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1.
Neuroimmunomodulation ; 31(1): 51-61, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38272012

RESUMO

BACKGROUND: T-cell acute lymphoblastic leukemia (T-ALL) is a malignant hematologic disease caused by the transformation and uncontrolled proliferation of T-cell precursors. T-ALL is generally thought to originate in the thymus since lymphoblasts express phenotypic markers comparable to those described in thymocytes in distinct stages of development. Although around 50% of T-ALL patients present a thymic mass, T-ALL is characterized by peripheral blood and bone marrow involvement, and central nervous system (CNS) infiltration is one of the most severe complications of the disease. SUMMARY: The CNS invasion is related to the expression of specific adhesion molecules and receptors commonly expressed in developing T cells, such as L-selectin, CD44, integrins, and chemokine receptors. Furthermore, T-ALL blasts also express neurotransmitters, neuropeptides, and cognate receptors that are usually present in the CNS and can affect both the brain and thymus, participating in the crosstalk between the organs. KEY MESSAGES: This review discusses how the thymus-brain connections, mediated by innervation and common molecules and receptors, can impact the development and migration of T-ALL blasts, including CNS infiltration.


Assuntos
Encéfalo , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Timo , Humanos , Timo/patologia , Encéfalo/patologia , Encéfalo/metabolismo , Encéfalo/imunologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Animais
2.
Hematol., Transfus. Cell Ther. (Impr.) ; 42(4): 320-325, Oct.-Dec. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1142974

RESUMO

ABSTRACT Background and objective T-cell acute lymphoblastic leukemia (T-ALL) in children represents a high-risk disease. There is a lack of studies assessing the outcome of T-ALL in Hispanic populations, in which it is a rare malignancy. We report the characteristics and results of treatment for childhood T-cell ALL in children over 14 years at a Latin American reference center. Material and methods From January 2005 to December 2018, there occurred the analysis of twenty patients ≤ 16 years of age from a low-income open population diagnosed at a university hospital in Northeast Mexico. Clinical and laboratory characteristics, treatment regimens and outcomes were assessed by scrutinizing clinical records and electronic databases. Diagnosis was confirmed by flow cytometry, including positivity for CD-2, 5, 7 and surface/cytoplasmic CD3. Survival rates were assessed by the Kaplan-Meier method. Results There was a male preponderance (70 %), with a 2.3 male-to-female ratio (p= .074), the median age being 9.5 years. Leucocytes at diagnosis were ≥ 50 × 109/L in 13 (65 %) children, with CNS infiltration in 6 (30 %) and organomegaly in 10 (50 %). The five-year overall survival (OS) was 44.3 % (95 % CI 41.96-46.62), significantly lower in girls, at 20.8 % (95 % CI 17.32-24.51) vs. 53.1 % (95 % CI 50.30-55.82), (p= .035) in boys; there was no sex difference in the event-free survival (EFS) (p= .215). The survival was significantly higher after 2010 (p= .034). Conclusion The T-cell ALL was more frequent in boys, had a higher mortality in girls and the survival has increased over the last decade with improved chemotherapy and supportive care.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Distribuição por Sexo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/terapia , Criança
3.
Cancers (Basel) ; 12(6)2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32471246

RESUMO

Despite remarkable advances in the treatment of T-cell acute lymphoblastic leukemia (T-ALL), relapsed cases are still a major challenge. Moreover, even successful cases often face long-term treatment-associated toxicities. Targeted therapeutics may overcome these limitations. We have previously demonstrated that casein kinase 2 (CK2)-mediated phosphatase and tensin homologue (PTEN) posttranslational inactivation, and consequent phosphatidylinositol 3-kinase (PI3K)/Akt signaling hyperactivation, leads to increased T-ALL cell survival and proliferation. We also revealed the existence of a crosstalk between CK2 activity and the signaling mediated by interleukin 7 (IL-7), a critical leukemia-supportive cytokine. Here, we evaluated the impact of CIGB-300, a the clinical-grade peptide-based CK2 inhibitor CIGB-300 on T-ALL biology. We demonstrate that CIGB-300 decreases the viability and proliferation of T-ALL cell lines and diagnostic patient samples. Moreover, CIGB-300 overcomes IL-7-mediated T-ALL cell growth and viability, while preventing the positive effects of OP9-delta-like 1 (DL1) stromal support on leukemia cells. Signaling and pull-down experiments indicate that the CK2 substrate nucleophosmin 1 (B23/NPM1) and CK2 itself are the molecular targets for CIGB-300 in T-ALL cells. However, B23/NPM1 silencing only partially recapitulates the anti-leukemia effects of the peptide, suggesting that CIGB-300-mediated direct binding to CK2, and consequent CK2 inactivation, is the mechanism by which CIGB-300 downregulates PTEN S380 phosphorylation and inhibits PI3K/Akt signaling pathway. In the context of IL-7 stimulation, CIGB-300 blocks janus kinase / signal transducer and activator of transcription (JAK/STAT) signaling pathway in T-ALL cells. Altogether, our results strengthen the case for anti-CK2 therapeutic intervention in T-ALL, demonstrating that CIGB-300 (given its ability to circumvent the effects of pro-leukemic microenvironmental cues) may be a valid tool for clinical intervention in this aggressive malignancy.

4.
Hematol Transfus Cell Ther ; 42(4): 320-325, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31810895

RESUMO

BACKGROUND AND OBJECTIVE: T-cell acute lymphoblastic leukemia (T-ALL) in children represents a high-risk disease. There is a lack of studies assessing the outcome of T-ALL in Hispanic populations, in which it is a rare malignancy. We report the characteristics and results of treatment for childhood T-cell ALL in children over 14 years at a Latin American reference center. MATERIAL AND METHODS: From January 2005 to December 2018, there occurred the analysis of twenty patients ≤ 16 years of age from a low-income open population diagnosed at a university hospital in Northeast Mexico. Clinical and laboratory characteristics, treatment regimens and outcomes were assessed by scrutinizing clinical records and electronic databases. Diagnosis was confirmed by flow cytometry, including positivity for CD-2, 5, 7 and surface/cytoplasmic CD3. Survival rates were assessed by the Kaplan-Meier method. RESULTS: There was a male preponderance (70 %), with a 2.3 male-to-female ratio (p =  .074), the median age being 9.5 years. Leucocytes at diagnosis were ≥ 50 × 109/L in 13 (65 %) children, with CNS infiltration in 6 (30 %) and organomegaly in 10 (50 %). The five-year overall survival (OS) was 44.3 % (95 % CI 41.96-46.62), significantly lower in girls, at 20.8 % (95 % CI 17.32-24.51) vs. 53.1 % (95 % CI 50.30-55.82), (p = .035) in boys; there was no sex difference in the event-free survival (EFS) (p = .215). The survival was significantly higher after 2010 (p = .034). CONCLUSION: The T-cell ALL was more frequent in boys, had a higher mortality in girls and the survival has increased over the last decade with improved chemotherapy and supportive care.

6.
Front Oncol ; 9: 316, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31338319

RESUMO

T-cell acute lymphoblastic leukemia (T-ALL) is a biologically heterogeneous malignancy, which reflects distinctive stages of T-cell differentiation arrest. We have revisited a cohort of pediatric T-ALL, in order to test if immunophenotypes associated with molecular alterations would predict the patient's outcome. Genetic mutations, translocations and copy number alterations were identified through Sanger sequencing, RT-PCR, FISH and multiplex ligation-dependent probe amplification (MLPA). We defined 8 immunophenotypic T-ALL subtypes through multiparametric flow cytometry: early T-cell precursor (ETP, n = 27), immature (n = 38), early cortical (n = 15), cortical (n = 50), late cortical (n = 53), CD4/CD8 double negative mature (n = 31), double positive mature (n = 35) and simple positive mature (n = 31) T-ALL. Deletions (del) or amplifications (amp) in at least one gene were observed in 87% of cases. The most frequent gene alterations were CDKN2A/Bdel (71.4%), NOTCH1mut (47.6%) and FBXW7mut (17%). ETP-ALL had frequent FLT3mut (22.2%) and SUZ12del (16.7%) (p < 0.001), while CDKN2A/Bdel were rarely found in this subtype (p < 0.001). The early cortical T-ALL subtype had high frequencies of NOTCH1mut and IL7Rmut (71%, 28.6%, respectively), whereas, mature T-ALL with double positive CD4/CD8 had the highest frequencies of STIL-TAL1 (36.7%), LEF1del (27.3%) and CASP8AP2del (22.7%). The co-existence of two groups of T-ALL with NOTCH1mut/IL7Rmut, and with TLX3/SUZ12del/NF1del/IL7Rmut, were characterized with statistical significance (p < 0.05) but only STIL-TAL1 (pOS 47.5%) and NOTCH1WT/FBXW7WT (pOS 55.3%) are predictors of poor T-ALL outcomes. In conclusion, we have observed that 8 T-ALL subgroups are characterized by distinct molecular profiles. The mutations in NOTCH1/FBXW7 and STIL-TAL1 rearrangement had a prognostic impact, independent of immunophenotype.

7.
J Leukoc Biol ; 105(5): 935-946, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30698851

RESUMO

Acute lymphoblastic leukemia (ALL) comprises a heterogeneous group of hematologic malignancies, arising from diverse genetic alterations in the early lymphocyte development. T-cell subtype of ALL (T-ALL) accounts for about 15% and 25% of ALL in children and adults, respectively. Being less frequent among ALL subtypes, T-ALL represents a high-risk factor for poor prognosis due to its aggressiveness and resistance to common antileukemic drugs. Mitochondria were widely explored recently as a target for anticancer treatment because they are involved in a metabolic reprogramming of a cancer cell and play key roles in reactive oxygen species generation, Ca2+ signaling, and cell death induction. Accordingly, a new class of anticancer compounds named mitocans has been developed, which target mitochondria at distinct crucial points to promote their dysfunction and subsequent cell death. The present review analyses the role of mitochondria in malignant reprogramming and emerging therapeutic strategies targeting mitochondria as an "Achilles' heel" in T-ALL, with an emphasis on BH3 mimetics, sequestering pro-survival BCL proteins and voltage-dependent anion channel (VDAC)1-directed drugs, which promote the suppression of aerobic glycolysis, VDAC1 closure, mitochondrial Ca2+ overload, stoppage of the oxidative phosphorylation, oxidative stress, and release of proapoptotic factors.


Assuntos
Antineoplásicos/uso terapêutico , Proteínas Reguladoras de Apoptose/genética , Regulação Leucêmica da Expressão Gênica , Mitocôndrias/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Canal de Ânion 1 Dependente de Voltagem/genética , Adulto , Apoptose/efeitos dos fármacos , Apoptose/genética , Proteínas Reguladoras de Apoptose/agonistas , Proteínas Reguladoras de Apoptose/metabolismo , Cálcio/metabolismo , Sinalização do Cálcio , Transformação Celular Neoplásica , Criança , Glicólise/efeitos dos fármacos , Glicólise/genética , Humanos , Mitocôndrias/metabolismo , Terapia de Alvo Molecular/métodos , Fosforilação Oxidativa/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Linfócitos T/patologia , Canal de Ânion 1 Dependente de Voltagem/antagonistas & inibidores , Canal de Ânion 1 Dependente de Voltagem/metabolismo
8.
Cytokine ; 102: 94-101, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28802664

RESUMO

Leukemic cells can induce defective expression of soluble factors and change marrow cytokine profile, leading to aberrant cell signaling, cell fixation and cell proliferation in bone marrow. T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive disorder which accounts for 15% of pediatric ALL. To evaluate the contribution of immunological factors on T-ALL survival, we measured Th1, Th2, Th17 cytokines and soluble HLA-G (sHLA-G) levels in bone marrow from 32 Brazilian children at diagnosis (D0), after induction (D19) and after consolidation (D49) of the chemotherapy phase. Data were analyzed using non-parametric tests, and survival rates were evaluated by Kaplan-Meier method (log-rank test). TNF, IL-10 and IL-6 levels were increased at diagnosis compared to D19 and D49. IL-10 levels<4.57pg/mL at diagnosis were associated with increased survival rate, in presence of positive correlation between IL-2 and IL-17 levels. Increased survival rate was also associated with IFN-γ levels<1.17pg/mL at D49, with a positive correlation observed between IL-4 and IL-2 as well IL-4 and IL-17 levels. In contrast, worse survival rate was associated with IL-2, IL-4 and IL-10 levels imbalance. In addition, increased sHLA-G levels at diagnosis were associated with increased leukocyte count, a well-known factor for poor prognosis. In conclusion, cytokines and sHLA-G play an essential role in marrow T-ALL microenvironment during chemotherapy, especially the immunosuppressive cytokine IL-10 which can be used as biomarker of disease outcome, being also a potential target for novel T-ALL treatments.


Assuntos
Medula Óssea/imunologia , Citocinas/metabolismo , Antígenos HLA-G/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/imunologia , Adolescente , Biomarcadores Tumorais/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Estimativa de Kaplan-Meier , Masculino , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/mortalidade , Prognóstico , Solubilidade , Taxa de Sobrevida , Microambiente Tumoral/imunologia
9.
Blood Cells Mol Dis ; 57: 74-80, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26852660

RESUMO

With the combination of immunophenotyping and molecular tests, it is still a challenge to identify the characteristics of T cell acute lymphoblastic leukemia (T-ALL) associated with distinct outcomes. This study tests the possible correlation of cellular expression of CD135 and CD117 with somatic gene mutations in T-ALL. One hundred sixty-two samples were tested, including 143 at diagnosis, 15 from T-lymphoblastic lymphoma at relapse, and four relapse samples from sequential follow-up of T-ALL. CD135 and CD117 monoclonal antibodies were included in the T-ALL panel of flow cytometry. The percentage of cells positivity and the median fluorescence intensity were correlated with gene mutational status. STIL-TAL1, TLX3, FLT3 and IL7R mutations were tested using standard techniques. STIL-TAL1 was found in 24.8%, TLX3 in 12%, IL7R in 10% and FLT3-ITD in 5% of cases. FLT3 and IL7R mutations were mutually exclusive, as were FLT3-ITD and STIL-TAL1. Associations of CD135(high) (p<0.01), CD117(intermediate/high) (p=0.02) and FLT3-ITD, CD117(low) with IL7R(mutated) (p<0.01) and CD135(high) with TLX3(pos) were observed. We conclude that the addition of CD135 and CD117 to the diagnosis can predict molecular aberrations in T-ALL settings, mainly segregating patients with FLT3-ITD, who would benefit from treatment with inhibitors of tyrosine.


Assuntos
Biomarcadores Tumorais/genética , Proteínas de Homeodomínio/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proteínas Proto-Oncogênicas c-kit/genética , Receptores de Interleucina-7/genética , Tirosina Quinase 3 Semelhante a fms/genética , Adolescente , Anticorpos Monoclonais , Antineoplásicos/uso terapêutico , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/imunologia , Biomarcadores Tumorais/imunologia , Criança , Pré-Escolar , Feminino , Expressão Gênica , Proteínas de Homeodomínio/imunologia , Humanos , Imunofenotipagem , Lactente , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Masculino , Mutação , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/imunologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/imunologia , Proteínas Proto-Oncogênicas c-kit/imunologia , Receptores de Interleucina-7/imunologia , Recidiva , Proteína 1 de Leucemia Linfocítica Aguda de Células T , Adulto Jovem , Tirosina Quinase 3 Semelhante a fms/imunologia
10.
Cancer Sci ; 106(10): 1264-77, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26251039

RESUMO

Recent evidence has shown that deregulated expression of members of the microRNA-29 (miR-29) family may play a critical role in human cancer, including hematological malignancies. However, the roles of miR-29 in the molecular pathophysiology of T-cell acute lymphoblastic leukemia (T-ALL) has not been investigated. Here, we show that lower levels of miR-29a were significantly associated with higher blast counts in the bone marrow and with increased disease-free survival in T-ALL patients. Furthermore, miR-29a levels are extremely reduced in T-ALL cells compared to normal T cells. Microarray analysis following introduction of synthetic miR-29a mimics into Jurkat cells revealed the downregulation of several predicted targets (CDK6, PXDN, MCL1, PIK3R1, and CXXC6), including targets with roles in active and passive DNA demethylation (such as DNMT3a, DNMT3b, and members of the TET family and TDG). Restoring miR-29a levels in Jurkat and Molt-4 T-ALL cells led to the demethylation of many genes commonly methylated in T-ALL. Overall, our results suggest that reduced miR-29a levels may contribute to the altered epigenetic status of T-ALL, highlighting its relevance in the physiopathology of this disease.


Assuntos
Metilação de DNA/genética , Epigênese Genética/genética , Regulação Leucêmica da Expressão Gênica/genética , MicroRNAs/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Antígenos de Neoplasias/biossíntese , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Classe Ia de Fosfatidilinositol 3-Quinase , Quinase 6 Dependente de Ciclina/biossíntese , DNA (Citosina-5-)-Metiltransferases/genética , DNA Metiltransferase 3A , Proteínas de Ligação a DNA/biossíntese , Daunorrubicina/farmacologia , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Células Jurkat , Oxigenases de Função Mista , Proteína de Sequência 1 de Leucemia de Células Mieloides/biossíntese , Análise de Sequência com Séries de Oligonucleotídeos , Peroxidases , Fosfatidilinositol 3-Quinases/biossíntese , Proteínas Proto-Oncogênicas/biossíntese , Receptores de Interleucina-1/biossíntese , DNA Metiltransferase 3B
11.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;41(5): 344-350, May 2008. ilus
Artigo em Inglês | LILACS | ID: lil-484442

RESUMO

T-cell acute lymphoblastic leukemia (T-ALL) is a biologically heterogeneous disease with respect to phenotype, gene expression profile and activation of particular intracellular signaling pathways. Despite very significant improvements, current therapeutic regimens still fail to cure a portion of the patients and frequently implicate the use of aggressive protocols with long-term side effects. In this review, we focused on how deregulation of critical signaling pathways, in particular Notch, PI3K/Akt, MAPK, Jak/STAT and TGF-ß, may contribute to T-ALL. Identifying the alterations that affect intracellular pathways that regulate cell cycle and apoptosis is essential to understanding the biology of this malignancy, to define more effective markers for the correct stratification of patients into appropriate therapeutic regimens and to identify novel targets for the development of specific, less detrimental therapies for T-ALL.


Assuntos
Humanos , Diferenciação Celular , Leucemia-Linfoma de Células T do Adulto , Fosfotransferases/fisiologia , Transdução de Sinais/fisiologia , Linfócitos T/citologia , /fisiologia , Janus Quinases/fisiologia , Leucemia-Linfoma de Células T do Adulto/etiologia , Leucemia-Linfoma de Células T do Adulto/fisiopatologia , Leucemia-Linfoma de Células T do Adulto/terapia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/fisiologia , Receptores Notch/fisiologia , Fator de Crescimento Transformador beta/fisiologia
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