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1.
Leukemia ; 38(5): 1107-1114, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38459167

RESUMO

Axicabtagene ciloleucel showed efficacy for relapsed/refractory large B-cell lymphomas (LBCL), including primary mediastinal B-cell lymphomas (PMBCL); however, only few PMBCLs were reported. Aim was to evaluate efficacy and safety of axicabtagene ciloleucel in patients with PMBCL compared to those with other LBCL, enrolled in the Italian prospective observational CART-SIE study. PMBCLs (n = 70) were younger, with higher percentage of bulky and refractory disease, compared to other LBCLs (n = 190). Median follow-up time for infused patients was 12.17 months (IQR 5.53,22.73). The overall (complete + partial) response rate (ORR,CR + PR) after bridging was 41% for PMBCL and 28% for other LBCL, p = 0.0102. Thirty days ORR was 78% (53/68) with 50% (34) CR in PMBCL, and 75% (141/187) with 53% (100) CR in other LBCL, p = 0.5457. Ninety days ORR was 69% (45/65) with 65% (42) CR in PMBCL, and 54% (87/162) with 47% (76) CR in other LBCL; progressive disease was 21% in PMBCL and 45% in other LBCL, p = 0.0336. Twelve months progression-free survival was 62% (95% CI: 51-75) in PMBCL versus 48% (95% CI: 41-57) in other LBCL, p = 0.0386. Twelve months overall survival was 86% (95% CI: 78-95) in PMBCL versus 71% (95% CI: 64-79) in other LBCL, p = 0.0034. All grade cytokine release syndrome was 88% (228/260); all grade neurotoxicity was 34% (88/260), with 6% of fatal events in PMBCL. Non-relapse mortality was 3%. In conclusion, PMBCLs achieved significantly better response and survival rates than other LBCLs.


Assuntos
Produtos Biológicos , Linfoma Difuso de Grandes Células B , Neoplasias do Mediastino , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/mortalidade , Feminino , Masculino , Pessoa de Meia-Idade , Produtos Biológicos/uso terapêutico , Neoplasias do Mediastino/patologia , Neoplasias do Mediastino/tratamento farmacológico , Neoplasias do Mediastino/mortalidade , Adulto , Estudos Prospectivos , Itália/epidemiologia , Idoso , Imunoterapia Adotiva/métodos , Seguimentos , Taxa de Sobrevida , Antígenos CD19 , Resultado do Tratamento
2.
Blood Adv ; 8(8): 1968-1980, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38359407

RESUMO

ABSTRACT: CD19-directed chimeric antigen receptor (CAR) T cells can induce durable remissions in relapsed/refractory large B-cell lymphomas (R/R LBCLs), but 60% of patients do not respond or relapse. Biological mechanisms explaining lack of response are emerging, but they are largely unsuccessful in predicting disease response at the patient level. Additionally, to maximize the cost-effectiveness of CAR T-cell therapy, biomarkers able to predict response and survival before CAR T-cell manufacturing would be desirable. We performed transcriptomic and functional evaluations of leukapheresis products in 95 patients with R/R LBCL enrolled in a prospective observational study, to identify correlates of response and survival to tisagenlecleucel and axicabtagene ciloleucel. A signature composed of 4 myeloid genes expressed by T cells isolated from leukapheresis products is able to identify patients with a very short progression-free survival (PFS), highlighting the impact of monocytes in CAR T-cell therapy response. Accordingly, response and PFS were also negatively influenced by high circulating absolute monocyte counts at the time of leukapheresis. The combined evaluation of peripheral blood monocytes at the time of leukapheresis and the 4-gene signature represents a novel tool to identify patients with R/R LBCL at very high risk of progression after CAR T-cell therapy and could be used to plan trials evaluating CAR T cells vs other novel treatments or allogeneic CAR T cells. However, it also highlights the need to incorporate monocyte depletion strategies for better CAR T production.


Assuntos
Linfoma Difuso de Grandes Células B , Receptores de Antígenos Quiméricos , Humanos , Imunoterapia Adotiva/efeitos adversos , Receptores de Antígenos Quiméricos/genética , Monócitos , Leucaférese , Recidiva Local de Neoplasia , Linfoma Difuso de Grandes Células B/terapia , Antígenos CD19
3.
Stud Health Technol Inform ; 301: 83-88, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37172158

RESUMO

BACKGROUND: Rehabilitation plays a key role in the recovery of upper extremity function after breast cancer surgery. Motion capture (mocap) systems for serious gaming have shown the potential to enable home-based rehabilitation, but clinical accuracy needs to be examined. OBJECTIVES: Validation of markerless mocap systems for telerehabilitation after breast cancer surgical intervention. METHODS: The accuracy of the markerless mocap device Azure Kinect in detecting compensatory movements and postural disturbances has been compared to a gold standard Optitrack system in five volunteers. Subsequently, a serious game for mocap-based shoulder exercises has been developed and integrated into a telerehabilitation platform. RESULTS: The Azure Kinect shows good reliability for scapular elevation (ICC >0.80; MAE <2.1 cm) and trunk tilt (ICC=0.88; MAE=5°), moderate reliability for rounded shoulders (ICC=0.51; MAE=2.6cm) and poor reliability for kyphosis angle (ICC=0.22; MAE=18°). CONCLUSION: The Azure Kinect provides reasonable performance for shoulder rehabilitation. The proposed telerehabilitation platform has been tested by rehabilitation specialists and received positive feedback.


Assuntos
Neoplasias da Mama , Telerreabilitação , Humanos , Feminino , Neoplasias da Mama/cirurgia , Reprodutibilidade dos Testes , Terapia por Exercício , Fenômenos Biomecânicos
4.
Cell Death Dis ; 14(3): 197, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36918555

RESUMO

Females have a lower probability to develop somatic cancers and a better response to chemotherapy than males. However, the reasons for these differences are still not well understood. The X-linked gene TSPY-Like 2 (TSPYL2) encodes for a putative tumor suppressor protein involved in cell cycle regulation and DNA damage response (DDR) pathways. Here, we demonstrate that in unstressed conditions TSPYL2 is maintained at low levels by MDM2-dependent ubiquitination and proteasome degradation. Upon genotoxic stress, E2F1 promotes TSPYL2 expression and protein accumulation in non-transformed cell lines. Conversely, in cancer cells, TSPYL2 accumulates only in females or in those male cancer cells that lost the Y-chromosome during the oncogenic process. Hence, we demonstrate that while TSPYL2 mRNA is induced in all the tested tumor cell lines after DNA damage, TSPYL2 protein stability is increased only in female cancer cells. Indeed, we found that TSPYL2 accumulation, in male cancer cells, is prevented by the Y-encoded protein SRY, which modulates MDM2 protein levels. In addition, we demonstrated that TSPYL2 accumulation is required to sustain cell growth arrest after DNA damage, possibly contributing to protect normal and female cancer cells from tumor progression. Accordingly, TSPYL2 has been found more frequently mutated in female-specific cancers. These findings demonstrate for the first time a sex-specific regulation of TSPYL2 in the DDR of cancer cells and confirm the existence of sexual dimorphism in DNA surveillance pathways.


Assuntos
Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Neoplasias , Feminino , Humanos , Masculino , Ciclo Celular/fisiologia , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células , Dano ao DNA/genética , Neoplasias/genética , Proteínas Supressoras de Tumor/genética , Proteínas de Ligação a DNA/genética
5.
Clin Cancer Res ; 28(15): 3378-3386, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35583610

RESUMO

PURPOSE: In clinical trials, the expansion and persistence of chimeric antigen receptor (CAR) T cells correlate with therapeutic efficacy. However, properties of CAR T cells that enable their in vivo proliferation have still to be consistently defined and the role of CAR T bag content has never been investigated in a real-life setting. EXPERIMENTAL DESIGN: Residual cells obtained after washing 61 anti-CD19 CAR T product bags were analyzed to identify tisagenlecleucel/Tisa-cel and axicabtagene ciloleucel/Axi-cel phenotypic features associated with postinfusion CAR T-cell in vivo expansion and with response and survival. RESULTS: While Tisa-cel was characterized by a significant enrichment in CAR+CD4+ T cells with central memory (P < 0.005) and effector (P < 0.005) phenotypes and lower rates of CAR+CD8+ with effector memory (P < 0.005) and naïve-like (P < 0.05) phenotypes as compared with Axi-cel, the two products displayed similar expansion kinetics. In vivo CAR T-cell expansion was influenced by the presence of CAR T with a CD8+ T central memory signature (P < 0.005) in both Tisa-cel and Axi-cel infusion products and was positively associated with response and progression-free survival (P < 0.05). CONCLUSIONS: Our data indicate that despite the great heterogeneity of Tisa-cel and Axi-cel products, the differentiation status of the infused cells mediates CAR T-cell in vivo proliferation that is necessary for antitumor response.


Assuntos
Linfoma Difuso de Grandes Células B , Receptores de Antígenos Quiméricos , Antígenos CD19/uso terapêutico , Humanos , Imunoterapia Adotiva , Linfoma Difuso de Grandes Células B/patologia , Fenótipo , Receptores de Antígenos Quiméricos/genética , Linfócitos T
6.
Int J Mol Sci ; 23(7)2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35409194

RESUMO

Mature T-cell lymphomas (MTCLs) represent a heterogeneous group of aggressive non-Hodgkin lymphomas comprising different entities. Anthracycline-based regimens are considered the standard of care in the front-line treatment. However, responses to these approaches have been neither adequate nor durable, and new treatment strategies are urgently needed to improve survival. Genomic instability is a common feature of cancer cells and can be caused by aberrations in the DNA damage response (DDR) and DNA repair mechanisms. Consistently, molecules involved in DDR are being targeted to successfully sensitize cancer cells to chemotherapy. Recent studies showed that some hematological malignancies display constitutive DNA damage and intrinsic DDR activation, but these features have not been investigated yet in MTCLs. In this study, we employed a panel of malignant T cell lines, and we report for the first time the characterization of intrinsic DNA damage and basal DDR activation in preclinical models in T-cell lymphoma. Moreover, we report the efficacy of targeting the apical kinase ATM using the inhibitor AZD0156, in combination with standard chemotherapy to promote apoptotic cell death. These findings suggest that DDR is an attractive pathway to be pharmacologically targeted when developing novel therapies and improving MTCL patients' outcomes.


Assuntos
Linfoma não Hodgkin , Linfoma de Células T , Antraciclinas/farmacologia , Antraciclinas/uso terapêutico , Antibióticos Antineoplásicos , Dano ao DNA , Reparo do DNA , Humanos , Linfoma de Células T/tratamento farmacológico , Linfoma de Células T/genética
7.
Br J Haematol ; 196(3): 548-558, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34649298

RESUMO

Patients affected by lymphoid malignancies (LM) are frequently immune-compromised, suffering increased mortality from COVID-19. This prospective study evaluated serological and T-cell responses after complete mRNA vaccination in 263 patients affected by chronic lymphocytic leukaemia, B- and T-cell lymphomas and multiple myeloma. Results were compared with those of 167 healthy subjects matched for age and sex. Overall, patient seroconversion rate was 64·6%: serological response was lower in those receiving anti-cancer treatments in the 12 months before vaccination: 55% vs 81·9% (P < 0·001). Anti-CD20 antibody plus chemotherapy treatment was associated with the lowest seroconversion rate: 17·6% vs. 71·2% (P < 0·001). In the multivariate analysis conducted in the subgroup of patients on active treatment, independent predictors for seroconversion were: anti-CD20 treatment (P < 0·001), aggressive B-cell lymphoma diagnosis (P = 0·002), and immunoglobulin M levels <40 mg/dl (P = 0·030). The T-cell response was evaluated in 99 patients and detected in 85 of them (86%). Of note, 74% of seronegative patients had a T-cell response, but both cellular and humoral responses were absent in 13·1% of cases. Our findings raise some concerns about the protection that patients with LM, particularly those receiving anti-CD20 antibodies, may gain from vaccination. These patients should strictly maintain all the protective measures.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Vacina BNT162/administração & dosagem , COVID-19 , Neoplasias Hematológicas , Imunidade Celular/efeitos dos fármacos , Transtornos Linfoproliferativos , SARS-CoV-2/imunologia , Linfócitos T/imunologia , Vacina de mRNA-1273 contra 2019-nCoV/imunologia , Idoso , Anticorpos Antivirais/imunologia , Vacina BNT162/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Feminino , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/imunologia , Humanos , Imunoglobulina M/imunologia , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Soroconversão
8.
Haematologica ; 106(11): 2918-2926, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33054126

RESUMO

Nodal peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) remains a diagnosis encompassing a heterogenous group of PTCL cases not fitting criteria for more homogeneous subtypes. They are characterized by a poor clinical outcome when treated with anthracycline-containing regimens. A better understanding of their biology could improve prognostic stratification and foster the development of novel therapeutic approaches. Recent targeted and whole exome sequencing studies have shown recurrent copy number abnormalities (CNAs) with prognostic significance. Here, investigating 5 formalin-fixed, paraffin embedded cases of PTCL-NOS by whole genome sequencing (WGS), we found a high prevalence of structural variants and complex events, such as chromothripsis likely responsible for the observed CNAs. Among them, CDKN2A and PTEN deletions emerged as the most frequent aberration, as confirmed in a final cohort of 143 patients with nodal PTCL. The incidence of CDKN2A and PTEN deletions among PTCL-NOS was 46% and 26%, respectively. Furthermore, we found that co-occurrence of CDKN2A and PTEN deletions is an event associated with PTCL-NOS with absolute specificity. In contrast, these deletions were rare and never co-occurred in angioimmunoblastic and anaplastic lymphomas. CDKN2A deletion was associated with shorter overall survival in multivariate analysis corrected by age, IPI, transplant eligibility and GATA3 expression (adjusted HR =2.53; 95% CI 1.006-6.3; p=0.048). These data suggest that CDKN2A deletions may be relevant for refining the prognosis of PTCL-NOS and their significance should be evaluated in prospective trials.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/genética , Linfoma de Células T Periférico , Antraciclinas , Estudos de Coortes , Deleção de Genes , Humanos , Linfoma de Células T Periférico/diagnóstico , Linfoma de Células T Periférico/genética , PTEN Fosfo-Hidrolase , Prognóstico , Estudos Prospectivos
9.
Br J Cancer ; 121(7): 567-577, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31474759

RESUMO

BACKGROUND: Anthracycline-containing regimens, namely cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) or CHOEP (CHOP + etoposide), represent the current standard of care for patients with newly diagnosed peripheral T-cell lymphomas (PTCLs), although responses are unsatisfactory. In this study, we investigated the pathways able to mitigate the sensitivity to CHOP-based regimens in preclinical models of T-cell lymphoma (TCL) to select agents for the development of CHOP-based drug combinations. METHODS: We performed gene expression profiling of malignant T-cell lines exposed to CHOEP; flow cytometry was employed to study the effects of drug combinations on cell viability, cell cycle distribution, apoptosis and mitochondrial membrane depolarisation. Western blot analyses were performed to study cell signalling downstream of the T-cell receptor and apoptosis. The in vivo effect of the drug combination was tested in xenograft models. RESULTS: We highlighted a modulation of tyrosine kinases belonging to the T-cell receptor pathway upon chemotherapy that provided the rationale for combining the tyrosine kinase inhibitor dasatinib with CHOEP. Dasatinib improves CHOEP activity and reduces viability in vitro. Furthermore, combination treatment results in tumour growth inhibition in in vivo xenograft mouse models. CONCLUSIONS: Our data provide the rationale for clinical testing of the dasatinib-CHOEP combination in patients with T-cell lymphoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Células T/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Receptores de Antígenos de Linfócitos T/efeitos dos fármacos , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Apoptose , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular , Ciclofosfamida/administração & dosagem , Dasatinibe/administração & dosagem , Doxorrubicina/administração & dosagem , Esquema de Medicação , Sinergismo Farmacológico , Etoposídeo/administração & dosagem , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Humanos , Células Jurkat , Linfoma de Células T/genética , Linfoma de Células T/metabolismo , Camundongos Endogâmicos NOD , Camundongos SCID , Prednisona/administração & dosagem , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-fyn/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Resultado do Tratamento , Regulação para Cima/efeitos dos fármacos , Vincristina/administração & dosagem , Proteína rhoA de Ligação ao GTP/genética
10.
Cell Death Differ ; 26(5): 918-931, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30050056

RESUMO

Protein acetylation and deacetylation events are finely regulated by lysine-acetyl-transferases and lysine-deacetylases and constitute an important tool for the activation or inhibition of specific cellular pathways. One of the most important lysine-acetyl-transferases is p300, which is involved in the regulation of gene expression, cell growth, DNA repair, differentiation, apoptosis, and tumorigenesis. A well-known target of p300 is constituted by the tumor suppressor protein p53, which plays a critical role in the maintenance of genomic stability and whose activity is known to be controlled by post-translational modifications, among which acetylation. p300 activity toward p53 is negatively regulated by the NAD-dependent deacetylase SIRT1, which deacetylates p53 preventing its transcriptional activation and the induction of p53-dependent apoptosis. However, the mechanisms responsible for p53 regulation by p300 and SIRT1 are still poorly understood. Here we identify the nucleosome assembly protein TSPY-Like 2 (TSPYL2, also known as TSPX, DENTT, and CDA1) as a novel regulator of SIRT1 and p300 function. We demonstrate that, upon DNA damage, TSPYL2 inhibits SIRT1, disrupting its association with target proteins, and promotes p300 acetylation and activation, finally stimulating p53 acetylation and p53-dependent cell death. Indeed, in response to DNA damage, cells silenced for TSPYL2 were found to be defective in p53 activation and apoptosis induction and these events were shown to be dependent on SIRT1 and p300 function. Collectively, our results shed new light on the regulation of p53 acetylation and activation and reveal a novel TSPYL2 function with important implications in cancerogenesis.


Assuntos
Proteína p300 Associada a E1A/genética , Neoplasias Pulmonares/genética , Proteínas Nucleares/genética , Sirtuína 1/genética , Proteína Supressora de Tumor p53/genética , Células A549 , Acetilação/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Camptotecina/farmacologia , Proliferação de Células/efeitos dos fármacos , Montagem e Desmontagem da Cromatina/genética , Dano ao DNA/efeitos dos fármacos , Proteínas de Ligação a DNA , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Etoposídeo/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Processamento de Proteína Pós-Traducional/genética , Ativação Transcricional/efeitos dos fármacos , Gencitabina
11.
J Chromatogr A ; 1581-1582: 63-70, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30446267

RESUMO

A new class of foreign substances present in the unsaponifiable fraction of vegetable oils undergone to chemical interesterification was systematically investigated. Their chemical structure, corresponding to dialkyl ketones (DAK) molecules, was elucidated both by gas chromatography-mass spectrometry (GC-MS), and liquid chromatography-high resolution mass spectrometry (LC-HRMS). An analytical protocol aimed to qualitative and quantitative detection of DAK molecules in vegetable oils of confectionery industry interest was developed. Being the range of concentration levels to be evaluated dependent on the technological task of interesterification process, the quantitation step was thoroughly examined. All the validation parameters were satisfactory and particularly the concentration determinations were made more reliable by the contemporary use of several quantitation standards. GC-MS and LC-HRMS analytical techniques exhibited comparable performances even if the second one shown better detection sensitivity.


Assuntos
Cromatografia de Fase Reversa , Cromatografia Gasosa-Espectrometria de Massas , Cetonas/análise , Lipídeos/química , Espectrometria de Massas em Tandem , Cromatografia Líquida , Óleos de Plantas/química
12.
Mutat Res Rev Mutat Res ; 776: 1-9, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29807573

RESUMO

Cell cycle and apoptosis regulator 2 (CCAR2 or DBC1) is a human protein recently emerged as a novel and important player of the DNA damage response (DDR). Indeed, upon genotoxic stress, CCAR2, phosphorylated by the apical DDR kinases ATM and ATR, increases its binding to the NAD+-dependent histone deacetylase SIRT1 and inhibits SIRT1 activity. This event promotes the acetylation and activation of p53, a SIRT1 target, and the subsequent induction of p53 dependent apoptosis. In addition, CCAR2 influences DNA repair pathway choice and promotes the chromatin relaxation necessary for the repair of heterochromatic DNA lesions. However, besides DDR, CCAR2 is involved in several other cellular functions. Indeed, through the interaction with transcription factors, nuclear receptors, epigenetic modifiers and RNA polymerase II, CCAR2 regulates transcription and transcript elongation. Moreover, promoting Rev-erbα protein stability and repressing BMAL1 and CLOCK expression, it was reported to modulate the circadian rhythm. Through SIRT1 inhibition, CCAR2 is also involved in metabolism control and, suppressing RelB and p65 activities in the NFkB pathway, it restricts B cell proliferation and immunoglobulin production. Notably, CCAR2 expression is deregulated in several tumors and, compared to the non-neoplastic counterpart, it may be up- or down-regulated. Since its up-regulation in cancer patients is usually associated with poor prognosis and its depletion reduces cancer cell growth in vitro, CCAR2 was suggested to act as a tumor promoter. However, there is also evidence that CCAR2 functions as a tumor suppressor and therefore its role in cancer formation and progression is still unclear. In this review we discuss CCAR2 functions in the DDR and its multiple biological activities in unstressed cells.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Dano ao DNA/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Apoptose/genética , Apoptose/fisiologia , Linfócitos B/imunologia , Linfócitos B/fisiologia , Senescência Celular/genética , Senescência Celular/fisiologia , Montagem e Desmontagem da Cromatina/genética , Montagem e Desmontagem da Cromatina/fisiologia , Relógios Circadianos/genética , Relógios Circadianos/fisiologia , Dano ao DNA/genética , Reparo do DNA/genética , Reparo do DNA/fisiologia , Epigênese Genética , Humanos , Modelos Biológicos , Mutação , Neoplasias/etiologia , Sirtuína 1/genética , Sirtuína 1/fisiologia , Transcrição Gênica , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/fisiologia
13.
Foods ; 7(2)2018 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-29462917

RESUMO

Interesterification is an industrial transformation process aiming to change the physico-chemical properties of vegetable oils by redistributing fatty acid position within the original constituent of the triglycerides. In the confectionery industry, controlling formation degree of positional isomers is important in order to obtain fats with the desired properties. Silver ion HPLC (High Performance Liquid Chromatography) is the analytical technique usually adopted to separate triglycerides (TAGs) having different unsaturation degrees. However, separation of TAG positional isomers is a challenge when the number of double bonds is the same and the only difference is in their position within the triglyceride molecule. The TAG positional isomers involved in the present work have a structural specificity that require a separation method tailored to the needs of confectionery industry. The aim of this work was to obtain a chromatographic resolution that might allow reliable qualitative and quantitative evaluation of TAG positional isomers within reasonably rapid retention times and robust in respect of repeatability and reproducibility. The resulting analytical procedure was applied both to confectionery raw materials and final products.

14.
Cell Death Dis ; 7(11): e2453, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27809307

RESUMO

Human CCAR2 has recently emerged as having a pivotal role in the DNA damage response, promoting apoptosis and repair of heterochromatic DNA breaks. However, less is known about the function of CCAR2 in tumor formation and cancer progression. Here, we demonstrate, for the first time, that CCAR2 loss inhibits the proliferation of cancer cells, but preserves the growth of normal cells. Investigating the mechanisms responsible for this differential effect, we found that CCAR2 depletion specifically impairs the activation of AKT pathway in cancer cells, but not in normal cells, by reducing AKT phosphorylation on Ser473. This effect is achieved through the transcriptional upregulation of TRB3 gene and accumulation of TRB3 protein, which then binds to and inhibits the phosphorylation and activation of AKT. The defective activation of AKT finally results in reduced GSK3ß phosphorylation, prevention of G1/S transition and inhibition of cancer cell growth. These results establish an important role for CCAR2 in cancer cells proliferation and could shed new light on novel therapeutic strategies against cancer, devoid of detrimental side effects.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Ativação Enzimática , Fase G1 , Humanos , Fosforilação , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Repressoras/metabolismo , Fase S
15.
Oncotarget ; 6(19): 17817-31, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-26158765

RESUMO

Cell cycle and apoptosis regulator 2 (CCAR2, formerly known as DBC1) is a nuclear protein largely involved in DNA damage response, apoptosis, metabolism, chromatin structure and transcription regulation. Upon DNA lesions, CCAR2 is phosphorylated by the apical kinases ATM/ATR and this phosphorylation enhances CCAR2 binding to SIRT1, leading to SIRT1 inhibition, p53 acetylation and p53-dependent apoptosis. Recently, we found that also the checkpoint kinase Chk2 and the proteasome activator REGγ are required for efficient CCAR2-mediated inhibition of SIRT1 and induction of p53-dependent apoptosis.Here, we report that CCAR2 is required for the repair of heterochromatic DNA lesions, as cells knock-out for CCAR2 retain, at late time-points after genotoxic treatment, abnormal levels of DNA damage-associated nuclear foci, whose timely resolution is reinstated by HP1ß depletion. Conversely, repair of DNA damages in euchromatin are not affected by CCAR2 absence.We also report that the impairment in heterochromatic DNA repair is caused by defective Chk2 activation, detectable in CCAR2 ablated cells, which finally impacts on the phosphorylation of the Chk2 substrate KAP1 that is required for the induction of heterochromatin relaxation and DNA repair.These studies further extend and confirm the role of CCAR2 in the DNA damage response and DNA repair and illustrate a new mechanism of Chk2 activity regulation. Moreover, the involvement of CCAR2 in the repair of heterochromatic DNA breaks suggests a new role for this protein in the maintenance of chromosomal stability, which is necessary to prevent cancer formation.


Assuntos
Quinase do Ponto de Checagem 2/metabolismo , Dano ao DNA/fisiologia , Reparo do DNA/fisiologia , Proteínas Repressoras/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Western Blotting , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Homólogo 5 da Proteína Cromobox , Imunofluorescência , Técnicas de Inativação de Genes , Humanos , Imunoprecipitação , Proteínas do Tecido Nervoso , Fosforilação , RNA Interferente Pequeno , Transfecção , Proteína 28 com Motivo Tripartido
16.
Nucleic Acids Res ; 42(21): 13150-60, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25361978

RESUMO

Human DBC1 (Deleted in Breast Cancer 1; KIAA1967; CCAR2) is a protein implicated in the regulation of apoptosis, transcription and histone modifications. Upon DNA damage, DBC1 is phosphorylated by ATM/ATR on Thr454 and this modification increases its inhibitory interaction with SIRT1, leading to p53 acetylation and p53-dependent apoptosis. Here, we report that the inhibition of SIRT1 by DBC1 in the DNA damage response (DDR) also depends on Chk2, the transducer kinase that is activated by ATM upon DNA lesions and contributes to the spreading of DNA damage signal. Indeed we found that inactivation of Chk2 reduces DBC1-SIRT1 binding, thus preventing p53 acetylation and DBC1-induced apoptosis. These events are mediated by Chk2 phosphorylation of the 11S proteasome activator REGγ on Ser247, which increases REGγ-DBC1 interaction and SIRT1 inhibition. Overall our results clarify the mechanisms underlying the DBC1-dependent SIRT1 inhibition and link, for the first time, Chk2 and REGγ to the ATM-DBC1-SIRT1 axis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose , Autoantígenos/metabolismo , Quinase do Ponto de Checagem 2/metabolismo , Dano ao DNA , Complexo de Endopeptidases do Proteassoma/metabolismo , Sirtuína 1/metabolismo , Linhagem Celular Tumoral , Humanos , Sirtuína 1/antagonistas & inibidores
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