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1.
Blood ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941612

RESUMO

In acute myeloid leukemia (AML), leukemia stem and progenitor cells (LSCs and LPCs) interact with various cell types in the bone marrow (BM) microenvironment, regulating their expansion and differentiation. To study the interaction of CD4+ and CD8+ T-cells in the BM with LSCs and LPCs, we analyzed their transcriptome and predicted cell-cell interactions by unbiased high-throughput correlation network analysis. We found that CD4+ T-cells in the BM of AML patients were activated and skewed towards Th1-polarization whereas IL-9 producing (Th9) CD4+ T-cells were absent. In contrast to normal hematopoietic stem cells (HSCs), LSCs produced IL-9 and the correlation modelling predicted IL9 in LSCs as a main hub-gene that activates CD4+ T-cells in AML. Functional validation revealed that IL-9R signaling in CD4+ T-cells leads to activation of the JAK-STAT pathway that induces the upregulation of KMT2A, KMT2C genes resulting in methylation on histone H3 at lysine 4 (H3K4) to promote genome accessibility and transcriptional activation. This induced Th1-skewing, proliferation and effector cytokine secretion, including interferon (IFN)-É£ and tumor necrosis factor (TNF)-α. IFN-É£ and to a lesser extend TNF-α produced by activated CD4+ T-cells, induced the expansion of LSCs. In accordance with our findings, high IL9 expression in LSCs and high IL9R, TNF and IFNG expression in BM-infiltrating CD4+ T-cells correlated with worse overall survival in AML. Thus, IL-9 secreted by AML LSCs shapes a Th1-skewed immune environment that promotes their expansion by secreting IFN-É£ and TNF-α.

2.
Blood ; 130(3): 297-309, 2017 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-28495792

RESUMO

The interaction of the tumor necrosis factor receptor (TNFR) CD27 with its ligand CD70 is an emerging target to treat cancer. CD27 signaling provides costimulatory signals to cytotoxic T cells but also increases the frequency of regulatory T cells. Similar to other TNFR ligands, CD70 has been shown to initiate intracellular signaling pathways (CD70 reverse signaling). CD27 is expressed on a majority of B-cell non-Hodgkin lymphoma, but its role in the immune control of lymphoma and leukemia is unknown. We therefore generated a cytoplasmic deletion mutant of CD27 (CD27-trunc) to study the role of CD70 reverse signaling in the immunosurveillance of B-cell malignancies in vivo. Expression of CD27-trunc on malignant cells increased the number of tumor-infiltrating interferon γ-producing natural killer (NK) cells. In contrast, the antitumoral T-cell response remained largely unchanged. CD70 reverse signaling in NK cells was mediated via the AKT signaling pathway and increased NK cell survival and effector function. The improved immune control by activated NK cells prolonged survival of CD27-trunc-expressing lymphoma-bearing mice. Finally, CD70 reverse signaling enhanced survival and effector function of human NK cells in a B-cell acute lymphoblastic leukemia xenotransplants model. Therefore, CD70 reverse signaling in NK cells contributes to the immune control of CD27-expressing B-cell lymphoma and leukemia.


Assuntos
Linfócitos B/imunologia , Ligante CD27/imunologia , Citotoxicidade Imunológica , Células Matadoras Naturais/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Animais , Linfócitos B/patologia , Ligante CD27/genética , Expressão Gênica , Humanos , Vigilância Imunológica , Interferon gama/genética , Interferon gama/imunologia , Células Matadoras Naturais/patologia , Ligantes , Ativação Linfocitária , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/patologia , Camundongos , Camundongos Knockout , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/imunologia , Transdução de Sinais , Análise de Sobrevida , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/patologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia , Transplante Heterólogo , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/deficiência , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética
3.
Haematologica ; 104(4): 766-777, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30381301

RESUMO

Diffuse large B-cell lymphoma is the most common malignant lymphoma in adults. By gene-expression profiling, this lymphoma is divided in three cell-of-origin subtypes with distinct molecular and clinical features. Most lymphomas arise sporadically, yet familial clustering is known, suggesting a genetic contribution to disease risk. Familial lymphoma cases are a valuable tool to investigate risk genes. We studied a Swiss/Japanese family with 2 sisters affected by a primary mediastinal B-cell lymphoma and a non-germinal center diffuse large B-cell lymphoma not otherwise specified, respectively. The somatic landscape of both lymphomas was marked by alterations affecting multiple components of the JAK-STAT pathway. Consequently, this pathway was constitutively activated as evidenced by high pJAK2 as well as increased nuclear pSTAT3 and pSTAT6 in malignant cells. Potential lymphoma risk variants were identified by whole exome sequencing of the germline DNA derived from siblings and unaffected family members. This analysis revealed a pathogenic variant in TIRAP, an upstream regulator of NF-κB, in both affected siblings and their mother. We observed increased B-cell proliferation in family members harboring the TIRAP p.R81C variant. B-cell proliferation correlated with TIRAP and NF-κB target gene expression, suggesting enhanced NF-κB pathway activity in TIRAP p.R81C individuals. TIRAP knockdown reduced B-cell survival and NF-κB target gene expression, particularly in individuals with TIRAP p.R81C. Functional studies revealed significantly increased NF-κB activity and resistance to stress-induced cell-death by TIRAP p.R81C. The identification of an inherited TIRAP variant provides evidence for a novel link between genetic alterations affecting the NF-κB pathway and lymphomagenesis.


Assuntos
Linfócitos B , Proliferação de Células/genética , Linfoma Difuso de Grandes Células B , Neoplasias do Mediastino , Glicoproteínas de Membrana , Mutação de Sentido Incorreto , Receptores de Interleucina-1 , Irmãos , Transdução de Sinais/genética , Adulto , Linfócitos B/metabolismo , Linfócitos B/patologia , Feminino , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Masculino , Neoplasias do Mediastino/genética , Neoplasias do Mediastino/metabolismo , Neoplasias do Mediastino/patologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT6/genética , Fator de Transcrição STAT6/metabolismo , Sequenciamento do Exoma
4.
Blood ; 124(9): 1393-403, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-24990886

RESUMO

Systemic bacterial infection induces a hematopoietic response program termed "emergency granulopoiesis" that is characterized by increased de novo bone marrow (BM) neutrophil production. How loss of local immune control and bacterial dissemination is sensed and subsequently translated into the switch from steady-state to emergency granulopoiesis is, however, unknown. Using tissue-specific myeloid differentiation primary response gene 88 (Myd88)-deficient mice and in vivo lipopolysaccharide (LPS) administration to model severe bacterial infection, we here show that endothelial cells (ECs) but not hematopoietic cells, hepatocytes, pericytes, or BM stromal cells, are essential cells for this process. Indeed, ECs from multiple tissues including BM express high levels of Tlr4 and Myd88 and are the primary source of granulocyte colony-stimulating factor (G-CSF), the key granulopoietic cytokine, after LPS challenge or infection with Escherichia coli. EC-intrinsic MYD88 signaling and subsequent G-CSF production by ECs is required for myeloid progenitor lineage skewing toward granulocyte-macrophage progenitors, increased colony-forming unit granulocyte activity in BM, and accelerated BM neutrophil generation after LPS stimulation. Thus, ECs catalyze the detection of systemic infection into demand-adapted granulopoiesis.


Assuntos
Células Endoteliais/fisiologia , Fator Estimulador de Colônias de Granulócitos/fisiologia , Granulócitos/patologia , Granulócitos/fisiologia , Interações Hospedeiro-Patógeno/fisiologia , Mielopoese/fisiologia , Animais , Ensaio de Unidades Formadoras de Colônias , Infecções por Escherichia coli/patologia , Infecções por Escherichia coli/fisiopatologia , Lipopolissacarídeos/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Modelos Biológicos , Fator 88 de Diferenciação Mieloide/deficiência , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/fisiologia , Neutrófilos/patologia , Neutrófilos/fisiologia , Transdução de Sinais , Receptor 4 Toll-Like/deficiência , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/fisiologia , Molécula 1 de Adesão de Célula Vascular/fisiologia
5.
Front Immunol ; 14: 1243997, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37744361

RESUMO

Multiple myeloma (MM) is a hematologic malignancy characterized by the proliferation of clonal plasma cells in the bone marrow (BM). It is known that early genetic mutations in post-germinal center B/plasma cells are the cause of myelomagenesis. The acquisition of additional chromosomal abnormalities and distinct mutations further promote the outgrowth of malignant plasma cell populations that are resistant to conventional treatments, finally resulting in relapsed and therapy-refractory terminal stages of MM. In addition, myeloma cells are supported by autocrine signaling pathways and the tumor microenvironment (TME), which consists of diverse cell types such as stromal cells, immune cells, and components of the extracellular matrix. The TME provides essential signals and stimuli that induce proliferation and/or prevent apoptosis. In particular, the molecular pathways by which MM cells interact with the TME are crucial for the development of MM. To generate successful therapies and prevent MM recurrence, a thorough understanding of the molecular mechanisms that drive MM progression and therapy resistance is essential. In this review, we summarize key mechanisms that promote myelomagenesis and drive the clonal expansion in the course of MM progression such as autocrine signaling cascades, as well as direct and indirect interactions between the TME and malignant plasma cells. In addition, we highlight drug-resistance mechanisms and emerging therapies that are currently tested in clinical trials to overcome therapy-refractory MM stages.


Assuntos
Neoplasias Hematológicas , Mieloma Múltiplo , Humanos , Mieloma Múltiplo/terapia , Mieloma Múltiplo/tratamento farmacológico , Plasmócitos/metabolismo , Medula Óssea/metabolismo , Evolução Clonal/genética , Microambiente Tumoral/genética
6.
Sci Signal ; 16(800): eadd7705, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37643244

RESUMO

Cell stemness is characterized by quiescence, pluripotency, and long-term self-renewal capacity. Therapy-resistant leukemic stem cells (LSCs) are the primary cause of relapse in patients with chronic and acute myeloid leukemia (CML and AML). However, the same signaling pathways frequently support stemness in both LSCs and normal hematopoietic stem cells (HSCs), making LSCs difficult to therapeutically target. In cell lines and patient samples, we found that interleukin-33 (IL-33) signaling promoted stemness only in leukemia cells in a subtype-specific manner. The IL-33 receptor ST2 was abundant on the surfaces of CD34+ BCR/ABL1 CML and CD34+ AML cells harboring AML1/ETO and DEK/NUP214 translocations or deletion of chromosome 9q [del(9q)]. The cell surface abundance of ST2, which was lower or absent on other leukemia subtypes and HSCs, correlated with stemness, activated Wnt signaling, and repressed Notch signaling. IL-33-ST2 signaling promoted the maintenance and expansion of AML1/ETO-, DEK/NUP214-, and BCR/ABL1-positive LSCs in culture and in mice by activating Wnt, MAPK, and NF-κB signaling. Wnt signaling and its inhibition of the Notch pathway up-regulated the expression of the gene encoding ST2, thus forming a cell-autonomous loop. IL-33-ST2 signaling promoted the resistance of CML cells to the tyrosine kinase inhibitor (TKI) nilotinib and of AML cells to standard chemotherapy. Thus, inhibiting IL-33-ST2 signaling may target LSCs to overcome resistance to chemotherapy or TKIs in these subtypes of leukemia.


Assuntos
Interleucina-33 , Leucemia Mieloide , Animais , Camundongos , Proteína 1 Semelhante a Receptor de Interleucina-1 , Interleucina-33/genética , NF-kappa B , Via de Sinalização Wnt
7.
Hum Mol Genet ; 19(15): 2936-46, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20466735

RESUMO

The present study investigated promoter hypermethylation of TP53 regulatory pathways providing a potential link between epigenetic changes and mitochondrial DNA (mtDNA) alterations in breast cancer patients lacking a TP53 mutation. The possibility of using the cancer-specific alterations in serum samples as a blood-based test was also explored. Triple-matched samples (cancerous tissues, matched adjacent normal tissues and serum samples) from breast cancer patients were screened for TP53 mutations, and the promoter methylation profile of P14(ARF), MDM2, TP53 and PTEN genes was analyzed as well as mtDNA alterations, including D-loop mutations and mtDNA content. In the studied cohort, no mutation was found in TP53 (DNA-binding domain). Comparison of P14(ARF) and PTEN methylation patterns showed significant hypermethylation levels in tumor tissues (P < 0.05 and <0.01, respectively) whereas the TP53 tumor suppressor gene was not hypermethylated (P < 0.511). The proportion of PTEN methylation was significantly higher in serum than in the normal tissues and it has a significant correlation to tumor tissues (P < 0.05). mtDNA analysis revealed 36.36% somatic and 90.91% germline mutations in the D-loop region and also significant mtDNA depletion in tumor tissues (P < 0.01). In addition, the mtDNA content in matched serum was significantly lower than in the normal tissues (P < 0.05). These data can provide an insight into the management of a therapeutic approach based on the reversal of epigenetic silencing of the crucial genes involved in regulatory pathways of the tumor suppressor TP53. Additionally, release of significant aberrant methylated PTEN in matched serum samples might represent a promising biomarker for breast cancer.


Assuntos
Neoplasias da Mama/genética , Metilação de DNA/genética , DNA Mitocondrial/genética , Transdução de Sinais/genética , Proteína Supressora de Tumor p53/genética , Neoplasias da Mama/patologia , Ilhas de CpG/genética , Análise Mutacional de DNA , Feminino , Genes Neoplásicos/genética , Ensaios de Triagem em Larga Escala , Humanos , Pessoa de Meia-Idade , Mitocôndrias/genética , Mutação/genética , Conformação de Ácido Nucleico , PTEN Fosfo-Hidrolase/genética , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Proteína Supressora de Tumor p14ARF/genética
8.
BMC Cancer ; 12: 244, 2012 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-22695536

RESUMO

BACKGROUND: Invasion and metastasis are two important hallmarks of malignant tumors caused by complex genetic and epigenetic alterations. The present study investigated the contribution of aberrant methylation profiles of cancer related genes, APC, BIN1, BMP6, BRCA1, CST6, ESR-b, GSTP1, P14 (ARF), P16 (CDKN2A), P21 (CDKN1A), PTEN, and TIMP3, in the matched axillary lymph node metastasis in comparison to the primary tumor tissue and the adjacent normal tissue from the same breast cancer patients to identify the potential of candidate genes methylation as metastatic markers. METHODS: The quantitative methylation analysis was performed using the SEQUENOM's EpiTYPER™ assay which relies on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). RESULTS: The quantitative DNA methylation analysis of the candidate genes showed higher methylation proportion in the primary tumor tissue than that of the matched normal tissue and the differences were significant for the APC, BIN1, BMP6, BRCA1, CST6, ESR-b, P16, PTEN and TIMP3 promoter regions (P<0.05). Among those candidate methylated genes, APC, BMP6, BRCA1 and P16 displayed higher methylation proportion in the matched lymph node metastasis than that found in the normal tissue (P<0.05). The pathway analysis revealed that BMP6, BRCA1 and P16 have a role in prevention of neoplasm metastasis. CONCLUSIONS: The results of the present study showed methylation heterogeneity between primary tumors and metastatic lesion. The contribution of aberrant methylation alterations of BMP6, BRCA1 and P16 genes in lymph node metastasis might provide a further clue to establish useful biomarkers for screening metastasis.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Metilação de DNA , Linfonodos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Ilhas de CpG , Feminino , Perfilação da Expressão Gênica , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Regiões Promotoras Genéticas , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
9.
Front Oncol ; 12: 941437, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35847862

RESUMO

Multiple myeloma (MM) is the most common malignant monoclonal disease of plasma cells. Aside from classical chemotherapy and glucocorticoids, proteasome inhibitors, immunomodulatory agents and monoclonal antibodies are used in the current treatment scheme of MM. The tumor microenvironment (TME) plays a fundamental role in the development and progression of numerous solid and non-solid cancer entities. In MM, the survival and expansion of malignant plasma cell clones heavily depends on various direct and indirect signaling pathways provided by the surrounding bone marrow (BM) niche. In a number of MM patients, single plasma cell clones lose their BM dependency and are capable to engraft at distant body sites or organs. The resulting condition is defined as an extramedullary myeloma (EMM). EMMs are highly aggressive disease stages linked to a dismal prognosis. Emerging literature demonstrates that the dynamic interactions between the TME and malignant plasma cells affect myeloma dissemination. In this review, we aim to summarize how the cellular and non-cellular BM compartments can promote plasma cells to exit their BM niche and metastasize to distant intra-or extramedullary locations. In addition, we list selected therapy concepts that directly target the TME with the potential to prevent myeloma spread.

10.
Leukemia ; 36(11): 2634-2646, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36163264

RESUMO

Disease progression and relapse of chronic myeloid leukemia (CML) are caused by therapy resistant leukemia stem cells (LSCs), and cure relies on their eradication. The microenvironment in the bone marrow (BM) is known to contribute to LSC maintenance and resistance. Although leukemic infiltration of the spleen is a hallmark of CML, it is unknown whether spleen cells form a niche that maintains LSCs. Here, we demonstrate that LSCs preferentially accumulate in the spleen and contribute to disease progression. Spleen LSCs were located in the red pulp close to red pulp macrophages (RPM) in CML patients and in a murine CML model. Pharmacologic and genetic depletion of RPM reduced LSCs and decreased their cell cycling activity in the spleen. Gene expression analysis revealed enriched stemness and decreased myeloid lineage differentiation in spleen leukemic stem and progenitor cells (LSPCs). These results demonstrate that splenic RPM form a niche that maintains CML LSCs in a quiescent state, resulting in disease progression and resistance to therapy.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Leucemia Mieloide , Humanos , Camundongos , Animais , Baço , Células-Tronco Neoplásicas/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mieloide/genética , Macrófagos/metabolismo , Progressão da Doença , Microambiente Tumoral
11.
Cell Death Dis ; 13(5): 448, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35538058

RESUMO

The family of hexokinases (HKs) catalyzes the first step of glycolysis, the ATP-dependent phosphorylation of glucose to glucose-6-phosphate. While HK1 and HK2 are ubiquitously expressed, the less well-studied HK3 is primarily expressed in hematopoietic cells and tissues and is highly upregulated during terminal differentiation of some acute myeloid leukemia (AML) cell line models. Here we show that expression of HK3 is predominantly originating from myeloid cells and that the upregulation of this glycolytic enzyme is not restricted to differentiation of leukemic cells but also occurs during ex vivo myeloid differentiation of healthy CD34+ hematopoietic stem and progenitor cells. Within the hematopoietic system, we show that HK3 is predominantly expressed in cells of myeloid origin. CRISPR/Cas9 mediated gene disruption revealed that loss of HK3 has no effect on glycolytic activity in AML cell lines while knocking out HK2 significantly reduced basal glycolysis and glycolytic capacity. Instead, loss of HK3 but not HK2 led to increased sensitivity to ATRA-induced cell death in AML cell lines. We found that HK3 knockout (HK3-null) AML cells showed an accumulation of reactive oxygen species (ROS) as well as DNA damage during ATRA-induced differentiation. RNA sequencing analysis confirmed pathway enrichment for programmed cell death, oxidative stress, and DNA damage response in HK3-null AML cells. These signatures were confirmed in ATAC sequencing, showing that loss of HK3 leads to changes in chromatin configuration and increases the accessibility of genes involved in apoptosis and stress response. Through isoform-specific pulldowns, we furthermore identified a direct interaction between HK3 and the proapoptotic BCL-2 family member BIM, which has previously been shown to shorten myeloid life span. Our findings provide evidence that HK3 is dispensable for glycolytic activity in AML cells while promoting cell survival, possibly through direct interaction with the BH3-only protein BIM during ATRA-induced neutrophil differentiation.


Assuntos
Hexoquinase , Leucemia Mieloide Aguda , Sobrevivência Celular/genética , Glicólise/genética , Hexoquinase/genética , Hexoquinase/metabolismo , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Células Mieloides/metabolismo
12.
World J Stem Cells ; 13(6): 542-567, 2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34249227

RESUMO

Aberrant epigenetic alterations play a decisive role in cancer initiation and propagation via the regulation of key tumor suppressor genes and oncogenes or by modulation of essential signaling pathways. Autophagy is a highly regulated mechanism required for the recycling and degradation of surplus and damaged cytoplasmic constituents in a lysosome dependent manner. In cancer, autophagy has a divergent role. For instance, autophagy elicits tumor promoting functions by facilitating metabolic adaption and plasticity in cancer stem cells (CSCs) and cancer cells. Moreover, autophagy exerts pro-survival mechanisms to these cancerous cells by influencing survival, dormancy, immunosurveillance, invasion, metastasis, and resistance to anti-cancer therapies. In addition, recent studies have demonstrated that various tumor suppressor genes and oncogenes involved in autophagy, are tightly regulated via different epigenetic modifications, such as DNA methylation, histone modifications and non-coding RNAs. The impact of epigenetic regulation of autophagy in cancer cells and CSCs is not well-understood. Therefore, uncovering the complex mechanism of epigenetic regulation of autophagy provides an opportunity to improve and discover novel cancer therapeutics. Subsequently, this would aid in improving clinical outcome for cancer patients. In this review, we provide a comprehensive overview of the existing knowledge available on epigenetic regulation of autophagy and its importance in the maintenance and homeostasis of CSCs and cancer cells.

13.
Front Oncol ; 11: 663406, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017684

RESUMO

BACKGROUND: Immune-checkpoint (IC) inhibitors have revolutionized the treatment of multiple solid tumors and defined lymphomas, but they are largely ineffective in acute myeloid leukemia (AML). The reason why especially PD1/PD-L1 blocking agents are not efficacious is not well-understood but it may be due to the contribution of different IC ligand/receptor interactions that determine the function of T cells in AML. METHODS: To analyze the interactions of IC ligands and receptors in AML, we performed a comprehensive transcriptomic analysis of FACS-purified leukemia stem/progenitor cells and paired bone marrow (BM)-infiltrating CD4+ and CD8+ T cells from 30 patients with AML. The gene expression profiles of activating and inhibiting IC ligands and receptors were correlated with the clinical data. Epigenetic mechanisms were studied by inhibiting the histone deacetylase with valproic acid or by gene silencing of PAC1. RESULTS: We observed that IC ligands and receptors were mainly upregulated in leukemia stem cells. The gene expression of activating IC ligands and receptors correlated with improved prognosis and vice versa. In contrast, the majority of IC receptor genes were downregulated in BM-infiltrating CD8+ T cells and partially in CD4+ T cells, due to pathological chromatin remodeling via histone deacetylation. Therefore, treatment with histone deacetylase inhibitor (HDACi) or silencing of PAC1, as a T cell-specific epigenetic modulator, significantly increased the expression of IC receptors and defined effector molecules in CD8+ T cells. CONCLUSIONS: Our results suggest that CD8+ T cells in AML are dysfunctional mainly due to pathological epigenetic silencing of activating IC receptors rather than due to signaling by immune inhibitory IC receptors, which may explain the limited efficacy of antibodies that block immune-inhibitory ICs in AML.

14.
JCI Insight ; 6(23)2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34727093

RESUMO

Leukemia stem cells (LSCs) promote the disease and seem resistant to therapy and immune control. Why LSCs are selectively resistant against elimination by CD8+ cytotoxic T cells (CTLs) is still unknown. In this study, we demonstrate that LSCs in chronic myeloid leukemia (CML) can be recognized and killed by CD8+ CTLs in vitro. However, Tregs, which preferentially localized close to CD8+ CTLs in CML BM, protected LSCs from MHC class I-dependent CD8+ CTL-mediated elimination in vivo. BM Tregs in CML were characterized by the selective expression of tumor necrosis factor receptor 4 (Tnfrsf4). Stimulation of Tnfrsf4 signaling did not deplete Tregs but reduced the capacity of Tregs to protect LSCs from CD8+ CTL-mediated killing. In the BM of newly diagnosed CML patients, TNFRSF4 mRNA levels were significantly increased and correlated with the expression of the Treg-restricted transcription factor FOXP3. Overall, these results identify Tregs as key regulators of immune escape of LSCs and TNFRSF4 as a potential target to reduce the function of Tregs and boost antileukemic immunity in CML.


Assuntos
Imunoterapia/métodos , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Receptores OX40/metabolismo , Linfócitos T Reguladores/imunologia , Evasão Tumoral/imunologia , Animais , Doença Crônica , Feminino , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Camundongos
15.
Cell Rep ; 34(4): 108663, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33503440

RESUMO

Self-renewal is a key characteristic of leukemia stem cells (LSCs) responsible for the development and maintenance of leukemia. In this study, we identify CD93 as an important regulator of self-renewal and proliferation of murine and human LSCs, but not hematopoietic stem cells (HSCs). The intracellular domain of CD93 promotes gene transcription via the transcriptional regulator SCY1-like pseudokinase 1 independently of ligation of the extracellular domain. In a drug library screen, we identify the anti-emetic agent metoclopramide as an efficient blocker of CD93 signaling. Metoclopramide treatment reduces murine and human LSCs in vitro and prolongs survival of chronic myeloid leukemia (CML) mice through downregulation of pathways related to stemness and proliferation in LSCs. Overall, these results identify CD93 signaling as an LSC-specific regulator of self-renewal and proliferation and a targetable pathway to eliminate LSCs in CML.


Assuntos
Antagonistas dos Receptores de Dopamina D2/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Metoclopramida/uso terapêutico , Animais , Antagonistas dos Receptores de Dopamina D2/farmacologia , Humanos , Metoclopramida/farmacologia , Camundongos
16.
Biol Reprod ; 82(4): 745-50, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20075396

RESUMO

Differences in DNA methylation patterns between placenta and blood cells of pregnant women have been suggested as potential biomarkers for noninvasive prenatal diagnostic strategies, including for common obstetrical complications, such as preeclampsia. New findings in epigenetic origins of fetal or placental disorders may improve our ability for optimal management of these conditions. Using a novel high-throughput mass spectrometry on matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass array, we compared the quantitative methylation changes of RASSF1 and SERPINB5 (also known as MASPIN) genes in placenta and plasma samples. We analyzed the methylation status of a total of 3569 CpG dinucleotides on these two genes in 83 different samples: 50 plasma samples (20 from pregnant women and 30 from nonpregnant women) and 33 placenta tissue samples (25 from normal pregnancies and eight from preeclamptic pregnancies). The aim of this study was to assess the utility of epigenetic changes as biomarkers for noninvasive prenatal diagnostic procedures. Using a two-way hierarchical cluster analysis, significantly different methylation levels of the RASSF1 gene were found between placenta (normal and preeclamptic) and plasma samples of pregnant women. Although the SERPINB5 gene was hypomethylated in placenta DNA more than in plasma DNA, it did not demonstrate significant differences between studied groups. The MALDI-TOF mass spectrometry analysis of placenta and plasma DNA methylation patterns may serve as a tool for the study of gender-independent biomarkers in noninvasive prenatal diagnosis.


Assuntos
Metilação de DNA , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Placenta/metabolismo , Plasma/metabolismo , Serpinas/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Proteínas Supressoras de Tumor/genética , Sequência de Bases , Análise por Conglomerados , Epigênese Genética/fisiologia , Feminino , Idade Gestacional , Humanos , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/metabolismo , Gravidez , Diagnóstico Pré-Natal/métodos , Serpinas/sangue , Serpinas/metabolismo , Proteínas Supressoras de Tumor/análise , Proteínas Supressoras de Tumor/sangue , Proteínas Supressoras de Tumor/metabolismo
17.
Mod Pathol ; 23(5): 763-72, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20081803

RESUMO

Unregulated cell growth, a major hallmark of cancer, is coupled with telomere shortening. Measurement of telomere length could provide important information on cell replication and proliferation state in cancer tissues. Telomere shortening and its potential correlation with downregulation of cell-cycle regulatory elements were studied by the examination of relative telomere length and methylation status of the TP53, P21 and P16 promoters in tissues from breast cancer patients. Telomere length was measured in 104 samples (52 tumors and paired adjacent normal breast tissues) by quantitative PCR. Methylation profile of selected genes was analyzed in all samples using a matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Our results demonstrated a significant shortening of tumor telomere regions compared with paired adjacent normal tissues (P<0.001). Similarly, telomere lengths were significantly shorter in advanced stage cases and in those with higher histological grades (P<0.05). Telomere shortening in cancer tissues was correlated with a different level of hypermethylation in the TP53, P21 and P16 promoters (r=-0.33, P=0.001; r=-0.70, P<0.0001 and r=-0.71, P<0.0001, respectively). The results suggested that inactivation of p16/Rb and/or p53/p21 pathways by hypermethylation may be linked to critical telomere shortening, leading to genome instability and ultimately to malignant transformation. Thus, telomere shortening and promoter hypermethylation of related genes both might serve as breast cancer biomarkers.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , Metilação de DNA/genética , Regiões Promotoras Genéticas/genética , Telômero/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/metabolismo , Carcinoma Lobular/patologia , Ciclo Celular/genética , Inibidor p16 de Quinase Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Espectrometria de Massas , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Telomerase/genética , Telomerase/metabolismo , Telômero/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
18.
Front Oncol ; 10: 569017, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240813

RESUMO

The immune system is able to recognize and eliminate tumor cells. Some tumors, including colorectal cancer (CRC), induce immune tolerance via different mechanisms of "immunoediting" and "immune evasion" and can thus escape immune surveillance. The impact of immunotherapy on cancer has been investigated for many years, but so far, the application was limited to few cancer types. Immuno-oncological therapeutic strategies against metastatic colorectal cancer (mCRC), the adaptive immune system activating approaches, offer a high potential for adaptation to the great heterogeneity of CRC. Moreover, novel treatment approaches are currently being tested that might specifically target the disease initiating and maintaining population of colorectal cancer stem cells (CSCs). In this review, we aim to summarize the current state of immune-oncology and tumor immunotherapy of patients with mCRC and discuss different therapeutic modalities that focus on the activation of tumor-specific T-cells and their perspectives such as tumor vaccination, checkpoint inhibition, and adoptive T-cell transfer or on the eradication of colorectal CSCs.

19.
World J Stem Cells ; 12(5): 303-322, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32547680

RESUMO

Autophagy is a highly regulated catabolic process in which superfluous, damaged organelles and other cytoplasmic constituents are delivered to the lysosome for clearance and the generation of macromolecule substrates during basal or stressed conditions. Autophagy is a bimodal process with a context dependent role in the initiation and the development of cancers. For instance, autophagy provides an adaptive response to cancer stem cells to survive metabolic stresses, by influencing disease propagation via modulation of essential signaling pathways or by promoting resistance to chemotherapeutics. Autophagy has been implicated in a cross talk with apoptosis. Understanding the complex interactions provides an opportunity to improve cancer therapy and the clinical outcome for the cancer patients. In this review, we provide a comprehensive view on the current knowledge on autophagy and its role in cancer cells with a particular focus on cancer stem cell homeostasis.

20.
Int J Prev Med ; 11: 117, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33088445

RESUMO

BACKGROUND: Various blood diseases are caused by mutations in the FANCA, FANCC, and ITGA2B genes. Exome sequencing is a suitable method for identifying single-gene disease and genetic heterogeneity complaints. METHODS: Among families who were referred to Narges Genetic and PND Laboratory in 2015-2017, five families with a history of blood diseases were analyzed using the whole exome sequencing (WES) method. RESULTS: We detected two novel mutations (c.190-2A>G and c.2840C>G) in the FANCA gene, c. 1429dupA mutation in the FANCC gene, and c.1392A>G mutation in the ITGA2B gene. The prediction of variant pathogenicity has been done using bioinformatics tools such as Mutation taster PhD-SNP and polyphen2 and were confirmed by Sanger sequencing. CONCLUSIONS: WES could be as a precise tool for identifying the pathologic variants in affected patient and heterozygous carriers among families. This highly successful technique will remain at the forefront of platelet and blood genomic research.

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