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1.
Haematologica ; 108(1): 219-233, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36073514

RESUMO

Long non-coding RNA NEAT1 is the core structural component of the nuclear paraspeckle (PS) organelles and it has been found to be deregulated in multiple myeloma (MM) patients. Experimental evidence indicated that NEAT1 silencing negatively impacts proliferation and viability of MM cells, both in vitro and in vivo, suggesting a role in DNA damage repair (DDR). In order to elucidate the biological and molecular relevance of NEAT1 upregulation in MM disease we exploited the CRISPR/Cas9 synergistic activation mediator genome editing system to engineer the AMO-1 MM cell line and generate two clones that para-physiologically transactivate NEAT1 at different levels. NEAT1 overexpression is associated with oncogenic and prosurvival advantages in MM cells exposed to nutrient starvation or a hypoxic microenvironment, which are stressful conditions often associated with more aggressive disease phases. Furthermore, we highlighted the NEAT1 involvement in virtually all DDR processes through, at least, two different mechanisms. On one side NEAT1 positively regulates the posttranslational stabilization of essential PS proteins, which are involved in almost all DDR systems, thus increasing their availability within cells. On the other hand, NEAT1 plays a crucial role as a major regulator of a molecular axis that includes ATM and the catalytic subunit of DNA-PK kinase proteins, and their direct targets pRPA32 and pCHK2. Overall, we provided novel important insightsthe role of NEAT1 in supporting MM cells adaptation to stressful conditions by improving the maintenance of DNA integrity. Taken together, our results suggest that NEAT1, and probably PS organelles, could represent a potential therapeutic target for MM treatment.


Assuntos
MicroRNAs , Mieloma Múltiplo , RNA Longo não Codificante , Humanos , Linhagem Celular Tumoral , Reparo do DNA , MicroRNAs/genética , Mieloma Múltiplo/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ativação Transcricional , Microambiente Tumoral , Regulação para Cima
2.
Int J Mol Sci ; 23(7)2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35409379

RESUMO

Gene expression is controlled by epigenetic deregulation, a hallmark of cancer. The DNA methylome of canine diffuse large B-cell lymphoma (cDLBCL), the most frequent malignancy of B-lymphocytes in dog, has recently been investigated, suggesting that aberrant hypermethylation of CpG loci is associated with gene silencing. Here, we used a multi-omics approach (DNA methylome, transcriptome and copy number variations) combined with functional in vitro assays, to identify putative tumour suppressor genes subjected to DNA methylation in cDLBCL. Using four cDLBCL primary cell cultures and CLBL-1 cells, we found that CiDEA, MAL and PCDH17, which were significantly suppressed in DLBCL samples, were hypermethylated and also responsive (at the DNA, mRNA and protein level) to pharmacological unmasking with hypomethylating drugs and histone deacetylase inhibitors. The regulatory mechanism underneath the methylation-dependent inhibition of those target genes expression was then investigated through luciferase and in vitro methylation assays. In the most responsive CpG-rich regions, an in silico analysis allowed the prediction of putative transcription factor binding sites influenced by DNA methylation. Interestingly, regulatory elements for AP2, MZF1, NF-kB, PAX5 and SP1 were commonly identified in all three genes. This study provides a foundation for characterisation and experimental validation of novel epigenetically-dysregulated pathways in cDLBCL.


Assuntos
Variações do Número de Cópias de DNA , Metilação de DNA , Animais , Linhagem Celular Tumoral , Ilhas de CpG , Cães , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Genes Supressores de Tumor
3.
Blood ; 133(2): 156-167, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30455381

RESUMO

Proteasome inhibitors (PI) are extensively used for the therapy of multiple myeloma (MM) and mantle cell lymphoma. However, patients continuously relapse or are intrinsically resistant to this class of drugs. Here, to identify targets that synergize with PI, we carried out a functional screening in MM cell lines using a short hairpin RNA library against cancer driver genes. Isocitrate dehydrogenase 2 (IDH2) was identified as a top candidate, showing a synthetic lethal activity with the PI carfilzomib (CFZ). Combinations of US Food and Drug Administration-approved PI with a pharmacological IDH2 inhibitor (AGI-6780) triggered synergistic cytotoxicity in MM, mantle cell lymphoma, and Burkitt lymphoma cell lines. CFZ/AGI-6780 treatment increased death of primary CD138+ cells from MM patients and exhibited a favorable cytotoxicity profile toward peripheral blood mononuclear cells and bone marrow-derived stromal cells. Mechanistically, the CFZ/AGI-6780 combination significantly decreased tricarboxylic acid cycle activity and adenosine triphosphate levels as a consequence of enhanced IDH2 enzymatic inhibition. Specifically, CFZ treatment reduced the expression of nicotinamide phosphoribosyltransferase (NAMPT), thus limiting IDH2 activation through the NAD+-dependent deacetylase SIRT3. Consistently, combination of CFZ with either NAMPT or SIRT3 inhibitors impaired IDH2 activity and increased MM cell death. Finally, inducible IDH2 knockdown enhanced the therapeutic efficacy of CFZ in a subcutaneous xenograft model of MM, resulting in inhibition of tumor progression and extended survival. Taken together, these findings indicate that NAMPT/SIRT3/IDH2 pathway inhibition enhances the therapeutic efficacy of PI, thus providing compelling evidence for treatments with lower and less toxic doses and broadening the application of PI to other malignancies.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias Hematológicas/tratamento farmacológico , Isocitrato Desidrogenase/antagonistas & inibidores , Oligopeptídeos/farmacologia , Inibidores de Proteassoma/farmacologia , Animais , Apoptose , Proliferação de Células , Citocinas/antagonistas & inibidores , Citocinas/genética , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patologia , Humanos , Isocitrato Desidrogenase/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/genética , RNA Interferente Pequeno/genética , Sirtuína 3/antagonistas & inibidores , Sirtuína 3/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Am J Hematol ; 94(6): 628-634, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30829413

RESUMO

The histological diagnosis of peripheral T-cell lymphoma (PTCL) can represent a challenge, particularly in the case of closely related entities such as angioimmunoblastic T-lymphoma (AITL), PTCL-not otherwise specified (PTCL-NOS), and ALK-negative anaplastic large-cell lymphoma (ALCL). Although gene expression profiling and next generations sequencing have been proven to define specific features recurrently associated with distinct entities, genomic-based stratifications have not yet led to definitive diagnostic criteria and/or entered into the routine clinical practice. Herein, to improve the current molecular classification between AITL and PTCL-NOS, we analyzed the transcriptional profiles from 503 PTCLs stratified according to their molecular configuration and integrated them with genomic data of recurrently mutated genes (RHOA G17V , TET2, IDH2 R172 , and DNMT3A) in 53 cases (39 AITLs and 14 PTCL-NOSs) included in the series. Our analysis unraveled that the mutational status of RHOA G17V , TET2, and DNMT3A poorly correlated, individually, with peculiar transcriptional fingerprints. Conversely, in IDH2 R172 samples a strong transcriptional signature was identified that could act as a surrogate for mutational status. The integrated analysis of clinical, mutational, and molecular data led to a simplified 19-gene signature that retains high accuracy in differentiating the main nodal PTCL entities. The expression levels of those genes were confirmed in an independent cohort profiled by RNA-sequencing.


Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Linfoma de Células T Periférico , Mutação , Proteínas de Neoplasias , Transcrição Gênica , Feminino , Humanos , Linfoma de Células T Periférico/genética , Linfoma de Células T Periférico/metabolismo , Masculino , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética
5.
Blood ; 127(2): 221-32, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26463425

RESUMO

Anaplastic large-cell lymphoma (ALCL) is a clinical and biological heterogeneous disease that includes systemic anaplastic lymphoma kinase (ALK)-positive and ALK-negative entities. To discover biomarkers and/or genes involved in ALK-negative ALCL pathogenesis, we applied the cancer outlier profile analysis algorithm to a gene expression profiling data set including 249 cases of T-cell non-Hodgkin lymphoma and normal T cells. Ectopic coexpression of ERBB4 and COL29A1 genes was detected in 24% of ALK-negative ALCL patients. RNA sequencing and 5' RNA ligase-mediated rapid amplification of complementary DNA ends identified 2 novel ERBB4-truncated transcripts displaying intronic transcription start sites. By luciferase assays, we defined that the expression of ERBB4-aberrant transcripts is promoted by endogenous intronic long terminal repeats. ERBB4 expression was confirmed at the protein level by western blot analysis and immunohistochemistry. Lastly, we demonstrated that ERBB4-truncated forms show oncogenic potentials and that ERBB4 pharmacologic inhibition partially controls ALCL cell growth and disease progression in an ERBB4-positive patient-derived tumorgraft model. In conclusion, we identified a new subclass of ALK-negative ALCL characterized by aberrant expression of ERBB4-truncated transcripts carrying intronic 5' untranslated regions.


Assuntos
Linfoma Anaplásico de Células Grandes/genética , Receptores Proteína Tirosina Quinases/genética , Receptor ErbB-4/genética , Regiões 5' não Traduzidas , Quinase do Linfoma Anaplásico , Animais , Códon sem Sentido , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Linfoma Anaplásico de Células Grandes/classificação , Linfoma Anaplásico de Células Grandes/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Camundongos Transgênicos , Dados de Sequência Molecular , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Células NIH 3T3 , RNA Mensageiro/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptor ErbB-4/metabolismo
6.
Blood ; 122(13): 2233-41, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-23926301

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is the most common form of human lymphoma. DLBCL is a heterogeneous disease characterized by different genetic lesions. We herein report the functional characterization of a recurrent gain mapping on chromosome 11q24.3, found in 23% of 166 DLBCL cases analyzed. The transcription factors ETS1 and FLI1, located within the 11q24.3 region, had significantly higher expression in clinical samples carrying the gain. Functional studies on cell lines showed that ETS1 and FLI1 cooperate in sustaining DLBCL proliferation and viability and regulate genes involved in germinal center differentiation. Taken together, these data identify the 11q24.3 gain as a recurrent lesion in DLBCL leading to ETS1 and FLI1 deregulated expression, which can contribute to the pathogenesis of this disease.


Assuntos
Cromossomos Humanos Par 11/genética , Linfoma Difuso de Grandes Células B/genética , Proteína Proto-Oncogênica c-ets-1/genética , Proteína Proto-Oncogênica c-fli-1/genética , Western Blotting , Imunoprecipitação da Cromatina , Eletroporação , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Análise de Sequência com Séries de Oligonucleotídeos , Proteína Proto-Oncogênica c-ets-1/biossíntese , Proteína Proto-Oncogênica c-fli-1/biossíntese , Reação em Cadeia da Polimerase em Tempo Real , Transcriptoma , Transfecção
7.
Blood ; 122(15): 2683-93, 2013 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-24004669

RESUMO

Anaplastic large cell lymphoma (ALCL) is a mature T-cell lymphoma that can present as a systemic or primary cutaneous disease. Systemic ALCL represents 2% to 5% of adult lymphoma but up to 30% of all pediatric cases. Two subtypes of systemic ALCL are currently recognized on the basis of the presence of a translocation involving the anaplastic lymphoma kinase ALK gene. Despite considerable progress, several questions remain open regarding the pathogenesis of both ALCL subtypes. To investigate the molecular pathogenesis and to assess the relationship between the ALK(+) and ALK(-) ALCL subtypes, we performed a genome-wide DNA profiling using high-density, single nucleotide polymorphism arrays on a series of 64 cases and 7 cell lines. The commonest lesions were losses at 17p13 and at 6q21, encompassing the TP53 and PRDM1 genes, respectively. The latter gene, coding for BLIMP1, was inactivated by multiple mechanisms, more frequently, but not exclusively, in ALK(-)ALCL. In vitro and in vivo experiments showed that that PRDM1 is a tumor suppressor gene in ALCL models, likely acting as an antiapoptotic agent. Losses of TP53 and/or PRDM1 were present in 52% of ALK(-)ALCL, and in 29% of all ALCL cases with a clinical implication.


Assuntos
Regulação Neoplásica da Expressão Gênica/genética , Linfoma Anaplásico de Células Grandes/genética , Linfoma de Células T/genética , Proteínas Repressoras/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Pessoa de Meia-Idade , Transplante de Neoplasias , Fator 1 de Ligação ao Domínio I Regulador Positivo , Receptores Proteína Tirosina Quinases/genética , Proteína Supressora de Tumor p53/genética , Adulto Jovem
8.
Blood ; 122(12): 2083-92, 2013 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-23801630

RESUMO

Anaplastic large-cell lymphomas (ALCLs) encompass at least 2 systemic diseases distinguished by the presence or absence of anaplastic lymphoma kinase (ALK) expression. We performed genome-wide microRNA (miRNA) profiling on 33 ALK-positive (ALK[+]) ALCLs, 25 ALK-negative (ALK[-]) ALCLs, 9 angioimmunoblastic T-cell lymphomas, 11 peripheral T-cell lymphomas not otherwise specified (PTCLNOS), and normal T cells, and demonstrated that ALCLs express many of the miRNAs that are highly expressed in normal T cells with the prominent exception of miR-146a. Unsupervised hierarchical clustering demonstrated distinct clustering of ALCL, PTCL-NOS, and the AITL subtype of PTCL. Cases of ALK(+) ALCL and ALK(-) ALCL were interspersed in unsupervised analysis, suggesting a close relationship at the molecular level. We identified an miRNA signature of 7 miRNAs (5 upregulated: miR-512-3p, miR-886-5p, miR-886-3p, miR-708, miR-135b; 2 downregulated: miR-146a, miR-155) significantly associated with ALK(+) ALCL cases. In addition, we derived an 11-miRNA signature (4 upregulated: miR-210, miR-197, miR-191, miR-512-3p; 7 downregulated: miR-451, miR-146a, miR-22, miR-455-3p, miR-455-5p, miR-143, miR-494) that differentiates ALK(-) ALCL from other PTCLs. Our in vitro studies identified a set of 32 miRNAs associated with ALK expression. Of these, the miR-17∼92 cluster and its paralogues were also highly expressed in ALK(+) ALCL and may represent important downstream effectors of the ALK oncogenic pathway.


Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Linfoma Anaplásico de Células Grandes/genética , MicroRNAs/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico , Antígenos de Superfície/metabolismo , Linhagem Celular Tumoral , Criança , Pré-Escolar , Análise por Conglomerados , Feminino , Expressão Gênica , Ordem dos Genes , Humanos , Imunofenotipagem , Linfoma Anaplásico de Células Grandes/metabolismo , Linfoma Anaplásico de Células Grandes/patologia , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Especificidade de Órgãos/genética , Interferência de RNA , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Linfócitos T/metabolismo , Adulto Jovem
9.
Stem Cells ; 32(3): 754-69, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24123662

RESUMO

Signals downstream of Akt can either favor or oppose stem cell (SC) maintenance, but how this dual role can be achieved is still undefined. Using human limbal keratinocyte stem cells (LKSCs), a SC type used in transplantation therapies for corneal regeneration, we show that Akt signaling is prominent in SC populations both in vivo and in vitro, and that Akt1 promotes while Akt2 opposes SC self-renewal. Noteworthy, loss of Akt2 signaling enhances LKSC maintenance ex vivo, whereas Akt1 depletion anticipates SC exhaustion. Mechanistically, the antagonistic functions of Akt1 and Akt2 in SC control are mainly dictated by their differential subcellular distribution, being nuclear Akt2 selectively implicated in FOXO inhibition. Akt2 downregulation favors LKSC maintenance as a result of a gain of FOXO functions, which attenuates the mechanistic target of rapamycin complex one signaling via tuberous sclerosis one gene induction, and promotes growth factor signaling through Akt1. Consistently, Akt2 deficiency also enhances limbal SCs in vivo. Thus, our findings reveal distinct roles for nuclear versus cytosolic Akt signaling in normal epithelial SC control and suggest that the selective Akt2 inhibition may provide novel pharmacological strategies for human LKSC expansion in therapeutic settings and mechanistic research.


Assuntos
Núcleo Celular/enzimologia , Fatores de Transcrição Forkhead/metabolismo , Queratinócitos/citologia , Complexos Multiproteicos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células-Tronco/citologia , Serina-Treonina Quinases TOR/metabolismo , Células 3T3 , Adulto , Animais , Proliferação de Células , Células Clonais , Ativação Enzimática , Proteína Forkhead Box O1 , Proteína Forkhead Box O3 , Humanos , Isoenzimas/metabolismo , Limbo da Córnea/citologia , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Fenótipo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/deficiência , Proteínas Repressoras/metabolismo , Transdução de Sinais , Células-Tronco/enzimologia , Transcrição Gênica
10.
Genes Chromosomes Cancer ; 53(2): 154-67, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24327544

RESUMO

We explored the molecular mechanisms involved in the establishement of CMA-03/06, an IL-6-independent variant of the multiple myeloma cell line CMA-03 previously generated in our Institution. CMA-03/06 cells grow in the absence of IL-6 with a doubling time comparable with that of CMA-03 cells; neither the addition of IL6 (IL-6) to the culture medium nor co-culture with multipotent mesenchymal stromal cells increases the proliferation rate, although they maintain the responsiveness to IL-6 stimulation as demonstrated by STAT1, STAT3, and STAT5 induction. IL-6 independence of CMA-03/06 cells is not apparently due to the development of an autocrine IL-6 loop, nor to the observed moderate constitutive activation of STAT5 and STAT3, since STAT3 silencing does not affect cell viability or proliferation. When compared to the parental cell line, CMA-03/06 cells showed an activated pattern of the NF-κB pathway. This finding is supported by gene expression profiling (GEP) analysis identifying an appreciable fraction of modulated genes (28/308) in the CMA-03/06 subclone reported to be involved in this pathway. Furthermore, although more resistant to apoptotic stimuli compared to the parental cell line, CMA-03/06 cells display a higher sensibility to NF-κB inhibition induced by bortezomib. Finally, GEP analysis suggests an involvement of a number of cytokines, which might contribute to IL-6 independence of CMA-03/06 by stimulating growth and antiapoptotic processes. In conclusion, the parental cell-line CMA-03 and its variant CMA-03/06 represent a suitable model to further investigate molecular mechanisms involved in the IL-6-independent growth of myeloma cells.


Assuntos
Linhagem Celular Tumoral/metabolismo , Interleucina-6/metabolismo , Mieloma Múltiplo/metabolismo , Apoptose , Ácidos Borônicos/farmacologia , Bortezomib , Linhagem Celular Tumoral/patologia , Humanos , Interleucina-6/genética , Interleucina-6/farmacologia , Sistema de Sinalização das MAP Quinases , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Pirazinas/farmacologia , Transdução de Sinais , Transcriptoma
11.
Blood ; 120(6): 1274-81, 2012 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-22740451

RESUMO

Anaplastic large-cell lymphomas (ALCLs) are a group of clinically and biologically heterogeneous diseases including the ALK(+) and ALK(-) systemic forms. Whereas ALK(+) ALCLs are molecularly characterized and can be readily diagnosed, specific immunophenotypic or genetic features to define ALK(-) ALCL are missing, and their distinction from other T-cell non-Hodgkin lymphomas (T-NHLs) remains controversial. In the present study, we undertook a transcriptional profiling meta-analysis of 309 cases, including ALCL and other primary T-NHL samples. Pathway discovery and prediction analyses defined a minimum set of genes capable of recognizing ALK(-) ALCL. Application of quantitative RT-PCR in independent datasets from cryopreserved and formalin-fixed paraffin-embedded samples validated a 3-gene model (TNFRSF8, BATF3, and TMOD1) able to successfully separate ALK(-) ALCL from peripheral T-cell lymphoma not otherwise specified, with overall accuracy near 97%. In conclusion, our data justify the possibility of translating quantitative RT-PCR protocols to routine clinical settings as a new approach to objectively dissect T-NHL and to select more appropriate therapeutic protocols.


Assuntos
Biomarcadores Tumorais/genética , Genes Neoplásicos , Linfoma Anaplásico de Células Grandes/diagnóstico , Linfoma Anaplásico de Células Grandes/genética , Técnicas de Diagnóstico Molecular/métodos , Receptores Proteína Tirosina Quinases/genética , Adulto , Quinase do Linfoma Anaplásico , Biomarcadores Tumorais/isolamento & purificação , Biomarcadores Tumorais/fisiologia , Estudos de Casos e Controles , Diagnóstico Diferencial , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genes Neoplásicos/fisiologia , Humanos , Análise em Microsséries , Modelos Estatísticos , Valor Preditivo dos Testes , Prognóstico , Receptores Proteína Tirosina Quinases/metabolismo
12.
Haematologica ; 99(1): 116-24, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23975180

RESUMO

Systemic anaplastic large cell lymphoma is a category of T-cell non-Hodgkin's lymphoma which can be further subdivided into two distinct entities (ALK(+) and ALK(-)) based on the presence or absence of ALK gene rearrangements. Among several pathways triggered by ALK signaling, constitutive activation of STAT3 is strictly required for ALK-mediated transformation and survival. Here we performed genome-wide microRNA profiling and identified 48 microRNA concordantly modulated by the inducible knock-down of ALK and STAT3. To evaluate the functional role of differentially expressed miRNA, we forced their expression in ALK(+) anaplastic large cell lymphoma cells, and monitored their influence after STAT3 depletion. We found that the expression of the microRNA-17~92 cluster partially rescues STAT3 knock-down by sustaining proliferation and survival of ALK(+) cells. Experiments in a xenograft mouse model indicated that forced expression of microRNA-17~92 interferes with STAT3 knock-down in vivo. High expression levels of the microRNA-17~92 cluster resulted in down-regulation of BIM and TGFßRII proteins, suggesting that their targeting might mediate resistance to STAT3 knock-down in anaplastic large cell lymphoma cells. We speculate that the microRNA-17~92 cluster is involved in lymphomagenesis of STAT3(+) ALCL and that its inhibition might represent an alternative avenue to interfere with ALK signaling in anaplastic large cell lymphomas.


Assuntos
Linfoma Anaplásico de Células Grandes/genética , Linfoma Anaplásico de Células Grandes/metabolismo , MicroRNAs/genética , Família Multigênica , Receptores Proteína Tirosina Quinases/metabolismo , Fator de Transcrição STAT3/metabolismo , Ativação Transcricional , Quinase do Linfoma Anaplásico , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/genética , Análise por Conglomerados , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Linfoma Anaplásico de Células Grandes/mortalidade , Interferência de RNA
13.
Microorganisms ; 11(2)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36838500

RESUMO

The COVID-19 pandemic represented a challenge for health-care systems, and a major bottleneck in SARS-CoV-2 diagnosis was the unavailability of extraction reagents. To overcome this limitation, we performed a comparative analysis to evaluate the performance of an alternative extraction protocol derived from veterinary use adapted to an open robotic platform (Testing method). A total of 73 nasopharyngeal swabs collected for diagnosis of SARS-CoV-2 infection were simultaneously extracted with the Testing protocol and the laboratory Standard of Care in order to assess the performance of the first one. The Cohen's coefficient between both procedures was excellent (K Value = 0.955). Analysis of cycle threshold and linear regression showed a significant correlation between the two methods for each tested genetic target. Although validated for veterinary applications, the Testing method showed excellent performances in RNA extraction, with several advantages: lower sample input volume, the possibility to overcome the lack of deep-well plates and adaptability to robotic liquid handlers.

14.
Cancers (Basel) ; 15(8)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37190128

RESUMO

Proteasome inhibitors (PIs) are extensively used for the therapy of multiple myeloma. However, patients continuously relapse or are intrinsically resistant to this class of drugs. In addition, adverse toxic effects such as peripheral neuropathy and cardiotoxicity could arise. Here, to identify compounds that can increase the efficacy of PIs, we performed a functional screening using a library of small-molecule inhibitors covering key signaling pathways. Among the best synthetic lethal interactions, the euchromatic histone-lysine N-methyltransferase 2 (EHMT2) inhibitor UNC0642 displayed a cooperative effect with carfilzomib (CFZ) in numerous multiple myeloma (MM) cell lines, including drug-resistant models. In MM patients, EHMT2 expression correlated to worse overall and progression-free survival. Moreover, EHMT2 levels were significantly increased in bortezomib-resistant patients. We demonstrated that CFZ/UNC0642 combination exhibited a favorable cytotoxicity profile toward peripheral blood mononuclear cells and bone-marrow-derived stromal cells. To exclude off-target effects, we proved that UNC0642 treatment reduces EHMT2-related molecular markers and that an alternative EHMT2 inhibitor recapitulated the synergistic activity with CFZ. Finally, we showed that the combinatorial treatment significantly perturbs autophagy and the DNA damage repair pathways, suggesting a multi-layered mechanism of action. Overall, the present study demonstrates that EHMT2 inhibition could provide a valuable strategy to enhance PI sensitivity and overcome drug resistance in MM patients.

15.
Exp Hematol Oncol ; 12(1): 71, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563685

RESUMO

BACKGROUND: Multiple myeloma (MM) is an incurable plasma cell malignancy, accounting for approximately 1% of all cancers. Despite recent advances in the treatment of MM, due to the introduction of proteasome inhibitors (PIs) such as bortezomib (BTZ) and carfilzomib (CFZ), relapses and disease progression remain common. Therefore, a major challenge is the development of novel therapeutic approaches to overcome drug resistance, improve patient outcomes, and broaden PIs applicability to other pathologies. METHODS: We performed genetic and drug screens to identify new synthetic lethal partners to PIs, and validated candidates in PI-sensitive and -resistant MM cells. We also tested best synthetic lethal interactions in other B-cell malignancies, such as mantle cell, Burkitt's and diffuse large B-cell lymphomas. We evaluated the toxicity of combination treatments in normal peripheral blood mononuclear cells (PBMCs) and bone marrow stromal cells (BMSCs). We confirmed the combo treatment' synergistic effects ex vivo in primary CD138+ cells from MM patients, and in different MM xenograft models. We exploited RNA-sequencing and Reverse-Phase Protein Arrays (RPPA) to investigate the molecular mechanisms of the synergy. RESULTS: We identified lysine (K)-specific demethylase 1 (LSD1) as a top candidate whose inhibition can synergize with CFZ treatment. LSD1 silencing enhanced CFZ sensitivity in both PI-resistant and -sensitive MM cells, resulting in increased tumor cell death. Several LSD1 inhibitors (SP2509, SP2577, and CC-90011) triggered synergistic cytotoxicity in combination with different PIs in MM and other B-cell neoplasms. CFZ/SP2509 treatment exhibited a favorable cytotoxicity profile toward PBMCs and BMSCs. We confirmed the clinical potential of LSD1-proteasome inhibition in primary CD138+ cells of MM patients, and in MM xenograft models, leading to the inhibition of tumor progression. DNA damage response (DDR) and proliferation machinery were the most affected pathways by CFZ/SP2509 combo treatment, responsible for the anti-tumoral effects. CONCLUSIONS: The present study preclinically demonstrated that LSD1 inhibition could provide a valuable strategy to enhance PI sensitivity and overcome drug resistance in MM patients and that this combination might be exploited for the treatment of other B-cell malignancies, thus extending the therapeutic impact of the project.

16.
Br J Haematol ; 156(3): 354-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22118580

RESUMO

Changes in DNA copy number (CN) and DNA methylation represent important aberrations for lymphomas and other cancers. Here, for the first time, we show that the Illumina Infinium Methylation (IIM) assay, although not originally designed for CN profiling, is able to estimate CN changes. We compared the IIM CN profiles to those obtained with a standard technique in a series of diffuse large B-cell lymphomas: the profiles showed a high degree of consensus. The demonstration of CN profiling as an additional function of the IIM assay may impact the choice of platform for methylation profiling of haematological and solid tumours.


Assuntos
Ilhas de CpG , Metilação de DNA , Dosagem de Genes , Leucemia/genética , Linfoma/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , DNA de Neoplasias/genética , Transplante de Células-Tronco Hematopoéticas , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/cirurgia , Período Pós-Operatório
17.
J Cell Biol ; 176(7): 1035-47, 2007 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-17371830

RESUMO

The serine/threonine protein kinase phosphoinositide-dependent kinase 1 (PDK1) plays a central role in cellular signaling by phosphorylating members of the AGC family of kinases, including PKB/Akt. We now present evidence showing that PDK1 is essential for the motility of vascular endothelial cells (ECs) and that it is involved in the regulation of their chemotaxis. ECs differentiated from mouse embryonic stem cells lacking PDK1 completely lost their ability to migrate in vitro in response to vascular endothelial growth factor-A (VEGF-A). In addition, PDK1(-/-) embryoid bodies exhibit evident developmental and vascular defects that can be attributed to a reduced cell migration. Moreover, the overexpression of PDK1 increased the EC migration induced by VEGF-A. We propose a model of spatial distribution of PDK1 and Akt in which the synthesis of phosphatidylinositol 3,4,5 triphosphate at plasma membrane by activation of phosphoinositide 3-kinase recruits both proteins at the leading edge of the polarized ECs and promotes cell chemotaxis. These findings establish a mechanism for the spatial localization of PDK1 and its substrate Akt to regulate directional migration.


Assuntos
Movimento Celular/fisiologia , Células Endoteliais/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases Dependentes de 3-Fosfoinositídeo , Animais , Membrana Celular/metabolismo , Polaridade Celular/fisiologia , Células Cultivadas , Quimiotaxia/fisiologia , Embrião de Mamíferos/anormalidades , Embrião de Mamíferos/metabolismo , Células Endoteliais/citologia , Humanos , Camundongos , Camundongos Knockout , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia
18.
Cancers (Basel) ; 13(6)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799793

RESUMO

Multiple myeloma is a malignancy of terminally differentiated plasma cells, characterized by an extreme genetic heterogeneity that poses great challenges for its successful treatment. Due to antibody overproduction, MM cells depend on the precise regulation of the protein degradation systems. Despite the success of PIs in MM treatment, resistance and adverse toxic effects such as peripheral neuropathy and cardiotoxicity could arise. To this end, the use of rational combinatorial treatments might allow lowering the dose of inhibitors and therefore, minimize their side-effects. Even though the suppression of different cellular pathways in combination with proteasome inhibitors have shown remarkable anti-myeloma activities in preclinical models, many of these promising combinations often failed in clinical trials. Substantial progress has been made by the simultaneous targeting of proteasome and different aspects of MM-associated immune dysfunctions. Moreover, targeting deranged metabolic hubs could represent a new avenue to identify effective therapeutic combinations with PIs. Finally, epigenetic drugs targeting either DNA methylation, histone modifiers/readers, or chromatin remodelers are showing pleiotropic anti-myeloma effects alone and in combination with PIs. We envisage that the positive outcome of patients will probably depend on the availability of more effective drug combinations and treatment of early MM stages. Therefore, the identification of sensitive targets and aberrant signaling pathways is instrumental for the development of new personalized therapies for MM patients.

19.
Cancers (Basel) ; 13(9)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33924959

RESUMO

Multiple myeloma (MM) is a complex hematological malignancy characterized by abnormal proliferation of malignant plasma cells (PCs) within a permissive bone marrow microenvironment. The pathogenesis of MM is unequivocally linked to the acquisition of genomic instability (GI), which indicates the tendency of tumor cells to accumulate a wide repertoire of genetic alterations. Such alterations can even be detected at the premalignant stages of monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM) and, overall, contribute to the acquisition of the malignant traits underlying disease progression. The molecular basis of GI remains unclear, with replication stress and deregulation of DNA damage repair pathways representing the most documented mechanisms. The discovery that non-coding RNA molecules are deeply dysregulated in MM and can target pivotal components of GI pathways has introduced a further layer of complexity to the GI scenario in this disease. In this review, we will summarize available information on the molecular determinants of GI in MM, focusing on the role of non-coding RNAs as novel means to tackle GI for therapeutic intervention.

20.
Methods Mol Biol ; 2152: 59-75, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32524544

RESUMO

The application of next generation sequencing (NGS) technique has a great impact on complex disease studies. Indeed, genetic heterogeneity, phenotypic variability, and disease rarity are all factors that make the traditional diagnostic approach to genetic disorders, whereby a specific gene is selected for sequencing based on the clinical phenotype, very challenging and obsolete.Exome sequencing, which sequences the protein-coding region of the genome, has been rapidly applied to variant discovery in research settings. Recent coverage and accuracy improvements have accelerated the development of clinical exome sequencing (CES) platforms targeting disease-related genes and enabling variant identification in patients with suspected genetic diseases. Nowadays, CES is rapidly becoming the diagnostic test of choice in patients with suspected Mendelian diseases, especially for those with heterogeneous etiology and clinical presentation. Reporting large CES series can improve guidelines on best practices for test utilization, and a better variant interpretation through clinically oriented data sharing.Herein, we suggest a feasible CES procedure for the genetic testing of Cerebral Cavernous Malformation (CCM) disease, including proband identification, library preparation, data analysis, and variant interpretation.


Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Testes Genéticos , Hemangioma Cavernoso do Sistema Nervoso Central/diagnóstico , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Sequenciamento de Nucleotídeos em Larga Escala , Alelos , Biologia Computacional/métodos , Variações do Número de Cópias de DNA , Gerenciamento Clínico , Estudos de Associação Genética/métodos , Testes Genéticos/métodos , Genômica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Proteínas Associadas aos Microtúbulos/genética , Mutação , Linhagem , Fenótipo , Sequenciamento do Exoma
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