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1.
Int J Cancer ; 153(5): 1043-1050, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37318089

RESUMO

In 2017, the World Health Organization (WHO) confirmed a new entity, Epstein Barr virus (EBV) + Diffuse large B cell lymphoma (DLBCL), not otherwise specified (NOS). Traces of EBV transcripts were described in lymphomas, including DLBCL, that were diagnosed as EBV negative by conventional methods. The aim of this study was to detect viral genome by qPCR, as well as LMP1 and EBNA2 transcripts, with a more sensitive method in DLBCL cases from Argentina. Fourteen cases originally considered as EBV negative expressed LMP1 and/or EBNA2 transcripts. In addition, LMP1 and/or EBNA2 transcripts were also observed in bystander cells. However, EBERs+ cells cases by conventional ISH showed higher numbers of cells with LMP1 transcripts and LMP1 protein. In the cases that were EBERS- in tumor cells but with expression of LMP1 and/or EBNA2 transcripts, the viral load was below the limit of detection. This study provides further evidence that EBV could be detected in tumor cells by more sensitive methods. However, higher expression of the most important oncogenic protein, LMP1, as well as increased viral load, are only observed in cases with EBERs+ cells by conventional ISH, suggesting that traces of EBV might not display a key role in DLBCL pathogenesis.


Assuntos
Infecções por Vírus Epstein-Barr , Linfoma Difuso de Grandes Células B , Humanos , Adulto , Criança , Herpesvirus Humano 4/genética , Linfoma Difuso de Grandes Células B/patologia , Argentina , Antígenos Nucleares do Vírus Epstein-Barr/genética , Proteínas da Matriz Viral/genética
2.
Blood ; 141(19): 2290-2291, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37166929
3.
Hematol Oncol ; 36(1): 98-103, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28707331

RESUMO

Epstein-Barr virus (EBV)-mediated B cell transformation is achieved predominantly through the action of latent proteins, but recent evidence suggests that lytic EBV replication has also a certain pathogenic role in lymphomagenesis, at least in the early phases of cell transformation. Particularly, in diffuse large B cell lymphoma (DLBCL), the EBV lytic cycle is by and large unexplored, so to disclose lytic cell contribution to lymphomagenesis, our aim was to evaluate viral early and late lytic gene expression in relation to several immune response markers in a series of EBV+ DLBCL from Argentina. An unexpected number of cells expressed lytic transcripts, being transcribed at the BZLF1, BHRF1, and BLLF1 locus, by real-time quantitative polymerase chain reaction. This lytic antigen expression was confirmed by immunohistochemical staining for BMRF1 early lytic protein, and a positive correlation between lytic and latent genes was confirmed, revealing a close link between their expressions in EBV+ DLBCL pathogenesis. Remarkably, BZLF1 displayed a negative correlation with CD4 cell counts, and this could be in part justified by the restriction of antigen presentation previously reported. The direct correlation for the late lytic gene BLLF1 and IFNγ in this series could represent a specific response directed towards this antigen. Interleukin 10 transcripts also displayed a positive correlation with lytic expression, indicating that regulatory mechanisms could be also involved on EBV-associated DLBCL pathogenesis in our series. Complete lytic reactivation in EBV-positive tumours could potentially kill EBV-positive malignant cells, providing a tool to promote tumour cell killing mediated by EBV as a complementary treatment strategy.


Assuntos
Imuno-Histoquímica/métodos , Linfoma Difuso de Grandes Células B/virologia , Humanos , Linfoma Difuso de Grandes Células B/patologia
4.
Med Microbiol Immunol ; 207(5-6): 319-327, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30046954

RESUMO

Epstein Barr virus (EBV) gains access to the host through tonsillar crypts. Our aim was to characterize microenvironment composition around EBV+ cells in tonsils from pediatric carriers, to disclose its role on viral pathogenesis. LMP1 expression, assessed by immunohistochemistry (IHC), was used to discriminate EBV + and - zones in 41 tonsil biopsies. Three regions were defined: Subepithelial (SE), interfollicular (IF) and germinal center (GC). CD8, GrB, CD68, IL10, Foxp3, PD1, CD56 and CD4 markers were evaluated by IHC; positive cells/100 total cells were counted. CD8+, GrB+, CD68+ and IL10+ cells were prevalent in EBV+ zones at the SE region (p < 0.0001, p = 0.03, p = 0.002 and p = 0.002 respectively, Wilcoxon test). CD4+ and CD68+ cell count were higher in EBV + GC (p = 0.01 and p = 0.0002 respectively, Wilcoxon test). Increment of CD8, GrB and CD68 at the SE region could indicate a specific response that may be due to local homing at viral entry, which could be counterbalanced by IL10, an immunosuppressive cytokine. Additionally, it could be hypothesized that CD4 augment at the GC may be involved in the EBV-induced B-cell growth control at this region, in which macrophages could also participate.


Assuntos
Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4/imunologia , Imunidade Celular , Tonsila Palatina/patologia , Tonsila Palatina/virologia , Adolescente , Biomarcadores/análise , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Masculino , Proteínas da Matriz Viral/análise
5.
J Med Virol ; 86(5): 845-50, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24027016

RESUMO

The aim of this study is to characterize EBV expression and latency pattern in pediatric Burkitt's lymphoma in a single institution in Argentina. EBV-encoded RNA or protein was analyzed in 27 patients. EBERs was expressed in 37% of patients (29% of immunocompetent and 100% of immunosuppressed patients). EBV-positive cases were observed exclusively in patients younger than 5 years old. EBV association with immunocompetent patients exhibits the sporadic pattern in region under study, while its presence in patients infected with HIV was higher than described previously. EBV latency I profile was present in most of the patients, except for two immunosuppressed patients who displayed LMP1 expression.


Assuntos
Linfoma de Burkitt/virologia , Infecções por Vírus Epstein-Barr/epidemiologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/fisiologia , Ativação Viral , Latência Viral , Adolescente , Argentina/epidemiologia , Criança , Pré-Escolar , Feminino , Perfilação da Expressão Gênica , Herpesvirus Humano 4/isolamento & purificação , Humanos , Lactente , Masculino , RNA Viral/biossíntese , Estudos Retrospectivos , Proteínas Virais/biossíntese
6.
Sci Rep ; 14(1): 2135, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273012

RESUMO

CD4 T cells play a key role in Epstein Barr virus (EBV) infection, by modulating latent antigen expression, and exhibiting cytotoxic and regulatory properties. Our aim was to evaluate the presence of Granzyme B (GZMB) and Foxp3 CD4 T cells at different EBV infection status and latency profiles. We examined CD4, GZMB, Foxp3, IL10, TGF-ß, CD4-GZMB and CD4-Foxp3 expression at the tonsils of pediatric patients with different infective status and EBV latency profiles. CD4+, GZMB+, Foxp3+, CD4-GZMB+ and CD4-Foxp3+ cell counts were higher at the interfollicular region. Higher expression of CD4-GZMB was found in primary infected patients compared to healthy carriers. In patients that expressed latency III antigens, we demonstrated lower CD4+, CD4-GZMB+, CD4-Foxp3+ expression; a negative correlation between the immunoregulatory cytokine IL-10+ and GZMB+ as well as a positive correlation of IL-10+ and CD4+. In patients expressing the lytic protein BMRF1, a positive correlation of TGF-ß+ with CD4-GZMB+ and CD4-Foxp3+ was observed. Our findings indicate that CD4-GZMB+ cells are involved in the restriction of primary EBV infection in pediatric patients, which could partially explain the lack of symptoms, whereas both CD4-GZMB+ and CD4-Foxp3+ cells could be involved in the modulation of latency.


Assuntos
Infecções por Vírus Epstein-Barr , Humanos , Criança , Herpesvirus Humano 4 , Linfócitos T CD4-Positivos , Interleucina-10 , Tonsila Palatina , Fator de Crescimento Transformador beta , Fatores de Transcrição Forkhead
7.
Int J Cancer ; 133(6): 1286-92, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23001576

RESUMO

In most underdeveloped countries, the initial contact with Epstein Barr virus (EBV) usually happens in the first decade of life and results in an asymptomatic infection, whereas in developed areas, primary infection in adolescence or adulthood is accompanied by infectious mononucleosis in 50% cases. Although it is generally a harmless passenger, in some individuals, it is associated with B-cell lymphoma. In Argentina, EBV primary infection shows the classical pattern observed in developing populations, given that nearly 70% of patients are seropositive by the age of 2 years. However, EBV association with pediatric Hodgkin and Burkitt lymphoma resembles that observed in developed regions. Concerning diffuse large B-cell lymphoma, our series demonstrated higher EBV association than other adult ones from either developed or underdeveloped countries. Interestingly, the early EBV primary infection observed, characteristic of an underdeveloped population, together with the statistically significant EBV association with patients ≤ 10 years old demonstrated in all types of lymphoma studied, suggest a relationship between low age of EBV seroconversion and B-cell lymphoma development risk.


Assuntos
Infecções por Vírus Epstein-Barr/complicações , Linfoma de Células B/etiologia , Adolescente , Argentina/epidemiologia , Criança , Pré-Escolar , Infecções por Vírus Epstein-Barr/epidemiologia , Humanos , Lactente , Linfoma de Células B/virologia , Linfoma não Hodgkin/etiologia
8.
Int J Cancer ; 132(7): 1572-80, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22987474

RESUMO

Non-Hodgkin's lymphoma represents 6-10% of pediatric malignancies, and diffuse large B-cell lymphoma (DLBCL) is one of the three major subtypes. The 2008 WHO classification included a new entity, Epstein-Barr virus (EBV)-positive DLBCL of the elderly, affecting patients >50 years. It has been demonstrated that EBV may play a role in tumor microenvironment composition, disturbing antitumor immune response and disease progression. As most studies were performed in adults, our aim was to assess EBV presence and latency pattern, as well as T-cell microenvironment in a pediatric DLBCL series of Argentina. The study was conducted on formalin-fixed paraffin-embedded biopsies from 25 DLBCL patients. EBV-encoded small nuclear early regions (EBERs) expression was performed by in situ hybridization, whereas EBV gene expression was analyzed using real-time PCR. Epstein-Barr virus latent membrane proteins (LMP)1, LMP2A, CD3, CD4, CD8 and Foxp3 expression were assessed by immunohistochemistry (IHC). Forty percent of cases showed EBV expression, with a significantly higher incidence among patients <10 years (p = 0.018), and with immunosuppressed (p = 0.023). T-cell subsets were not altered by EBV presence. Full EBV latency antigen expression (latency type III) was the most frequently pattern observed, together with BZLF1 lytic gene expression. One patient showed II-like pattern (LMP1 without LMP2A expression). Based exclusively on IHC, some patients showed latency II/III (EBERs and LMP1 expression) or I (EBERs only). These findings suggest that EBV association in our series was higher than the previously demonstrated for elderly DLBCL and that EBV latency pattern could be more complex from those previously observed. Therefore, EBV could be an important cofactor in pediatric DLBCL lymphomagenesis.


Assuntos
Infecções por Vírus Epstein-Barr/epidemiologia , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Herpesvirus Humano 4/fisiologia , Linfoma Difuso de Grandes Células B/virologia , Microambiente Tumoral , Proteínas da Matriz Viral/metabolismo , Latência Viral , Adolescente , Argentina/epidemiologia , Criança , Pré-Escolar , Infecções por Vírus Epstein-Barr/diagnóstico , Infecções por Vírus Epstein-Barr/etiologia , Antígenos Nucleares do Vírus Epstein-Barr/genética , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Hibridização In Situ , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/patologia , Masculino , Prevalência , Prognóstico , RNA Mensageiro/genética , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/virologia , Carga Viral , Proteínas da Matriz Viral/genética
9.
Viruses ; 15(10)2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37896882

RESUMO

Macrophages are exceptionally flexible cells. The presence of inflammatory cytokines such as IFN-γ and TNF-α results in an M1 (CD68) activation, while cytokines such as IL-10 or TGF-ß induce the M2 (CD163) activation. Our aim was to study the behavior of peripheral cytokines involved in macrophage polarization and relate them with tissue findings to further comprehend the role of macrophages in EBV pediatric infection. We studied cytokine expression in tonsils and peripheral blood samples of children in different stages of infection. Peripheral cytokines were compared with macrophage polarization markers and viral protein expression in tonsils. Only IL-10 showed a negative correlation between compartments, exclusively in patients undergoing viral reactivation (R). Higher expressions of peripheral IL-1ß, IL-23, and IL-12p40 in R children were observed. Lower expressions of local and peripheral TNF-α in patients with broader expressions of latent and lytic viral proteins were demonstrated. In healthy carrier (HC) patients, IL-23 positively correlated with CD163, and IP-10 positively correlated with CD68. Our results indicated that EBV might modulate antigen expression in the presence of TNF-α and influence peripheral cytokine expression differently in each stage of infection. Moreover, peripheral cytokines might have a particular role in macrophage polarization in HC.


Assuntos
Citocinas , Infecções por Vírus Epstein-Barr , Humanos , Criança , Citocinas/metabolismo , Interleucina-10/metabolismo , Herpesvirus Humano 4/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Macrófagos , Infecções por Vírus Epstein-Barr/metabolismo , Interleucina-23
10.
J Clin Microbiol ; 50(3): 609-18, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22205789

RESUMO

The ubiquitous Epstein-Barr virus (EBV) is related to the development of lymphoma and is also the etiological agent for infectious mononucleosis (IM). Sequence variations in the gene encoding LMP1 have been deeply studied in different pathologies and geographic regions. Controversial results propose the existence of tumor-related variants, while others argued in favor of a geographical distribution of these variants. Reports assessing EBV variants in IM were performed in adult patients who displayed multiple variant infections. In the present study, LMP1 variants in 15 pediatric patients with IM and 20 pediatric patients with EBV-associated lymphomas from Argentina were analyzed as representatives of benign and malignant infections in children, respectively. A 3-month follow-up study of LMP1 variants in peripheral blood cells and in oral secretions of patients with IM was performed. Moreover, an integrated linkage analysis was performed with variants of EBNA1 and the promoter region of BZLF1. Similar sequence polymorphisms were detected in both pathological conditions, IM and lymphoma, but these differ from those previously described in healthy donors from Argentina and Brazil. The results suggest that certain LMP1 polymorphisms, namely, the 30-bp deletion and high copy number of the 33-bp repeats, are associated with EBV-related pathologies, either benign or malignant, instead of just being tumor related. Additionally, this is the first study to describe the Alaskan variant in EBV-related lymphomas that previously was restricted to nasopharyngeal carcinomas from North America.


Assuntos
Linfoma de Burkitt/virologia , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/patogenicidade , Mononucleose Infecciosa/virologia , Polimorfismo Genético , Proteínas da Matriz Viral/genética , Adolescente , Argentina , Linfoma de Burkitt/patologia , Criança , Pré-Escolar , DNA Viral/química , DNA Viral/genética , Antígenos Nucleares do Vírus Epstein-Barr/genética , Feminino , Herpesvirus Humano 4/isolamento & purificação , Humanos , Lactente , Mononucleose Infecciosa/patologia , Linfoma/patologia , Linfoma/virologia , Masculino , Dados de Sequência Molecular , Análise de Sequência de DNA , Transativadores/genética
11.
Front Immunol ; 13: 940910, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36451810

RESUMO

Epstein-Barr Virus (EBV) is a tumor associated virus that modulates not only the infected cells but also innate and adaptive immunity. Macrophages play a key role in tumor development and progression. Particularly, the M2 phenotype (CD163) with anti-inflammatory activity contributes to a favorable microenvironment for tumor development while the M1 (CD68) proinflammatory phenotype contributes to a restrictive one. In the context of pediatric EBV infection, little is known about macrophage contribution to PD-L1 expression, a molecule involved in immune exhaustion. We studied tonsils of primary infected (PI), healthy carriers (HC), reactivated (R), and not infected (NI) pediatric patients. Positive correlations were demonstrated for CD68+PD-L1+ in R and for CD163+PD-L1+ only in PI. Furthermore, CD163+PD-L1+ cell numbers were higher than PD-L1+CD68+ in PI patients. In addition, a positive correlation between PD-L1+CD163+ cells and LMP1 viral latent protein was observed in PI patients, and a positive correlation between PD-L1+CD68+ cells and BMRF1 lytic antigen was demonstrated. A positive correlation between TGF-ß and PD-L1 expression was demonstrated in HC patients. Our findings indicate that EBV's lytic and latent antigens might be regulating macrophages' PD-L1 expression, particularly in PI patients, whereas, surprisingly, only TGF-ß could be related to total PD-L1 upregulation. Given the relevance of macrophages and the PD-1/PD-L1 pathway in tumor progression and survival, more studies in early EBV infection could help to develop EBV-associated tumor therapies.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Humanos , Antígeno B7-H1 , Contagem de Leucócitos , Macrófagos , Vírus Oncogênicos , Tonsila Palatina , Fator de Crescimento Transformador beta
12.
Front Oncol ; 12: 957208, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992809

RESUMO

In pediatric Hodgkin lymphoma (HL), the inability of the cytotoxic microenvironment induced by EBV presence to eliminate tumor cells could reflect the fact that the virus might be able to induce the expression of exhaustion markers to evade an immune response. Therefore, the expression of exhaustion markers in pediatric EBV-associated HL was evaluated. A balance between cytotoxic GrB and Th1 Tbet markers with regulatory Foxp3 was proved in EBV+ cases. In addition, exclusively in EBV-associated cHL, a correlation between PD-1 and LAG-3 expression was observed. Furthermore, those cases also displayed a trend to worse survival when they expressed LAG-3 and inferior event-free survival when both PD-1 and LAG-3 molecules were present. Therefore, even though a cytotoxic and inflammatory environment was supposed to be triggered by EBV presence in pediatric cHL, it seems that the virus may also induce the synergic effect of inhibitory molecules LAG-3 and PD-1 in this series. These observations may reflect the fact that the permissive and exhausted immune microenvironment succeeds to induce lymphomagenesis.

13.
Microorganisms ; 10(5)2022 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-35630333

RESUMO

High-risk human papillomaviruses (HR-HPVs) are the etiological agents of cervical cancer. However, a low proportion of HR-HPV-infected women finally develop this cancer, which suggests the involvement of additional cofactors. Epstein−Barr virus (EBV) has been detected in cervical squamous cell carcinomas (SCCs) as well as in low- (LSIL) and high-grade (HSIL) squamous intraepithelial lesions, although its role is unknown. In this study, we characterized HR-HPV/EBV co-presence and viral gene expression in LSIL (n = 22), HSIL (n = 52), and SCC (n = 19) from Chilean women. Additionally, phenotypic changes were evaluated in cervical cancer cells ectopically expressing BamHI-A Rightward Frame 1 (BARF1). BARF1 is a lytic gene also expressed in EBV-positive epithelial tumors during the EBV latency program. HPV was detected in 6/22 (27.3%) LSIL, 38/52 (73.1%) HSIL, and 15/19 (78.9%) SCC cases (p < 0.001). On the other hand, EBV was detected in 16/22 (72.7%) LSIL, 27/52 (51.9%) HSIL, and 13/19 (68.4%) SCC cases (p = 0.177). HR-HPV/EBV co-presence was detected in 3/22 (13.6%) LSIL, 17/52 (32.7%) HSIL, and 11/19 (57.9%) SCC cases (p = 0.020). Additionally, BARF1 transcripts were detected in 37/55 (67.3%) of EBV positive cases and in 19/30 (63.3%) of HR-HPV/EBV positive cases. Increased proliferation, migration, and epithelial-mesenchymal transition (EMT) was observed in cervical cancer cells expressing BARF1. Thus, both EBV and BARF1 transcripts are detected in low- and high-grade cervical lesions as well as in cervical carcinomas. In addition, BARF1 can modulate the tumor behavior in cervical cancer cells, suggesting a role in increasing tumor aggressiveness.

14.
Cancers (Basel) ; 13(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072731

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin's lymphoma (NHL) in adults. Epstein-Barr virus (EBV) positive DLBCL of the elderly was defined by the World Health Organization (WHO) in 2008, it was restricted only to patients older than 50 years old, and it was attributed to immunesenescence associated with physiological aging. After the description of EBV-associated DLBCL in children and young adults, the WHO redefined the definition, leading to the substitution of the modifier "elderly" with "not otherwise specified" (EBV + DLBCL, NOS) in the updated classification, and it is no more considered provisional. The incidence of EBV + DLBCL, NOS varies around the world, in particular influenced by the percentage of EBV+ cells used as cut-off to define a case as EBV-associated. EBV has effect on the genetic composition of tumor cells, on survival, and at the recruitment of immune cells at the microenvironment. In this review, the role of EBV in the pathogenesis of DLBCL is discussed.

15.
J Med Virol ; 82(10): 1730-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20827771

RESUMO

Epstein-Barr virus (EBV) is related to the development of lymphomas and is also the etiological agent for infectious mononucleosis (IM). Sequence variation of the EBNA1 gene, consistently expressed in all EBV-positive cells, has been widely studied. Based on the amino acid at codon 487 five major EBNA1 variants have been described, two closely related prototypic variants (P-ala and P-thr) and three variant sequences (V-leu, V-val, and V-pro). Sub-variants were then further classified based on mutations other than the originally described. While several studies proposed associations with tumors and/or anatomical compartments, others argued in favor of a geographical distribution of these variants. In the present study, EBNA1 variants in 11 pediatric patients with IM and 19 pediatric EBV lymphomas from Argentina were compared as representatives of benign and malignant infection in children, respectively. A 3-month follow-up study of EBNA1 variants in peripheral blood cells and in oral secretions of patients with IM was performed. A new V-ala variant which includes five V-ala sub-variants and three new V-leu sub-variants was described. These data favor the geographical association hypothesis since no evidence for a preferential compartment distribution of EBNA1 variants and sub-variants was found. This is the first study to characterize EBNA1 variants in pediatric patients with infection mononucleosis worldwide.


Assuntos
Infecções por Vírus Epstein-Barr/epidemiologia , Infecções por Vírus Epstein-Barr/virologia , Antígenos Nucleares do Vírus Epstein-Barr/genética , Herpesvirus Humano 4/classificação , Herpesvirus Humano 4/genética , Polimorfismo Genético , Adolescente , Argentina/epidemiologia , Sangue/virologia , Secreções Corporais/virologia , Pré-Escolar , Análise por Conglomerados , DNA Viral/química , DNA Viral/genética , Feminino , Genótipo , Herpesvirus Humano 4/isolamento & purificação , Humanos , Linfócitos/virologia , Masculino , Epidemiologia Molecular , Dados de Sequência Molecular , Nariz/virologia , Filogenia , Análise de Sequência de DNA
16.
Pathogens ; 9(1)2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31963774

RESUMO

In Argentina, Epstein-Barr virus (EBV) presence is associated with Hodgkin lymphoma (HL) in patients younger than 10 years, suggesting a relationship between low age of EBV infection and HL. Given that HL is derived from germinal centers (GC), our aim was to compare EBV protein expression and microenvironment markers between pediatric HL patients and EBV+GC in children. METHODS: EBV presence and immune cell markers were assessed by in situ hybridization and immunohistochemistry (IHC). RESULTS: Viral latency II pattern was proved in all HL patients and in 81.8% of EBV+ tonsillar GCs. LMP1 and LMP2 co-expression were proved in 45.7% HL cases, but only in 7.7% EBV+ GC in pediatric tonsils. An increase in CD4+, IL10, and CD68+ cells was observed in EBV+ GC. In pediatric HL patients, only the mean of IL10+ cells was statistically higher in EBV+ HL. CONCLUSIONS: Our findings point us out to suggest that LMP1 expression may be sufficient to drive neoplastic transformation, that an immune regulatory milieu counteracts cytotoxic environment in EBV-associated Hodgkin lymphoma, and that CD4+ and CD68+ cells may be recruited to act in a local collaborative way to restrict, at least in part, viral-mediated lymphomagenesis in tonsillar GC.

17.
Cancers (Basel) ; 12(8)2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32759793

RESUMO

The Epstein-Barr virus (EBV), Kaposi sarcoma herpesvirus (KSHV) and human T-lymphotropic virus (HTLV-1) are lymphomagenic viruses with region-specific induced morbidity. The RIAL-CYTED aims to increase the knowledge of lymphoma in Latin America (LA), and, as such, we systematically analyzed the literature to better understand our risk for virus-induced lymphoma. We observed that high endemicity regions for certain lymphomas, e.g., Mexico and Peru, have a high incidence of EBV-positive lymphomas of T/NK cell origin. Peru also carries the highest frequency of EBV-positive classical Hodgkin lymphoma (HL) and EBV-positive diffuse large B cell lymphoma, not otherwise specified (NOS), than any other LA country. Adult T cell lymphoma is endemic to the North of Brazil and Chile. While only few cases of KSHV-positive lymphomas were found, in spite of the close correlation of Kaposi sarcoma and the prevalence of pathogenic types of KSHV. Both EBV-associated HL and Burkitt lymphoma mainly affect young children, unlike in developed countries, in which adolescents and young adults are the most affected, correlating with an early EBV seroconversion for LA population despite of lack of infectious mononucleosis symptoms. High endemicity of KSHV and HTLV infection was observed among Amerindian populations, with differences between Amazonian and Andean populations.

18.
J Med Virol ; 81(11): 1912-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19774688

RESUMO

Epstein-Barr virus genotypes can be distinguished by polymorphic variations in the genes encoding EBNA2, 3A, 3B, and 3C. The immediate early gene BZLF1 plays a key role in modulating the switch from latency to lytic replication and therefore enabling viral propagation. The aim of this study was to investigate and compare BZLF1 promoter sequence (Zp) variation in pediatric infectious mononucleosis (IM) and in pediatric EBV positive lymphoma biopsies. Zp was sequenced from peripheral blood mononuclear cells (PBMC) and throat swabs from 10 patients with IM at the time of diagnosis (D0) and during convalescence; and from 13 lymphoma biopsies. Zp - P and Zp - V3 variants were found in eight and one IM patients, as well as in five and six tumor biopsies, respectively. A correlation between viral genotype and Zp variant was found significant for Zp - V3 and EBV2 (P = 0.0002). One IM patient harbored two concomitant Zp variants. Regardless of anatomical compartment or stage of disease all IM patients displayed the same Zp variant along the course of the study. No new infections or adaptative selection of different variants was evidenced. A new Zp variant (Zp - V3 + 49) was described in two Hodgkin lymphomas, but not in IM. This is the first study to describe Zp variants compartmentalization in children with acute EBV infection and convalescence in a developing country; and comparing them with Zp variants in pediatric lymphomas from the same geographic area.


Assuntos
Herpesvirus Humano 4/genética , Mononucleose Infecciosa/virologia , Linfoma/virologia , Polimorfismo Genético , Regiões Promotoras Genéticas , Transativadores/genética , Adolescente , Biópsia , Criança , Pré-Escolar , Feminino , Genótipo , Herpesvirus Humano 4/isolamento & purificação , Humanos , Leucócitos Mononucleares/virologia , Masculino , Dados de Sequência Molecular , Faringe/virologia , Análise de Sequência de DNA
19.
Front Oncol ; 9: 881, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31620358

RESUMO

In classic Hodgkin lymphoma (cHL), Epstein Barr virus (EBV) association varies worldwide. Aims: Our aim was to analyze EBV association with pediatric cHL for the last 28 years. Methods: EBV presence was evaluated by EBERs in situ hybridization and LMP1 immunohistochemistry. Results: Until 2008, we found in pediatric cHL a similar percentage of EBV presence to those observed in adult cHL from developed populations. Nevertheless, in the last 8 years, an unexpected difference in cHL EBV association was proven, along with a slight bias of EBV association with the nodular sclerosis (NS) subtype. Concerning histological subtype distribution, even though MC still prevailed in the whole series, those cases diagnosed as NS showed a sustained rise from 1989 until today. Conclusion: Variations of EBV association of cHL related to geography, age, ethnicity, and histological type have been largely described when compared with different world regions, but interestingly, this single-center revised series brought to light the dynamic process behind the evolution of this relationship over time.

20.
Anticancer Agents Med Chem ; 19(6): 783-791, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30727915

RESUMO

BACKGROUND: The effect of estrogen has been traditionally studied through the modulation of its alpha and beta nuclear receptors; however, the G Protein-Coupled Estrogen Receptor (GPER) has been recently involved in the pathology of numerous tumors. Although the study of GPER in cervical cancer has begun, its contribution still remains to be completely evaluated. OBJECTIVE: The purpose of this work was to determine the expression of this receptor in different degrees of cervical lesions and whether the stimulation with its specific agonist (G-1) modulated mechanisms of cell survival or cell death in cervical cancer cells. METHODS: Sections of 44 formalin-fixed paraffin-embedded blocks from patients were analyzed by automated immunohistochemistry. After the stimulation with G-1, proliferation was evaluated by the xCELLigence technology, the integrity of the mitochondrial membrane permeability by MitoCaptureTM fluorescence staining, apoptosis by flow cytometry, and senescence by the senescence-associated ß-galactosidase kit. RESULTS: GPER was widely expressed in cervical cancer but not in its precursor lesions. The staining was predominantly cytoplasmic, although it was also important in the nucleus of the epithelial cells. G-1 inhibited proliferation, decreased the mitochondrial permeability, and increased the percentage of apoptosis in SiHa, HeLa, and C-33A. Only in C-33A, an increase of the cells in necrosis was observed, whereas SiHa was the only cell line in which senescence was evidenced. CONCLUSION: GPER is a receptor associated with cervical cancer that inhibits the growth and induces different mechanisms of death in cells derived from uterine cervical cancer. It suggests that GPER can be considered a pharmacological target that prevents the development of cervical carcinogenesis.


Assuntos
Receptores de Estrogênio/biossíntese , Receptores Acoplados a Proteínas G/biossíntese , Neoplasias do Colo do Útero/metabolismo , Apoptose , Morte Celular , Proliferação de Células , Células Cultivadas , Feminino , Humanos , Membranas Mitocondriais/metabolismo , Neoplasias do Colo do Útero/patologia
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