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Introduction: Although B-cell acute lymphoblastic leukemia (B-cell ALL) survival rates have improved in recent years, Hispanic children continue to have poorer survival rates. There are few tools available to identify at the time of diagnosis whether the patient will respond to induction therapy. Our goal was to identify predictive biomarkers of treatment response, which could also serve as prognostic biomarkers of death, by identifying methylated and differentially expressed genes between patients with positive minimal residual disease (MRD+) and negative minimal residual disease (MRD-). Methods: DNA and RNA were extracted from tumor blasts separated by immunomagnetic columns. Illumina MethlationEPIC and mRNA sequencing assays were performed on 13 bone marrows from Hispanic children with B-cell ALL. Partek Flow was used for transcript mapping and quantification, followed by differential expression analysis using DEseq2. DNA methylation analyses were performed with Partek Genomic Suite and Genome Studio. Gene expression and differential methylation were compared between patients with MRD-/- and MRD+/+ at the end of induction chemotherapy. Overexpressed and hypomethylated genes were selected and validated by RT-qPCR in samples of an independent validation cohort. The predictive ability of the genes was assessed by logistic regression. Survival and Cox regression analyses were performed to determine the association of genes with death. Results: DAPK1, BOC, CNKSR3, MIR4435-2HG, CTHRC1, NPDC1, SLC45A3, ITGA6, and ASCL2 were overexpressed and hypomethylated in MRD+/+ patients. Overexpression was also validated by RT-qPCR. DAPK1, BOC, ASCL2, and CNKSR3 can predict refractoriness, but MIR4435-2HG is the best predictor. Additionally, higher expression of MIR4435-2HG increases the probability of non-response, death, and the risk of death. Finally, MIR4435-2HG overexpression, together with MRD+, are associated with poorer survival, and together with overexpression of DAPK1 and ASCL2, it could improve the risk classification of patients with normal karyotype. Conclusion: MIR4435-2HG is a potential predictive biomarker of treatment response and death in children with B-cell ALL.
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Malignant pleural mesothelioma (MPM) is a rare and aggressive neoplasm of the pleural tissue that lines the lungs and is mainly associated with long latency from asbestos exposure. This tumor has no effective therapeutic opportunities nowadays and has a very low five-year survival rate. In this sense, identifying molecular events that trigger the development and progression of this tumor is highly important to establish new and potentially effective treatments. We conducted a meta-analysis of genome-wide expression studies publicly available at the Gene Expression Omnibus (GEO) and ArrayExpress databases. The differentially expressed genes (DEGs) were identified, and we performed functional enrichment analysis and protein-protein interaction networks (PPINs) to gain insight into the biological mechanisms underlying these genes. Additionally, we constructed survival prediction models for selected DEGs and predicted the minimum drug inhibition concentration of anticancer drugs for MPM. In total, 115 MPM tumor transcriptomes and 26 pleural tissue controls were analyzed. We identified 1046 upregulated DEGs in the MPM samples. Cellular signaling categories in tumor samples were associated with the TNF, PI3K-Akt, and AMPK pathways. The inflammatory response, regulation of cell migration, and regulation of angiogenesis were overrepresented biological processes. Expression of SOX17 and TACC1 were associated with reduced survival rates. This meta-analysis identified a list of DEGs in MPM tumors, cancer-related signaling pathways, and biological processes that were overrepresented in MPM samples. Some therapeutic targets to treat MPM are suggested, and the prognostic potential of key genes is shown.
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Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurales , Humanos , Mesotelioma/genética , Mesotelioma/metabolismo , Fosfatidilinositol 3-Quinasas , Neoplasias Pleurales/genética , Neoplasias Pleurales/metabolismo , Neoplasias Pulmonares/patologíaRESUMEN
Background: Gliomas represent almost 30% of all primary brain tumors and account for 80% of malignant primary ones. In the last two decades, significant progress has been made in understanding gliomas' molecular origin and development. These advancements have demonstrated a remarkable improvement in classification systems based on mutational markers, which contribute paramount information in addition to traditional histology-based classification. Methods: We performed a narrative review of the literature including each molecular marker described for adult diffuse gliomas used in the World Health Organization (WHO) central nervous system 5. Results: The 2021 WHO classification of diffuse gliomas encompasses many molecular aspects considered in the latest proposed hallmarks of cancer. The outcome of patients with diffuse gliomas relies on their molecular behavior and consequently, to determine clinical outcomes for these patients, molecular profiling should be mandatory. At least, the following molecular markers are necessary for the current most accurate classification of these tumors: (1) isocitrate dehydrogenase (IDH) IDH-1 mutation, (2) 1p/19q codeletion, (3) cyclin-dependent kinase inhibitor 2A/B deletion, (4) telomerase reverse transcriptase promoter mutation, (5) α-thalassemia/ mental retardation syndrome X-linked loss, (6) epidermal growth factor receptor amplification, and (7) tumor protein P53 mutation. These molecular markers have allowed the differentiation of multiple variations of the same disease, including the differentiation of distinct molecular Grade 4 gliomas. This could imply different clinical outcomes and possibly impact targeted therapies in the years to come. Conclusion: Physicians face different challenging scenarios according to the clinical features of patients with gliomas. In addition to the current advances in clinical decision-making, including radiological and surgical techniques, understanding the disease's molecular pathogenesis is paramount to improving the benefits of its clinical treatments. This review aims to describe straightforwardly the most remarkable aspects of the molecular pathogenesis of diffuse gliomas.
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Uveal melanoma (UVM) is a highly aggressive ocular cancer with limited therapeutic options and poor prognosis particularly for patients with liver metastasis. As such, the identification of new prognostic biomarkers is critical for developing effective treatment strategies. In this study, we aimed to investigate the potential of an ultraviolet light response gene signature to predict the prognosis of UVM patients. Our approach involved the development of a prognostic model based on genes associated with the cellular response to UV light. By employing this model, we generated risk scores to stratify patients into high- and low-risk groups. Furthermore, we conducted differential expression analysis between these two groups and explored the estimation of immune infiltration. To validate our findings, we applied our methodology to an independent UVM cohort. Through our study, we introduced a novel survival prediction tool and shed light on the underlying cellular processes within UVM tumors, emphasizing the involvement of immune subsets in tumor progression.
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Melanoma , Neoplasias de la Úvea , Humanos , Rayos Ultravioleta , Melanoma/patología , Neoplasias de la Úvea/genética , Neoplasias de la Úvea/metabolismo , Neoplasias de la Úvea/patología , Ojo/metabolismoRESUMEN
The bone marrow (BM) niche is a microenvironment where both immune and non-immune cells functionally interact with hematopoietic stem cells (HSC) and more differentiated progenitors, contributing to the regulation of hematopoiesis. It is regulated by various signaling molecules such as cytokines, chemokines, and adhesion molecules in its microenvironment. However, despite the strict regulation of BM signals to maintain their steady state, accumulating evidence in B-cell precursor acute lymphoblastic leukemia (BCP-ALL) indicates that leukemic cells can disrupt the physiological hematopoietic niche in the BM, creating a new leukemia-supportive microenvironment. This environment favors immunological evasion mechanisms and the interaction of these cells with the development and progression of BCP-ALL. With a growing understanding of the tumor immune microenvironment (TIME) in the development and progression of BCP-ALL, current strategies focused on "re-editing" TIME to promote antitumor immunity have been developed. In this review, we summarize how TIME cells are disrupted by the presence of leukemic cells, evading immunosurveillance mechanisms in the BCP-ALL model. We also explore the crosstalk between TIME and leukemic cells that leads to treatment resistance, along with the most promising immuno-therapy strategies. Understanding and further research into the role of the BM microenvironment in leukemia progression and relapse are crucial for developing more effective treatments and reducing patient mortality.
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Linfoma de Burkitt , Leucemia , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Humanos , Médula Ósea , Células Madre Hematopoyéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Moléculas de Adhesión Celular , Linfoma de Burkitt/patología , Leucemia/patología , Microambiente TumoralRESUMEN
Resumen El tratamiento para cáncer de próstata localizado (prostatectomía radical o radioterapia) ofrece unas altas tasas de curación; sin embargo, del 20 al 30% de los casos desarrollan recurrencia bioquímica. Actualmente, existen factores clínicos y patológicos que ayudan a predecir recurrencia; no obstante tanto el carácter heterogéneo de estos tumores, las diferencias en los tiempos de progresión de cáncer localizado a metastásico como la resistencia al tratamiento han dado lugar a imprecisiones en la predicción del pronóstico y a tratamientos insuficientes o excesivos. Debido a esto se han estudiado biomarcadores con el fin de estratificar más acertadamente el riesgo y mejorar las decisiones de tratamiento de una manera adecuada y oportuna. Este manuscrito presenta una revisión de marcadores moleculares de pronóstico que se han propuesto en los pacientes con cáncer de próstata localizado, lo que podría permitir establecer con mayor precisión el riesgo de recurrencia de la enfermedad.
Abstract Treatment for localised prostate cancer (radical prostatectomy or radiotherapy), offers high cure rates; nevertheless, 20% to 30% of the cases develop biochemical recurrence. There are clinical and pathological features that are currently being used to predict recurrence of the disease. However, tumour heterogeneity in prostate cancer, along with differences in time of progression to metastasis and treatment resistance, have led to inaccuracies in predicting the risk of biochemical relapse, and therefore, misleading in treatment decisions. Because of this, many genetic markers have been studied in order to refine risk stratification and improve treatment decisions in a suitable and opportune manner. This paper presents a review of molecular prognostic markers that have been proposed in patients with localised prostate cancer, which potentially could allow establishing the risk of recurrence of the disease more accurately.
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Humanos , Neoplasias de la Próstata , Biomarcadores , Marcadores Genéticos , Predicción , Metástasis de la NeoplasiaRESUMEN
Urine sampling for HPV DNA detection has been proposed as an effective method for monitoring the impact of HPV vaccination programs; however, conflicting results have been reported. The goal of this study was to evaluate the performance of optimized urine HPV DNA testing in women aged 19 to 25 years. Optimization process included the use of first void urine, immediate mixing of urine with DNA preservative, and the concentration of all HPV DNA, including cell-free DNA fragments. Urine and cervical samples were collected from 535 young women attending cervical screening at health centers from two Colombian cities. HPV DNA detection and genotyping was performed using an HPV type-specific multiplex genotyping assay, which combines multiplex polymerase chain reaction with bead-based Luminex technology. Concordance between HPV DNA detection in urine and cervical samples was determined using kappa statistics and McNemar tests. The accuracy of HPV DNA testing in urine samples was evaluated measuring sensitivity and specificity using as reference the results obtained from cervical samples. Statistical analysis was performed using STATA11.2 software. The findings revealed an overall HPV prevalence of 60.00% in cervical samples and 64.72% in urine samples, HPV-16 being the most frequent HPV type detected in both specimens. Moreover, our results indicate that detection of HPV DNA in first void urine provides similar results to those obtained with cervical samples and can be used to monitor HPV vaccination trials and programs as evidenced by the substantial concordance found for the detection of the four vaccine types. Cancer Prev Res; 9(9); 766-71. ©2016 AACR.
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Cuello del Útero/virología , ADN Viral/análisis , Tamizaje Masivo/métodos , Infecciones por Papillomavirus/diagnóstico , Orina/virología , Adulto , Colombia , Femenino , Humanos , Papillomaviridae , Infecciones por Papillomavirus/virología , Sensibilidad y Especificidad , Frotis Vaginal , Adulto JovenRESUMEN
Although high-risk human papillomaviruses (HPVs) are an important risk factor in the etiopathogenesis of cervical cancer, increasing evidence suggests that the ability to avoid immune surveillance seems to be linked to the transforming potential of HPV and a rapid progression to cancer. In other cancer models, IL-10 contributes to impair anti-tumor immune response either by downregulating human leukocyte antigen Class I (HLA-I) expression or by increasing HLA-G expression. To comprehend how these alterations could contribute to evasion of immune surveillance in cervical cancer, we analyzed HLA-I, HLA-G and IL-10 expressions by immunohistochemistry in 63 biopsies from patients with cervical intraepithelial neoplasia III (CIN-III) and cervical cancer. Immunohistochemistry showed absent or weak HLA-I expression in 50/59 cases. In these cases, a high percentage had loss of heterozygosis. IL-10 and HLA-G expression were observed in 46.6 and 27.6% of cases, respectively. Concurrent upregulation of IL-10 was found in 87.5% of HLA-G positive cases (p = 0.000). Similarly, a significant association between IL-10 expression and HLA-I downregulation was found (p = 0.028). Finally, we observed higher HLA-G expression in patients with HLA-I downregulation than in those with normal HLA-I expression (p = 0.004). Our results suggest that, in cervical cancer, the IL-10 expression may induce an immunosuppressive environment by upregulating HLA-G expression and downregulating HLA class I expression.
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Antígenos HLA-G/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Interleucina-10/metabolismo , Displasia del Cuello del Útero/inmunología , Neoplasias del Cuello Uterino/inmunología , Adulto , Femenino , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Persona de Mediana Edad , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/virología , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología , Displasia del Cuello del Útero/patología , Displasia del Cuello del Útero/virologíaRESUMEN
INTRODUCTION: Studies using Western Helicobacter pylori strains have shown that a risk factor for gastric cancer is the number of EPIYA-C motifs in the cytotoxin-associated A protein. CagA is delivered into epithelial cells, where it becomes tyrosine phosphorylated in their EPIYA repeats and induces cytoskeleton rearrangements. OBJECTIVES: The objective of this study was to evaluate H. pylori cagA positive strains isolated from Colombian patients with gastroduodenal diseases for the number of EPIYA-C repeats in cagA and their ability to induce cytoskeleton rearrangements in epithelial cells. MATERIALS AND METHODS: We analyzed the 3´ EPIYA repeats region of cagA by PCR in 93 H. pylori cagA positive strains from 49 patients with gastritis, 17 with gastric cancer, and 24 with duodenal ulcer. AGS cells exposed to the various H. pylori isolates were evaluated for rearrangements in their cytoskeleton. RESULTS: Strains with one EPIYA-C were the most frequent in gastritis and duodenal ulcer patients. Strains with three EPIYA-C were mainly found in gastric cancer. We found a significantly higher risk of gastric cancer for individuals infected with strains harboring three EPIYA-C motifs (OR=12.4, CI95%: 2.32-66.3). Strains from gastric cancer showed significantly higher percentages of induction of cytoskeleton rearrangements in comparison with those from gastritis (p Mann-Whitney<0.005). CONCLUSIONS: H. pylori strains with three EPIYA-C repeats can confer an increased risk of cancer to infected individuals.
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Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Helicobacter pylori/genética , Adulto , Anciano , Colombia , Células Epiteliales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Estómago/citología , Adulto JovenRESUMEN
Introduction. Studies using Western Helicobacter pylori strains have shown that a risk factor for gastric cancer is the number of EPIYA-C motifs in the cytotoxin-associated A protein. CagA is delivered into epithelial cells, where it becomes tyrosine phosphorylated in their EPIYA repeats and induces cytoskeleton rearrangements. Objectives. The objective of this study was to evaluate H. pylori cagA positive strains isolated from Colombian patients with gastroduodenal diseases for the number of EPIYA-C repeats in cagA and their ability to induce cytoskeleton rearrangements in epithelial cells. Materials and methods. We analyzed the 3 EPIYA repeats region of cagA by PCR in 93 H. pylori cagA positive strains from 49 patients with gastritis, 17 with gastric cancer, and 24 with duodenal ulcer. AGS cells exposed to the various H. pylori isolates were evaluated for rearrangements in their cytoskeleton. Results. Strains with one EPIYA-C were the most frequent in gastritis and duodenal ulcer patients. Strains with three EPIYA-C were mainly found in gastric cancer. We found a significantly higher risk of gastric cancer for individuals infected with strains harboring three EPIYA-C motifs (OR=12.4, CI95%: 2.32-66.3). Strains from gastric cancer showed significantly higher percentages of induction of cytoskeleton rearrangements in comparison with those from gastritis (p Mann-Whitney<0.005). Conclusions. H. pylori strains with three EPIYA-C repeats can confer an increased risk of cancer to infected individuals.
Introducción. En los aislamientos de Helicobacter pylori del hemisferio occidental, se ha observado que el número de repeticiones EPIYA-C en la proteína CagA es un factor de riesgo para cáncer gástrico. La proteína CagA es introducida en la célula epitelial y, posteriormente, es fosforilada en las tirosinas presentes en los motivos EPIYA e induce rearreglos en el citoesqueleto. Objetivos. Nuestro propósito fue evaluar el número de repeticiones EPIYA-C y la habilidad para inducir rearreglos en el citoesqueleto en los aislamientos de H. pylori positivos para cagA, provenientes de pacientes colombianos con enfermedad gastroduodenal. Materiales y métodos. Mediante PCR, se analizó la región 3´ que contiene las repeticiones EPIYA-C, en 93 aislamientos de H. pylori positivos para cagA provenientes de 49 pacientes con gastritis, 17 con cáncer gástrico y 24 con úlcera duodenal. Los rearreglos del citoesqueleto se evaluaron mediante cultivos simultáneos de células AGS con las cepas de H. pylori.Resultados. En gastritis y úlcera duodenal se observó la mayor frecuencia de aislamientos con EPIYA C; los aislamientos con tres repeticiones EPIYA-C se encontraron con mayor frecuencia en cáncer gástrico. Encontramos un riesgo de cáncer gástrico significativamente mayor para individuos infectados con cepas con tres repeticiones EPIYA-C (OR=12,4; IC95% 2,32-66,3). Los aislamientos provenientes de cáncer gástrico mostraron mayores porcentajes de inducción de rearreglos en el citoesqueleto que los observados con aislamientos provenientes de gastritis (prueba de Mann-Whitney menor de 0,005). Conclusiones. La infección con cepas de H. pylori con tres repeticiones EPIYA-C puede conferir un mayor riesgo de desarrollar cáncer gástrico.
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Gastritis , Helicobacter pylori , Polimorfismo Genético , Úlcera Duodenal , Neoplasias GástricasRESUMEN
Objetivo: Caracterizar la respuesta IgG e IgA hacia VLP (partículas semejantes a virus) del virus del papiloma humano (VPH) 16, 31 y 58 y determinar su asociación con la eliminación de la infección. Métodos: Se incluyeron 186 mujeres con citología normal participantes en un estudio de cohorte sobre la historia natural de la infección por VPH. Se evaluaron tres grupos: control (negativas para ADN VPH, n=146), eliminación (positivas al ingreso y negativas durante el seguimiento, n=25) y persistencia (positivas durante el seguimiento, n=15). Los anticuerpos IgG e IgA hacia VLP VPH 16, 31 y 58 se analizaron mediante ELISA. Resultados: En la primera visita, se observó en el grupo de eliminación una mayor seroprevalencia de anticuerpos IgG hacia VLP VPH 16. Esta prevalencia estuvo acompañada de mayores niveles de anticuerpos en este grupo, en comparación con los niveles observados en el grupo de persistencia (media DO405 nm 0,665 vs. 0,290, respectivamente). En contraste, en la quinta visita, se observó una mayor seroprevalencia de anticuerpos IgG hacia VLP VPH 16 y 58 en el grupo de persistencia (p=0,001 y p=0,003, respectivamente). Esta respuesta se correlacionó con mayores niveles de anticuerpos en esta visita (media DO405 nm 0,653 y 0,532, respectivamente), en comparación con los niveles de anticuerpos observados en la primera visita (media DO405 nm 0,290 y 0,362, respectivamente). Conclusiones: La presencia de altos niveles de anticuerpos IgG hacia VPH 16 y 58 durante la infección podría estar asociada con la eliminación de la infección.
Objective: To profile IgG and IgA response to the VLP ( virus-like particles) of the human papillomaviruses (HPV) 16, 31 and 58 and to assess the possibility that they may be related to eliminating infection. Methods: A group of 186 women with normal cytology, participants in a cohort study on the natural history of HPV infection, were selected. Three groups were evaluated: control (DNA HPV, n=146 negative), elimination (positive at outset and negative during follow-up, n=25), and persistance (positive during follow-up, n=15). The IgG and IgA antibodies against HPV-VLP 16, 31, and 58 were submitted to ELISA analysis. Results: During the initial visit greater IgG antibody seroprevalence against HPV16-VLP was observed among the elimination group. This prevalence was combined with greater antibody levels in this group in comparison with the levels found among members of the persistence (mean DO405 nm 0.665 vs. 0.290, respectively). In contrast, during the fifth visit, there was greater IgG antibody seroprevalence against HPV-PLV 16 and 58 among the persistance group (p=0.001 and p=0.003, respectively). This response correlated with greater anitbody levels on this visit (mean DO 405 nm 0.653 and 0.532, respectively) in comparison with the antibody levels observed on the first visit (mean DO 405 nm 0.290 and0.362, respectively). Conclusion: High levels of IgG antibodies working against HPV 16 and 58 during infection phase may be associated with elimination of infection.
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Humanos , Adulto , Femenino , Anciano , Estudios de Casos y Controles , Antígenos HLA-D , Inmunoglobulina A , Inmunoglobulina G , Control de Infecciones , Neoplasias del Cuello Uterino , Colombia , Ensayo de Inmunoadsorción Enzimática/métodos , Reacción en Cadena de la Polimerasa/métodosRESUMEN
Objetivo: Examinar la asociación entre la respuesta celular anti-VPH y la expresión de HLA clase I, HLA-G e IL-10 en céluals tumorales. Materiales y métodos: Linfocitos fueron aislados de 18 pacientes con CCU y estimulados con células dendríticas pulsadas con la proteína E7VPH-16 o directamente con péptidos sintéticos: E751-70´E765-84yE779-98. La células fueron marcadas para CD4,CD69, citoquinas intracelulares IFN-y e IL-4 y analizadas por citometría. La expresión de HLA-G e IL-10 fue analizada por inmunohistoquimica. Resultados: Una pérdida total de la expresión de HLA clae I se observó en 11/18 y regulación negativamente en 4/18 pacientes. La expresión HLA-G se observó EN 11/18 y regulación negativamente en 4/18 pacientes mientras que la expresión IL-10 en 6/17 pacientes. Se observó una asociación inversa entre la expresión de IL-10 y la falta de una respuesta inmune especifica (p=0.041). Ninguna asociación fue observada entre la expresión de HLA clase I o la expresión de HLA-G con la respuesta inmune. Conclusiones: Nuestros resultados subrayan la importancia de otros factores inmunes, como la expresión de IL-10, que podrían influir en la respuesta antitumoral. Estos resultados pueden tener implicaciones importantes durante el desarrollo de nuevas estrategias inmunoterapéuticas.
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Cuello del Útero , Antígenos HLA , Neoplasias , Linfocitos T , Escape del TumorRESUMEN
BACKGROUND: The hepatitis C virus (HCV) commonly causes persistent infection. One of the viral mechanisms in preventing viral clearance is the ability of HCV to induce functional alterations of the immune system cells, specifically of dendritic cells. Viral proteins producing the dendritic cell functional alterations have been identified as the HCV core protein, which makes up the capsid structural unit. OBJECTIVE: One of the limitations to evaluate core protein properties is the difficulty in obtaining and purifying the complete protein--consisting of 191 amino acids. The aim of the current study was to produce and purify the recombinant core protein in a eukaryotic system, and to evaluate its effect in human dendritic cell cultures. RESULTS: The core protein p23 isoform was expressed in a baculovirus system and purified using isoelectric point separation and electroelution. The purity of the core protein was confirmed by silver stain and Western blot. These analyses showed the presence of two bands that correspond to p23 and p21 isoforms of core protein as previously reported. CONCLUSION: The expressed protein differed from naive core protein is terms of molecular weight, isoforms and subcellular localization. The procedures developed for core protein are applicable for expression of other membrane-associated proteins produced in eukaryotic systems.
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Hepacivirus/genética , Hepatitis C/genética , Proteínas del Núcleo Viral/biosíntesis , Baculoviridae/química , Bioensayo , Western Blotting , Proteínas de la Cápside/biosíntesis , Proteínas de la Cápside/genética , Hepacivirus/fisiología , Hepatitis C/fisiopatología , Humanos , Proteínas del Núcleo Viral/genéticaRESUMEN
Introducción. La infección por el virus de la hepatitis C (VHC) se caracteriza por la alta frecuencia de infección persistente. La capacidad del VHC para inducir alteraciones en la función de las células del sistema inmune, específicamente en las células dendríticas, parece ser una de las estrategias virales implicada en el establecimiento de la infección persistente. Esta estrategia parece estar mediada en gran parte por una de las proteínas estructurales codificada por el genoma del VHC, la proteína Core, unidad estructural de la cápside viral. Objetivo. Una de las limitantes para la evaluación de las propiedades de Core es la obtención y la purificación de la proteína nativa (191 aa). El objetivo de este estudio fue la producción y la purificación de la proteína Core completa en un sistema eucariote para evaluar las propiedades de la proteína en cultivos de células dendríticas humanas. Resultados. En este estudio se logró la producción de la proteína Core completa en el sistema de expresión de baculovirus y su purificación por la técnica de separación por punto isoeléctrico y electroelución. La pureza de la proteína obtenida se confirmó por Western blot y tinción con plata. Estos análisis mostraron dos bandas únicas correspondientes a las isoformas p23 y p21 de la proteína Core, previamente descritas en la literatura. Conclusiones. La proteína obtenida posee varias de las condiciones de la proteína Core nativa, como peso molecular, isoformas y localización subcelular. Los procedimientos descritos en este artículo son aplicables a proteínas asociadas a membranas producidas en sistemas de expresión eucarióticos
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Baculoviridae , Hepacivirus , Focalización Isoeléctrica , Proteínas de la Cápside/aislamiento & purificación , BioensayoRESUMEN
Introducción: En Colombia, el carcinoma de cérvix es la primera causa de muerte por cáncer de la mujer en edad reproductiva.Se ha demostrado una asociación etiológica entre los virus del papiloma humano (HPV) de alto riesgo y esta neoplasia. La proteína L1 de los HPV tiene la propiedad de autoensamblarse en cápsides vacías(VLP). En varios estudios basados en VLP DE hpv16 o HPV18 se ha observado que la infección por HPV genitales es seguida por una respuesta serológica o proteínas de la cápside. Objetivos: Evaluar la respuesta serológica hacia las VLP de los tipos virales oncogénicos 16,18,31,33,39,58 y 59 en mujeres colombianas con cáncer de cérvix, y en controles y compararlos con la presencia de ADN viral, la edad y el curso clínico. Materiales y Métodos: Se analizó la presencia de anticuerpos hacia las VLP de 7 tipos virales oncogénicos en 147 sueros de mujeres con citología normal apareados por edad, mediante ELISA. Resultados: Se detectaron anticuerpos anti-VLP en 82 por ciento de pacientes y en 56 por ciento de controles. La detección de anticuerpos contra múltiples tipos de HPV fue la regla; en pacientes jóvenes con cáncer de cérvix se observaron altos nivels de anticuerpos. En los casos con seguimiento serológico durante un año, en general, los anticuerpos se mantuvieron en el mismo nivel; sin embargo, en algunos hubo elevación o disminución simultánea de los anticuerpos contra varios tipos virales. Conclusiones:Nuestros resultados confirman (i) la alta tasa de infecciones por HPV en Colombia, tanto en pacientes con cáncer como entre población general, y las particularmente altas tasas de infección por los tipos virales 31 y 58,(ii) la validez de los anticuerpos anti-VLP como marcadores de infecciones en curso o pasadas. La aparición o desaparición simultánea de anticuerpos contra VLP de varios tipos virales sugiere que los anticuerpos detectados en ELISA no son siempre tipoespecíficos.
Asunto(s)
Anticuerpos , Sondas de ADN de HPV , Neoplasias del Cuello UterinoRESUMEN
Los efectos de la infección por HPV en la sensibilidad intrínseca de la célula tumoral a la radioterapí (RT) no son claros.Anticuerpos hacia la oncoproteína viral E7 son detectados de manera consistente en pacientes con cáncer de cérvix; .El Propósito de este estudio fue evaluar la presencia de DNA de HPV y anticuerpos hacia E7 del HPV16 como marcadores potenciales de pronóstico en carcinoma de cérvix.Se incluyeron 58 pacientes con diagnóstico de carcinoma cervical, estadios FIGO IIB y IIIB. Se tomaron muestras de sangre y cepillados cervicales antes de la RT 2 y 6-12 meses después. El DNA de HPV fue detectado por PCR, y los anticuerpos anti E7 fueron medidos por ELISA usando como blancos antigénicos una proteína recombinante de fusión MBP-E7 y dos péptidos sintéticos E7(a.a 1-20) y E7(a.a 66-85). El tiempo medio de seguimiento de las pacientes fue de 35 meses (rango: 2-65 meses). se hizo un análisis univariaado para determinar la significancia estadística de los factores relacionados con el pronóstico.Antes de la radioterapia se detectó DNA de HPV en un 18 por ciento de los casos. No se observaron asociaciones significativas entre el estado viral antes de RT y estadio FIGO, tamaño tumoral o tipo histológico.La presencia de HPV antes de RT y la eliminación del virus después RT se asociaron con un mejor pronóstico: la supervivencia global a 5 años fue del 65,9 por ciento para las pacientes positivas para HPV antes de RT versus el 36.3 por ciento para las pacientes negativas (p=0,038).Se observó una disminución estadísticamente significativa en la detección genérica de DNA de HPV después de la radioterapía. Después de la radioterapía. Después de tres meses 19 pacientes permanecieron poisitivos (p<10-4),después de 6-12 meses, 8 pacientes aún portaban DNA de HPV (p<10-4). La supervivencia global fue del 36 por ciento para pacientes con persistencia viral versus el 75 por ciento para las pacientes en las que el virus fue eliminado luego de la RT (p=0,002).Se detectaron anticuerpos hacia MBP-E7 en el 56,1 por ciento de pacientes, hacia E7(1-20 en el 26,3 por ciento y hacia E7(66-85) en el 31,6 por ciento.Los niveles de anticuerpos hacia la proteína E7 de HPV16 y la detección de HPV antes del tratameinto y en el seguimiento podrían tener una utilidad clínica en el manejo diferencial de las pacientes con carcinoma de cuello uterino localmente avanzado, con miras a una mayor sobrevida.
Asunto(s)
Sondas de ADN de HPV , Análisis de Secuencia de ADN , Neoplasias del Cuello UterinoRESUMEN
The neutralizing activities of polyclonal antibodies and monoclonal antibodies (MAbs) obtained by immunization of mice with L1 virus-like particles (VLPs) were investigated by using pseudovirion infectivity assays for human papillomavirus type 16 (HPV-16), HPV-31, HPV-33, HPV-45, HPV-58, and HPV-59 to obtain a better definition of cross-neutralization between high-risk HPVs. In this study, we confirmed and extended previous studies indicating that most genital HPV genotypes represent separate serotypes, and the results suggest that the classification of serotypes is similar to that of genotypes. In addition, three cross-neutralizing MAbs were identified (HPV-16.J4, HPV-16.I23, and HPV-33.E12). MAb HPV-16.J4 recognized a conserved linear epitope located within the FG loop of the L1 protein, and HPV-16.I23 recognized another located within the DE loop. The results suggested that reactivity of MAb HPV-16.I23 to L1 protein is lost when leucine 152 of the HPV-16 L1 protein is replaced by phenylalanine. This confirmed the existence of linear epitopes within the L1 protein that induce neutralizing antibodies, and this is the first evidence that such linear epitopes induce cross-neutralization. However, the cross-neutralization induced by L1 VLPs represents less than 1% of the neutralizing activity induced by the dominant conformational epitopes, and it is questionable whether this is sufficient to offer cross-protection in vivo.
Asunto(s)
Anticuerpos Monoclonales/inmunología , Cápside/inmunología , Mapeo Epitopo , Proteínas Oncogénicas Virales/inmunología , Papillomaviridae/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Antivirales/inmunología , Cápside/química , Reacciones Cruzadas , Epítopos/inmunología , Humanos , Inmunización , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Pruebas de Neutralización , Proteínas Oncogénicas Virales/química , Papillomaviridae/clasificación , Virión/inmunologíaRESUMEN
BACKGROUND: Cervical cancer is the most common cancer in women in Mali and the second commonest cause of cancer mortality. METHODS: As part of an international effort to evaluate the role of human papillomavirus (HPV) in the aetiology of cervical cancer, we conducted a hospital-based case-control study in three medical centres in Bamako during 1994-1995. A total of 82 cases (invasive cervical cancer patients) and 97 controls matched to the cases for age were included. Information on risk factors was collected through personal interview. Serum antibodies to HPV 16, 18 and 31 virus like particles (VLP) were detected using ELISA assays. Polymerase chain reaction was used to detect HPV DNA in frozen biopsies of cases. RESULTS: Human papillomavirus 6, 18, 31 VLP were detected in 60.4% of cases and 45.4% of controls (P = 0.03). Overall, HPV DNA was identified in 96.9% of the cervical cancer cases. Risk factors for cervical cancer were parity >10 versus <5 children ([odds ratio] OR = 4.8, 95% CI : 1.5-14.7), never having practised vaginal douching (OR = 17.6, 95% CI : 4.2-74.7), re-using home-made feminine napkins (OR = 45.9, 95% CI : 8.8-238.7) and having a husband with more than two wives (OR = 5.3, 95% CI : 1.3-21.3). CONCLUSIONS: These data provide further evidence on the role of HPV in cervical cancer and show that high parity and poor genital hygiene conditions were the main co-factors for cervical cancer in this population with prevalent HPV infection.
Asunto(s)
Neoplasias del Cuello Uterino/epidemiología , Adulto , Estudios de Casos y Controles , Circuncisión Femenina , Femenino , Humanos , Higiene , Malí/epidemiología , Persona de Mediana Edad , Papillomaviridae , Infecciones por Papillomavirus/epidemiología , Paridad , Factores de Riesgo , Conducta Sexual , Factores Socioeconómicos , Infecciones Tumorales por Virus/epidemiología , Neoplasias del Cuello Uterino/virologíaRESUMEN
The serologic response against virus-like particles (VLP) from 7 high risk genital papillomaviruses was investigated by ELISA in 147 Colombian women with invasive cervical cancer and 147 age-matched cytologically normal and HPV-DNA negative women. Anti-VLP antibodies were detected in 82% of the invasive cervical cancer patients and in 56% of the controls. Detection of antibodies against multiple HPV types is the rule and the presence of high antibody titers was associated with higher survival of cancer patients. Higher anti-VLP seroprevalence was observed in younger cancer patients. In those followed serologically for 1 year, antibodies generally remained at the same level. However, in some patients an increase or decrease in antibody levels occurred simultaneously for multiple HPV types, suggesting cross-reactivity between the HPV types investigated. Investigation of seroreactivity between 8 high risk HPVs suggested that there is some cross-reactivity between phylogeneticaly-related types such as 16, 31, 33 and 58; and 18, 45 and 59. In conclusion, our results confirmed (i) the high rate of HPV infections in Colombia, both in patients with cervical cancer and in the general population, and the particularly high rate of infections due to HPV 31 and 58; and (ii) the validity of anti-VLPs as a marker of present or past HPV infection. The simultaneous appearance or disappearance of antibodies against multiple HPV VLPs suggests that the antibodies detected by ELISA are not always type specific.
Asunto(s)
Adenocarcinoma/virología , Carcinoma de Células Escamosas/virología , Papillomaviridae/inmunología , Infecciones por Papillomavirus/inmunología , Infecciones Tumorales por Virus/inmunología , Neoplasias del Cuello Uterino/virología , Adenocarcinoma/epidemiología , Adenocarcinoma/inmunología , Adulto , Anciano , Anticuerpos Antivirales/sangre , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/inmunología , Estudios de Casos y Controles , Colombia/epidemiología , ADN Viral/análisis , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Persona de Mediana Edad , Papillomaviridae/clasificación , Papillomaviridae/genética , Infecciones por Papillomavirus/epidemiología , Reacción en Cadena de la Polimerasa , Estudios Seroepidemiológicos , Infecciones Tumorales por Virus/epidemiología , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/inmunologíaRESUMEN
The major structural protein (VP1) of the BK polyomavirus (BKV) was expressed in the recombinant baculovirus expression system. Recombinant BKV VP1 was shown to self-assemble into virus-like particles (VLPs) with a diameter of 45-50 nm. As for other polyomaviruses, BKV VP1 has the capacity to bind to exogenous DNA. Furthermore, the potential of BKV VP1 VLPs was investigated for gene transfer into COS-7 cells using three methods for the formation of pseudo-virions: disassembly/reassembly, osmotic shock and direct interaction between VLPs and reporter plasmid DNA. The latter method was shown to be the most efficient when using linearized plasmid. Gene transfer efficiency with BKV pseudo-virions was of the same order as that observed with human papillomavirus type 16 L1 protein VLPs. In addition, it is demonstrated that cellular entry of BKV pseudo-virions is dependent on cell surface sialic acid.