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1.
Sensors (Basel) ; 23(4)2023 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-36850360

RESUMEN

The automotive industry is experiencing a transformation with the rapid integration of software-based systems inside vehicles, which are complex systems with multiple sensors. The use of vehicle sensor data has enabled vehicles to communicate with other entities in the connected vehicle ecosystem, such as the cloud, road infrastructure, other vehicles, pedestrians, and smart grids, using either cellular or wireless networks. This vehicle data are distributed, private, and vulnerable, which can compromise the safety and security of vehicles and their passengers. It is therefore necessary to design an access control mechanism around the vehicle data's unique attributes and distributed nature. Since connected vehicles operate in a highly dynamic environment, it is important to consider context information such as location, time, and frequency when designing a fine-grained access control mechanism. This leads to our research question: How can Attribute-Based Access Control (ABAC) fulfill connected vehicle requirements of Signal Access Control (SAC), Time-Based Access Control (TBAC), Location-Based Access Control (LBAC), and Frequency-Based Access Control (FBAC)? To address the issue, we propose a data flow model based on Attribute-Based Access Control (ABAC) called eXtensible Access Control Markup Language for Mobility (XACML4M). XACML4M adds additional components to the standard eXtensible Access Control Markup Language (XACML) to satisfy the identified requirements of SAC, TBAC, LBAC, and FBAC in connected vehicles. Specifically, these are: Vehicle Data Environment (VDE) integrated with Policy Enforcement Point (PEP), Time Extensions, GeoLocation Provider, Polling Frequency Provider, and Access Log Service. We implement a prototype based on these four requirements on a Raspberry Pi 4 and present a proof-of-concept for a real-world use case. We then perform a functional evaluation based on the authorization policies to validate the XACML4M data flow model. Finally, we conclude that our proposed XACML4M data flow model can fulfill all four of our identified requirements for connected vehicles.

2.
J Biol Chem ; 297(2): 100928, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34274316

RESUMEN

B-cell lymphoma 6 (BCL6) is a zinc finger transcriptional repressor possessing a BTB-POZ (BR-C, ttk, and bab for BTB; pox virus and zinc finger for POZ) domain, which is required for homodimerization and association with corepressors. BCL6 has multiple roles in normal immunity, autoimmunity, and some types of lymphoma. Mice bearing disrupted BCL6 loci demonstrate suppressed high-affinity antibody responses to T-dependent antigens. The corepressor binding groove in the BTB-POZ domain is a potential target for small compound-mediated therapy. Several inhibitors targeting this binding groove have been described, but these compounds have limited or absent in vivo activity. Biophysical studies of a novel compound, GSK137, showed an in vitro pIC50 of 8 and a cellular pIC50 of 7.3 for blocking binding of a peptide derived from the corepressor silencing mediator for retinoid or thyroid hormone receptors to the BCL6 BTB-POZ domain. The compound has good solubility (128 µg/ml) and permeability (86 nM/s). GSK137 caused little change in cell viability or proliferation in four BCL6-expressing B-cell lymphoma lines, although there was modest dose-dependent accumulation of G1 phase cells. Pharmacokinetic studies in mice showed a profile compatible with achieving good levels of target engagement. GSK137, administered orally, suppressed immunoglobulin G responses and reduced numbers of germinal centers and germinal center B cells following immunization of mice with the hapten trinitrophenol. Overall, we report a novel small-molecule BCL6 inhibitor with in vivo activity that inhibits the T-dependent antigen immune response.


Asunto(s)
Proteínas Proto-Oncogénicas c-bcl-6 , Animales , Linfocitos B/metabolismo , Humanos , Ratones , Transcripción Genética , Dedos de Zinc
3.
Reg Environ Change ; 21(3): 84, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34456624

RESUMEN

Flood events in West Africa have devastating impacts on the lives of people. Additionally, developments such as climate change, settlement expansion into flood-prone areas, and modification of rivers are expected to increase flood risk in the future. Policy documents have issued calls for conducting local risk assessments and understanding disaster risk in diverse aspects, leading to an increase in such research. Similarly, in a shift from flood protection to flood risk management, the consideration of various dimensions of flood risk, the necessity of addressing flood risk through an integrated strategy containing structural and non-structural measures, and the presence of residual risk are critical perspectives raised. However, the notion of "residual risk" remains yet to be taken up in flood risk management-related academic literature. This systematic review seeks to approach the notion of residual risk by reviewing information on flood impacts, common measures, and recommendations in academic literature. The review reveals various dimensions of impacts from residual flood risk aside from material damage, in particular, health impacts and economic losses. Infrastructural measures were a dominant category of measures before and after flood events and in recommendations, despite their shortcomings. Also, spatial planning interventions, a more participatory and inclusive governance approach, including local knowledge, sensitisation, and early warning systems, were deemed critical. In the absence of widespread access to insurance schemes, support from social networks after flood events emerged as the most frequent measure. This finding calls for in-depth assessments of those networks and research on potential complementary formal risk transfer mechanisms. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10113-021-01826-7.

4.
J Cell Mol Med ; 24(19): 11573-11582, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32858764

RESUMEN

The IKK-related kinases, IKKε and TBK1, have essential roles in innate immunity in part through modifying MYD88 signalling from the Toll-like receptors to regulate NF-κB signalling. We investigated the expression and function of IKKε and TBK1, in diffuse large B-cell lymphoma (DLBCL). DLBCL cell lines and patient-derived xenografts were used to determine their sensitivity to IKKε and TBK1 inhibitors. To understand the function of IKKε and TBK1 secreted factors were determined following administration of inhibitors. Gene expression microarrays were used to determine the transcriptional effects of inhibitors. Higher TBK1 mRNA levels associated with poorer clinical outcome but IKKε and TBK1 were expressed in both germinal centre and non-germinal centre types of DLBCL. Survival of cell lines Ly10, Ly03 and Pfeiffer, and of some primary human lymphoma cells, was suppressed by a small molecule IKKε/TBK1 inhibitor, DMX3433. DMX3433 reduced IL-10 production from Ly10 and repressed NF-κB mediated transcription. Inhibition of IKKε and TBK1 warrants further investigation as a potential therapeutic route to suppress NF-κB signalling in lymphoma.


Asunto(s)
Quinasa I-kappa B/metabolismo , Interleucina-10/metabolismo , Linfoma de Células B Grandes Difuso/metabolismo , FN-kappa B/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Animales , Línea Celular Tumoral , Quimiocinas/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Quinasa I-kappa B/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/patología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/farmacología , Factor de Transcripción ReIA/metabolismo
5.
Br J Haematol ; 189(1): 54-66, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32064593

RESUMEN

Peripheral T-cell lymphomas (PTCL) comprise a heterogeneous group of aggressive lymphoproliferative disorders almost all of which are associated with poor clinical outcomes. Angioimmunoblastic T-cell lymphoma (AITL) and some peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) have similarities to normal CD4+ T-cell subsets in their gene expression profiles. A cell of origin model is, therefore, emerging and is likely to be refined in the future. Follicular helper (Tfh) T cells are now established as the cell of origin of AITL and about 20% of PTCL-NOS. Sequencing studies have identified recurrent genetic alterations in epigenetic modifiers, T-cell receptor signalling pathway intermediates or RHOA, most commonly a specific mutation leading to RHOA G17V. While PTCL-NOS remains a diagnosis of exclusion, advances in genomics have identified subgroups expressing transcription factors TBX 21 (Th1-like origin) and GATA3 (Th2-like origin). These findings suggest new biomarkers and new therapeutic avenues including the hypomethylating agent azacytidine, or inhibitors of proximal T-cell receptor (TCR) signalling and potentially certain monoclonal antibodies. The advances over the past few years, therefore, prompt stratified medicine approaches to test biologically based treatments and determine the clinical utility of the new disease classifications.


Asunto(s)
Epigénesis Genética/inmunología , Regulación Neoplásica de la Expresión Génica/inmunología , Linfoma de Células T Periférico , Mutación Missense , Proteínas de Neoplasias , Linfocitos T Colaboradores-Inductores/inmunología , Proteína de Unión al GTP rhoA , Humanos , Linfoma de Células T Periférico/clasificación , Linfoma de Células T Periférico/genética , Linfoma de Células T Periférico/inmunología , Linfoma de Células T Periférico/terapia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/inmunología , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología , Transducción de Señal/genética , Transducción de Señal/inmunología , Proteína de Unión al GTP rhoA/genética , Proteína de Unión al GTP rhoA/inmunología
6.
J Cell Mol Med ; 23(1): 340-348, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30353642

RESUMEN

CUDC-907, a dual PI3K/HDAC inhibitor, has been proposed to have therapeutic potential in hematopoietic malignancies. However, the molecular mechanisms of its effects in chronic lymphocytic leukaemia (CLL) remain elusive. We show that CLL cells are sensitive to CUDC-907, even under conditions similar to the protective microenvironment of proliferation centres. CUDC-907 inhibited PI3K/AKT and HDAC activity, as expected, but also suppressed RAF/MEK/ERK and STAT3 signalling and reduced the expression of anti-apoptotic BCL-2 family proteins BCL-2, BCL-xL, and MCL-1. Moreover, CUDC-907 downregulated cytokines BAFF and APRIL and their receptors BAFFR, TACI, and BCMA, thus blocking BAFF-induced NF-κB signalling. T cell chemokines CCL3/4/17/22 and phosphorylation of CXCR4 were also reduced by CUDC-907. These data indicated that CUDC-907 abrogates different protective signals and suggested that it might sensitize CLL cells to other drugs. Indeed, combinations of low concentrations of CUDC-907 with inhibitors of BCL2, BTK, or the NF-κB pathway showed a potent synergistic effect. Our data indicate that, apart from its known functions, CUDC-907 blocks multiple pro-survival pathways to overcome microenvironment protection in CLL cells. This provides a rationale to evaluate the clinical relevance of CUDC-907 in combination therapies with other targeted inhibitors.


Asunto(s)
Antineoplásicos/farmacología , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/patología , Morfolinas/farmacología , Pirimidinas/farmacología , Factor Activador de Células B/metabolismo , Supervivencia Celular/efectos de los fármacos , Quimiocinas/metabolismo , Humanos , Leucemia Linfocítica Crónica de Células B/metabolismo , FN-kappa B/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Receptores CXCR4/metabolismo , Transducción de Señal/efectos de los fármacos , Células Tumorales Cultivadas , Microambiente Tumoral/efectos de los fármacos , Miembro 13 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/metabolismo
7.
Br J Haematol ; 184(6): 957-968, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30548597

RESUMEN

Delayed lymphocyte and T-cell immune reconstitution following bendamustine-rituximab (BR) for indolent non-Hodgkin lymphoma (iNHL) has been described, but no information is available for chronic lymphocytic leukaemia (CLL). We present a population-based retrospective analysis of immune reconstitution and risk of infection following BR. Outcomes included timing/correlates of CD4+ recovery and risk of ≥grade 3 infections. Consecutively treated patients (1 April 2014 to 31 January 2017) were included (n = 295),with a median age of 65 years (range 33-92); 57% were 1st line treatments. Median cumulative bendamustine dose was 1080 mg/m2 (range 140-1440 mg/m2 ). CD4/CD8/CD19/NK subsets were available for 148 patients. Median follow-up was 24 months. Median times to lymphocyte count (ALC) recovery (≥1 × 109 /l) and CD4+ recovery (≥0·2 × 109 /l) were 26 and 24 months, respectively. Bendamustine total dose >1080 mg/m2 (hazard ratio [HR] 0·4; 95% confidence interval [CI]: 0·2-0·8), end-of-treatment ALC ≤0·4 × 109 /l (HR 0·53; 95% CI: 0·3-0·9) and CD4+ <0·1 × 109 /l 1-year post-BR (HR 0·03; 95% CI: 0·008-0·15) were covariables for delayed CD4+ recovery. ALC-recovery ≥1 × 109 /l was an unreliable predictor of CD4+ recovery (negative predictive vale 74%, positive predictive value 86%, likelihood ratio 3·3). CD4+ lymphopenia >3 years was a significant risk factor for ≥grade 3 infections (Odds ratio 3·4; 95% CI: 1·4-6·9). CD4+ recovery after BR is unexpectedly delayed and late recovery is associated with risk of serious infections. Monitoring CD4+ following BR could identify patients at high risk of delayed infections.


Asunto(s)
Antineoplásicos Alquilantes/uso terapéutico , Clorhidrato de Bendamustina/uso terapéutico , Trastornos Linfoproliferativos/tratamiento farmacológico , Rituximab/uso terapéutico , Subgrupos de Linfocitos T/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos Alquilantes/farmacología , Clorhidrato de Bendamustina/farmacología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rituximab/farmacología
8.
Am J Kidney Dis ; 72(6): 890-894, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29941220

RESUMEN

Sézary syndrome is a rare aggressive leukemic variant of primary cutaneous T-cell lymphoma, typically presenting with erythroderma, lymphadenopathy, and an atypical clonal T-cell population. Though it often involves the spleen and liver, we report a case of Sézary syndrome with renal involvement that was treated successfully. Visceral involvement confers a poor prognosis requiring systemic treatment. The patient we describe was a 66-year-old man who was referred from Dermatology services for deteriorating kidney function. Polymerase chain reaction of genomic DNA from skin and kidney biopsies confirmed a clonal T-cell population matching a population isolated in peripheral blood. The patient was treated initially with alemtuzumab, which led to a significant improvement in kidney function, and he has subsequently received a successful allogeneic stem cell transplant. This case represents a rare cause of decreased kidney function and highlights the role of biopsy in patients with suspected Sézary syndrome.


Asunto(s)
Alemtuzumab/administración & dosificación , Trasplante de Células Madre Hematopoyéticas/métodos , Neoplasias Renales/secundario , Síndrome de Sézary/patología , Neoplasias Cutáneas/patología , Anciano , Biopsia con Aguja , Terapia Combinada , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Pruebas de Función Renal , Neoplasias Renales/terapia , Masculino , Síndrome de Sézary/terapia , Neoplasias Cutáneas/terapia , Trasplante Homólogo , Resultado del Tratamiento
9.
Blood ; 128(4): 542-52, 2016 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-27118451

RESUMEN

The complex interplay between cancer cells, stromal cells, and immune cells in the tumor microenvironment (TME) regulates tumorigenesis and provides emerging targets for immunotherapies. Crosstalk between CD4(+) T cells and proliferating chronic lymphocytic leukemia (CLL) tumor B cells occurs within lymphoid tissue pseudofollicles, and investigating these interactions is essential to understand both disease pathogenesis and the effects of immunotherapy. Tumor-derived extracellular vesicle (EV) shedding is emerging as an important mode of intercellular communication in the TME. In order to characterize tumor EVs released in response to T-cell-derived TME signals, we performed microRNA (miRNA [miR]) profiling of EVs released from CLL cells stimulated with CD40 and interleukin-4 (IL-4). Our results reveal an enrichment of specific cellular miRNAs including miR-363 within EVs derived from CD40/IL-4-stimulated CLL cells compared with parental cell miRNA content and control EVs from unstimulated CLL cells. We demonstrate that autologous patient CD4(+) T cells internalize CLL-EVs containing miR-363 that targets the immunomodulatory molecule CD69. We further reveal that autologous CD4(+) T cells that are exposed to EVs from CD40/IL-4-stimulated CLL cells exhibit enhanced migration, immunological synapse signaling, and interactions with tumor cells. Knockdown of miR-363 in CLL cells prior to CD40/IL-4 stimulation prevented the ability of CLL-EVs to induce increased synapse signaling and confer altered functional properties to CD4(+) T cells. Taken together, these data reveal a novel role for CLL-EVs in modifying T-cell function that highlights unanticipated complexity of intercellular communication that may have implications for bidirectional CD4(+) T-cell:tumor interactions within the TME.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Antígenos CD40/inmunología , Comunicación Celular/inmunología , Interleucina-4/inmunología , Leucemia Linfocítica Crónica de Células B/inmunología , Proteínas de Neoplasias/inmunología , Vesículas Secretoras/inmunología , Linfocitos T CD4-Positivos/patología , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/patología , Masculino , MicroARNs/inmunología , ARN Neoplásico/inmunología , Vesículas Secretoras/patología , Células Tumorales Cultivadas
10.
Blood ; 127(4): 449-57, 2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26491071

RESUMEN

Antigenic stimulation via the B-cell receptor (BCR) is a major driver of the proliferation and survival of chronic lymphocytic leukemia (CLL) cells. However, the precise mechanisms by which BCR stimulation leads to accumulation of malignant cells remain incompletely understood. Here, we investigated the ability of BCR stimulation to increase messenger RNA (mRNA) translation, which can promote carcinogenesis by effects on both global mRNA translation and upregulated expression of specific oncoproteins. Re-analysis of gene expression profiles revealed striking upregulation of pathways linked to mRNA translation both in CLL cells derived from lymph nodes, the major site of antigen stimulation in vivo, and after BCR stimulation in vitro. Anti-IgM significantly increased mRNA translation in primary CLL cells, measured using bulk metabolic labeling and a novel flow cytometry assay to quantify responses at a single-cell level. These translational responses were suppressed by inhibitors of BTK (ibrutinib) and SYK (tamatinib). Anti-IgM-induced mRNA translation was associated with increased expression of translation initiation factors eIF4A and eIF4GI, and reduced expression of the eIF4A inhibitor, PDCD4. Anti-IgM also increased mRNA translation in normal blood B cells, but without clear modulatory effects on these factors. In addition, anti-IgM increased translation of mRNA-encoding MYC, a major driver of disease progression. mRNA translation is likely to be an important mediator of the growth-promoting effects of antigen stimulation acting, at least in part, via translational induction of MYC. Differences in mechanisms of translational regulation in CLL and normal B cells may provide opportunities for selective therapeutic attack.


Asunto(s)
Regulación Leucémica de la Expresión Génica , Leucemia Linfocítica Crónica de Células B/genética , Proteínas Proto-Oncogénicas c-myc/genética , ARN Mensajero/genética , Receptores de Antígenos de Linfocitos B/inmunología , Adenina/análogos & derivados , Agammaglobulinemia Tirosina Quinasa , Anticuerpos Antiidiotipos/inmunología , Linfocitos B/metabolismo , Linfocitos B/patología , Línea Celular Tumoral , Humanos , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/patología , Piperidinas , Biosíntesis de Proteínas/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Pirazoles/farmacología , Pirimidinas/farmacología , Receptores de Antígenos de Linfocitos B/genética , Quinasa Syk , Células Tumorales Cultivadas
11.
BMC Infect Dis ; 18(1): 58, 2018 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-29374466

RESUMEN

BACKGROUND: We report a fatal case of disseminated adenovirus infection in a non-transplant haematology adult patient with chronic lymphocytic leukaemia who had completed combination chemoimmunotherapy a few months before developing respiratory symptoms. In such non-transplant patients, monitoring for adenovirus in the blood is not routine. However, with adenoviruses, when there is a more peripheral (i.e. non-blood) site of infection such as the chest, serial adenovirus monitoring in blood for the duration of that illness may be warranted. CASE PRESENTATION: This case started with an initial bacterial chest infection that responded to treatment, followed by an adenovirus pneumonitis that disseminated to his blood a week later with levels of up to 92 million adenovirus DNA copies/ml. Despite prompt treatment with cidofovir, his respiratory function continued to deteriorate over the next two weeks and he was moved to intensive care. Intravenous immunoglobulin and ribavirin were subsequently added to his treatment. However, he died soon after this with a final adenovirus load of 20 million copies/ml in his blood. CONCLUSIONS: We recommend that even in non-transplant haematology patients, where such patients present with an acute respiratory adenovirus infection, teams should consider checking the blood for adenovirus to check for signs of disseminated infection. The earlier this can be tested, the earlier treatment can be initiated (if adenovirus positive), which may produce more successful clinical outcomes.


Asunto(s)
Infecciones por Adenovirus Humanos/diagnóstico , Leucemia Linfocítica Crónica de Células B/diagnóstico , Adenoviridae/genética , Adenoviridae/aislamiento & purificación , Infecciones por Adenovirus Humanos/complicaciones , Infecciones por Adenovirus Humanos/virología , Antineoplásicos/uso terapéutico , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/microbiología , Cidofovir , Citosina/análogos & derivados , Citosina/uso terapéutico , ADN Viral/genética , ADN Viral/metabolismo , Quimioterapia Combinada , Resultado Fatal , Haemophilus influenzae/aislamiento & purificación , Humanos , Leucemia Linfocítica Crónica de Células B/complicaciones , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Organofosfonatos/uso terapéutico , Reacción en Cadena de la Polimerasa , Tomografía Computarizada por Rayos X , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico
12.
J Biol Chem ; 291(32): 16686-98, 2016 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-27268052

RESUMEN

We demonstrate the usefulness of synthetic lethal screening of a conditionally BCL6-deficient Burkitt lymphoma cell line, DG75-AB7, with a library of small molecules to determine survival pathways suppressed by BCL6 and suggest mechanism-based treatments for lymphoma. Lestaurtinib, a JAK2 inhibitor and one of the hits from the screen, repressed survival of BCL6-deficient cells in vitro and reduced growth and proliferation of xenografts in vivo BCL6 deficiency in DG75-AB7 induced JAK2 mRNA and protein expression and STAT3 phosphorylation. Surface IL10RA was elevated by BCL6 deficiency, and blockade of IL10RA repressed STAT3 phosphorylation. Therefore, we define an IL10RA/JAK2/STAT3 pathway each component of which is repressed by BCL6. We also show for the first time that JAK2 is a direct BCL6 target gene; BCL6 bound to the JAK2 promoter in vitro and was enriched by ChIP-seq. The place of JAK2 inhibitors in the treatment of diffuse large B-cell lymphoma has not been defined; we suggest that JAK2 inhibitors might be most effective in poor prognosis ABC-DLBCL, which shows higher levels of IL10RA, JAK2, and STAT3 but lower levels of BCL6 than GC-DLBCL and might be usefully combined with novel approaches such as inhibition of IL10RA.


Asunto(s)
Linfoma de Burkitt/tratamiento farmacológico , Carbazoles/farmacología , Subunidad alfa del Receptor de Interleucina-10/metabolismo , Janus Quinasa 2/antagonistas & inhibidores , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-bcl-6/biosíntesis , Factor de Transcripción STAT3/metabolismo , Animales , Linfoma de Burkitt/genética , Linfoma de Burkitt/metabolismo , Línea Celular Tumoral , Furanos , Humanos , Subunidad alfa del Receptor de Interleucina-10/genética , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/metabolismo , Ratones , Ratones SCID , Proteínas Proto-Oncogénicas c-bcl-6/genética , Factor de Transcripción STAT3/genética , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Br J Haematol ; 166(3): 326-35, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24815671

RESUMEN

Follicular helper T-cells (Tfh cells) are a subset of CD4(+) T-cells that are essential for normal production of high affinity antibodies. Tfh cells characteristically produce IL21 and IL4 and show high expression of surface markers CXCR5, ICOS, PDCD1 (PD-1) and the chemokine CXCL13. In this review we will focus on the emerging links between Tfh cells and subtypes of T-cell non-Hodgkin lymphoma: angioimmunoblastic T-cell lymphoma (AITL) and ~20% of peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) have surface marker features of Tfh cells and share a spectrum of genetic abnormalities. The recurrent genetic abnormalities associated with AITL include mutations in epigenetic modifiers such as TET2 and DNMT3A and the motility and adhesion gene, RHOA, is mutated in up to 70% of cases. ~20% of PTCL-NOS demonstrate RHOA mutations and have other characteristics suggesting an origin in Tfh cells. The recognition that specific genetic and surface markers are associated with malignant Tfh cells suggests that the next few years will bring major changes in diagnostic and treatment possibilities. For example, antibodies against IL21, PDCD1 and ICOS are already in clinical trials for autoimmune disease or other malignancies and antibodies against CXCL13 are in pre-clinical development.


Asunto(s)
Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/metabolismo , Humanos , Linfoma de Células B/tratamiento farmacológico , Linfoma de Células B/inmunología , Linfoma de Células B/metabolismo , Linfoma de Células T/tratamiento farmacológico , Linfoma de Células T/inmunología , Linfoma de Células T/metabolismo , Linfocitos T Colaboradores-Inductores/efectos de los fármacos
14.
J Biol Chem ; 287(4): 2608-17, 2012 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-22139839

RESUMEN

Developmental stage-specific regulation of BCL2 occurs during B-cell maturation and has a role in normal immunity. CD40 signaling promotes proliferation and rescues B-cells from apoptosis, partly through induction of BCL2L1 and BCL2A1 and repression of BCL2. We previously showed that a stromal cell/CD40 ligand (CD154) culture system reproduced this switch in survival protein expression in primary human leukemic B-cells and we employed this model system to investigate BCL2 repression. BCL2 was post-transcriptionally regulated and the repressed BCL2 mRNA was associated with non-polysomal, but dense fractions on sucrose density gradients. Microarrays identified a set of miRNA that were induced by culture conditions and potentially able to bind to the BCL2 3'-UTR. Luciferase reporter assays demonstrated that miR-125b and miR-155 repressed BCL2 mRNA but while stromal cell contact alone was sufficient to induce strongly miR-125b this did not cause BCL2 repression. miR-155, which is the most abundant miRNA under basal conditions, specifically required CD154 for further induction above a threshold to exert its full repressive effects. Anti-miR-125b and anti-miR-155 prevented CD154-mediated repression of BCL2 and reduced CD154-mediated proliferation in the MEC1 B-cell line. We suggest that miR-155 and miR-125b, which are induced by CD154 and stromal cell signals, contribute to regulating proliferation and that BCL2 is one of their target mRNAs.


Asunto(s)
Ligando de CD40/metabolismo , Proliferación Celular , Regulación Leucémica de la Expresión Génica , Leucemia Linfocítica Crónica de Células B/metabolismo , MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , ARN Neoplásico/metabolismo , Regiones no Traducidas 3'/genética , Ligando de CD40/genética , Línea Celular Tumoral , Humanos , Leucemia Linfocítica Crónica de Células B/genética , MicroARNs/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , ARN Neoplásico/genética
16.
J Biol Chem ; 287(22): 18308-17, 2012 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-22493480

RESUMEN

The PATZ1 gene encoding a POZ/AT-hook/Kruppel zinc finger (PATZ) transcription factor, is considered a cancer-related gene because of its loss or misexpression in human neoplasias. As for other POZ/domain and Kruppel zinc finger (POK) family members, the transcriptional activity of PATZ is due to the POZ-mediated oligomer formation, suggesting that it might be not a typical transactivator but an architectural transcription factor, thus functioning either as activator or as repressor depending on the presence of proteins able to interact with it. Therefore, to better elucidate PATZ function, we searched for its molecular partners. By yeast two-hybrid screenings, we found a specific interaction between PATZ and BCL6, a human oncogene that plays a key role in germinal center (GC) derived neoplasias. We demonstrate that PATZ and BCL6 interact in germinal center-derived B lymphoma cells, through the POZ domain of PATZ. Moreover, we show that PATZ is able to bind the BCL6 regulatory region, where BCL6 itself acts as a negative regulator, and to contribute to negatively modulate its activity. Consistently, disruption of one or both Patz1 alleles in mice causes focal expansion of thymus B cells, in which BCL6 is up-regulated. This phenotype was almost completely rescued by crossing Patz1(+/-) with Bcl6(+/-) mice, indicating a key role for Bcl6 expression in its development. Finally, a significant number of Patz1 knock-out mice (both heterozygous and homozygous) also develop BCL6-expressing lymphomas. Therefore, the disruption of one or both Patz1 alleles may favor lymphomagenesis by activating the BCL6 pathway.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , Proteínas Represoras/metabolismo , Animales , Secuencia de Bases , Línea Celular , Inmunoprecipitación de Cromatina , Cartilla de ADN , Humanos , Linfoma de Células B/genética , Linfoma de Células B/patología , Ratones , Ratones Noqueados , Unión Proteica , Proteínas Proto-Oncogénicas c-bcl-6 , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
17.
Br J Haematol ; 160(6): 725-33, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23346939

RESUMEN

There is now a plethora of new precision medicines for B-cell malignancy including 'classical' kinase inhibitors, rationally designed inhibitors of anti-apoptotic proteins and antibody or antibody drug/toxin conjugates with functional properties. Some are showing spectacular single agent activity in early phase clinical studies and may reduce or, in combination, even obviate the need for chemotherapy. Nevertheless, significant problems remain if these medicines are to be introduced into routine clinical practice in a rational and affordable manner. Firstly, precision medicines must be carefully matched in a mechanistic fashion with specific subtypes of disease. Whilst sensitivity may be predicted by the detection of key mutations or by expression of target molecules, for therapies that depend on intact intracellular signalling pathways, functional assessment on viable primary malignant cells will be necessary using assays that faithfully mimic in vivo conditions. A second, but no less important challenge is to define mechanism-based synergistic combinations associated with minimal toxicities rather than simply adding new precision medicines to existing chemotherapeutic regimens. Finally, a closer, open, two-way interaction between academic medicine and the pharmaceutical industry will be necessary to achieve these aims. Implementing such changes would change radically how and where patients with B-cell malignancies are managed.


Asunto(s)
Antineoplásicos/farmacología , Leucemia de Células B/tratamiento farmacológico , Linfoma/tratamiento farmacológico , Terapia Molecular Dirigida/métodos , Animales , Antineoplásicos/uso terapéutico , Humanos , Leucemia de Células B/metabolismo , Linfoma/metabolismo
18.
Br J Haematol ; 162(3): 360-70, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23710828

RESUMEN

Chronic lymphocytic leukaemia (CLL) cells encounter T-cells and proliferate in response to T-cell signals in the lymph node microenvironment. In this report we determined interleukin 21 (IL21) function in CLL and showed that IL21 and interleukin 4 (IL4) act co-operatively to promote leukaemic cell proliferation without apoptosis or differentiation We further show that IL21 increased side population (SP) cells, which are associated with resistance to chemotherapy and increased self-renewal capacity in CLL. IL21 and IL4 are the major cytokines produced by the recently described CD4(+) T follicular helper (Tfh) cell subset. Determination of Tfh cells in peripheral blood showed that patients had significantly increased numbers as compared to normal subjects although no association was found between Tfh numbers and IGHV gene mutational status or clinical stage. Our data suggests that the Tfh cytokines, IL4 and IL21, contribute to driving leukaemic cell proliferation in the lymph node microenvironment, and may contribute to the specific production of cells resistant to conventional chemotherapy. We suggest that increased circulating Tfh cells is a component of T-cell dysregulation in CLL. Our findings have implications for the therapeutic use of IL21.


Asunto(s)
Citocinas/inmunología , Leucemia Linfocítica Crónica de Células B/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Apoptosis/inmunología , Ligando de CD40/inmunología , Diferenciación Celular/inmunología , Proliferación Celular , Femenino , Humanos , Interleucina-4/inmunología , Interleucinas/inmunología , Interleucinas/metabolismo , Leucemia Linfocítica Crónica de Células B/patología , Ganglios Linfáticos/inmunología , Recuento de Linfocitos , Masculino , Receptor de Muerte Celular Programada 1/metabolismo , Células Tumorales Cultivadas , Microambiente Tumoral/inmunología
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