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1.
Blood ; 141(26): 3166-3183, 2023 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-37084385

RESUMO

Dysregulation of messenger RNA (mRNA) translation, including preferential translation of mRNA with complex 5' untranslated regions such as the MYC oncogene, is recognized as an important mechanism in cancer. Here, we show that both human and murine chronic lymphocytic leukemia (CLL) cells display a high translation rate, which is inhibited by the synthetic flavagline FL3, a prohibitin (PHB)-binding drug. A multiomics analysis performed in samples from patients with CLL and cell lines treated with FL3 revealed the decreased translation of the MYC oncogene and of proteins involved in cell cycle and metabolism. Furthermore, inhibiting translation induced a proliferation arrest and a rewiring of MYC-driven metabolism. Interestingly, contrary to other models, the RAS-RAF-(PHBs)-MAPK pathway is neither impaired by FL3 nor implicated in translation regulation in CLL cells. Here, we rather show that PHBs are directly associated with the eukaryotic initiation factor (eIF)4F translation complex and are targeted by FL3. Knockdown of PHBs resembled FL3 treatment. Importantly, inhibition of translation controlled CLL development in vivo, either alone or combined with immunotherapy. Finally, high expression of translation initiation-related genes and PHBs genes correlated with poor survival and unfavorable clinical parameters in patients with CLL. Overall, we demonstrated that translation inhibition is a valuable strategy to control CLL development by blocking the translation of several oncogenic pathways including MYC. We also unraveled a new and direct role of PHBs in translation initiation, thus creating new therapeutic opportunities for patients with CLL.


Assuntos
Leucemia Linfocítica Crônica de Células B , Humanos , Camundongos , Animais , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Fator de Iniciação 4F em Eucariotos/genética , Proibitinas , Genes myc , RNA Mensageiro/genética
2.
Liver Transpl ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38727607

RESUMO

In a setting characterized by a growing prevalence of patients with alcohol-associated and metabolic dysfunction-associated steatotic liver diseases, coupled with an aging patient demographic, the incidence of cardiac comorbidities in liver transplant candidates is on the rise. These comorbidities not only pose barriers to transplant eligibility but also impact the intraoperative course and affect posttransplant outcomes. As such, there is a significant need to optimize the clinical management of these cardiac comorbidities. However, there is a scarcity of evidence regarding the best practices for managing cardiac comorbidities such as coronary and valvular heart diseases, arrhythmia, and cardiomyopathy in this population, both before and during transplant surgery. These conditions necessitate a coordinated and multidisciplinary approach to care. In this manuscript, we conduct a comprehensive review of the most recent evidence pertaining to the preoperative and intraoperative management of these cardiac comorbidities in liver transplant candidates. Our aim is to provide recommendations that improve and standardize their clinical care.

3.
Liver Int ; 44(8): 1912-1923, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38591767

RESUMO

BACKGROUND: The optimal cardiovascular assessment of liver transplant (LT) candidates is unclear. We aimed to evaluate the performance of CT-based coronary tests (coronary artery calcium score [CACS] and coronary CT angiography [CCTA]) and a modification of the CAD-LT score (mCAD-LT, excluding family history of CAD) to diagnose significant coronary artery disease (CAD) before LT and predict the incidence of post-LT cardiovascular events (CVE). METHODS: We retrospectively analysed a single-centre cohort of LT candidates who underwent non-invasive tests; invasive coronary angiography (ICA) was performed depending on the results of non-invasive tests. mCAD-LT was calculated in all patients. RESULTS: Six-hundred-and-thirty-four LT candidates were assessed and 351 of them underwent LT. CACS, CCTA and ICA were performed in 245, 123 and 120 LT candidates, respectively. Significant CAD was found in 30% of patients undergoing ICA. The AUROCs of mCAD-LT (.722) and CCTA (.654) were significantly higher than that of CACS (.502) to predict the presence of significant CAD. Specificity of the tests ranged between 31% for CCTA and 53% for CACS. Among patients who underwent LT, CACS ≥ 400 and mCAD-LT were independently associated with the incidence of CVE; in patients who underwent CCTA before LT, significant CAD at CCTA also predicted post-LT CVE. CONCLUSION: In this cohort, mCAD-LT score and CT-based tests detect the presence of significant CAD in LT candidates, although they tend to overestimate it. Both mCAD-LT score and CT-based tests classify LT recipients according to their risk of post-LT CVE and can be used to improve post-LT risk mitigation.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana , Transplante de Fígado , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Transplante de Fígado/efeitos adversos , Medição de Risco , Idoso , Valor Preditivo dos Testes , Calcificação Vascular/diagnóstico por imagem , Adulto , Fatores de Risco
4.
Haematologica ; 108(11): 3011-3024, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37345470

RESUMO

Chronic lymphocytic leukemia (CLL) cells are highly dependent on interactions with the immunosuppressive tumor microenvironment (TME) for survival and proliferation. In the search for novel treatments, pro-inflammatory cytokines have emerged as candidates to reactivate the immune system. Among those, interleukin 27 (IL-27) has recently gained attention, but its effects differ among malignancies. Here, we utilized the Eµ-TCL1 and EBI3 knock-out mouse models as well as clinical samples from patients to investigate the role of IL-27 in CLL. Characterization of murine leukemic spleens revealed that the absence of IL-27 leads to enhanced CLL development and a more immunosuppressive TME in transgenic mice. Gene-profiling of T-cell subsets from EBI3 knock-out highlighted transcriptional changes in the CD8+ T-cell population associated with T-cell activation, proliferation, and cytotoxicity. We also observed an increased anti-tumor activity of CD8+ T cells in the presence of IL-27 ex vivo with murine and clinical samples. Notably, IL-27 treatment led to the reactivation of autologous T cells from CLL patients. Finally, we detected a decrease in IL-27 serum levels during CLL development in both pre-clinical and patient samples. Altogether, we demonstrated that IL-27 has a strong anti-tumorigenic role in CLL and postulate this cytokine as a promising treatment or adjuvant for this malignancy.


Assuntos
Interleucina-27 , Leucemia Linfocítica Crônica de Células B , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos , Citocinas , Imunossupressores , Leucemia Linfocítica Crônica de Células B/patologia , Camundongos Transgênicos , Subpopulações de Linfócitos T/patologia , Microambiente Tumoral
5.
Clin Gastroenterol Hepatol ; 20(3): e380-e397, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33279783

RESUMO

BACKGROUND & AIMS: Few prospective studies have assessed the safety of direct oral anticoagulants (DOACs) in elective endoscopy. Our primary aim was to compare the risks of endoscopy-related gastrointestinal bleeding and thromboembolic events in patients on DOACs or vitamin K antagonists (VKAs) in this setting. Secondarily, we examined the impact of the timing of anticoagulant resumption on the risk of delayed bleeding in high-risk therapeutic procedures. METHODS: We conducted a multicenter, prospective, observational study from January 2018 to March 2020 of 1602 patients on oral anticoagulants (1004 on VKAs and 598 on DOACs) undergoing 1874 elective endoscopic procedures. Our primary outcomes were 90-day thromboembolic events and 30-day endoscopy-related gastrointestinal bleeding. The inverse probability of treatment weighting propensity score method was used for baseline covariate adjustment. RESULTS: The 2 groups had similar risks of endoscopy-related gastrointestinal bleeding (VKAs vs DOACs, 6.2% vs 6.7%; adjusted odds ratio [OR], 1.05; 95% CI, 0.67-1.65) and thromboembolic events (VKAs vs DOACs, 1.3% vs 1.5%; adjusted OR, 0.90; 95% CI, 0.34-2.38). In high bleeding risk procedures (n = 747), delayed anticoagulant resumption (> 48 hours or 24-48 hours vs < 24 hours) did not reduce the risk of postprocedural bleeding (10.3%, 9%, and 5.8%, respectively; adjusted P = .43). Hot and cold snare polypectomy were the most frequent high-risk interventions (41.8% and 39.8%, respectively). CONCLUSION: In a prospective study of patients on DOACs or VKAs undergoing elective endoscopy, endoscopy-related bleeding and thromboembolic events showed similar risk. Our study suggests that early anticoagulant resumption is safe in most patients, but more data are needed for advanced high-risk therapeutic procedures.


Assuntos
Pólipos do Colo , Administração Oral , Anticoagulantes/efeitos adversos , Colonoscopia , Hemorragia Gastrointestinal/induzido quimicamente , Hemorragia Gastrointestinal/epidemiologia , Humanos , Estudos Prospectivos , Vitamina K
6.
Liver Transpl ; 28(8): 1332-1344, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35224857

RESUMO

Although liver transplantation (LT) recipients are at high cardiovascular risk (CVR), the management of CVR factors (CVRF) after LT is far from optimal and needs to be improved. For this reason, we developed a multidisciplinary protocol to standardize the identification, risk stratification, management, and targets of therapy of CVRF during the first post-LT year. The grade of identification and control of CVRF 12 months after LT in the postintervention cohort (LT January 2018-January 2020, n = 150) were compared with a control cohort who underwent LT between July 2015 and December 2016 (n = 100). Before LT, the prevalence of metabolic-associated fatty liver disease as the indication of LT and the presence of obesity were significantly higher in the postintervention cohort, whereas the prevalence of other CVRF and renal dysfunction tended to be higher. Cyclosporine A was used less frequently in the postintervention cohort, whereas everolimus tended to increase. At 12 months after LT, the proportion of patients with measured blood pressure (88% vs. 56%), glycosilated hemoglobin (HbA1c; 96% vs. 72%), and high-density lipoprotein/low-density lipoprotein cholesterol (67% vs. 33%) was higher in the postintervention than in the control cohort (all p < 0.001). Blood pressure (64% vs. 36%, p = 0.02) and HbA1c (85% vs. 70%, p = 0.1) were within target in more individuals with hypertension and diabetes mellitus, respectively, in the postintervention cohort. Median total cholesterol levels were lower in the postintervention (184 mg/dl; interquartile range [IQR], 160-210 mg/dl) than in the control cohort (212 mg/dl; IQR, 186-240 mg/dl; p = 0.02). At 2 years after LT, the incidence of cardiovascular events was 14% in the control cohort and 6% in the postintervention cohort (p = 0.063). In conclusion, a multidisciplinary, multiprofessional strategy can achieve a higher grade of assessment and management of post-LT CVR despite a worsening metabolic profile of LT recipients.


Assuntos
Doenças Cardiovasculares , Transplante de Fígado , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , LDL-Colesterol , Hemoglobinas Glicadas , Fatores de Risco de Doenças Cardíacas , Humanos , Transplante de Fígado/efeitos adversos , Fatores de Risco
7.
J Viral Hepat ; 29(9): 823-834, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35708160

RESUMO

Abnormal liver function tests (A-LFTs) during admission for coronavirus disease-19 (COVID-19) are frequent, but its evolution after COVID-19 resolution remains unexplored. We evaluated factors related to A-LFTs during COVID-19 and assessed the liver outcome after patients' discharge. This is a observational study including: (1) retrospective analysis of variables related to A-LFTs during COVID-19; and (2) follow-up evaluation with blood test, transient elastography and liver biopsy in those with persistent A-LFTs. A-LFTs were defined according to CTCAEv4.0. Among 595 patients, 366 (61.5%) showed A-LFTs. The ratio of partial pressure of oxygen and inspired oxygen fraction (P/F) below 200, ferritin ≥1000 ng/mL, male gender and antibiotic and immunomodulatory treatments were related to A-LFTs. Follow-up evaluation was performed in 153 individuals. Persistent A-LFTs at follow-up was similar in patients with/without A-LFTs during admission (14.1% vs. 4.9%, p = 0.104). Fifteen (93%) and 58 (39%) patients with/without A-LFTs at follow-up showed metabolic fatty liver disease criteria (p < 0.001), which were histologically confirmed. In conclusion, A-LFTs during COVID-19 were related to infection severity. Abnormalities remitted at follow-up in >80% of patients, and no correlation between A-LFTs at admission and at follow-up was found. Most patients with A-LFTs at follow-up had non-invasive and histologically proven fatty liver disease.


Assuntos
COVID-19 , Hepatopatias , Seguimentos , Humanos , Hepatopatias/diagnóstico , Testes de Função Hepática , Masculino , Oxigênio , RNA Viral , Estudos Retrospectivos , SARS-CoV-2
9.
Gastrointest Endosc ; 90(4): 581-590.e6, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31220444

RESUMO

BACKGROUND AND AIMS: TC-325 (Hemospray, Cook Medical, Winston-Salem, NC) is an inorganic hemostatic powder recently approved by the U.S. Food and Drug Administration. This study aimed to examine the effectiveness, safety, and predictors of TC-325 failure in a large real-life cohort. METHODS: This was a retrospective study conducted at 21 Spanish centers. All patients treated with TC-325 until September 2018 were included. The primary outcome was treatment failure, defined as failed intraprocedural hemostasis or recurrent bleeding within the first 30 postprocedural days. Secondary outcomes included safety and survival. Risk and predictors of failure were assessed via competing-risk models. RESULTS: The cohort comprised 261 patients, of whom 219 (83.9%) presented with upper gastrointestinal bleeding (GIB). The most common causes were peptic ulcer (28%), malignancy (18.4%), and therapeutic endoscopy-related GIB (17.6%). TC-325 was used as rescue therapy in 191 (73.2%) patients. The rate of intraprocedural hemostasis was 93.5% (95% confidence interval [CI], 90%-96%). Risks of TC-325 failure at postprocedural days 3, 7, and 30 were 21.1%, 24.6%, and 27.4%, respectively. On multivariate analysis, spurting bleeding (P = .004), use of vasoactive drugs (P = .02), and hypotension (P = .008) were independent predictors of failure. Overall 30-day survival was 81.9% (95% CI, 76%-86%) and intraprocedural hemostasis was associated with a better prognosis (adjusted hazard ratio, 0.29; P = .006). Two severe adverse events were noted. CONCLUSION: TC-325 was safe and effective for intraprocedural hemostasis in more than 90% of patients, regardless of the cause or site of bleeding and its use as rescue therapy. In this high-risk cohort treated with TC-325, the 30-day failure rate exceeded 25% and was highest with spurting bleeding or hemodynamic instability.


Assuntos
Hemorragia Gastrointestinal/tratamento farmacológico , Hemostáticos/uso terapêutico , Minerais/uso terapêutico , Hemorragia Pós-Operatória/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Endoscopia Gastrointestinal , Feminino , Hemorragia Gastrointestinal/etiologia , Neoplasias Gastrointestinais/complicações , Hemostase Endoscópica , Humanos , Masculino , Pessoa de Meia-Idade , Úlcera Péptica Hemorrágica/tratamento farmacológico , Recidiva , Estudos Retrospectivos , Falha de Tratamento
10.
EClinicalMedicine ; 74: 102737, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39114271

RESUMO

Background: The Gender-Equity Model for liver Allocation corrected by serum sodium (GEMA-Na) and the Model for End-stage Liver Disease 3.0 (MELD 3.0) could amend sex disparities for accessing liver transplantation (LT). We aimed to assess these inequities in Spain and to compare the performance of GEMA-Na and MELD 3.0. Methods: Nationwide cohort study including adult patients listed for a first elective LT (January 2016-December 2021). The primary outcome was mortality or delisting for sickness within the first 90 days. Independent predictors of the primary outcome were evaluated using multivariate Cox's regression with adjusted relative risks (RR) and 95% confidence intervals (95% CI). The discrimination of GEMA-Na and MELD 3.0was assessed using Harrell c-statistics (Hc). Findings: The study included 6071 patients (4697 men and 1374 women). Mortality or delisting for clinical deterioration occurred in 286 patients at 90 days (4.7%). Women had reduced access to LT (83.7% vs. 85.9%; p = 0.037) and increased risk of mortality or delisting for sickness at 90 days (adjusted RR = 1.57 [95% CI 1.09-2.28]; p = 0.017). Female sex remained as an independent risk factor when using MELD or MELD-Na but lost its significance in the presence of GEMA-Na or MELD 3.0. Among patients included for reasons other than tumours (n = 3606; 59.4%), GEMA-Na had Hc = 0.753 (95% CI 0.715-0.792), which was higher than MELD 3.0 (Hc = 0.726 [95% CI 0.686-0.767; p = 0.001), showing both models adequate calibration. Interpretation: GEMA-Na and MELD 3.0 might correct sex disparities for accessing LT, but GEMA-Na provides more accurate predictions of waiting list outcomes and could be considered the standard of care for waiting list prioritization. Funding: Instituto de Salud Carlos III, Agencia Estatal de Investigación (Spain), and European Union.

11.
Oncoimmunology ; 12(1): 2276490, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37937211

RESUMO

Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in the western world. It is characterized by a high dependency on interactions with the surrounding immune landscape, highlighting its suitability for immune-mediated therapeutic interventions. We recently revealed that the cytokine IL-27 exerts a strong anti-tumor role in CLL through a T-cell-mediated mechanism.


Assuntos
Interleucina-27 , Leucemia Linfocítica Crônica de Células B , Adulto , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Citocinas , Linfócitos T , Terapia de Imunossupressão
12.
Sci Total Environ ; 902: 166043, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37544451

RESUMO

Different marine sponge species from Tethys Bay, Antarctica, were analyzed for contamination by polyester and polyamide microplastics (MPs). The PISA (Polymer Identification and Specific Analysis) procedure was adopted as it provides, through depolymerization and HPLC analysis, highly sensitive mass-based quantitative data. The study focused on three analytes resulting from the hydrolytic depolymerization of polyesters and polyamides: terephthalic acid (TPA), 6-aminohexanoic acid (AHA), and 1-6-hexanediamine (HMDA). TPA is a comonomer found in the polyesters poly(ethylene terephthalate) (PET) and poly(butylene adipate co terephthalate) (PBAT), and in polyamides such as poly(1,4-p-phenylene terephthalamide) (Kevlar™ and Twaron™ fibers) and poly(hexamethylene terephthalamide) (nylon 6 T). AHA is the monomer of nylon 6. HMDA is a comonomer of the aliphatic nylon 6,6 (HMDA-co-adipic acid) and of semi-aromatic polyamides such as, again, nylon 6 T (HMDA-co-TPA). Except for the biodegradable PBAT, these polymers exhibit high to extreme mechanical, thermal and chemical resistance. Indeed, they are used as technofibers in protective clothing able to withstand extreme conditions as those typical of Antarctica. Of the two amine monomers, only HMDA was found above the limit of quantification, and only in specimens of Haliclona (Rhizoniera) scotti, at a concentration equivalent to 27 µg/kg of nylon 6,6 in the fresh sponge. Comparatively higher concentrations, corresponding to 2.5-4.1 mg/kg of either PBAT or PPTA, were calculated from the concentration of TPA detected in all sponge species. Unexpectedly, TPA did not originate from PET (the most common textile fiber) as it was detected in the acid hydrolysate, whereas the PISA procedure results in effective PET depolymerization only under alkaline conditions. The obtained results showed that sponges, by capturing and concentrating MPs from large volumes of filtered marine waters, may be considered as effective indicators of the level and type of pollution by MPs and provide early warnings of increasing levels of pollution even in remote areas.


Assuntos
Plásticos , Poríferos , Animais , Biomarcadores Ambientais , Nylons , Regiões Antárticas , Poliésteres , Microplásticos
13.
JMIR Cardio ; 6(1): e30661, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35103602

RESUMO

BACKGROUND: The COVID-19 pandemic forced several European governments to impose severe lockdown measures. The reduction of physical activity during the lockdown could have been deleterious. OBJECTIVE: The aim of this observational, retrospective study was to investigate the effect of the lockdown strategy on the physical activity burden and subsequent reassessment in a group of patients with heart failure who were followed by means of remote monitoring. METHODS: We analyzed remote monitoring transmissions during the 3-month period immediately preceding the lockdown, 69 days of lockdown, and 3-month period after the first lockdown in a cohort of patients with heart failure from a general hospital in Lombardy, Italy. We compared variation of daily physical activity measured by cardiac implantable electrical devices with clinical variables collected in a hospital database. RESULTS: We enrolled 41 patients with heart failure that sent 176 transmissions. Physical activity decreased during the lockdown period (mean 3.4, SD 1.9 vs mean 2.9, SD 1.8 hours/day; P<.001) but no significant difference was found when comparing the period preceding and following the lockdown (-0.0007 hours/day; P=.99). We found a significant correlation between physical activity reduction during and after the lockdown (R2=0.45, P<.001). The only significant predictor of exercise variation in the postlockdown period was the lockdown to prelockdown physical activity ratio. CONCLUSIONS: An excessive reduction of exercise in patients with heart failure decreased the tolerance to exercise, especially in patients with more comorbidities. Remote monitoring demonstrated exercise reduction, suggesting its potential utility to encourage patients to maintain their usual physical activity levels.

14.
J Liver Transpl ; 7: 100113, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38013988

RESUMO

Opportunistic infections, including fungal infections, are dreaded complications of liver transplantation, particularly early after transplant. We describe the case of a patient that presented 6 years after liver transplant with a Lichtheimia corymbifera-infected leg ulcer, following previous COVID-19 infection and moderate rejection requiring steroid pulses. The patient required long-term antifungal therapy, repeated surgical debridement and eventually wound coverage with meshed split-thickness skin graft. Our case illustrates the challenges in the treatment of cutaneous mucormycosis and highlights the difficulties in achieving an accurate balance between the risk of opportunistic infections and rejection in this population.

15.
Front Immunol ; 13: 781364, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35296093

RESUMO

Regulatory T cells (Tregs) are capable of inhibiting the proliferation, activation and function of T cells and play an important role in impeding the immune response to cancer. In chronic lymphocytic leukemia (CLL) a dysfunctional immune response and elevated percentage of effector-like phenotype Tregs have been described. In this study, using the Eµ-TCL1 mouse model of CLL, we evaluated the changes in the Tregs phenotype and their expansion at different stages of leukemia progression. Importantly, we show that Tregs depletion in DEREG mice triggered the expansion of new anti-leukemic cytotoxic T cell clones leading to leukemia eradication. In TCL1 leukemia-bearing mice we identified and characterized a specific Tregs subpopulation, the phenotype of which suggests its role in the formation of an immunosuppressive microenvironment, supportive for leukemia survival and proliferation. This observation was also confirmed by the gene expression profile analysis of these TCL1-specific Tregs. The obtained data on Tregs are consistent with those described so far, however, above all show that the changes in the Tregs phenotype described in CLL result from the formation of a specific, described in this study Tregs subpopulation. In addition, functional tests revealed the ability of Tregs to inhibit T cells that recognize model antigens expressed by leukemic cells. Moreover, inhibition of Tregs with a MALT1 inhibitor provided a therapeutic benefit, both as monotherapy and also when combined with an immune checkpoint inhibitor. Altogether, activation of Tregs appears to be crucial for CLL progression.


Assuntos
Leucemia Linfocítica Crônica de Células B , Animais , Modelos Animais de Doenças , Imunidade , Imunossupressores/uso terapêutico , Camundongos , Linfócitos T Reguladores , Microambiente Tumoral
16.
Cancers (Basel) ; 13(18)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34572746

RESUMO

Chronic lymphocytic leukemia (CLL) is the most frequent leukemia in the elderly and is characterized by the accumulation of mature B lymphocytes in peripheral blood and primary lymphoid organs. In order to proliferate, leukemic cells are highly dependent on complex interactions with their microenvironment in proliferative niches. Not only soluble factors and BCR stimulation are important for their survival and proliferation, but also the activation of transcription factors through different signaling pathways. The aryl hydrocarbon receptor (AHR) and hypoxia-inducible factor (HIF)-1α are two transcription factors crucial for cancer development, whose activities are dependent on tumor microenvironment conditions, such as the presence of metabolites from the tryptophan pathway and hypoxia, respectively. In this study, we addressed the potential role of AHR and HIF-1α in chronic lymphocytic leukemia (CLL) development in vivo. To this end, we crossed the CLL mouse model Eµ-TCL1 with the corresponding transcription factor-conditional knock-out mice to delete one or both transcription factors in CD19+ B cells only. Despite AHR and HIF-1α being activated in CLL cells, deletion of either or both of them had no impact on CLL progression or survival in vivo, suggesting that these transcription factors are not crucial for leukemogenesis in CLL.

17.
Front Immunol ; 11: 578176, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33193376

RESUMO

In the past 20 years, the interest for the tumor microenvironment (TME) has exponentially increased. Indeed, it is now commonly admitted that the TME plays a crucial role in cancer development, maintenance, immune escape and resistance to therapy. This stands true for hematological malignancies as well. A considerable amount of newly developed therapies are directed against the cancer-supporting TME instead of targeting tumor cells themselves. However, the TME is often not clearly defined. In addition, the unique phenotype of each tumor and the variability among patients limit the success of such therapies. Recently, our group took advantage of the mass cytometry technology to unveil the specific TME in the context of chronic lymphocytic leukemia (CLL) in mice. We found the enrichment of LAG3 and PD1, two immune checkpoints. We tested an antibody-based immunotherapy, targeting these two molecules. This combination of antibodies was successful in the treatment of murine CLL. In this methods article, we provide a detailed protocol for the staining of CLL TME cells aiming at their characterization using mass cytometry. We include panel design and validation, sample preparation and acquisition, machine set-up, quality control, and analysis. Additionally, we discuss different advantages and pitfalls of this technique.


Assuntos
Biomarcadores Tumorais/metabolismo , Citometria de Fluxo , Leucemia Linfocítica Crônica de Células B/metabolismo , Microambiente Tumoral , Animais , Antígenos CD/metabolismo , Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/imunologia , Inibidores de Checkpoint Imunológico/farmacologia , Imunoterapia , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/imunologia , Camundongos , Receptor de Morte Celular Programada 1/metabolismo , Proteína do Gene 3 de Ativação de Linfócitos
18.
Cells ; 8(5)2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-31086070

RESUMO

Tumor-infiltrating lymphocytes are known to be critical in controlling tumor progression. While the role of T lymphocytes has been extensively studied, the function of B cells in this context is still ill-defined. In this review, we propose to explore the role of B cells in tumor immunity. First of all we define their dual role in promoting and inhibiting cancer progression depending on their phenotype. To continue, we describe the influence of different tumor microenvironment factors such as hypoxia on B cells functions and differentiation. Finally, the role of B cells in response to therapy and as potential target is examined. In accordance with the importance of B cells in immuno-oncology, we conclude that more studies are required to throw light on the precise role of B cells in the tumor microenvironment in order to have a better understanding of their functions, and to design new strategies that efficiently target these cells by immunotherapy.


Assuntos
Linfócitos B/imunologia , Carcinogênese/imunologia , Neoplasias , Microambiente Tumoral , Animais , Linfócitos B/citologia , Linhagem Celular , Humanos , Imunoterapia , Oncologia , Camundongos , Neoplasias/imunologia , Neoplasias/terapia , Ratos
19.
Pediatr Dent ; 35(2): E49-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23635970

RESUMO

PURPOSE: Advocacy is the primary mission of the American Academy of Pediatric Dentistry (AAPD), but members' participation in advocacy is not well known. The purpose of this study was to examine advocacy by AAPD members and their attitudes toward various advocacy-related activities. METHODS: An Internet-based questionnaire, e-mailed to 4,328 AAPD members via Survey Monkey, consisted of 19 questions on: demography; advocacy training; attitudes toward advocacy; and past, recent, and current advocacy practices. RESULTS: A total of 1,046 respondents provided a 25% response rate. Ninety percent supported advocacy as a role for pediatric dentists. Two-thirds felt prepared for advocacy, but only 22% had training in residency. Participation in clinical advocacy was the most common activity, but most respondents reported local oral health promotion and promotion of oral health with other professionals. Approximately half or fewer reported participation in political action or lobbying. Pediatric dentists out of training longer were more likely to participate in advocacy as were male pediatric dentists. CONCLUSIONS: American Academy of Pediatric Dentistry members support the advocacy role of pediatric dentists and participate in a wide range of advocacy activities.


Assuntos
Defesa da Criança e do Adolescente , Defesa do Paciente , Odontopediatria , Atitude do Pessoal de Saúde , Criança , Estudos Transversais , Educação Continuada em Odontologia , Feminino , Política de Saúde , Promoção da Saúde , Acessibilidade aos Serviços de Saúde , Humanos , Internato e Residência , Manobras Políticas , Masculino , Área Carente de Assistência Médica , Saúde Bucal , Odontopediatria/educação , Política , Papel Profissional , Sociedades Odontológicas , Inquéritos e Questionários , Cuidados de Saúde não Remunerados , Estados Unidos
20.
Artigo em Inglês | MEDLINE | ID: mdl-16831676

RESUMO

OBJECTIVE: Human papillomavirus (HPV) infection has been implicated in the development of high-grade squamous dysplasia and carcinoma of the oral cavity in the absence of other known risk factors such as smoking. HPV-induced oral dysplasia or carcinoma may be a unique tumor entity in terms of biologic behavior and treatment decisions. In detecting such cases, most reported studies have used techniques that are less sensitive than DNA amplification. Recent reports have suggested that overexpression of the p16INK4 protein is a surrogate marker of HPV-induced high-grade dysplasia or carcinoma. However, the correlation between expression of p16INK4 and the presence of HPV DNA as determined by polymerase chain reaction (PCR) amplification has not been previously reported. The purpose of this research was to determine if immunohistochemistry for p16 would serve as a marker of HPV-associated high-grade oral squamous dysplasia. STUDY DESIGN: Archival formalin-fixed, paraffin-embedded tissue sections from 41 cases of high-grade oral squamous dysplasia were randomly selected. Expression of p16INK4 protein was assessed by immunohistochemical analysis (16P04 Neomarkers, Fremont, CA). Strong and diffuse nuclear staining restricted to the dysplastic region in the epithelium was scored as positive for protein expression, whereas focal or weak nuclear or cytoplasmic staining was scored as negative. The presence of HPV was determined by microdissection, DNA extraction, and PCR DNA amplification using elongated primers that align with corresponding sequences of the L1 region of 23 mucosotropic HPV genotypes. The HPV type was determined by direct sequencing of the PCR product. Normal squamous epithelium was used as an internal negative control, and cases of severe cervical high-grade squamous dysplasia were used as a positive control for immunohistochemical staining and PCR. RESULTS: The results of immunohistochemical analysis for overexpression of p16INK4 were positive in 6 of the 41 tissue sections. The results of PCR DNA amplification were also positive for these 6 sections. HPV-16 was identified in 5 of the positive cases; in the other case, the viral strain could not be determined. CONCLUSIONS: Immunohistochemical detection of p16INK4 is a technically simple and potentially reliable assay for diagnosing cases of HPV-induced oral high-grade squamous dysplasia. Detecting such lesions may influence future therapeutic decisions.


Assuntos
Biomarcadores Tumorais , Carcinoma de Células Escamosas/virologia , Inibidor p16 de Quinase Dependente de Ciclina/biossíntese , Papillomavirus Humano 16/patogenicidade , Neoplasias Bucais/virologia , Lesões Pré-Cancerosas/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/etiologia , Sondas de DNA de HPV , DNA Viral/análise , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/enzimologia , Neoplasias Bucais/etiologia , Infecções por Papillomavirus/complicações , Lesões Pré-Cancerosas/enzimologia , Lesões Pré-Cancerosas/etiologia
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