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Molecular characterization of Circulating Tumor Cells (CTCs) is still challenging, despite attempts to minimize the drawbacks of Whole Genome Amplification (WGA). In this paper, we propose a Next-Generation Sequencing (NGS) optimized protocol based on molecular tagging technology, in order to detect CTCs mutations while skipping the WGA step. MDA-MB-231 and MCF-7 cell lines, as well as leukocytes, were sorted into pools (2-5 cells) using a DEPArray™ system and were employed to set up the overall NGS procedure. A substantial reduction of reagent volume for the preparation of libraries was performed, in order to fit the limited DNA templates directly derived from cell lysates. Known variants in TP53, KRAS, and PIK3CA genes were detected in almost all the cell line pools (35/37 pools, 94.6%). No additional alterations, other than those which were expected, were found in all tested pools and no mutations were detected in leukocytes. The translational value of the optimized NGS workflow is confirmed by sequencing CTCs pools isolated from eight breast cancer patients and through the successful detection of variants. In conclusion, this study shows that the proposed NGS molecular tagging approach is technically feasible and, compared to traditional NGS approaches, has the advantage of filtering out the artifacts generated during library amplification, allowing for the reliable detection of mutations and, thus, making it highly promising for clinical use.
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Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Análise Mutacional de DNA/métodos , Células Neoplásicas Circulantes/química , Linhagem Celular Tumoral , Classe I de Fosfatidilinositol 3-Quinases/genética , Estudos de Viabilidade , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Células MCF-7 , Medicina de Precisão , Proteínas Proto-Oncogênicas p21(ras)/genética , Análise de Célula Única , Proteína Supressora de Tumor p53/genéticaRESUMO
Differentiated thyroid cancer arising from thyroid follicular epithelial cells is the most frequent endocrine malignancy, and skin metastases are very rare. We describe a case of a 70-year-old women with a history of an indeterminate thyroid nodule on cytology. A painless, erythematous skin nodule of about 7 mm diameter was removed from the scalp and diagnosed as a metastasis from thyroid cancer. After total thyroidectomy, a histological diagnosis of follicular thyroid cancer was made. Two cycles of radioactive iodine were performed. Both the follicular thyroid carcinoma (FTC) and the metastasis were investigated for the presence of BRAF/RAS and TERT promoter mutations. The results showed that the cutaneous metastasis was BRAF wild-type and TERT promoter-mutated (position g.1,295,228 C>T); in contrast, the primary thyroid lesion was negative for both molecular markers.
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BACKGROUND: The demonstration of EGFR T790M gene mutation in plasma is crucial to assess the eligibility of Non Small Cell Lung Cancer (NSCLC) patients, who have acquired resistance to first or second generation Tyrosine Kinase Inhibitors (TKIs), to receive a subsequent treatment with osimertinib. Since circulating tumor DNA (ctDNA) is present in very low amounts in plasma, high sensitive and specific methods are required for molecular analysis. Improving sensitivity of T790M mutation detection in plasma ctDNA enables a larger number of NSCLC patients to receive the appropriate therapy without any further invasive procedure. METHODS: A tag-based next generation sequencing (NGS) platform capable of tagging rare circulating tumor DNA alleles was employed in this study for the identification of T790M mutation in 42 post-TKI NSCLC patients. RESULTS: Compared to Real Time PCR, tag-based NGS improved the T790M detection rate (42.85% versus 21.4%, respectively), especially in those cases with a low median mutation abundance (i.e. 0.24, range 0.07-0.78). Moreover, the tag-based NGS identified EGFR activating mutations more efficiently than Real Time PCR (85.7% versus 61.9% detection rate, respectively), particularly of the L858R variant type (0.06-0.75 mutation abundance range). Patients in whom the T790M mutation was detected in plasma, achieved an objective response to osimertinib (9/14, 64.28%). CONCLUSIONS: Tag-based NGS represents an accurate and sensitive tool in a clinical setting for non-invasive assessment and monitoring of T790M variant in NSCLC patients.
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Carcinoma Pulmonar de Células não Pequenas/genética , DNA Tumoral Circulante/genética , Receptores ErbB/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias Pulmonares/genética , Feminino , Humanos , Masculino , Mutação/genéticaRESUMO
OBJECTIVE: We performed an external and multicentric validation of the predictive value of abdominal computed tomography (aCT) on time to first treatment (TTFT) in early stage chronic lymphocytic leukemia (CLL) patients. METHODS: aCT was performed at diagnosis in 181 Rai 0 patients enrolled in the O-CLL1-GISL trial (clinicaltrial.gov ID:NCT00917549). RESULTS: Fifty-five patients showed an abnormal aCT. Patients with an abnormal aCT showed a significantly shorter TTFT than those with normal aCT (P < 0.0001). At multivariate analysis, aCT (P = 0.011), ß-2 microglobulin (P = 0.019), and CD38 expression (P = 0.047) correlated with TTFT. Following IWCLL 2008 criteria, 112 (61.9%) cases remained at Rai 0, while 69 (38.1%) satisfied the criteria of clinical monoclonal B-cell lymphocytosis (cMBL). Reclassified Rai 0 patients with an abnormal aCT showed a significantly shorter TTFT than those with a normal aCT (P < 0.0001). At multivariate analysis, only aCT (P = 0.011) correlated with TTFT. Eleven cMBL cases (15.9%) showed an abnormal aCT and were reclassified as small lymphocytic lymphomas (SLL); nonetheless, TTFT was similar for cMBLs and SLLs. CONCLUSION: Our results confirm the ability of the abnormal aCT to predict progression in early stage cases.
Assuntos
Leucemia Linfocítica Crônica de Células B/diagnóstico por imagem , Leucemia Linfocítica Crônica de Células B/terapia , Radiografia Abdominal , Tomografia Computadorizada por Raios X , ADP-Ribosil Ciclase 1/sangue , Abdome , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/sangue , Masculino , Pessoa de Meia-Idade , Microglobulina beta-2/sangueRESUMO
Several factors support CLL cell survival in the microenvironment. Under different experimental conditions, IL21 can either induce apoptosis or promote CLL cell survival. To investigate mechanisms involved in the effects of IL21, we studied the ability of IL21 to modulate gene and miRNA expressions in CD40-activated CLL cells. IL21 was a major regulator of chemokine production in CLL cells and it modulated the expression of genes involved in cell movement, metabolism, survival and apoptosis. In particular, IL21 down-regulated the expression of the chemokine genes CCL4, CCL3, CCL3L1, CCL17, and CCL2, while it up-regulated the Th1-related CXCL9 and CXCL10. In addition, IL21 down-regulated the expression of genes encoding signaling molecules, such as CD40, DDR1 and PIK3CD. IL21 modulated a similar set of genes in CLL and normal B-cells (e.g. chemokine genes), whereas other genes, including MYC, TNF, E2F1, EGR2 and GAS-6, were regulated only in CLL cells. An integrated analysis of the miRNome and gene expression indicated that several miRNAs were under IL21 control and these could, in turn, influence the expression of potential target genes. We focused on hsa-miR-663b predicted to down-regulate several relevant genes. Transfection of hsa-miR-663b or its specific antagonist showed that this miRNA regulated CCL17, DDR1, PIK3CD and CD40 gene expression. Our data indicated that IL21 modulates the expression of genes mediating the crosstalk between CLL cells and their microenvironment and miRNAs may take part in this process.
Assuntos
Antígenos CD40/metabolismo , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Interleucinas/farmacologia , Leucemia Linfocítica Crônica de Células B/genética , MicroRNAs/genética , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Quimiocinas/metabolismo , Biologia Computacional , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Leucemia Linfocítica Crônica de Células B/imunologia , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Camundongos , MicroRNAs/metabolismo , Células NIH 3T3 , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de TempoRESUMO
A risk score based on three biological features (CD38, ZAP-70, and IGHV mutational status) was previously developed to predict progression-free survival (PFS) in untreated Binet A CLL patients. Here we perform a score validation analysis in a prospective and independent cohort of patients. Biological markers (CD38, ZAP-70, and IGHV mutational status) and gene expression profiles (GEP) of leukemic cells from CLL patients included in a prospective multicenter observational study (O-CLL1-GISL protocol, clinicaltrial.gov ID:NCT00917549) were used to assess the value and reproducibility of this score. To date, 468 Binet A patients were classified as low- (0 positive marker), intermediate- (1 positive marker), or high-risk (2 or 3 positive markers) using the progression risk score. The 3-year PFS probability was 91.7%, 82.9%, and 57.4% for low-, intermediate-, and high-risk (P < 0.0001) cases, respectively. These values were similar to those found in the original cohort. At Cox multivariate analysis, Rai stage, absolute lymphocyte count, progression risk score, and ß-2 microglobulin maintained an independent prognostic impact on PFS. This score remained a predictor of progression when analysis was limited to 371 Rai 0 cases (P < 0.0001). Finally, the cells from the different CLL risk groups showed differences in their gene expression patterns. These results confirm the ability of this progression risk score to predict PFS among Binet A patients. The utility of the score was also extended by demonstrating that it retains prognostic value when applied exclusively to Rai 0 patients. Specific transcriptional patterns were significantly associated with risk groups.
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Biomarcadores Tumorais/análise , Leucemia Linfocítica Crônica de Células B/diagnóstico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Biomarcadores Tumorais/metabolismo , Estudos de Coortes , Progressão da Doença , Intervalo Livre de Doença , Feminino , Perfilação da Expressão Gênica , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/metabolismo , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Medição de RiscoRESUMO
Reactive oxygen species (ROS) are metabolism by-products that may act as signaling molecules to sustain tumor growth. Antioxidants have been used to impair cancer cell survival. Our goal was to determine the mechanisms involved in the response to antioxidants of a human cell culture (PT4) containing glioblastoma (GBM) tumorigenic initiating cells (TICs). ROS production in the absence or presence of N-acetyl-L-cysteine (NAC), tiron, and trolox was evaluated by flow cytometry (FCM). The effects of these antioxidants on cell survival and apoptosis were evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT) and FCM. The biological processes modulated by these drugs were determined by oligonucleotide microarray gene expression profiling. Our results showed that NAC, tiron and trolox impaired PT4 cell survival, had minor effects on ROS levels and caused wide deregulation of cell cycle genes. Furthermore, tiron and trolox caused inhibition of cell survival in two additional cell cultures containing TICs, FO-1 and MM1, established from a melanoma and a mesothelioma patient, respectively. NAC, instead, impaired survival of the MM1 cells but not of the FO-1 cells. However, when used in combination, NAC enhanced the inhibitory effect of PLX4032 (BRAF V600E inhibitor) and Gefitinib (EGFR inhibitor), on FO-1 and PT4 cell survival. Collectively, NAC, tiron and trolox modulated gene expression and impaired the growth of cultures containing TICs primarily by inhibiting cell cycle progression.
Assuntos
Sal Dissódico do Ácido 1,2-Di-Hidroxibenzeno-3,5 Dissulfônico/farmacologia , Acetilcisteína/farmacologia , Proteínas de Ciclo Celular/genética , Ciclo Celular/efeitos dos fármacos , Cromanos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Perfilação da Expressão Gênica , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Células Tumorais CultivadasRESUMO
Hepatocyte growth factor, produced by stromal and follicular dendritic cells, and present at high concentrations in the sera of patients with chronic lymphocytic leukemia, prolongs the survival of leukemic B cells by interacting with their receptor, c-MET. It is, however, unknown whether hepatocyte growth factor influences microenvironmental cells, such as nurse-like cells, which deliver survival signals to the leukemic clone. We evaluated the expression of c-MET on nurse-like cells and monocytes from patients with chronic lymphocytic leukemia and searched for phenotypic/functional features supposed to be influenced by the hepatocyte growth factor/c-MET interaction. c-MET is expressed at high levels on nurse-like cells and at significantly higher levels than normal on monocytes from patients. Moreover, the hepatocyte growth factor/c-MET interaction activates STAT3(TYR705) phosphorylation in nurse-like cells. Indoleamine 2,3-dioxygenase, an enzyme modulating T-cell proliferation and induced on normal monocytes after hepatocyte growth factor treatment, was detected together with interleukin-10 on nurse-like cells, and on freshly-prepared patients' monocytes. Immunohistochemical/immunostaining analyses demonstrated the presence of c-MET(+) and indoleamine 2,3-dioxygenase(+) cells in lymph node biopsies, co-expressed with CD68 and vimentin. Furthermore nurse-like cells and chronic lymphocytic monocytes significantly inhibited T-cell proliferation, prevented by anti-transforming growth factor beta and interleukin-10 antibodies and indoleamine 2,3-dioxygenase inhibitors, and supported CD4(+)CD25(high+)/FOXP3(+) T regulatory cell expansion. We suggest that nurse-like cells display features of immunosuppressive type 2 macrophages: higher hepatocyte growth factor levels, produced by leukemic or other microenvironmental surrounding cells, may cooperate to induce M2 polarization. Hepatocyte growth factor may thus have a dual pathophysiological role: directly through enhancement of survival of the leukemic clone and indirectly by favoring T-cell immunosuppression.
Assuntos
Indolamina-Pirrol 2,3,-Dioxigenase/genética , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Proteínas Proto-Oncogênicas c-met/genética , Células Cultivadas , Técnicas de Cocultura , Expressão Gênica , Fator de Crescimento de Hepatócito/metabolismo , Fator de Crescimento de Hepatócito/farmacologia , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Interleucina-10/genética , Interleucina-10/metabolismo , Leucemia Linfocítica Crônica de Células B/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Monócitos/patologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/metabolismo , Fator de Transcrição STAT3/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismoRESUMO
INTRODUCTION: Mycosis Fungoides (MF) is a rare malignant T-cell lymphoma, involving mainly the skin. In 50%-75% of cases, it can involve organs other than skin, with a 11%-14% Central Nervous System involvement (CNS). CASE REPORT: A 82-year-old woman presented to our Department with a 15-years history of MF with skin lesions. Neurological examination showed dysarthria and a left facio-brachial-crural hemiparesis. A CT scan showed a right fronto-rolandic lesion. A MRI, including DWI, confirmed the presence of the "neoplastic" lesion with slight hemorrhagic component and leptomeningeal contrast enhancement. Molecular TCR rearrangement test by PCR analysis was performed on skin biopsy, showed the presence of a single peak which fits with a monoclonal TCRG gene rearrangement (size 67). Molecular TCR test was also performed on the cerebrospinal fluid (CSF), which confirmed the presence of lymphocyte clone T g/ more expressed with the same size of that observed in the skin biopsy A total body CT scan did not show any lymphnodal or extranodal disease. The patient died after ten days. CONCLUSION: MF usually occurs in the context of advanced and often histologically transformed cutaneous disease. Isolated CNS involvement is remarkably rare. This case highlights the need for regular neurologic follow-up after the diagnosis of MF, in particular when features that suggest risk of disease progression are present. Furthermore, the analysis of the skin biopsy and above all of CSF by PCR technique, based on our experience, should always be executed in MF patients with signs or symptoms suggesting CNS involvement.
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Total body computed tomography (TB-CT) scan is not mandatory in the diagnostic/staging algorithm of chronic lymphocytic leukemia (CLL). The aim of this study was to determine the value and prognostic significance of TB-CT scan in early stage CLL patients. Baseline TB-CT scan was performed in 240 Binet stage A CLL patients (179 Rai low- and 61 Rai intermediate-risk) included in a prospective multicenter observational study (clinicaltrial.gov ID:NCT00917549). The cohort included 69 clinical monoclonal B lymphocytosis (cMBLs). Patients were restaged considering only radiological data. Following TB-CT scans, 20% of cases reclassified as radiologic Binet (r-Binet) stage B. r-Binet B patients showed a higher incidence of unfavorable cytogenetic abnormalities (P = 0.027), as well as a shorter PFS (P = 0.001). At multivariate analysis, r-Binet stage [HR = 2.48; P = 0.004] and IGHV mutational status [HR = 3.01; P = 0.002] retained an independent predictive value for PFS. Among 179 Rai low-risk cases, 100 were redefined as r-Rai intermediate-risk based upon TB-CT scan data, showing a higher rate of cases with higher ZAP-70 (P = 0.033) and CD38 expression (P = 0.029) and ß2-microglobulin levels (P < 0.0001), as well as a shorter PFS than those with r-Rai low-risk (P = 0.008). r-Rai stage [HR = 2.78; P = 0.046] and IGHV mutational status [HR = 4.25; P = 0.009] retained a significant predictive value for PFS at multivariate analysis. Forty-two percent of cMBL patients were reclassified as r-small lymphocytic lymphomas (r-SLLs) by TB-CT scan. TB-CT scan appears to provide relevant information in early stage CLL related to the potential and the timing of patients to progress towards the more advanced disease stages.
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Leucemia Linfocítica Crônica de Células B/diagnóstico , Linfocitose/diagnóstico , ADP-Ribosil Ciclase 1/genética , Adulto , Idoso , Linfócitos B/metabolismo , Linfócitos B/patologia , Aberrações Cromossômicas , Progressão da Doença , Feminino , Expressão Gênica , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico por imagem , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Linfocitose/diagnóstico por imagem , Linfocitose/genética , Linfocitose/patologia , Masculino , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Estudos Prospectivos , Fatores de Risco , Análise de Sobrevida , Tomografia Computadorizada por Raios X , Proteína-Tirosina Quinase ZAP-70/genética , Microglobulina beta-2/genéticaRESUMO
Metastatic colorectal cancer (mCRC) is frequently characterized by the presence of mutations of the KRAS oncogene, which are generally associated with a poor response to treatment with anti-epidermal growth factor receptor (anti-EGFR) monoclonal antibodies. With the methods currently used, a case is classified as KRAS-mutated when approximately 20% of the cells bear an activating KRAS mutation. These considerations raise the question of whether cells with a mutated KRAS can be found in mCRC cases classified as KRAS wild-type when more sensitive methods are used. In addition, the issue arises of whether these mCRC cases with low proportion of KRAS-mutated cells could account at least in part for the therapeutic failure of anti-EGFR therapies that occur in 40-60% of cases classified as KRAS wild type. In this study, we compared the classical assays with a very sensitive test, a locked nucleic acid (LNA) polymerase chain reaction (PCR), capable of detecting KRAS-mutated alleles at extremely low frequency (detection sensitivity limit 0.25% mutated DNA/wild-type DNA). By analyzing a cohort of 213 mCRC patients for KRAS mutations, we found a 20.6% discordance between the sequencing/TheraScreen methods and the LNA-PCR. Indeed, 44 mCRC patients initially considered KRAS wild type were reclassified as KRAS mutated by using the LNA-PCR test. These patients were more numerous among individuals displaying a clinical failure to anti-EGFR therapies. Failure to respond to these biological treatments occurred even in the absence of mutations in other EGFR pathway components such as BRAF.
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Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Mutação/genética , Oligonucleotídeos , Reação em Cadeia da Polimerase/métodos , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Anticorpos Monoclonais/uso terapêutico , Sequência de Bases , Neoplasias Colorretais/patologia , Análise Mutacional de DNA , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Metástase Neoplásica , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)RESUMO
CONTEXT: The marine diatoms Cocconeis scutellum Ehrenberg (Bacillariophyceae) are known to trigger apoptosis in the androgenic gland of the Mediterranean crustacean Hippolyte inermis Leach (Decapoda), affecting the shrimp's sex reversal. OBJECTIVE: The aim of this study was to evaluate a possible apoptotic effect of extracts and fractions from these microalgae also on human tissues. MATERIALS AND METHODS: The chemical profile of C. scutellum was determined by gas chromatography-mass spectrometry (GC-MS) and, afterwards, organic extracts and fractions from the diatoms were used to treat to breast cancer BT20 cells. Double labeling with annexin V-FITC and isotonic propidium iodide (PI) along with flow cytometry analysis enabled the evaluate of cell apoptosis and viability, whereas hypotonic PI staining was used to analyze the cell cycle in BT20 lines. The involvement of specific caspases was studied by Western blotting. RESULTS: Results demonstrated that the diethyl ether extract and, in particular, fraction 3, the richest fraction in eicosapentaenoic acid (EPA) from the diethyl ether extract, selectively induced apoptosis (up to 89.2% at 1 µg/well of fraction 3) and decreased viability in BT20 cells. The apoptotic effect was displayed in a concentration and time-dependent manner, by activating caspases-8 and 3, and arresting the progression of the cell cycle from S to G2-M phase. EPA alone showed similar apoptotic effects in BT20 cells. DISCUSSION AND CONCLUSION: The study demonstrates the apoptotic activity of C. scutellum diatoms on breast cancer cells and suggests their potential use as a source of apoptotic compounds.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Diatomáceas/química , Ácido Eicosapentaenoico/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Western Blotting , Caspase 3/metabolismo , Caspase 8/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fracionamento Químico , Relação Dose-Resposta a Droga , Ácido Eicosapentaenoico/química , Ácido Eicosapentaenoico/isolamento & purificação , Ativação Enzimática , Feminino , Citometria de Fluxo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Solventes/química , Fatores de TempoRESUMO
OBJECTIVE: Interleukin (IL)-21, a member of the IL-2 family, has antitumor activity and is now being tested in non-Hodgkin's lymphoma in combination with anti-CD20 antibodies. IL-21 may either induce apoptosis or promote growth in different lymphoid malignancies. We therefore investigated the IL-21/IL-21R system in follicular lymphoma (FL) cells. MATERIALS AND METHODS: IL-21R expression was studied by reverse transcription polymerase chain reaction, immunofluorescence, and Western blot analyses. Apoptosis was measured by Annexin-V-propidium iodide staining. Signaling via IL-21R was studied using antibodies specific for phosphorylated Janus-activating kinase and signal transducers and activators of transcription proteins by Western Blot. RESULTS: IL-21R was found on primary FL cells in 15 of 15 cases at diagnosis and IL-21 increased apoptosis in 10 of 10 FL samples. However, cells from areas of diffuse growth in FL and from two diffuse lymphomas evolved from previous FL, showed low IL-21R expression. The latter were also resistant to IL-21-mediated apoptosis. Among lymphoma cell lines bearing the t(14;18) translocation, only 1 of 7 showed increased apoptosis in response to IL-21 stimulation. This cell line was IL-21R-positive, whereas five of six nonresponsive cell lines showed very low IL-21R expression. Intriguingly, one of the IL-21-resistant cell lines (DOHH2) expressed high levels of IL-21R. Treatment with IL-21 or IL-4 upregulated suppressor of cytokine signaling 3 gene expression in the IL-21-responsive cell line, but not in DOHH2 cells, which showed defective Janus-activating kinase/signal transducers and activators of transcription signaling in response to IL-21, in relationship to the lack of Janus-activating kinase 3 gene expression. CONCLUSION: These data indicate that low IL-21R expression or defective signal transduction downstream IL-21R may cause refractoriness to IL-21-mediated effects in some FL cells.
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Apoptose/efeitos dos fármacos , Subunidade alfa de Receptor de Interleucina-21/fisiologia , Interleucinas/fisiologia , Linfoma Folicular/patologia , Linhagem Celular Tumoral/citologia , Linhagem Celular Tumoral/efeitos dos fármacos , Cromossomos Humanos Par 14/ultraestrutura , Cromossomos Humanos Par 18/ultraestrutura , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Subunidade alfa de Receptor de Interleucina-21/biossíntese , Subunidade alfa de Receptor de Interleucina-21/efeitos dos fármacos , Interleucinas/farmacologia , Janus Quinase 3/deficiência , Janus Quinases/fisiologia , Linfoma Folicular/genética , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/fisiologia , Fatores de Transcrição STAT/fisiologia , Transdução de Sinais/efeitos dos fármacos , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/biossíntese , Proteínas Supressoras da Sinalização de Citocina/genética , Translocação GenéticaRESUMO
The importance of post-transcriptional mechanisms for the regulation of the homoeostasis of the immune system and the response to challenge by microorganisms is becoming increasingly appreciated. We investigated the contribution of microRNAs (miRNAs) to macrophage activation induced by lipopolysaccharide (LPS). We first observed that Dicer knockout in bone marrow-derived macrophages (BMDMs) increases the LPS-induced expression of some inflammation mediators. miRNA microarray analysis in BMDMs revealed that LPS significantly induces the expression of a single miRNA, miR-155, and this induction depends on enhanced miR-155 maturation from its precursors. The single-strand RNA-binding protein KH-type splicing regulatory protein (KSRP) binds to the terminal loop of miR-155 precursors and promotes their maturation. Both inhibition of miR-155 and KSRP knockdown enhance the LPS-induced expression of select inflammation mediators, and the effect of KSRP knockdown is reverted by mature miR-155. Our studies unveil the existence of an LPS-dependent post-transcriptional regulation of miR-155 biogenesis. Once induced, miR-155 finely tunes the expression of select inflammation mediators in response to LPS.
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Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , MicroRNAs/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transativadores/metabolismo , Animais , RNA Helicases DEAD-box/deficiência , Endorribonucleases/deficiência , Mediadores da Inflamação/metabolismo , Macrófagos/metabolismo , Camundongos , Processamento Pós-Transcricional do RNA , Ribonuclease III , Ativação TranscricionalRESUMO
Adult T-lymphoblastic lymphoma is rare and has a poor prognosis. In the 80s, following the introduction of sequential, intensified chemotherapy, complete remissions in the order of 75 percent-95 percent of treated patients, were achieved. However, several patients, namely those with advanced disease, continued to relapse either in remission or during maintenance therapy. Moreover, all these early studies were not able to detect any valuable prognostic index to predict the outcome. In an attempt to reduce the relapse rate, upfront autologous stem cell transplantation in patients in complete remission was introduced. The results obtained with this approach were quite homogeneous, indicating a probability of disease-free survival of about 65 percent-75 percent and an overall survival rate of 60 percent. Successive therapies designed since 2000 were able to obtain complete remissions of above 90 percent, with a relapse rate in the order of 30 percent and an overall survival comparable to that obtained with the transplant procedure. Yet, these studies were also unable to detect valuable prognostic factors predictive of the outcome. Moreover, no study on the biologic profile of the disease has been developed. To improve the prognosis of T-lymphoblastic lymphoma it seems necessary to create national registries to collect both clinical and biological data of all lymphoblastic lymphoma patients. In this way it will be possible to reach critical numbers of data with which valid statistical analysis may be performed that is able to detect factors influencing the outcome. Moreover, subsets of patients needing intensified procedures such as stem cell transplant may be detected at diagnosis.
O linfoma linfoblástico de célula T é raro e com prognóstico ruim. Após introdução de terapêutica quimioterápica seqüencial e intensificada, remissões completas passaram a ser obtidas em 75 por cento-95 por cento dos pacientes. Entretanto, muitos pacientes, particularmente aqueles com a chamada doença avançada, continuaram a recair tanto durante a terapia de indução como na manutenção. Além disso, todos estes estudos iniciais não foram capazes de detectar qualquer índice prognóstico capaz de prever a evolução dos pacientes. No sentido de reduzir as taxas de recidiva, o transplante autólogo de célula progenitora hematopoética em pacientes em remissão completa foi introduzido. Os resultados obtidos com esta abordagem foram bastante homogêneos, indicando uma probabilidade de sobrevida livre de doença de 65 por cento-75 por cento e uma sobrevida global de 60 por cento. Sucessivos tratamentos desenhados já nos anos 2000, foram capazes de obter remissões completas acima de 90 por cento, com taxas de recidivas da ordem de 30 por cento e uma sobrevida global comparável à obtida com o transplante. Ainda, estes estudos também não foram capazes de detectar fatores prognósticos relacionados à evolução válidos. Mais ainda, qualquer estudo com perfil biológico foi desenvolvido. Para melhorar o prognóstico do LLB-T parece ser necessário esforço multicêntrico, de caráter nacional ou internacional, para coletar dados clínicos e biológicos. Nesta linha, é possível alcançar número crítico de dados com valor estatístico que poderiam ser capazes de detectar fatores com influência prognóstica. Finalmente, grupos de pacientes necessitam ser identificados para selecionar aqueles que poderiam se beneficiar do transplante de célula progenitora hematopoética detectados ao diagnóstico.
Assuntos
Humanos , Transplante de Medula Óssea , Tratamento Farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras , Transplante AutólogoRESUMO
Noncoding RNA (ncRNA) transcripts are thought to be involved in human tumorigenesis. We report that a large fraction of genomic ultraconserved regions (UCRs) encode a particular set of ncRNAs whose expression is altered in human cancers. Genome-wide profiling revealed that UCRs have distinct signatures in human leukemias and carcinomas. UCRs are frequently located at fragile sites and genomic regions involved in cancers. We identified certain UCRs whose expression may be regulated by microRNAs abnormally expressed in human chronic lymphocytic leukemia, and we proved that the inhibition of an overexpressed UCR induces apoptosis in colon cancer cells. Our findings argue that ncRNAs and interaction between noncoding genes are involved in tumorigenesis to a greater extent than previously thought.
Assuntos
Carcinoma/genética , Leucemia/genética , RNA não Traduzido/química , Sequência de Bases , Análise por Conglomerados , Sequência Conservada , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/fisiologia , Dados de Sequência Molecular , Oncogenes/fisiologia , Análise de Sequência de RNAAssuntos
Leucemia/terapia , Transfusão de Linfócitos/métodos , Transplante de Células-Tronco/métodos , Doença Aguda , Doença Enxerto-Hospedeiro/metabolismo , Humanos , Imunoterapia Adotiva , Neoplasia Residual , Valor Preditivo dos Testes , Recidiva , Indução de Remissão , Risco , Fatores de Tempo , Transplante HomólogoRESUMO
BACKGROUND: The course of chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL) partly depends on the mutational status of the variable region of immunoglobulin heavy chain genes (IgV(H)), which defines two subgroups of tumours: mutated and unmutated. The expression of zeta-associated protein 70 (ZAP70) is significantly associated with the more aggressive unmutated forms. AIMS: To assess the feasibility of the ZAP70 immunohistochemical test on bone-marrow biopsy (BMB) specimens and to compare the results with those of western blotting (WB) and IgV(H) mutational status assessed on neoplastic cells from peripheral blood. METHODS: 26 patients with CLL/SLL detected on BMB and with known IgV(H) mutational status were selected. ZAP70 was determined by immunohistochemistry (IHC) comparing three antibodies from different sources (Upstate, Cell Signaling, Santa Cruz, California, USA) and two different methods (APAAP and EnVision(+)). In 23 cases, ZAP70 WB results were also available. RESULTS: ZAP70 determination on BMB specimens turned out to be easily feasible with routine procedures with reagents from Upstate and Cell Signaling. The results were concordant with those obtained with WB and mutational status analysis in >80% of the cases with both reagents. Three of four discordant cases were mutated/ZAP70 positive, with two staining weakly for ZAP70 on both WB and IHC. CONCLUSIONS: The study confirms the role of ZAP70 as a possible surrogate of mutational status and emphasises its application in routine diagnostics; it discloses a small subset of discordant cases (mutated/ZAP70 weakly positive) that clinically cluster with the more favourable forms.
Assuntos
Biomarcadores Tumorais/metabolismo , Leucemia Linfocítica Crônica de Células B/diagnóstico , Proteína-Tirosina Quinase ZAP-70/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Biópsia , Western Blotting , Medula Óssea/enzimologia , Feminino , Humanos , Técnicas Imunoenzimáticas , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Leucemia Linfocítica Crônica de Células B/enzimologia , Leucemia Linfocítica Crônica de Células B/genética , Masculino , Pessoa de Meia-Idade , Mutação , Proteína-Tirosina Quinase ZAP-70/sangueRESUMO
We analyzed individual VH gene rearrangements in 55 consecutive B-chronic lymphocytic leukemia (B-CLL) patients collected from a northeastern region of Italy, stressing the possible differences related to geographic characteristics of the cohorts studied. Considering the percentage of somatic mutations present in the VH gene sequences and using the 98% cut-off value, 38 of the 55 B-CLL (69%) patients displayed somatic hypermutations and 17 (31%) had a germline configuration. Our results confirm and extend the observations of a bias in the use of certain VH, DH, and JH genes among B-CLL cells. The most frequently used VH genes were VH1-69 (12.7%) with VH3-23 (12.7%) and VH4-34 (10.9%). Collectively these genes accounted for 36.3% of the cases. In the mutated cases, the range of mutations varied from 2% to 15%, with a median of 6.5%. VH1-69 (7 cases, all unmutated) carried few mutations as opposed to VH3-23 (7 cases, 5 of which mutated), VH4-34 (6 cases, all mutated), and VH3-30 (5 cases, all mutated), which show a high load of mutations. D3 family genes were found frequently (38.1%) followed by D2 (27.2%) and D6 (18.1%). The individual D segment most frequently used was D3-3, which was present in 16.3% of cases. There was predominance of the JH4 gene (49%) followed by JH6 (40%). Analysis of the distribution of replacement and silent mutations in the mutated sequences using the method of Lossos showed in 39.4% of cases evidence of antigen selection in the framework region and/or complementary determining regions. In comparison with a recent study on B-CLL patients from the Mediterranean area, the VH4-34 gene was significantly overused in the mutated group at a percentage double that of the Italian cohort reported in this study (10.9% vs. 5%), but at a frequency similar to the entire Mediterranean region (10.7%). We also found an over-representation of VH1-69 usage in the germline group, at a frequency (12.7%) higher than previously described by the same authors (Italian 8%, Mediterranean 10.7%). On the contrary, VH3-07 and VH3-49 were not much used in our study (5.4% and 1.8%, respectively) compared with the Italian group (8% and 5.1%). In our study, VH3-23 gene segment was frequently expressed, at frequency as high as that of VH1-69, a finding in keeping with reported B-CLL Italian data, but higher than the entire series of the Mediterranean area (12.7% vs. 9.2%); VH3-21 gene, frequently expressed in northern European CLL but rarely in the Mediterranean area, was completely absent. This biased usage of VH family genes may reflect a geographic leukemic repertoire, perhaps owing to a peculiar genetic background, depending on variations in germline composition of the IgVH locus or to the effect of a potential environmental element less frequently encountered in different regions.
Assuntos
Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Genes de Cadeia Pesada de Imunoglobulina , Leucemia Linfocítica Crônica de Células B/genética , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/genética , Estudos de Coortes , Regiões Determinantes de Complementaridade/genética , Feminino , Frequência do Gene , Mutação em Linhagem Germinativa , Humanos , Imunoglobulina D/genética , Cadeias J de Imunoglobulina/genética , Itália , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Índice de Gravidade de Doença , Hipermutação Somática de ImunoglobulinaRESUMO
Interleukin-21 (IL-21) is a member of the IL-2 cytokine family, which mediates proliferation or growth arrest and apoptosis of normal B cells, depending on their activation state. Here we demonstrate that surface IL-21 receptor (R) is expressed at variable levels by chronic lymphocytic leukemia (CLL) B cells freshly isolated from 33 different patients. IL-21R expression was up-regulated following cell stimulation via surface CD40. Therefore, IL-21 effects were more evident in CD40-activated CLL B cells. IL-21 induced an early signaling cascade in CLL B cells, which included JAK-1 and JAK-3 autophosphorylation and tyrosine phosphorylation of STAT-1, STAT-3, and STAT-5. IL-21 signaling failed to stimulate CLL B-cell proliferation, but induced their apoptosis. In addition, IL-21 counteracted the proliferative and antiapoptotic signals delivered by IL-15 to CLL B cells. IL-21-mediated apoptosis involved activation of caspase-8 and caspase-3, cleavage of Bid to its active form t-Bid, and cleavage of PARP and of p27Kip-1. Recent data indicate that CLL B cells require interaction with the microenvironment for their survival and expansion. The present findings thus provide a set of new mechanisms involved in the balance between cell-survival and apoptotic signals in CLL B cells.