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The efficacy and safety of thrombopoietin receptor agonists (TRAs) in older patients with primary immune thrombocytopenia (ITP) are unknown. We investigated TRA response and switch, thrombotic/hemorrhagic risk, and sustained responses off-treatment (SROTs) in 384 patients with ITP aged ≥60 years. After 3 months, 82.5% and 74.3% of eltrombopag- and romiplostim-treated patients, respectively, achieved a response; 66.7% maintained the response (median follow-up, 2.7 years). Eighty-five (22.2%) patients switched to the alternative TRA; although no cross-toxicity was observed, 83.3% of resistant patients had a response after the switch. Thirty-four major thromboses (3 fatal) and 14 major hemorrhages (none fatal) occurred in 18 and 10 patients, respectively, while on TRAs and were associated with thrombosis history (subdistribution hazard ratio, 2.04, P = .05) and platelet count <20 × 109/L (subdistribution hazard ratio, 1.69; P = .04), respectively, at TRA start. A recurrent event occurred in 15.6% of patients surviving thrombosis, in all cases but 1 during persisting TRA treatment (incidence rate, 7.7 per 100 patient-years). All recurrences occurred in the absence of adequate antithrombotic secondary prophylaxis. Sixty-two (16.5%) responding patients discontinued TRAs; 53 (13.8%) patients maintained SROTs, which were associated with TRA discontinuation in complete response (P < .001). Very old age (≥75 years; 41.1%) was associated with the more frequent start of TRAs in the persistent/acute phase but not with response or thrombotic/hemorrhagic risk. TRAs are effective in older patients with ITP, with no fatal hemorrhages and with SROTs in a significant portion of patients. Caution is warranted in patients with a history of thrombosis, and a careful risk/benefit balance should be considered.
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Benzoatos , Hidrazinas , Púrpura Trombocitopênica Idiopática , Pirazóis , Receptores Fc , Receptores de Trombopoetina/antagonistas & inibidores , Proteínas Recombinantes de Fusão , Trombopoetina , Trombose , Idoso , Idoso de 80 Anos ou mais , Benzoatos/administração & dosagem , Benzoatos/efeitos adversos , Feminino , Seguimentos , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Humanos , Hidrazinas/administração & dosagem , Hidrazinas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Púrpura Trombocitopênica Idiopática/mortalidade , Pirazóis/administração & dosagem , Pirazóis/efeitos adversos , Receptores Fc/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/efeitos adversos , Estudos Retrospectivos , Trombopoetina/administração & dosagem , Trombopoetina/efeitos adversos , Trombose/induzido quimicamente , Trombose/mortalidadeRESUMO
Clinical or biological parameters useful to predict progression during treatment in real-life setting with ibrutinib, idelalisib and venetoclax in relapsed/refractory chronic lymphocytic leukemia (CLL) are still debated. We conducted a multi-center retrospective study on CLL patients treated with ibrutinib and/or idelalisib who were switched to venetoclax for progression or due to adverse events to identify any clinical and/or biological parameters useful to predict progression during treatment with venetoclax. Of all the 128 evaluable patients, 81 had received ibrutinib prior to switching to venetoclax, 35 had received idelalisib and 12 both. When comparing the three subgroups, we did not notice any statistical difference in terms of clinical or biological features. No variable at baseline and at different time points during the follow-up (at 6, 12, 18 and 24 months) was found to predict progression nor to have significance for Progression Free Survival (PFS) in the ibrutinib group and in the idelalisib group and in subgroups according to the line of treatment. Analyzing the data of the venetoclax treatment, after a median follow up of 14.3 months, median PFS was not reached and estimated 3-year PFS was 54%. Of the 128 patients treated with venetoclax, 28 (22%) experienced progressive disease. At multivariate analysis for predictive factors for progression, lymph node diameter >56.5 mm before starting treatment emerged as an independent risk factor for progression. The lymph node predictive role for progression during venetoclax treatment could be a new parameter that deserves to be investigate in future studies.
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Leucemia Linfocítica Crônica de Células B , Linfadenopatia , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Estudos Retrospectivos , Linfadenopatia/induzido quimicamente , Linfadenopatia/tratamento farmacológico , Compostos Bicíclicos Heterocíclicos com Pontes/efeitos adversos , Recidiva , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversosRESUMO
Chronic lymphocytic leukaemia (CLL) is characterised by the expansion of a neoplastic mature B cell clone. CLL clinical outcome is very heterogeneous, with some subjects never requiring therapy and some showing an aggressive disease. Genetic and epigenetic alterations and pro-inflammatory microenvironment influence CLL progression and prognosis. The involvement of immune-mediated mechanisms in CLL control needs to be investigated. We analyse the activation profile of innate and adaptive cytotoxic immune effectors in a cohort of 26 CLL patients with stable disease, as key elements for immune-mediated control of cancer progression. We observed an increase in CD54 expression and interferon (IFN)-γ production by cytotoxic T cells (CTL). CTL ability to recognise tumour-targets depends on human leukocyte antigens (HLA)-class I expression. We observed a decreased expression of HLA-A and HLA-BC on B cells of CLL subjects, associated with a significant reduction in intracellular calnexin that is relevant for HLA surface expression. Natural killer (NK) cells and CTL from CLL subjects show an increased expression of the activating receptor KIR2DS2 and a reduction of 3DL1 and NKG2A inhibiting molecules. Therefore, an activation profile characterises CTL and NK cells of CLL subjects with stable disease. This profile is conceivable with the functional involvement of cytotoxic effectors in CLL control.
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Antineoplásicos , Leucemia Linfocítica Crônica de Células B , Humanos , Linfócitos T Citotóxicos , Células Matadoras Naturais , Linfócitos B , Antígenos de Histocompatibilidade Classe I , Microambiente TumoralRESUMO
Chronic lymphocytic leukaemia (CLL) is associated with apoptosis resistance and defective control of cell growth. Our study describes for the first time a critical role in CLL for the KRAB-zinc finger protein ZNF224. High ZNF224 transcript levels were detected in CLL patients with respect to control cells. Moreover, ZNF224 expression was significantly lowered after conventional chemotherapy treatment in a subset of CLL patients. By in vitro experiments we confirmed that ZNF224 expression is suppressed by fludarabine and demonstrated that ZNF224 is involved in apoptosis resistance in CLL cells. Moreover, we showed that ZNF224 positively modulates cyclin D3 gene expression. Consistently, we observed that alteration of ZNF224 expression leads to defects in cell cycle control. All together, our results strongly suggest that in CLL cells high expression level of ZNF224 can lead to inappropriate cell growth and apoptosis resistance, thus contributing to CLL progression. Targeting ZNF224 could thus improve CLL response to therapy.
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Ciclina D3/genética , Resistencia a Medicamentos Antineoplásicos/genética , Leucemia Linfocítica Crônica de Células B/genética , Proteínas Repressoras/genética , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Ciclina D3/biossíntese , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Proteínas Repressoras/biossíntese , Vidarabina/administração & dosagem , Vidarabina/análogos & derivadosAssuntos
COVID-19 , Fator V/antagonistas & inibidores , Adulto , COVID-19/complicações , Feminino , HumanosRESUMO
BACKGROUND: Two noninferiority, randomized, controlled trials were conducted in parallel comparing the safety and efficacy of platelets treated with Intercept or Mirasol pathogen-reduction technologies versus standard platelets. STUDY DESIGN AND METHODS: The primary endpoint was the percentage of hematology patients who developed World Health Organization Grade 2 or greater bleeding. A noninferiority margin of 11% was chosen based on expected Grade 2 or greater bleeding in 20% of controls. The study was closed for financial restrictions before reaching the planned sample size of 828 patients, and an intention-to-treat analysis was conducted on 424 evaluable patients. RESULTS: In the Intercept trial (113 treated vs. 115 control patients), the absolute risk difference in Grade 2 or greater bleeding was 6.1%, with an upper one-sided 97.5% confidence limit of 19.2%. The absolute risk difference in the Mirasol trial (99 treated vs. 97 control patients) was 4.1%, and the upper one-sided 97.5% confidence limit was 18.4%. Neither absolute risk difference was statistically significant. In both trials, posttransfusion platelet count increments were significantly lower in treated versus control patients. Mean blood component use in treated patients versus controls was 54% higher (95% confidence interval, 36%-74%; Intercept) and 34% higher (95% confidence interval, 16%-54%; Mirasol) for platelets and 23% higher (95% confidence interval, 8%-39%; Intercept) and 32% higher (95% confidence interval, 10%-57%; Mirasol) for red blood cells. Unexpected reactions and adverse events were not reported. Mortality did not differ significantly between treated and control patients. CONCLUSION: Although conclusions on noninferiority could not be drawn due to low statistical power, the study provides additional information on the safety and efficacy of pathogen-reduced platelets treated with two commercial pathogen-reduction technologies.
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Antissepsia/métodos , Hemorragia/etiologia , Transfusão de Plaquetas/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antissepsia/normas , Preservação de Sangue/métodos , Transmissão de Doença Infecciosa/prevenção & controle , Feminino , Hemorragia/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Transfusão de Plaquetas/métodos , Adulto JovemAssuntos
COVID-19/complicações , Leucemia Linfocítica Crônica de Células B/terapia , SARS-CoV-2/imunologia , Vacinação/métodos , Idoso , COVID-19/prevenção & controle , COVID-19/transmissão , COVID-19/virologia , Gerenciamento Clínico , Feminino , Humanos , Itália/epidemiologia , Leucemia Linfocítica Crônica de Células B/epidemiologia , Leucemia Linfocítica Crônica de Células B/virologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de TempoAssuntos
Anemia Hemolítica Autoimune/diagnóstico , Anemia Hemolítica Autoimune/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Hemolítica Autoimune/economia , Criança , Pré-Escolar , Atenção à Saúde/economia , Feminino , Recursos em Saúde/economia , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Adulto JovemRESUMO
About 10% of the human immunodeficiency virus (HIV) patients show thrombocytopenia. We describe the case of an HIV/HCV-positive patient whose autoimmune thrombocytopenia resolved with the addition of raltegravir to previous highly active antiretroviral therapy (HAART). It is noteworthy that the effect on platelet count appeared to be independent of viral load suppression, which was achieved with previous antiretroviral regimens. In fact, it has been suggested that the positive effect exerted by raltegravir on autoimmune diseases is due to its inhibition on herpes viruses, and hence on activation of endogenous human retroviruses. This consideration, if confirmed, could open new avenues in the treatment of autoimmune thrombocytopenia in the HIV setting.
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Fármacos Anti-HIV/efeitos adversos , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Púrpura Trombocitopênica Idiopática/induzido quimicamente , Púrpura Trombocitopênica Idiopática/virologia , Pirrolidinonas/efeitos adversos , Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/virologia , Humanos , Masculino , Pirrolidinonas/administração & dosagem , Raltegravir PotássicoRESUMO
Chronic lymphocytic leukemia (CLL) is a heterogeneous disease, whose presentation and clinical course are highly variable. Identification of novel prognostic factors may contribute to improving the CLL classification and providing indications for treatment options. The zinc finger protein ZNF224 plays a key role in cell transformation, through the control of apoptotic and survival pathways. In this study, we evaluated the potential application of ZNF224 as a novel marker of CLL progression and therapy responsiveness. To this aim, we analyzed ZNF224 expression levels in B lymphocytes from CLL patients at different stages of the disease and in patients showing different treatment outcomes. The expression of ZNF224 was significantly increased in disease progression and dramatically decreased in patients in complete remission after chemotherapy. Gene expression correlation analysis performed on datasets of CLL patients revealed that ZNF224 expression was well correlated with that of some prognostic and predictive markers. Moreover, bioinformatic analysis coupled ZNF224 to NF-κB pathway, and experimental data demonstrated that RNA interference of ZNF224 reduced the activity of the NF-κB survival pathway in CLL cells. Consistently with a pro-survival role, ZNF224 knockdown raised spontaneous and drug-induced apoptosis and inhibited the proliferation of peripheral blood mononuclear cells from CLL patients. Our findings provide evidence for the involvement of ZNF224 in the survival of CLL cells via NF-κB pathway modulation, and also suggest ZNF224 as a prognostic and predictive molecular marker of CLL disease.
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Chronic Lymphocytic Leukemia (CLL) is a heterogeneous disease characterized by variable clinical courses among different patients. This notion was supported by the possible coexistence of two or more independent CLL clones within the same patients, identified by the characterization of the B cell receptor immunoglobulin (BcR IG) idiotypic sequence. By using the antigen-binding site of the BcR IG as bait, the identification and isolation of aggressive and drug-resistance leukemic B-cell clones could allow a deeper biological and molecular investigation. Indeed, by the screening of phage display libraries, we previously selected a peptide binder of the idiotypic region of CLL BCR IGs expressing the unmutated rearrangement IGHV1-69 and used it as a probe to perform a peptide-based cell sorting by flow cytometry in peripheral blood samples from patients with CLL. Since the IGHV1-69 clones persisted during the follow-up time in both patients, we explored the possibility of these clones having acquired an evolutive advantage compared to the other coexisting clones in terms of a higher expression of genes involved in the survival and apoptosis escape processes. To this end, we studied the expression patterns of a panel of genes involved in apoptosis regulation and in NF-kB-dependent pro-survival signals by comparative qRT-PCR assays. According to the results, IGHV1-69 clones showed a higher expression of pro-survival and anti-apoptotic genes as compared to the other CLL clones with different immunogenetic characteristics. Moreover, these IGHV1-69 clones did not carry any characteristic genetic lesions, indicating the relevance of our approach in performing a comprehensive molecular characterization of single tumor clones, as well as for designing new personalized therapeutic approaches for the most aggressive and persistent tumor clones.
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We herein report an innovative antisense approach based on Peptide Nucleic Acids (PNAs) to down-modulate CD5 expression levels in chronic lymphocytic leukemia (CLL). Using bioinformatics tools, we selected a 12-mer tract of the CD5 mRNA as the molecular target and synthesized the complementary and control PNA strands bearing a serine phosphate dipeptide tail to enhance their water solubility and bioavailability. The specific recognition of the 12-mer DNA strand, corresponding to the target mRNA sequence by the complementary PNA strand, was confirmed by non-denaturing polyacrylamide gel electrophoresis, thermal difference spectroscopy, circular dichroism (CD), and CD melting studies. Cytofluorimetric assays and real-time PCR analysis demonstrated the downregulation of CD5 expression due to incubation with the anti-CD5 PNA at RNA and protein levels in Jurkat cell line and peripheral blood mononuclear cells from B-CLL patients. Interestingly, we also observed that transfection with the anti-CD5 PNA increases apoptotic response induced by fludarabine in B-CLL cells. The herein reported results suggest that PNAs could represent a potential candidate for the development of antisense therapeutic agents in CLL.
Assuntos
Leucemia Linfocítica Crônica de Células B , Ácidos Nucleicos Peptídicos , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/genética , Leucócitos Mononucleares , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/farmacologia , Ácidos Nucleicos Peptídicos/química , RNA Mensageiro/genéticaRESUMO
The current COVID-19 pandemic requires revisiting our current approach to major blood disorders, including ITP (Immune Thrombocytopenia), stirring up the production of several disease-specific practical guidelines. This report describes an updated version of consensus-based practical guidelines on the management of ITP, adapted to the Italian health system and social context. It highlights the role of the hematologist in offering guidance for choosing differentiated approaches in relation to specific circumstances and is intended to provide them with a useful tool for sharing the decision-making process with their patients. Probably, the greatest risk to avoid for a patient with suspected, ongoing or relapsed ITP - that is not severe enough to place him or her at risk for major bleeding - is to be infected in non-hospital and hospital healthcare settings. This risk must be carefully considered when adapting the diagnostic and therapeutic approach. More in detail, the document first addresses the appropriate management for COVID-19 negative patients with newly diagnosed ITP or who experience a relapse of previous ITP, according to first and second lines of treatment and then the management of COVID-19 positive patients according to their severity, from paucisymptomatic to those requiring admission to Intensive Cure Units (ICU). The pros and cons of the different treatments required to correct platelet count are discussed, as are some specific situations, including chronic ITP, splenectomy, thromboembolic complication and anti COVID-19 vaccination.
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The immunoglobulin B cell receptor (IgBCR) expressed by chronic lymphocytic leukemia (CLL) B cells plays a pivotal role in tumorigenesis, supporting neoplastic transformation, survival, and expansion of tumor clones. We demonstrated that in the same patient, two or more CLL clones could coexist, recognized by the expression of different variable regions of the heavy chain of IgBCR, composing the antigen-binding site. In this regard, phage display screening could be considered the easier and most advantageous methodology for the identification of small peptide molecules able to mimic the natural antigen of the tumor IgBCRs. These molecules, properly functionalized, could be used as a probe to specifically identify and isolate single CLL subpopulations, for a deeper analysis in terms of drug resistance, phenotype, and gene expression. Furthermore, CLL cells express another surface membrane receptor, the CD5, which is commonly expressed by normal T cells. Piece of evidence supports a possible contribution of CD5 to the selection and maintenance of autoreactivity in B cells and the constitutive expression of CD5 on CLL cells could induce pro-survival stimuli. In this brief research report, we describe a peptide-based single-cell sorting using as bait the IgBCR of tumor cells; in the next step, we performed a quantitative analysis of CD5 expression by qRT-PCR related to the expressed IgBCR. Our approach could open a new perspective for the identification, isolation, and investigation of all subsets of IgBCR-related CLL clones, with particular attention to the more aggressive clones.
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INTRODUCTION: In patients with primary immune thrombocytopenia (ITP), a short course of steroids is routinely given as first-line therapy. However, the response is often transient and additional therapy is usually needed. Thrombopoietin receptor agonists (TPO-RAs) are frequently used as second-line therapy, although there is little clinical guidance on the timing of their administration and on tapering/discontinuation of the drug. To provide clinical recommendations, we used the Delphi technique to obtain consensus for statements regarding administration and on tapering/discontinuation of second-line TPO-RAs among a group of Italian clinicians with expertise in management of ITP. METHODS: The Delphi process was used to obtain agreement on five statements regarding initiation and on tapering/discontinuation of second-line TPO-RAs. Agreement was considered when 75% of participants approved the statement. Eleven experts participated in the voting. RESULTS: Full consensus was reached for three of the five statements. The experts held that an early switch from corticosteroids to a TPO-RA has the dual advantage of sparing patients from corticosteroid abuse and improve long-term clinical outcomes. All felt that dose reduction of TPO-RAs can be considered in patients with a stable response and platelet count >100 × 109/L that is maintained for at least 6 months in the absence of concomitant treatments, although there was less agreement in patients with a platelet count >50 × 109/L. Near consensus was reached regarding the statement that early treatment with a TPO-RA is associated with an increase in clinically significant partial or complete response. The experts also agreed that optimization of tapering and discontinuation of TPO-RA therapy in selected patients can improve the quality of life. CONCLUSION: The present consensus can help to provide guidance on use of TPO-RAs in daily practice in patients with ITP. PLAIN LANGUAGE SUMMARY: Second-line administration of thrombopoietin receptor agonists in immune thrombocytopenia There is little guidance on the timing of administration and tapering/discontinuation of thrombopoietin receptor agonists (TPO-RAs) in patients with primary immune thrombocytopenia (ITP).The Delphi technique was used to obtain consensus for five statements.The present consensus among Italian clinicians aims to provide guidance on second-line use of TPO-RAs for patients with ITP in daily practice.
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BACKGROUND: The incidence of peripherally inserted central catheter (PICC)-related adverse events has been uncertain in the setting of acute myeloid leukemia (AML) compared with the incidence of centrally inserted central catheter (CICC) adverse events. PATIENTS AND METHODS: We conducted a monocentric, randomized trial of patients with previously untreated AML. Of the 93 patients, 46 had received a PICC and 47 had received a CICC as frontline intravascular device. Thereafter, all patients underwent intensive chemotherapy for hematologic remission induction. The primary endpoint was catheter-related (CR)-bloodstream infection (BSI) and venous thrombosis (VT) rate. The secondary endpoints catheter malfunction, catheter removal, and patient overall survival. RESULTS: The CR-BSI and CR-VT rate in the PICC and CICC groups was 13% and 49%, respectively, with a difference of 36 percentage points (relative risk for CR-BSI or CR-VT, 0.266; P = .0003). The CR-BSI incidence was 1.4 and 7.8 per 1000 catheters daily in the PICC and CICC groups, respectively. Among the CR thromboses, the symptomatic VT rate was 2.1% in the PICC group and 10.6% in the CICC group. In the CICC group, 16 of the 47 patients (34%) had the catheter removed for BSI (n = 5), septic thrombophlebitis (n = 4), VT (n = 2), or malfunction (n = 5) a median of 7 days after insertion. In the PICC group, only 6 of the 46 patients (13%) required catheter removal for VT (n = 2) or malfunction (n = 4). At a median follow-up of 30 days, 6 patients in the CICC group died of CR complications versus none of the patients in the PICC group (P = .012). Using PICCs, the reduction in BSI and symptomatic VT decreased mortality from CR infection and venous thromboembolism. In contrast, the CICC approach led to early catheter removal mostly for difficult-to-treat infectious pathogens. CONCLUSION: Our data have confirmed that BSI and symptomatic VT are the major complications affecting frontline central intravascular device-related morbidity in the leukemia setting. The use of a PICC is safer than that of a CICC and maintains the effectiveness for patients with AML undergoing chemotherapy, with an approximate fourfold lower combined risk of infection or thrombosis at 30 days.
Assuntos
Cateterismo Venoso Central/efeitos adversos , Cateterismo Periférico/efeitos adversos , Leucemia Mieloide Aguda/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/epidemiologia , Bacteriemia/etiologia , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/etiologia , Cateteres Venosos Centrais/efeitos adversos , Feminino , Humanos , Incidência , Quimioterapia de Indução , Leucemia Mieloide Aguda/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Resultado do Tratamento , Trombose Venosa/epidemiologia , Trombose Venosa/etiologia , Adulto JovemRESUMO
BACKGROUND: Loss of response to transforming growth factor-beta (TGF-beta ) is thought to contribute to the progression of chronic lymphocytic leukemia. Recent findings of over-activation of the TGF-beta signal in FKBP12-knockout mouse prompted us to investigate whether FK506, the canonical ligand of FKBP, can activate the TGF-beta signal in chronic lymphocytic leukemia. DESIGN AND METHODS: We studied 62 chronic lymphocytic leukemia samples from patients with Rai/Binet stage 0 to 4 disease. The TGF-beta signal was investigated by western blotting and flow cytometry. The levels of Bcl2-family members and death-associated-protein kinase were also investigated by western blotting, whereas apoptosis was studied in flow cytometry. Down-modulation of FKBP12 was obtained by gene silencing with short interfering RNA. RESULTS: Twenty-two out of 62 chronic lymphocytic leukemia samples were sensitive to TGF-beta-induced apoptosis. All but two of the responsive samples underwent apoptosis also when cultured with FK506, but not with cyclosporine. Thirteen samples that were not sensitive to TGF-beta were sensitive to FK506. Overall, response to FK506 occurred in 33 samples. FK506 induced Smad2 phosphorylation and nuclear translocation. Accordingly, death-associated-protein kinase, a transcriptional target of Smad, was induced. At the same time, Bcl-2 and Bcl-xL levels decreased whereas the levels of Bim and Bmf increased. A loss of mitochondrial membrane potential preceded caspase activation and cell death. FK506 removed FKBP12 from its binding to the TGF-beta-receptor. FKBP12 release activated the receptor-kinase activity as suggested by the enhanced levels of phospho-Smad found in cells depleted of FKBP12. CONCLUSIONS: Our study shows that most chronic lymphocytic leukemia cells escape the homeostatic control of TGF-beta and that FK506 restores the TGF-beta signal in a proportion of non-responsive samples. We demonstrated that FK506 activates TGF-beta receptor I kinase activity in chronic lymphocytic leukemia, which transduces apoptosis by a mitochondrial-dependent pathway.
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Apoptose , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Tacrolimo/farmacologia , Fator de Crescimento Transformador beta/metabolismo , Progressão da Doença , Humanos , Imunossupressores/farmacologia , Cinética , Leucemia Linfocítica Crônica de Células B/patologia , Ligantes , Mitocôndrias/metabolismo , Mutação , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Proteínas de Ligação a Tacrolimo/metabolismo , Proteína bcl-X/metabolismoRESUMO
Chronic lymphocytic leukaemia (CLL) is the most common B-cell malignancy with a variable clinical outcome. Biomarkers of CLL progression are required for optimising prognosis and therapy. The Inhibitor of Bruton's tyrosine kinase-isoform α (IBTKα) gene encodes a substrate receptor of Cullin 3-dependent E3 ubiquitin ligase, and promotes cell survival in response to the reticulum stress. Searching for novel markers of CLL progression, we analysed the expression of IBTKα in the peripheral blood B-cells of CLL patients, before and after first line therapy causing remission. The expression of IBTKα was significantly increased in disease progression, and decreased in remission after chemotherapy. Consistently with a pro-survival action, RNA interference of IBTKα increased the spontaneous and Fludarabine-induced apoptosis of MEC-1 CLL cells, and impaired the cell cycle of DeFew B-lymphoma cells by promoting the arrest in G0/G1 phase and apoptosis. Consistently, RNA interference of IBTKα up regulated the expression of pro-apoptotic genes, including TNF, CRADD, CASP7, BNIP3 and BIRC3. Our results indicate that IBTKα is a novel marker of CLL progression promoting cell growth and resistance to apoptosis. In this view, IBTKα may represent an attractive cancer drug target for counteracting the therapy-resistance of tumour cells.
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Apoptose , Proteínas de Transporte/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Proteínas Adaptadoras de Transdução de Sinal , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linfócitos B/citologia , Linfócitos B/metabolismo , Proteína Adaptadora de Sinalização CRADD/genética , Proteína Adaptadora de Sinalização CRADD/metabolismo , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/genética , Caspase 7/genética , Caspase 7/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Regulação para Cima , Vidarabina/análogos & derivados , Vidarabina/farmacologia , Vidarabina/uso terapêuticoRESUMO
Neutropenic enterocolitis (NEC) is an abdominal infection reported primarily in patients with acute myeloid leukemia (AML) following chemotherapy, especially cytarabine, a notable efficacious cytotoxic agent for AML remission. Specific data regarding the impact of different cytarabine schedules and/or antibacterial regimens for NEC are sparse. The aim of the study was to identify the predictors of outcome within 30 days of NEC onset. NEC episodes were retrospectively pinpointed among 440 patients with newly diagnosed AML hospitalized in our Institution, over a 10-year period, for receiving chemotherapy protocols with 100-6000 mg/m2 daily of cytarabine. Two subgroups, survivors versus nonsurvivors, were compared by using logistic regression analysis. NEC was documented in 100 of 420 (23.8%) analyzed patients: 42.5% had received high-dose cytarabine, whereas 19% and 15% intermediate-dose and standard-dose cytarabine, respectively (P < 0.001). The 30-day NEC attributable mortality rate was 23%. In univariate analysis, antileukemic protocols containing robust dosages of cytarabine were significantly associated with high mortality (P < 0.001); whereas, standard-dose cytarabine and prompt initiation (at the ultrasonographic appearance of intestinal mural thickening) of NEC therapy with antibiotic combinations including tigecycline were significantly associated with low mortality. In multivariate analysis, high-dose cytarabine-containing chemotherapy was the independent predictor of poor outcome (odds ratio [OR]: 0.109; 95% confidence interval [CI]: 0.032-0.364; P < 0.001), whereas ultrasonography-driven NEC therapy with antibiotic regimens including tigecycline was associated with a favorable outcome (OR: 13.161; 95% CI: 1.587-109.17; P = 0.017). Chemotherapy schedules with robust dosages of cytarabine for AML remission are associated with a high rate of NEC incidence and attributable. Vigorous antibacterial therapy, triggered off pathologic ultrasonographic findings, with drug combinations which have broad antimicrobial coverage and good gut penetration, specifically those also including tigecycline, may be effective in improving 30-day survival rate after NEC onset.