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1.
Curr Gastroenterol Rep ; 23(7): 9, 2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-33963950

RESUMO

PURPOSE OF THE REVIEW: Primary GI lymphomas of B cell origin are a diverse group of lymphomas. In this article, we provide an overview of the diagnosis, pathologic and molecular features, and management of these varied lymphomas. RECENT FINDINGS: The most common primary GI lymphomas are diffuse large B cell lymphoma (DLBCL) and marginal zone lymphomas (MZL), but follicular lymphomas (FL), mantle cell lymphomas (MCL), post-transplant lymphoproliferative disorders (PTLD), and Burkitt lymphoma of the GI tract also occur. Many features of these lymphomas are similar to their nodal counterparts, but certain clinical and biological aspects are unique. Diagnostic and treatment strategies for these lymphomas continue to evolve over time. There are ongoing discoveries about the unique pathophysiology, molecular characteristics, and complications of primary B cell GI lymphomas that are already leading to improvements in management of this histologically diverse set of lymphomas.


Assuntos
Neoplasias Gastrointestinais , Linfoma de Células B , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/fisiopatologia , Neoplasias Gastrointestinais/terapia , Humanos , Linfoma de Células B/diagnóstico , Linfoma de Células B/genética , Linfoma de Células B/fisiopatologia , Linfoma de Células B/terapia , Linfoma Folicular/diagnóstico , Linfoma Folicular/genética , Linfoma Folicular/fisiopatologia , Linfoma Folicular/terapia , Transtornos Linfoproliferativos/diagnóstico , Transtornos Linfoproliferativos/etiologia , Transtornos Linfoproliferativos/fisiopatologia , Transtornos Linfoproliferativos/terapia
2.
Eur J Ophthalmol ; 31(2): NP91-NP96, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31760781

RESUMO

PURPOSE: To describe the outcome of ultra-low-dose (boom-boom) radiotherapy for choroidal lymphoma. METHODS: Retrospective series of three consecutive patients with biopsy-proven choroidal lymphoma treated with ultra-low-dose radiotherapy. RESULTS: The three patients (two male, one female) of mean age 70 years (range, 64-74 years) demonstrated presenting visual acuity in the affected eye between 20/40 and 20/50. The choroidal lymphoma was unilateral in all cases and presented with multifocal yellow patchy choroidal infiltration, located in all four quadrants and measuring mean 2.9 mm (range, 1.9-4.0 mm) in thickness by ultrasonography. Anterior epibulbar extension of 5 mm diameter was noted in one case. By enhanced depth imaging optical coherence tomography, the choroidal infiltration demonstrated classic undulating appearance (n = 3), with subretinal fluid (n = 2) and intraretinal edema (n = 1). There was no systemic lymphoma in any case. Biopsy was performed in all three cases and was diagnostic (n = 1) or suggestive (n = 2) of B-cell lymphoma. Management involved ultra-low-dose radiotherapy (4 Gy delivered in two fractions, "boom-boom"). On follow-up (mean = 14 months, range = 6-24 months), complete tumor regression on ophthalmoscopy was documented in all three cases, with enhanced depth imaging optical coherence tomography and ultrasonography demonstrating evidence of lymphoma resolution and visual acuity improvement to 20/25-20/40. There were no radiation complications. CONCLUSION: In this small case series, ultra-low-dose (boom-boom) radiotherapy was effective for choroidal lymphoma with favorable response and minimal side effects.


Assuntos
Neoplasias da Coroide/radioterapia , Linfoma de Células B/radioterapia , Idoso , Neoplasias da Coroide/diagnóstico por imagem , Neoplasias da Coroide/fisiopatologia , Feminino , Humanos , Linfoma de Células B/diagnóstico por imagem , Linfoma de Células B/fisiopatologia , Masculino , Pessoa de Meia-Idade , Oftalmoscopia , Dosagem Radioterapêutica , Estudos Retrospectivos , Líquido Sub-Retiniano , Tomografia de Coerência Óptica , Ultrassonografia , Acuidade Visual/fisiologia
3.
Medicina (Kaunas) ; 56(6)2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32570722

RESUMO

Background and Objectives: The injury burden after head trauma is exacerbated by secondary sequelae, which leads to further neuronal loss. B-cell lymphoma 2 (Bcl-2) is an anti-apoptotic protein and a key modulator of the programmed cell death (PCD) pathways. The current study evaluates the clinical evidence on Bcl-2 and neurological recovery in patients after traumatic brain injury (TBI). Materials and Methods: All studies in English were queried from the National Library of Medicine PubMed database using the following search terms: (B-cell lymphoma 2/Bcl-2/Bcl2) AND (brain injury/head injury/head trauma/traumatic brain injury) AND (human/patient/subject). There were 10 investigations conducted on Bcl-2 and apoptosis in TBI patients, of which 5 analyzed the pericontutional brain tissue obtained from surgical decompression, 4 studied Bcl-2 expression as a biomarker in the cerebrospinal fluid (CSF), and 1 was a prospective randomized trial. Results: Immunohistochemistry (IHC) in 94 adults with severe TBI showed upregulation of Bcl-2 in the pericontusional tissue. Bcl-2 was detected in 36-75% of TBI patients, while it was generally absent in the non-TBI controls, with Bcl-2 expression increased 2.9- to 17-fold in TBI patients. Terminal deoxynucleotidyl transferase-mediated biotinylated dUTP nick-end labeling (TUNEL) positivity for cell death was detected in 33-73% of TBI patients. CSF analysis in 113 TBI subjects (90 adults, 23 pediatric patients) showed upregulation of Bcl-2 that peaked on post-injury day 3 and subsequently declined after day 5. Increased Bcl-2 in the peritraumatic tissue, rising CSF Bcl-2 levels, and the variant allele of rs17759659 are associated with improved mortality and better outcomes on the Glasgow Outcome Score (GOS). Conclusions: Bcl-2 is upregulated in the pericontusional brain and CSF in the acute period after TBI. Bcl-2 has a neuroprotective role as a pro-survival protein in experimental models, and increased expression in patients can contribute to improvement in clinical outcomes. Its utility as a biomarker and therapeutic target to block neuronal apoptosis after TBI warrants further evaluation.


Assuntos
Apoptose/fisiologia , Lesões Encefálicas Traumáticas/complicações , Linfoma de Células B/líquido cefalorraquidiano , Biomarcadores/análise , Biomarcadores/líquido cefalorraquidiano , Lesões Encefálicas Traumáticas/líquido cefalorraquidiano , Lesões Encefálicas Traumáticas/fisiopatologia , Humanos , Linfoma de Células B/fisiopatologia , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas c-bcl-2/líquido cefalorraquidiano
4.
Cells ; 9(3)2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-32183335

RESUMO

Apoptosis is a highly conserved mechanism enabling the removal of unwanted cells. Mitochondrial apoptosis is governed by the B-cell lymphoma (BCL-2) family, including anti-apoptotic and pro-apoptotic proteins. Apoptosis evasion by dysregulation of anti-apoptotic BCL-2 members (BCL-2, MCL-1, BCL-XL) is a common hallmark in cancers. To divert this dysregulation into vulnerability, researchers have developed BH3 mimetics, which are small molecules that restore effective apoptosis in neoplastic cells by interfering with anti-apoptotic proteins. Among them, venetoclax is a potent and selective BCL-2 inhibitor, which has demonstrated the strongest clinical activity in mature B-cell malignancies, including chronic lymphoid leukemia, mantle-cell lymphoma, and multiple myeloma. Nevertheless, mechanisms of primary and acquired resistance have been recently described and several features such as cytogenetic abnormalities, BCL-2 family expression, and ex vivo drug testing have to be considered for predicting sensitivity to BH3 mimetics and helping in the identification of patients able to respond. The medical need to overcome resistance to BH3 mimetics supports the evaluation of innovative combination strategies. Novel agents including MCL-1 targeting BH3 mimetics are currently evaluated and may represent new therapeutic options in the field. The present review summarizes the current knowledge regarding venetoclax and other BH3 mimetics for the treatment of mature B-cell malignancies.


Assuntos
Linfócitos B/patologia , Linfoma de Células B/fisiopatologia , Fragmentos de Peptídeos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Apoptose , Linhagem Celular Tumoral , Humanos
5.
Medicine (Baltimore) ; 99(2): e18670, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914056

RESUMO

This retrospective study is to explore the clinicopathologic, immunophenotypic, and molecular genetic features of Waldeyer ring B-cell lymphoma (WR-BCL).Tissue arrays from 65 WR-BCL cases were subjected to pathologic and immunophenotypic detections. Expression of Epstein-Barr virus-encoded small RNA (EBER) was detected by in situ hybridization. Interferon regulatory factor 4 (IRF4), BCL-2, BCL-6, and C-myelocytomatosis viral oncogeneav (MYC) gene abnormalities were investigated using interphase fluorescence in situ hybridization.Among the 65 patients, there were 12 nasopharynx cases, 49 tonsil cases, and 4 tongue root cases. Moreover, there were 49 cases of diffuse large BCL (DLBCL) and 16 cases of follicular lymphoma (FL). More than 60% of the patients had Ann Arbor stage III/IV disease, with infiltrated neighboring organs, invaded spleens, and increased lactate dehydrogenase (LDH) levels. Tumor cells were positive for multiple myeloma antigen 1 (MUM1), BCL-2, BCL-6, and C-MYC. EBER expression was detected in lymphoma cells of 2 cases. Alteration frequencies of IRF4, BCL-2, BCL-6, and C-MYC were 24.6%, 32.3%, 27.7%, and 30.7%, respectively. Approximately 67.69% cases had stages 0 to II disease, while 32.31% cases had stage III disease. Five-year overall survival rate was 65.12%. Eastern Cooperative Oncology Group performance status (ECOG) score ≥2 was the only adverse factor for overall survival. IRF4/MUM1, C-MYC, and CD10 expressions were related to poor disease prognosis. WR-BCLs were largely dependent on ECOG, LDH, and bone marrow involvement. WR-DLBCL was associated with poor survival outcomes compared with WR-FL.The WR-DLBCLs have distinct clinicopathologic features, with correlations between the IRF4/MUM1, C-MYC and CD10 expressions, ECOG, LDH, bone marrow involvement, and the disease prognosis.


Assuntos
Linfoma de Células B/epidemiologia , Linfoma de Células B/fisiopatologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Feminino , Humanos , Hibridização in Situ Fluorescente , Fatores Reguladores de Interferon/biossíntese , Linfoma de Células B/classificação , Linfoma de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-6/biossíntese , Proteínas Proto-Oncogênicas c-myc/biossíntese , Proteínas de Ligação a RNA/biossíntese , Estudos Retrospectivos , Proteínas Ribossômicas/biossíntese , Fatores Sexuais
7.
Balkan Med J ; 36(5): 287-289, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31218878

RESUMO

Background: West Nile virus is an arthropod-borne virus (arbovirus) and emerging cause of significant illness in European and Mediterranean countries. West Nile virus infection can cause severe and potentially fatal neurological illnesses, including encephalitis, meningitis, and acute flaccid paralysis. Additionally, immunosuppression, alcohol abuse, old age, and diabetes mellitus are common factors associated with West Nile neuroinvasive disease. Case Report: In August 2018, a 60-year-old male patient with a history of diffuse large B-cell lymphoma initially presented with symptoms including abdominal pain and distention, nausea, and vomiting. Three days after open abdominal surgery due to adhesive small bowel obstruction, he developed fever, prominent tremors, and rapidly progressing flaccid paralysis. The identification of West Nile virus RNA in the serum sample led to the diagnosis of West Nile neuroinvasive disease. Conclusion: Clinicians should evaluate patients with acute flaccid paralysis for the evidence of West Nile neuroinvasive disease. It is particularly important for healthcare providers to consider West Nile neuroinvasive disease in the differential diagnosis of aseptic meningitis, encephalitis, and acute paralysis cases, especially in endemic areas.


Assuntos
Linfoma Difuso de Grandes Células B/complicações , Febre do Nilo Ocidental/etiologia , Protocolos de Quimioterapia Combinada Antineoplásica , Ciclofosfamida , Doxorrubicina , Humanos , Linfoma de Células B/complicações , Linfoma de Células B/fisiopatologia , Linfoma Difuso de Grandes Células B/fisiopatologia , Masculino , Pessoa de Meia-Idade , Plasmaferese/métodos , Prednisona , Quadriplegia/etiologia , Quadriplegia/fisiopatologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Rituximab , Turquia , Vincristina , Febre do Nilo Ocidental/complicações , Febre do Nilo Ocidental/fisiopatologia , Vírus do Nilo Ocidental/efeitos dos fármacos , Vírus do Nilo Ocidental/patogenicidade
8.
BMJ Case Rep ; 20182018 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-30150351

RESUMO

A 49-year-old woman, known case of diffuse large B-cell lymphoma, presented with complaints of floater in both eyes since 3 days. On examination, visual acuity was 0.18 logMAR in both eyes. Indirect ophthalmoscopy revealed presence of vitreous clumps. Vitreous biopsy was done and the histopathological report suggested a diagnosis of ocular lymphoma. The patient was treated with weekly injections of intravitreal methotrexate in both eyes. The patient developed severe photophobia, watering, redness and diminution of vision in the both eyes 2 days following the fifth dose of intravitreal methotrexate. Severe limbitis with annular corneal epitheliopathy and corneal haze was noted on slit-lamp examination. The patient was started on topical lubricants, antibiotic, ciclosporin, loteprednol, folinic acid and oral folic acid. Complete resolution was noted at 2-week follow-up. The patient, however, refused further injections and was kept on close follow-up to look for recurrence of the disease.


Assuntos
Doenças da Córnea/induzido quimicamente , Epitélio Corneano/efeitos dos fármacos , Lubrificantes Oftálmicos/administração & dosagem , Linfoma de Células B/tratamento farmacológico , Metotrexato/efeitos adversos , Soluções Oftálmicas/administração & dosagem , Doenças da Córnea/tratamento farmacológico , Doenças da Córnea/patologia , Epitélio Corneano/patologia , Feminino , Humanos , Injeções Intravítreas , Linfoma de Células B/complicações , Linfoma de Células B/fisiopatologia , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Resultado do Tratamento , Acuidade Visual , Corpo Vítreo
9.
Ostomy Wound Manage ; 64(4): 44-47, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29718817

RESUMO

Cutaneous diffuse large B-cell lymphoma (DLBCL) usually manifests as papules, nodules, or plaques. A rare case of a patient with a chronic skin ulcer and signs and symptoms of infection, including fever and large amounts of yellow wound exudate, is presented. Fifteen (15) months before diagnosis, a 43-year-old otherwise healthy man noted soreness without apparent cause in his upper chest and a palpable 2 cm x 2 cm focal lump. The patient developed frequent fevers, and the lump enlarged over time, producing purulent exudate. For 14 months, the patient was examined and treated at 5 hospitals, but biopsies, smears, cultures, and various types of nucleic acid testing were negative. Antibiotics to treat the suspected but nonclassified infection were ineffective. Ultimately, debridement and pathological examination of necrotic tissue from the deep sinus revealed DLBCL. The patient was provided chemotherapy, surgical debridement, and negative pressure wound therapy. Wounds started to reduce in size once chemotherapy was initiated. The wound was surgically closed with a split-skin graft, and the patient was discharged 93 days following admission to the authors' facility. This case illustrates the possibility of cutaneous DLBCL in patients with chronic skin ulcers and infectious manifestation that do not respond to antibiotic therapy. Prompt deep tissue debridement and pathological examination of deep tissue will help confirm the presence of cutaneous DLBCL and guide required chemotherapy.


Assuntos
Linfoma de Células B/complicações , Linfoma de Células B/diagnóstico , Úlcera Cutânea/etiologia , Úlcera Cutânea/terapia , Adulto , Desbridamento/métodos , Febre/etiologia , Humanos , Linfoma de Células B/fisiopatologia , Masculino , Tratamento de Ferimentos com Pressão Negativa/métodos , Ferimentos e Lesões/etiologia , Ferimentos e Lesões/fisiopatologia
11.
Intern Med ; 56(7): 827-833, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28381751

RESUMO

We herein report the case of a 52-year-old woman who consulted us because of a 2-month history of a fever, anorexia and weight loss. A physical examination was unremarkable. The blood count showed mild anemia and lymphopenia, and lactate dehydrogenase was elevated. Creatinine clearance was normal and proteinuria was undetectable. CT showed enlarged kidneys. A bone marrow biopsy was normal. PET-CT showed an intense uptake of 18fluorodeoxyglucose in both kidneys. A kidney biopsy provided the diagnosis of intravascular large B-cell lymphoma (IVLBCL). Kidney-limited IVLBCL without an impairment in the renal function or proteinuria has not been described. We analyzed the 38 published cases of IVLBCL involving the kidney to describe the main features of this entity.


Assuntos
Rim/patologia , Linfoma de Células B/diagnóstico , Linfoma de Células B/fisiopatologia , Neoplasias Vasculares/diagnóstico , Neoplasias Vasculares/fisiopatologia , Biópsia , Feminino , Fluordesoxiglucose F18 , Humanos , Linfoma de Células B/diagnóstico por imagem , Pessoa de Meia-Idade , Neoplasias Vasculares/diagnóstico por imagem
12.
Leuk Lymphoma ; 57(7): 1616-24, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27183887

RESUMO

We assessed fertility/gonadal function in premenopausal women treated with dose-adjusted EPOCH-Rituximab for untreated primary mediastinal B-cell lymphoma (PMBL). Eligible patents were ≤ 50 years and premenopausal. Serial reproductive histories were obtained and hormonal assays were performed on serum samples before, at the end of treatment and 4-18 months later. Twenty-eight eligible women had a median age (range) of 31 (21-50) years and were followed a median of 7.3 years. Of 23 patients who completed a questionnaire, 19 (83%) were and four were not menstruating prior to chemotherapy. Amenorrhea developed in 12 patients during chemotherapy. At > 1-year follow-up, 14/19 (74%) patients were menstruating, all < 35 years old, and six (43%) of these patients delivered healthy children. Hormonal assays showed ovarian dysfunction during chemotherapy in all patients with varying recovery at 4-18 months after treatment. Fertility was preserved in most women with ovarian failure confined to patients > 40 years old.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Fertilidade/efeitos dos fármacos , Linfoma de Células B/fisiopatologia , Neoplasias do Mediastino/fisiopatologia , Adulto , Anticorpos Monoclonais Murinos/efeitos adversos , Anticorpos Monoclonais Murinos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores , Ciclofosfamida/efeitos adversos , Ciclofosfamida/uso terapêutico , Doxorrubicina/efeitos adversos , Doxorrubicina/uso terapêutico , Etoposídeo/efeitos adversos , Etoposídeo/uso terapêutico , Feminino , Seguimentos , Hormônios Esteroides Gonadais/sangue , Humanos , Linfoma de Células B/diagnóstico , Linfoma de Células B/tratamento farmacológico , Neoplasias do Mediastino/diagnóstico , Neoplasias do Mediastino/tratamento farmacológico , Menstruação/efeitos dos fármacos , Pessoa de Meia-Idade , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Gravidez , Resultado da Gravidez , Rituximab/administração & dosagem , Vincristina/efeitos adversos , Vincristina/uso terapêutico , Adulto Jovem
13.
Appl Immunohistochem Mol Morphol ; 24(7): 482-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26200839

RESUMO

P27 is an important cell cycle regulatory protein. Many reports have validated the utility of p27 as a prognostic marker in different human cancers and to prove its prognostic role in B-cell neoplasm; 80 newly diagnosed B-cell neoplasm patients with mean age of 46.6 years recruited from Hematology/Oncology Unit of Ain Shams University Hospitals during the period from January 2008 till June 2010 were studied for their p27 immunostaining results which showed that all cases of chronic lymphocytic leukemia (CLL) were positive for p27, whereas all mantly cell lymphoma cases were negative for it. There was significantly higher p27 positivity in CLL cases compared with non-Hodgkin lymphoma and that indolent cases showed significantly higher rate of positivity when compared with aggressive and highly aggressive cases. So, we can use this marker to differentiate CLL and mantly cell lymphoma in cases of confusion.


Assuntos
Linfócitos B/patologia , Linfoma de Células B/fisiopatologia , Antígeno Nuclear de Célula em Proliferação/metabolismo , Erros de Diagnóstico , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Coloração e Rotulagem
14.
J Drug Target ; 24(1): 47-57, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26204323

RESUMO

BACKGROUND: Rituximab is widely used in clinical setting for the treatment of B malignant lymphoma and has achieved remarkable success. However, in most patients, the disease ultimately relapses and become resistant to rituximab. To overcome the limitation, there is still a need to find novel strategy for improving therapeutic efficacy. OBJECTIVE: To construct genetically engineered antibody anti-CD19(Fab)-LDM, and verify the anticancer activity targeted toward B-lymphoma. METHODS: The anticancer activity of anti-CD19(Fab)-LDM in vitro and in vivo was examined. In vitro, the binding activity and internalization of anti-CD19(Fab)-LDP were measured. Using comet assay and apoptosis, the cytotoxicity of energized fusion proteins was observed. From in vivo experiments, targeting of therapeutic effect and anticancer efficacy bythe fusion protein was verified. RESULTS: Data showed that anti-CD19(Fab)-LDM does not only binding the cell surface but is also internalized into the cell. The energized fusion proteins anti-CD19(Fab)-LDM can induce DNA damage. Furthermore, significant in vivo therapeutic efficacy was observed. CONCLUSION: The present study demonstrated that the genetically engineered antibody anti-CD19(Fab)-LDM exhibited enhanced cytotoxicity compared to LDM alone. One of the most powerful advantages of anti-CD19(Fab)-LDM, however, is that it can be internalized within the cells and carry out cytotoxic effects. Therefore, anti-CD19(Fab)-LDM may be as a useful targeted therapy for B-cell lymphoma.


Assuntos
Aminoglicosídeos/farmacologia , Antibióticos Antineoplásicos/farmacologia , Anticorpos Monoclonais/farmacologia , Antígenos CD19/imunologia , Enedi-Inos/farmacologia , Linfoma de Células B/fisiopatologia , Proteínas Recombinantes de Fusão/farmacologia , Aminoglicosídeos/administração & dosagem , Animais , Antibióticos Antineoplásicos/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/química , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Relação Dose-Resposta a Droga , Portadores de Fármacos , Enedi-Inos/administração & dosagem , Feminino , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Recombinantes de Fusão/administração & dosagem
16.
Curr Biol ; 25(5): R198-201, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25734269

RESUMO

Apoptosis is an essential form of cell death underlying daily tissue regeneration. In tumor biology, apoptosis resistance is a well-established hallmark of cancer that is targeted by therapeutic approaches. A new study assigns a hitherto-underestimated function to this 'deadly friend': apoptotic cells promote tumor growth, accumulation of tumor-associated macrophages, and angiogenesis.


Assuntos
Apoptose/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Linfoma de Células B/fisiopatologia , Fagócitos/fisiologia , Transdução de Sinais/fisiologia , Microambiente Tumoral/fisiologia , Humanos
17.
Curr Biol ; 25(5): 577-88, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25702581

RESUMO

BACKGROUND: Cells undergoing apoptosis are known to modulate their tissue microenvironments. By acting on phagocytes, notably macrophages, apoptotic cells inhibit immunological and inflammatory responses and promote trophic signaling pathways. Paradoxically, because of their potential to cause death of tumor cells and thereby militate against malignant disease progression, both apoptosis and tumor-associated macrophages (TAMs) are often associated with poor prognosis in cancer. We hypothesized that, in progression of malignant disease, constitutive loss of a fraction of the tumor cell population through apoptosis could yield tumor-promoting effects. RESULTS: Here, we demonstrate that apoptotic tumor cells promote coordinated tumor growth, angiogenesis, and accumulation of TAMs in aggressive B cell lymphomas. Through unbiased "in situ transcriptomics" analysis-gene expression profiling of laser-captured TAMs to establish their activation signature in situ-we show that these cells are activated to signal via multiple tumor-promoting reparatory, trophic, angiogenic, tissue remodeling, and anti-inflammatory pathways. Our results also suggest that apoptotic lymphoma cells help drive this signature. Furthermore, we demonstrate that, upon induction of apoptosis, lymphoma cells not only activate expression of the tumor-promoting matrix metalloproteinases MMP2 and MMP12 in macrophages but also express and process these MMPs directly. Finally, using a model of malignant melanoma, we show that the oncogenic potential of apoptotic tumor cells extends beyond lymphoma. CONCLUSIONS: In addition to its profound tumor-suppressive role, apoptosis can potentiate cancer progression. These results have important implications for understanding the fundamental biology of cell death, its roles in malignant disease, and the broader consequences of apoptosis-inducing anti-cancer therapy.


Assuntos
Apoptose/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Linfoma de Células B/fisiopatologia , Fagócitos/fisiologia , Transdução de Sinais/fisiologia , Microambiente Tumoral/fisiologia , Análise de Variância , Proliferação de Células/fisiologia , Fluorescência , Perfilação da Expressão Gênica , Técnicas Histológicas , Humanos , Estimativa de Kaplan-Meier , Macrófagos/fisiologia , Metaloproteinases da Matriz/metabolismo , Melanoma Experimental/fisiopatologia , Neovascularização Patológica/fisiopatologia
19.
Nat Commun ; 5: 5057, 2014 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-25266931

RESUMO

The capacity of dendritic cells (DCs) to regulate tumour-specific adaptive immune responses depends on their proper differentiation and homing status. Whereas DC-associated tumour-promoting functions are linked to T-cell tolerance and formation of an inflammatory milieu, DC-mediated direct effects on tumour growth have remained unexplored. Here we show that deletion of DCs substantially delays progression of Myc-driven lymphomas. Lymphoma-exposed DCs upregulate immunomodulatory cytokines, growth factors and the CCAAT/enhancer-binding protein ß (C/EBPß). Moreover, Eµ-Myc lymphomas induce the preferential translation of the LAP/LAP* isoforms of C/EBPß. C/EBPß(-/-) DCs are unresponsive to lymphoma-associated cytokine changes and in contrast to wild-type DCs, they are unable to mediate enhanced Eµ-Myc lymphoma cell survival. Antigen-specific T-cell proliferation in lymphoma-bearing mice is impaired; however, this immune suppression is reverted by the DC-restricted deletion of C/EBPß. Thus, we show that C/EBPß-controlled DC functions are critical steps for the creation of a lymphoma growth-promoting and -immunosuppressive niche.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/imunologia , Células Dendríticas/imunologia , Linfoma de Células B/imunologia , Proteína Oncogênica p55(v-myc)/imunologia , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Diferenciação Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Células Dendríticas/citologia , Humanos , Linfoma de Células B/genética , Linfoma de Células B/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína Oncogênica p55(v-myc)/genética
20.
J Hematol Oncol ; 7: 57, 2014 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-25112836

RESUMO

Toll-like receptors (TLRs) are important players in B-cell activation, maturation and memory and may be involved in the pathogenesis of B-cell lymphomas. Accumulating studies show differential expression in this heterogeneous group of cancers. Stimulation with TLR specific ligands, or agonists of their ligands, leads to aberrant responses in the malignant B-cells. According to current data, TLRs can be implicated in malignant transformation, tumor progression and immune evasion processes. Most of the studies focused on multiple myeloma and chronic lymphocytic leukemia, but in the last decade the putative role of TLRs in other types of B-cell lymphomas has gained much interest. The aim of this review is to discuss recent findings on the role of TLRs in normal B cell functioning and their role in the pathogenesis of B-cell malignancies.


Assuntos
Linfócitos B/metabolismo , Transformação Celular Neoplásica/metabolismo , Linfoma de Células B/fisiopatologia , Receptores Toll-Like/metabolismo , Evasão Tumoral/fisiologia , Progressão da Doença , Humanos
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