential determinant of glial-specific gene expression. These results delineate the promoter regions required for activation of the MH-1 JC virus promoter, suggest a new determinant of glial specificity, and establish a model for the investigation of combinatorial activation of a glial-specific viral promoter.


Assuntos
Regulação Viral da Expressão Gênica , Vírus JC/genética , Neuroglia/fisiologia , Regiões Promotoras Genéticas , Fator de Transcrição Sp1/fisiologia , Sequência de Bases , Análise Mutacional de DNA , Primers do DNA/química , Células HeLa , Humanos , Dados de Sequência Molecular , Neuroglia/microbiologia , RNA Mensageiro/genética , Deleção de Sequência , Transcrição Gênica
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