RESUMO
Liquid biopsy has recently emerged as an important tool in clinical practice particularly for lung cancer patients. We retrospectively evaluated cell-free DNA analyses performed at our Institution by next generation sequencing methodology detecting the major classes of genetic alterations. Starting from the graphical representation of chromosomal alterations provided by the analysis software, we developed a support vector machine classifier to automatically classify chromosomal profiles as stable (SCP) or unstable (UCP). High concordance was found between our binary classification and tumor fraction evaluation performed using shallow whole genome sequencing. Among clinical features, UCP patients were more likely to have ≥ 3 metastatic sites and liver metastases. Longitudinal assessment of chromosomal profiles in 33 patients with lung cancer receiving immune checkpoint inhibitors (ICIs) showed that only patients that experienced early death or hyperprogressive disease retained or acquired an UCP within 3 weeks from the beginning of ICIs. UCP was not observed following ICIs among patients that experienced progressive disease or clinical benefit. In conclusion, our binary classification, applied to whole copy number alteration profiles, could be useful for clinical risk stratification during systemic treatment for non-small cell lung cancer patients.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Variações do Número de Cópias de DNA , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Masculino , Feminino , Biópsia Líquida/métodos , Idoso , Pessoa de Meia-Idade , Estudos Retrospectivos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Inibidores de Checkpoint Imunológico/uso terapêutico , Idoso de 80 Anos ou mais , Máquina de Vetores de SuporteRESUMO
While the genomics era has allowed remarkable advances in understanding the mechanisms driving the biology and pathogenesis of numerous blood cancers, including acute lymphoblastic leukemia (ALL), metabolic studies are still lagging, especially regarding how the metabolism differs between healthy and diseased individuals. T-cell ALL (T-ALL) is an aggressive hematological neoplasm deriving from the malignant transformation of T-cell progenitors characterized by frequent NOTCH1 pathway activation. The aim of our study was to characterize tumor and plasma metabolomes during T-ALL development using a NOTCH1-induced murine T-ALL model (ΔE-NOTCH1). In tissue, we found a significant metabolic shift with leukemia development, as metabolites linked to glycolysis (lactic acid) and Tricarboxylic acid cycle replenishment (succinic and malic acids) were elevated in NOTCH1 tumors, while metabolites associated with lipid oxidation (e.g., carnitine) as well as purine and pyrimidine metabolism were elevated in normal thymic tissue. Glycine, serine, and threonine metabolism, glutathione metabolism, as well as valine, leucine, and isoleucine biosynthesis were enriched pathways in tumor tissue. Phenylalanine and tyrosine metabolism was highly enriched in plasma from leukemia-bearing mice compared to healthy mice. Further, we identified a metabolic signature consisting of glycine, alanine, proline, 3-hydroxybutyrate, and glutamic acid as potential biomarkers for leukemia progression in plasma. Hopefully, the metabolic differences detected in our leukemia model will apply to humans and contribute to the development of metabolism-oriented therapeutic approaches.
Assuntos
Biomarcadores Tumorais , Metabolômica , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Receptor Notch1 , Animais , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/sangue , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Camundongos , Receptor Notch1/metabolismo , Metabolômica/métodos , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/metabolismo , Metaboloma , Modelos Animais de DoençasRESUMO
Genetic screening of somatic mutations in circulating free DNA (cfDNA) opens up new opportunities for personalized medicine. In this study, we aim to illustrate the implementation of NGS-based liquid biopsy in clinical practice for the detection of somatic alterations in selected genes. Our work is particularly relevant for the diagnosis and treatment of NSCLC. Beginning in 2020, we implemented the use of Roche's Avenio ctDNA expanded panel in our diagnostic routine. In this study, we retrospectively review NGS-based clinical genetic tests performed in our laboratory, focusing on key analytical parameters. Avenio ctDNA kits demonstrated 100% sensitivity in detecting single nucleotide variants (SNVs) at >0.5% variant allele frequency (VAF), and high consistency in reproducibility. Since 2020, we performed cfDNA genotyping test in 86 NSCLC patients, and we successfully sequenced 96.5% (83/86) of samples. We observed consistency in sequencing performance based upon sequencing depth and on-target rate. At least one gene variant was identified in 52 samples (63%), and one or more actionable variants were detected in 21 out of 83 (25%) of analysed patients. We demonstrated the feasibility of implementing an NGS-based liquid biopsy assay for routine genetic characterization of metastatic NSCLC patients.
RESUMO
Acute leukemias, classified as acute myeloid leukemia and acute lymphoblastic leukemia, represent the most prevalent hematologic tumors in adolescent and young adults. In recent years, new challenges have emerged in order to improve the clinical effectiveness of therapies already in use and reduce their side effects. In particular, in this scenario, metabolic reprogramming plays a key role in tumorigenesis and prognosis, and it contributes to the treatment outcome of acute leukemia. This review summarizes the latest findings regarding the most relevant metabolic pathways contributing to the continuous growth, redox homeostasis, and drug resistance of leukemia cells. We describe the main metabolic deregulations in acute leukemia and evidence vulnerabilities that could be exploited for targeted therapy.
Assuntos
Antineoplásicos/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Terapia de Alvo Molecular , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Resultado do Tratamento , Adulto JovemRESUMO
Numerous studies have shown that hedgehog inhibitors (iHHs) only partially block the growth of tumor cells, especially in vivo. Leukemia often expands in a nutrient-depleted environment (bone marrow and thymus). In order to identify putative signaling pathways implicated in the adaptive response to metabolically adverse conditions, we executed quantitative phospho-proteomics in T-cell acute lymphoblastic leukemia (T-ALL) cells subjected to nutrient-depleted conditions (serum starvation). We found important modulations of peptides phosphorylated by critical signaling pathways including casein kinase, mammalian target of rapamycin, and 5'AMP-activated kinase (AMPK). Surprisingly, in T-ALL cells, AMPK signaling was the most consistently downregulated pathway under serum-depleted conditions, and this coincided with increased GLI1 expression and sensitivity to iHHs, especially the GLI1/2 inhibitor GANT-61. Increased sensitivity to GANT-61 was also found following genetic inactivation of the catalytic subunit of AMPK (AMPKα1) or pharmacological inhibition of AMPK by Compound C. Additionally, patient-derived xenografts showing high GLI1 expression lacked activated AMPK, suggesting an important role for this signaling pathway in regulating GLI1 protein levels. Further, joint targeting of HH and AMPK signaling pathways in T-ALL cells by GANT-61 and Compound C significantly increased the therapeutic response. Our results suggest that metabolic adaptation that occurs under nutrient starvation in T-ALL cells increases responsiveness to HH pathway inhibitors through an AMPK-dependent mechanism and that joint therapeutic targeting of AMPK signaling and HH signaling could represent a valid therapeutic strategy in rapidly expanding tumors where nutrient availability becomes limiting.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Hedgehog/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Transdução de Sinais , Proteínas Quinases Ativadas por AMP/genética , Morte Celular/efeitos dos fármacos , Meios de Cultura Livres de Soro/farmacologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Células Jurkat , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Piridinas/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteína GLI1 em Dedos de Zinco/metabolismoRESUMO
T-cell acute lymphoblastic leukemia (T-ALL) is a highly malignant pediatric leukemia, where few therapeutic options are available for patients which relapse. We find that therapeutic targeting of GLI transcription factors by GANT-61 is particularly effective against NOTCH1 unmutated T-ALL cells. Investigation of the functional role of GLI1 disclosed that it contributes to T-ALL cell proliferation, survival, and dissemination through the modulation of AKT and CXCR4 signaling pathways. Decreased CXCR4 signaling following GLI1 inactivation was found to be prevalently due to post-transcriptional mechanisms including altered serine 339 CXCR4 phosphorylation and cortactin levels. We also identify a novel cross-talk between GLI transcription factors and FOXC1. Indeed, GLI factors can activate the expression of FOXC1 which is able to stabilize GLI1/2 protein levels through attenuation of their ubiquitination. Further, we find that prolonged GLI1 deficiency has a double-edged role in T-ALL progression favoring disease dissemination through the activation of a putative AKT/FOXC1/GLI2 axis. These findings have clinical significance as T-ALL patients with extensive central nervous system dissemination show low GLI1 transcript levels. Further, T-ALL patients having a GLI2-based Hedgehog activation signature are associated with poor survival. Together, these findings support a rationale for targeting the FOXC1/AKT axis to prevent GLI-dependent oncogenic Hedgehog signaling.
Assuntos
Fatores de Transcrição Forkhead/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Transdução de Sinais , Proteína GLI1 em Dedos de Zinco/metabolismo , Animais , Apoptose , Biópsia , Pontos de Checagem do Ciclo Celular , Biologia Computacional/métodos , Modelos Animais de Doenças , Progressão da Doença , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Proteínas Hedgehog/metabolismo , Humanos , Imuno-Histoquímica , Camundongos , Mutação , Leucemia-Linfoma Linfoblástico de Células T Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/etiologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/mortalidade , Prognóstico , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptores CXCR4/metabolismo , Fatores de TranscriçãoRESUMO
Notwithstanding intensified therapy, a considerable fraction of T-cell acute lymphoblastic leukemia (T-ALL) patients face a dismal prognosis due to primary resistance to treatment and relapse, raising the need for more efficient and targeted therapies. Hedgehog (HH) signaling is a major developmental pathway frequently deregulated in cancer, for which a role in T-ALL is emerging. Mounting evidence suggests that ligand-independent activation of HH pathway occurs in cancer including T-ALL, emphasizing the necessity of dissecting the complex interplay between HH and other signaling pathways regulating activation. In this work, we present a therapeutically relevant crosstalk between HH signaling and the glucocorticoid receptor (NR3C1) pathway acting at the level of GLI1 transcription factor. GLI inhibitor GANT61 and dexamethasone were shown to exert a synergistic anti-leukemic effect in vitro in T-ALL cell lines and patient-derived xenografts. Mechanistically, dexamethasone-activated NR3C1 impaired GLI1 function by dynamically modulating the recruitment of PCAF acetyltransferase and HDAC1 deacetylase. Increased GLI1 acetylation was associated with compromised transcriptional activity and reduced protein stability. In summary, our study identifies a novel crosstalk between GLI1 and NR3C1 signaling pathway which could be exploited in HH-dependent malignancies to increase therapeutic efficacy.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proteínas Hedgehog/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Receptores de Glucocorticoides/metabolismo , Transdução de Sinais/efeitos dos fármacos , Acetilação , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Sinergismo Farmacológico , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Proteínas Hedgehog/antagonistas & inibidores , Histona Desacetilase 1/metabolismo , Humanos , Camundongos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Estabilidade Proteica/efeitos dos fármacos , Piridinas/farmacologia , Piridinas/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Receptores de Glucocorticoides/agonistas , Transdução de Sinais/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína GLI1 em Dedos de Zinco/antagonistas & inibidores , Proteína GLI1 em Dedos de Zinco/metabolismo , Fatores de Transcrição de p300-CBP/metabolismoRESUMO
T-cell acute lymphoblastic leukemia (T-ALL) is a rare, aggressive disease arising from T-cell precursors. NOTCH1 plays an important role both in T-cell development and leukemia progression, and more than 60% of human T-ALLs harbor mutations in components of the NOTCH1 signaling pathway, leading to deregulated cell growth and contributing to cell transformation. Besides multiple NOTCH1 target genes, microRNAs have also been shown to regulate T-ALL initiation and progression. Using an established mouse model of T-ALL induced by NOTCH1 activation, we identified several microRNAs downstream of NOTCH1 activation. In particular, we found that NOTCH1 inhibition can induce miR-22-3p in NOTCH1-dependent tumors and that this regulation is also conserved in human samples. Importantly, miR-22-3p overexpression in T-ALL cells can inhibit colony formation in vitro and leukemia progression in vivo. In addition, miR-22-3p was found to be downregulated in T-ALL specimens, both T-ALL cell lines and primary samples, relative to immature T-cells. Our results suggest that miR-22-3p is a functionally relevant microRNA in T-ALL whose modulation can be exploited for therapeutic purposes to inhibit T-ALL progression.
Assuntos
Progressão da Doença , MicroRNAs/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Leucêmica da Expressão Gênica , Humanos , Camundongos , MicroRNAs/genética , Receptor Notch1/antagonistas & inibidores , Receptor Notch1/metabolismo , Regulação para Cima/genéticaRESUMO
Multi-agent combination chemotherapy can be curative in acute lymphoblastic leukemia (ALL). Still, patients with primary refractory disease or with relapsed leukemia have a very poor prognosis. Here we integrate an in-depth dissection of the mutational landscape across diagnostic and relapsed pediatric and adult ALL samples with genome-wide CRISPR screen analysis of gene-drug interactions across seven ALL chemotherapy drugs. By combining these analyses, we uncover diagnostic and relapse-specific mutational mechanisms as well as genetic drivers of chemoresistance. Functionally, our data identifies common and drug-specific pathways modulating chemotherapy response and underscores the effect of drug combinations in restricting the selection of resistance-driving genetic lesions. In addition, by identifying actionable targets for the reversal of chemotherapy resistance, these analyses open novel therapeutic opportunities for the treatment of relapse and refractory disease.
Assuntos
Resistencia a Medicamentos Antineoplásicos , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto , Criança , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Mutação , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Prognóstico , RecidivaRESUMO
MYC-translocated T-lineage acute lymphoblastic leukemia (T-ALL) is a rare subgroup of T-ALL associated with CDKN2A/B deletions, PTEN inactivation, and absence of NOTCH1 or FBXW7 mutations. This subtype of T-ALL has been associated with induction failure and aggressive disease. Identification of drug targets and mechanistic insights for this disease are still limited. Here, we established a human NOTCH1-independent MYC-translocated T-ALL cell line that maintains the genetic and phenotypic characteristics of the parental leukemic clone at diagnosis. The University of Padua T-cell acute lymphoblastic leukemia 13 (UP-ALL13) cell line has all the main features of the above described MYC-translocated T-ALL. Interestingly, UP-ALL13 was found to harbor a heterozygous R882H DNMT3A mutation typically found in myeloid leukemia. Chromatin immunoprecipitation coupled with high-throughput sequencing for histone H3 lysine 27 (H3K27) acetylation revealed numerous putative super-enhancers near key transcription factors, including MYC, MYB, and LEF1. Marked cytotoxicity was found following bromodomain-containing protein 4 (BRD4) inhibition with AZD5153, suggesting a strict dependency of this particular subtype of T-ALL on the activity of super-enhancers. Altogether, this cell line may be a useful model system for dissecting the signaling pathways implicated in NOTCH1-independent T-ALL and for the screening of targeted anti-leukemia agents specific for this T-ALL subgroup.
RESUMO
The NOTCH signaling pathway is a conserved signaling cascade that regulates many aspects of development and homeostasis in multiple organ systems. Aberrant activity of this signaling pathway is linked to the initiation and progression of several hematological malignancies, exemplified by T-cell acute lymphoblastic leukemia (T-ALL). Interestingly, frequent non-mutational activation of NOTCH1 signaling has recently been demonstrated in B-cell chronic lymphocytic leukemia (B-CLL), significantly extending the pathogenic significance of this pathway in B-CLL. Leukemia patients often present with high-blood cell counts, diffuse disease with infiltration of the bone marrow, secondary lymphoid organs, and diffusion to the central nervous system (CNS). Chemokines are chemotactic cytokines that regulate migration of cells between tissues and the positioning and interactions of cells within tissue. Homeostatic chemokines and their receptors have been implicated in regulating organ-specific infiltration, but may also directly and indirectly modulate tumor growth. Recently, oncogenic NOTCH1 has been shown to regulate infiltration of leukemic cells into the CNS hijacking the CC-chemokine ligand 19/CC-chemokine receptor 7 chemokine axis. In addition, a crucial role for the homing receptor axis CXC-chemokine ligand 12/CXC-chemokine receptor 4 has been demonstrated in leukemia maintenance and progression. Moreover, the CCL25/CCR9 axis has been implicated in the homing of leukemic cells into the gut, particularly in the presence of phosphatase and tensin homolog tumor suppressor loss. In this review, we summarize the latest developments regarding the role of NOTCH signaling in regulating the chemotactic microenvironmental cues involved in the generation and progression of T-ALL and compare these findings to B-CLL.
Assuntos
Sistema Nervoso Central/imunologia , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/imunologia , Receptor Notch1/metabolismo , Animais , Carcinogênese , Movimento Celular , Quimiocinas/metabolismo , Quimiotaxia , Humanos , Transdução de Sinais , Microambiente TumoralRESUMO
Loss-of-function mutations and deletions in Wilms tumor 1 (WT1) gene are present in approximately 10% of T-cell acute lymphoblastic leukemia. Clinically, WT1 mutations are enriched in relapsed series and are associated to inferior relapse-free survival in thymic T-cell acute lymphoblastic leukemia cases. Here we demonstrate that WT1 plays a critical role in the response to DNA damage in T-cell leukemia. WT1 loss conferred resistance to DNA damaging agents and attenuated the transcriptional activation of important apoptotic regulators downstream of TP53 in TP53-competent MOLT4 T-leukemia cells but not in TP53-mutant T-cell acute lymphoblastic leukemia cell lines. Notably, WT1 loss positively affected the expression of the X-linked inhibitor of apoptosis protein, XIAP, and genetic or chemical inhibition with embelin (a XIAP inhibitor) significantly restored sensitivity to γ-radiation in both T-cell acute lymphoblastic leukemia cell lines and patient-derived xenografts. These results reveal an important role for the WT1 tumor suppressor gene in the response to DNA damage, and support the view that anti-XIAP targeted therapies could have a role in the treatment of WT1-mutant T-cell leukemia.
Assuntos
Dano ao DNA/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proteína Supressora de Tumor p53/efeitos dos fármacos , Proteínas WT1/deficiência , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta à Radiação , Raios gama , Xenoenxertos , Humanos , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Proteínas Inibidoras de Apoptose/fisiologia , Camundongos SCID , Leucemia-Linfoma Linfoblástico de Células T Precursoras/radioterapia , Proteína Supressora de Tumor p53/fisiologia , Proteínas WT1/fisiologiaRESUMO
Calcineurin (Cn) is a calcium activated protein phosphatase involved in many aspects of normal T cell physiology, however the role of Cn and/or its downstream targets in leukemogenesis are still ill-defined. In order to identify putative downstream targets/effectors involved in the pro-oncogenic activity of Cn in T-cell acute lymphoblastic leukemia (T-ALL) we used tandem affinity chromatography, followed by mass spectrometry to purify novel Cn-interacting partners. We found the Cn-interacting proteins to be part of numerous cellular signaling pathways including eIF2 signaling and mTOR signaling. Coherently, modulation of Cn activity in T-ALL cells determined alterations in the phosphorylation status of key molecules implicated in protein translation such as eIF-2α and ribosomal protein S6. Joint targeting of PI3K-mTOR, eIF-2α and 14-3-3 signaling pathways with Cn unveiled novel synergistic pro-apoptotic drug combinations. Further analysis disclosed that the synergistic interaction between PI3K-mTOR and Cn inhibitors was prevalently due to AKT inhibition. Finally, we showed that the synergistic pro-apoptotic response determined by jointly targeting AKT and Cn pathways was linked to down-modulation of key anti-apoptotic proteins including Mcl-1, Claspin and XIAP. In conclusion, we identify AKT inhibition as a novel promising drug combination to potentiate the pro-apoptotic effects of Cn inhibitors.
Assuntos
Calcineurina/metabolismo , Fatores de Transcrição NFATC/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Transdução de Sinais/fisiologia , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Inibidores de Calcineurina/farmacologia , Linhagem Celular Tumoral , Ciclosporina/farmacologia , Compostos Heterocíclicos com 3 Anéis/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Activating mutations in NOTCH1 are common in T cell acute lymphoblastic leukemia (T-ALL). Here we identify glutaminolysis as a critical pathway for leukemia cell growth downstream of NOTCH1 and a key determinant of the response to anti-NOTCH1 therapies in vivo. Mechanistically, inhibition of NOTCH1 signaling in T-ALL induces a metabolic shutdown, with prominent inhibition of glutaminolysis and triggers autophagy as a salvage pathway supporting leukemia cell metabolism. Consequently, inhibition of glutaminolysis and inhibition of autophagy strongly and synergistically enhance the antileukemic effects of anti-NOTCH1 therapy in mice harboring T-ALL. Moreover, we demonstrate that Pten loss upregulates glycolysis and consequently rescues leukemic cell metabolism, thereby abrogating the antileukemic effects of NOTCH1 inhibition. Overall, these results identify glutaminolysis as a major node in cancer metabolism controlled by NOTCH1 and as therapeutic target for the treatment of T-ALL.
Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Receptor Notch1/antagonistas & inibidores , Animais , Glutamina/metabolismo , Camundongos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismoRESUMO
Somatic mutations in IDH1/IDH2 and TET2 result in impaired TET2-mediated conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). The observation that WT1 inactivating mutations anticorrelate with TET2/IDH1/IDH2 mutations in acute myeloid leukemia (AML) led us to hypothesize that WT1 mutations may impact TET2 function. WT1 mutant AML patients have reduced 5hmC levels similar to TET2/IDH1/IDH2 mutant AML. These mutations are characterized by convergent, site-specific alterations in DNA hydroxymethylation, which drive differential gene expression more than alterations in DNA promoter methylation. WT1 overexpression increases global levels of 5hmC, and WT1 silencing reduced 5hmC levels. WT1 physically interacts with TET2 and TET3, and WT1 loss of function results in a similar hematopoietic differentiation phenotype as observed with TET2 deficiency. These data provide a role for WT1 in regulating DNA hydroxymethylation and suggest that TET2 IDH1/IDH2 and WT1 mutations define an AML subtype defined by dysregulated DNA hydroxymethylation.
Assuntos
Proteínas de Ligação a DNA/fisiologia , Regulação Neoplásica da Expressão Gênica , Leucemia Mieloide Aguda/genética , Proteínas Proto-Oncogênicas/fisiologia , Proteínas WT1/genética , 5-Metilcitosina/análogos & derivados , Animais , Diferenciação Celular , Citosina/análogos & derivados , Citosina/fisiologia , Dioxigenases , Elementos Facilitadores Genéticos , Hematopoese , Humanos , Leucemia Mieloide Aguda/metabolismo , Camundongos Knockout , Mutação , Regiões Promotoras Genéticas , Ligação Proteica , Análise de Sequência de DNARESUMO
Glucocorticoid resistance is a major driver of therapeutic failure in T cell acute lymphoblastic leukemia (T-ALL). Here, we identify the AKT1 kinase as a major negative regulator of the NR3C1 glucocorticoid receptor protein activity driving glucocorticoid resistance in T-ALL. Mechanistically, AKT1 impairs glucocorticoid-induced gene expression by direct phosphorylation of NR3C1 at position S134 and blocking glucocorticoid-induced NR3C1 translocation to the nucleus. Moreover, we demonstrate that loss of PTEN and consequent AKT1 activation can effectively block glucocorticoid-induced apoptosis and induce resistance to glucocorticoid therapy. Conversely, pharmacologic inhibition of AKT with MK2206 effectively restores glucocorticoid-induced NR3C1 translocation to the nucleus, increases the response of T-ALL cells to glucocorticoid therapy, and effectively reverses glucocorticoid resistance in vitro and in vivo.
Assuntos
Dexametasona/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/farmacologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Transporte Ativo do Núcleo Celular , Animais , Resistencia a Medicamentos Antineoplásicos , Humanos , Camundongos , PTEN Fosfo-Hidrolase/fisiologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/fisiologia , Receptores de Glucocorticoides/metabolismoRESUMO
T-cell acute lymphoblastic leukemia/lymphoma (T-ALL) is characterized by aberrant activation of NOTCH1 in over 60% of T-ALL cases. The high prevalence of activating NOTCH1 mutations highlights the critical role of NOTCH signaling in the pathogenesis of this disease and has prompted the development of therapeutic approaches targeting the NOTCH signaling pathway. Small molecule gamma secretase inhibitors (GSIs) can effectively inhibit oncogenic NOTCH1 and are in clinical testing for the treatment of T-ALL. Treatment with GSIs and glucocorticoids are strongly synergistic and may overcome the gastrointestinal toxicity associated with systemic inhibition of the NOTCH pathway. In addition, emerging new anti-NOTCH1 therapies include selective inhibition of NOTCH1 with anti-NOTCH1 antibodies and stapled peptides targeting the NOTCH transcriptional complex in the nucleus.
RESUMO
Acute lymphoblastic leukemia (ALL) is an aggressive hematological tumor resulting from the malignant transformation of lymphoid progenitors. Despite intensive chemotherapy, 20% of pediatric patients and over 50% of adult patients with ALL do not achieve a complete remission or relapse after intensified chemotherapy, making disease relapse and resistance to therapy the most substantial challenge in the treatment of this disease. Using whole-exome sequencing, we identify mutations in the cytosolic 5'-nucleotidase II gene (NT5C2), which encodes a 5'-nucleotidase enzyme that is responsible for the inactivation of nucleoside-analog chemotherapy drugs, in 20/103 (19%) relapse T cell ALLs and 1/35 (3%) relapse B-precursor ALLs. NT5C2 mutant proteins show increased nucleotidase activity in vitro and conferred resistance to chemotherapy with 6-mercaptopurine and 6-thioguanine when expressed in ALL lymphoblasts. These results support a prominent role for activating mutations in NT5C2 and increased nucleoside-analog metabolism in disease progression and chemotherapy resistance in ALL.
Assuntos
5'-Nucleotidase/genética , Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Mercaptopurina/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , 5'-Nucleotidase/metabolismo , Arabinonucleosídeos/farmacologia , Arabinonucleosídeos/uso terapêutico , Sequência de Bases , Linhagem Celular , Células HEK293 , Humanos , Mutação , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Recidiva , Análise de Sequência de DNA , Tioguanina/uso terapêuticoRESUMO
Constitutive phosphoinositide 3-kinase (PI3K)/Akt activation is common in T cell acute lymphoblastic leukemia (T-ALL). Although four distinct class I PI3K isoforms (α, ß, γ, δ) could participate in T-ALL pathogenesis, none has been implicated in this process. We report that in the absence of PTEN phosphatase tumor suppressor function, PI3Kγ or PI3Kδ alone can support leukemogenesis, whereas inactivation of both isoforms suppressed tumor formation. The reliance of PTEN null T-ALL on the combined activities of PI3Kγ/δ was further demonstrated by the ability of a dual inhibitor to reduce disease burden and prolong survival in mice as well as prevent proliferation and promote activation of proapoptotic pathways in human tumors. These results support combined inhibition of PI3Kγ/δ as therapy for T-ALL.
Assuntos
Antineoplásicos/uso terapêutico , Inibidores de Fosfoinositídeo-3 Quinase , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Isoformas de Proteínas , Purinas/uso terapêutico , Quinazolinonas/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Classe I de Fosfatidilinositol 3-Quinases , Classe Ib de Fosfatidilinositol 3-Quinase/química , Classe Ib de Fosfatidilinositol 3-Quinase/genética , Desenho de Fármacos , Inativação Gênica/efeitos dos fármacos , Humanos , Camundongos , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/química , Fosfatidilinositol 3-Quinases/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Purinas/química , Purinas/farmacologia , Quinazolinonas/química , Quinazolinonas/farmacologiaRESUMO
Early immature T cell acute lymphoblastic leukemias (T-ALLs) account for ~5-10% of pediatric T-ALLs and are associated with poor prognosis. However, the genetic defects that drive the biology of these tumors remain largely unknown. In this study, analysis of microarray gene expression signatures in adult T-ALL demonstrated a high prevalence of early immature leukemias and revealed a close relationship between these tumors and myeloid leukemias. Many adult immature T-ALLs harbored mutations in myeloid-specific oncogenes and tumor suppressors including IDH1, IDH2, DNMT3A, FLT3, and NRAS. Moreover, we identified ETV6 mutations as a novel genetic lesion uniquely present in immature adult T-ALL. Our results demonstrate that early immature adult T-ALL represents a heterogeneous category of leukemias characterized by the presence of overlapping myeloid and T-ALL characteristics, and highlight the potential role of ETV6 mutations in these tumors.