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1.
Blood ; 142(9): 794-805, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37217183

RESUMO

Targeted therapies for cutaneous T-cell lymphoma (CTCL) are limited and curative approaches are lacking. Furthermore, relapses and drug induced side effects are major challenges in the therapeutic management of patients with CTCL, creating an urgent need for new and effective therapies. Pathologic constitutive NF-κB activity leads to apoptosis resistance in CTCL cells and, thus, represents a promising therapeutic target in CTCL. In a preclinical study we showed the potential of dimethyl fumarate (DMF) to block NF-κB and, specifically, kill CTCL cells. To translate these findings to applications in a clinical setting, we performed a multicentric phase 2 study evaluating oral DMF therapy in 25 patients with CTCL stages Ib to IV over 24 weeks (EudraCT number 2014-000924-11/NCT number NCT02546440). End points were safety and efficacy. We evaluated skin involvement (using a modified severity weighted assessment tool [mSWAT]), pruritus, quality of life, and blood involvement, if applicable, as well as translational data. Upon skin analysis, 7 of 23 (30.4%) patients showed a response with >50% reduction in the mSWAT score. Patients with high tumor burden in the skin and blood responded best to DMF therapy. Although not generally significant, DMF also improved pruritus in several patients. Response in the blood was mixed, but we confirmed the NF-κB-inhibiting mechanism of DMF in the blood. The overall tolerability of the DMF therapy was very favorable, with mostly mild side effects. In conclusion, our study presents DMF as an effective and excellently tolerable therapeutic option in CTCL to be further evaluated in a phase 3 study or real-life patient care as well as in combination therapies. This trial was registered at www.clinicaltrials.gov as #NCT02546440.


Assuntos
Linfoma Cutâneo de Células T , Neoplasias Cutâneas , Humanos , Fumarato de Dimetilo/uso terapêutico , NF-kappa B , Qualidade de Vida , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Linfoma Cutâneo de Células T/tratamento farmacológico , Linfoma Cutâneo de Células T/patologia , Prurido/tratamento farmacológico
2.
Int J Mol Sci ; 25(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38892300

RESUMO

Reactive oxygen species (ROS) are central to inter- and intracellular signaling. Their localized and transient effects are due to their short half-life, especially when generated in controlled amounts. Upon T cell receptor (TCR) activation, regulated ROS signaling is primarily initiated by complexes I and III of the electron transport chain (ETC). Subsequent ROS production triggers the activation of nicotinamide adenine dinucleotide phosphate oxidase 2 (NADPH oxidase 2), prolonging the oxidative signal. This signal then engages kinase signaling cascades such as the mitogen-activated protein kinase (MAPK) pathway and increases the activity of REDOX-sensitive transcription factors such as nuclear factor-kappa B (NF-κB) and activator protein-1 (AP-1). To limit ROS overproduction and prevent oxidative stress, nuclear factor erythroid 2-related factor 2 (Nrf2) and antioxidant proteins such as superoxide dismutases (SODs) finely regulate signal intensity and are capable of terminating the oxidative signal when needed. Thus, oxidative signals, such as T cell activation, are well-controlled and critical for cellular communication.


Assuntos
Espécies Reativas de Oxigênio , Transdução de Sinais , Linfócitos T , Espécies Reativas de Oxigênio/metabolismo , Humanos , Linfócitos T/metabolismo , Linfócitos T/imunologia , Animais , Ativação Linfocitária , Estresse Oxidativo , Oxirredução , Receptores de Antígenos de Linfócitos T/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo
3.
BMC Gastroenterol ; 23(1): 180, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37226088

RESUMO

BACKGROUND: Partial splenic embolization (PSE) is a non-surgical procedure which was initially used to treat hypersplenism. Furthermore, partial splenic embolization can be used for the treatment of different conditions, including gastroesophageal variceal hemorrhage. Here, we evaluated the safety and efficacy of emergency and non-emergency PSE in patients with gastroesophageal variceal hemorrhage and recurrent portal hypertensive gastropathy bleeding due to cirrhotic (CPH) and non-cirrhotic portal hypertension (NCPH). METHODS: From December 2014 to July 2022, twenty-five patients with persistent esophageal variceal hemorrhage (EVH) and gastric variceal hemorrhage (GVH), recurrent EVH and GVH, controlled EVH with a high risk of recurrent bleeding, controlled GVH with a high risk of rebleeding, and portal hypertensive gastropathy due to CPH and NCPH underwent emergency and non-emergency PSE. PSE for treatment of persistent EVH and GVH was defined as emergency PSE. In all patients pharmacological and endoscopic treatment alone had not been sufficient to control variceal bleeding, and the placement of a transjugular intrahepatic portosystemic shunt (TIPS) was contraindicated, not reasonable due to portal hemodynamics, or TIPS failure with recurrent esophageal bleeding had occurred. The patients were followed-up for six months. RESULTS: All twenty-five patients, 12 with CPH and 13 with NCPH were successfully treated with PSE. In 13 out of 25 (52%) patients, PSE was performed under emergency conditions due to persistent EVH and GVH, clearly stopping the bleeding. Follow-up gastroscopy showed a significant regression of esophageal and gastric varices, classified as grade II or lower according to Paquet's classification after PSE in comparison to grade III to IV before PSE. During the follow-up period, no variceal re-bleeding occurred, neither in patients who were treated under emergency conditions nor in patients with non-emergency PSE. Furthermore, platelet count increased starting from day one after PSE, and after one week, thrombocyte levels had improved significantly. After six months, there was a sustained increase in the thrombocyte count at significantly higher levels. Fever, abdominal pain, and an increase in leucocyte count were transient side effects of the procedure. Severe complications were not observed. CONCLUSION: This is the first study analyzing the efficacy of emergency and non-emergency PSE for the treatment of gastroesophageal hemorrhage and recurrent portal hypertensive gastropathy bleeding in patients with CPH and NCPH. We show that PSE is a successful rescue therapy for patients in whom pharmacological and endoscopic treatment options fail and the placement of a TIPS is contraindicated. In critically ill CPH and NCPH patients with fulminant gastroesophageal variceal bleeding, PSE showed good results and is therefore an effective tool for the rescue and emergency management of gastroesophageal hemorrhage.


Assuntos
Embolização Terapêutica , Varizes Esofágicas e Gástricas , Hipertensão Portal , Humanos , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/terapia , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Tratamento de Emergência , Hipertensão Portal/complicações
4.
Dig Dis ; 41(4): 647-655, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36871551

RESUMO

BACKGROUND: Acute severe pancreatitis is associated with high morbidity and mortality. Hypertriglyceridemia is the third most common cause of acute pancreatitis and higher triglyceride levels increase the risk for severe acute pancreatitis. Plasma exchange is an effective treatment method to lower triglycerides. Our study aimed to investigate the efficiency of plasma exchange as a treatment option for acute hypertriglyceridemia-induced pancreatitis (HTGP), the impact on mortality assessed by the SOFA, SAPS II, BISAP Score, Ranson's, and Glasgow-Imrie Criteria, as well as the overall length of stay in hospital and ICU. METHODS: In this retrospective single-center cohort study, triglycerides before and after plasma exchange were compared. SOFA and SAPS II were taken on ICU admission and at discharge. To further characterize the patient cohort, BISAP Score (on admission), Ranson's Criteria (on admission and after 48 h), and the Glasgow-Imrie Criteria (48 h after admission) were calculated. RESULTS: The study included 11 patients (91% male; median age 45 years). Triglycerides were reduced from 4,266 ± 3,560.6 to 842 ± 575.9 mg/dL during plasmapheresis (p < 0.001). The median ICU length of stay was 3 ± 4.2 days. In-hospital mortality was 0%. The SOFA score was significantly reduced from 4 ± 3.4 points on admission to 2 ± 2.1 points at discharge (p = 0.017). Triglycerides and cholesterol decreased from 3,126 ± 3,665 to 531 ± 273 mg/dL (p = 0.003) and from 438 ± 137.9 to 222 ± 59.5 mg/dL (p = 0.028), respectively. The BISAP Score on admission was 3 ± 0.5 points, Ranson's Criteria were 3 ± 1.5 points (48 h after admission, cumulative), and Glasgow-Imrie Criteria 3 ± 1.3 points (48 h after admission). CONCLUSION: Plasmapheresis is an efficient and safe treatment method for ICU patients with acute HTGP and significantly reduces triglycerides. Furthermore, plasmapheresis significantly improves the clinical outcomes of patients with HTGP.


Assuntos
Hipertrigliceridemia , Pancreatite , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Pancreatite/etiologia , Pancreatite/terapia , Troca Plasmática/efeitos adversos , Estudos de Coortes , Estudos Retrospectivos , Doença Aguda , Plasmaferese/efeitos adversos , Hipertrigliceridemia/complicações , Hipertrigliceridemia/terapia , Triglicerídeos , Unidades de Terapia Intensiva
5.
Gut ; 71(3): 580-592, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33707230

RESUMO

OBJECTIVE: Spontaneous bacterial peritonitis (SBP) is a life-threatening complication of liver cirrhosis with a 1-year mortality of 66%. Bacterial translocation (BT) from the intestine to the mesenteric lymph nodes is crucial for the pathogenesis of SBP. DESIGN: Since BT presupposes a leaky intestinal epithelium, the integrity of mucus and epithelial cell junctions (E-cadherin and occludin) was examined in colonic biopsies from patients with liver cirrhosis and controls. SBP-inducing Escherichia coli (E. coli) and Proteus mirabilis (P. mirabilis) were isolated from ascites of patients with liver cirrhosis and co-cultured with Caco-2 cells to characterise bacteria-to-cell effects. RESULTS: SBP-derived E. coli and P. mirabilis led to a marked reduction of cell-to-cell junctions in a dose-dependent and time-dependent manner. This effect was enhanced by a direct interaction of live bacteria with epithelial cells. Degradation of occludin is mediated via increased ubiquitination by the proteasome. Remarkably, a novel bacterial protease activity is of pivotal importance for the cleavage of E-cadherin. CONCLUSION: Patients with liver cirrhosis show a reduced thickness of colonic mucus, which allows bacteria-to-epithelial cell contact. Intestinal bacteria induce degradation of occludin by exploiting the proteasome of epithelial cells. We identified a novel bacterial protease activity of patient-derived SBP-inducing bacteria, which is responsible for the cleavage of E-cadherin structures. Inhibition of this protease activity leads to stabilisation of cell junctions. Thus, targeting these mechanisms by blocking the ubiquitin-proteasome system and/or the bacterial protease activity might interfere with BT and constitute a novel innovative therapeutic strategy to prevent SBP in patients with liver cirrhosis.


Assuntos
Ascite/microbiologia , Translocação Bacteriana/fisiologia , Escherichia coli/fisiologia , Cirrose Hepática/complicações , Peritonite/etiologia , Proteus mirabilis/fisiologia , Células CACO-2 , Caderinas/metabolismo , Estudos de Casos e Controles , Técnicas de Cocultura , Colo/microbiologia , Colo/patologia , Feminino , Humanos , Junções Intercelulares , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Ocludina/metabolismo , Peptídeo Hidrolases , Peritonite/metabolismo
6.
Blood ; 134(5): 445-455, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31167801

RESUMO

Therapeutic options for cutaneous T-cell lymphoma (CTCL) are limited and curative treatment regimens are not available. Thus, new targeted and well-tolerated therapeutic approaches are urgently needed. In this respect, we have recently shown that dimethyl fumerate (DMF) inhibits NF-κB acting as a survival factor in CTCL. Similarly, inhibition of the antiapoptotic protein B-cell lymphoma 2 (Bcl-2) has been shown to induce cell death in CTCL especially when combined with histone deacetylase inhibitors. Therefore, we hypothesized that inhibition of Bcl-2 should potentiate NF-κB inhibition in a novel combination treatment of CTCL. We show that, in vitro, the Bcl-2 inhibitors ABT-199 and ABT-263 induced specific cell death in primary CD4+ cells from CTCL patients as well as in the CTCL cell line SeAx, but not in T cells of healthy donors nor in the CTCL cell line HH, which lacks Bcl-2. Combined treatment with ABT-199 and DMF caused synergistic cell death specifically in CTCL cells engaging 2 independent signaling pathways. To verify these findings in vivo, we performed combined ABT-199 and DMF treatment in a xenograft mouse model for CTCL. The combined treatment effectively reduced tumor growth and increased overall survival via synergistic induction of CTCL cell death and suppression of tumor cell proliferation. Essentially, the combination treatment was superior to ABT-199 monotherapy with respect to both efficacy and tolerability. To sum up, our data provide proof of principle for the therapeutic potential of combining Bcl-2 and NF-κB inhibitors in treating CTCL. Next, this potential should be explored further in a clinical study.


Assuntos
Antineoplásicos/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Linfoma Cutâneo de Células T/metabolismo , NF-kappa B/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Animais , Apoptose , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos , Linfoma Cutâneo de Células T/diagnóstico , Linfoma Cutâneo de Células T/tratamento farmacológico , Linfoma Cutâneo de Células T/genética , Camundongos , NF-kappa B/genética , Estadiamento de Neoplasias , Ligação Proteica , Proteínas Proto-Oncogênicas c-bcl-2/genética , Interferência de RNA , RNA Interferente Pequeno/genética , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Blood ; 128(6): 805-15, 2016 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-27268084

RESUMO

Despite intensive efforts in recent years, a curative therapy for cutaneous T-cell lymphoma (CTCL) has not yet been developed. Therefore, the establishment of new therapeutic approaches with higher efficacy rates and milder side effects is strongly desired. A characteristic feature of the malignant T-cell population in CTCL is resistance toward cell death resulting from constitutive NF-κB activation. Therefore, NF-κB-dependent cell death resistance represents an interesting therapeutic target in CTCL because an NF-κB-directed therapy would leave bystander T cells widely unaffected. We investigated the effects of dimethyl fumarate (DMF) on CTCL cells in vitro and in vivo. DMF induced cell death in primary patient-derived CD4(+) cells and CTCL cell lines, but hardly in T cells from healthy donors. DMF-induced cell death was linked specifically to NF-κB inhibition. To study the impact of DMF in vivo, we developed 2 CTCL xenograft mouse models with different cutaneous localizations of the T-cell infiltrate. DMF treatment delayed the growth of CTCL tumors and prevented formation of distant metastases. In addition, DMF induced increased cell death in primary CTCL tumors and in liver metastases. In summary, DMF treatment represents a remarkable therapeutic option in CTCL because it restores CTCL apoptosis in vitro and in preclinical models in vivo and prevents spreading of the disease to distant sites. DMF treatment is of particular promise in CTCL because DMF is already in successful clinical use in the treatment of psoriasis and multiple sclerosis allowing fast translation into clinical studies in CTCL.


Assuntos
Apoptose/efeitos dos fármacos , Fumarato de Dimetilo/uso terapêutico , Imunossupressores/uso terapêutico , Linfoma Cutâneo de Células T/tratamento farmacológico , NF-kappa B/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Pele/efeitos dos fármacos , Animais , Humanos , Linfoma Cutâneo de Células T/imunologia , Linfoma Cutâneo de Células T/patologia , Camundongos , NF-kappa B/imunologia , Metástase Neoplásica/imunologia , Metástase Neoplásica/patologia , Metástase Neoplásica/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Pele/imunologia , Pele/patologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Células Tumorais Cultivadas
8.
Cancers (Basel) ; 16(10)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38791911

RESUMO

We conducted a comprehensive review of the current literature of published data and clinical trials (MEDLINE), as well as published congress contributions and active recruiting clinical trials on targeted therapies in hepatocellular carcinoma. Combinations of different agents and medical therapy along with radiological interventions were analyzed for the setting of advanced HCC. Those settings were also analyzed in combination with adjuvant situations after resection or radiological treatments. We summarized the current knowledge for each therapeutic setting and combination that currently is or has been under clinical evaluation. We further discuss the results in the background of current treatment guidelines. In addition, we review the pathophysiological mechanisms and pathways for each of these investigated targets and drugs to further elucidate the molecular background and underlying mechanisms of action. Established and recommended targeted treatment options that already exist for patients are considered for systemic treatment: atezolizumab/bevacizumab, durvalumab/tremelimumab, sorafenib, lenvatinib, cabozantinib, regorafenib, and ramucirumab. Combination treatment for systemic treatment and local ablative treatment or transarterial chemoembolization and adjuvant and neoadjuvant treatment strategies are under clinical investigation.

9.
Cancers (Basel) ; 16(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38730642

RESUMO

We conducted a comprehensive review of the current literature of published data, clinical trials (MEDLINE; ncbi.pubmed.com), congress contributions (asco.org; esmo.org), and active recruiting clinical trains (clinicaltrial.gov) on targeted therapies in cholangiocarcinoma. Palliative treatment regimens were analyzed as well as preoperative and perioperative treatment options. We summarized the current knowledge for each mutation and molecular pathway that is or has been under clinical evaluation and discussed the results on the background of current treatment guidelines. We established and recommended targeted treatment options that already exist for second-line settings, including IDH-, BRAF-, and NTRK-mutated tumors, as well as for FGFR2 fusion, HER2/neu-overexpression, and microsatellite instable tumors. Other options for targeted treatment include EGFR- or VEGF-dependent pathways, which are known to be overexpressed or dysregulated in this cancer type and are currently under clinical investigation. Targeted therapy in CCA is a hallmark of individualized medicine as these therapies aim to specifically block pathways that promote cancer cell growth and survival, leading to tumor shrinkage and improved patient outcomes based on the molecular profile of the tumor.

10.
J Gastrointestin Liver Dis ; 33(2): 194-202, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38944869

RESUMO

BACKGROUND AND AIMS: Ultra-microangiography (UMA) is a novel Doppler technique with optimized wall filtering that provides high sensitivity to low-velocity blood flows and optimized visualization of microcirculation. The aim of this pilot study was to compare intestinal vascularization assessed by color Doppler signals (CDS) and UMA. METHODS: We investigated intestinal vascularization using UMA and CDS in 13 patients with confirmed inflammatory bowel disease (IBD). A cohort of 28 patients without structural bowel disease served as the control. RESULTS: Microcirculation and dysregulated microcirculation in patients without and with inflammatory bowel disease can be visualized and quantified using UMA. In 83 % of IBD patients and 76% of non-IBD patients, a high resolution of intestinal perfusion could be achieved using UMA. CONCLUSIONS: To the best of our knowledge, this is the first study to investigate intestinal vascularization using UMA in patients with and without structural bowel disease. Quantification and visualization of intestinal vascularization should be further investigated in prospective studies and could help guide our therapy of patients with IBD.


Assuntos
Intestinos , Microcirculação , Humanos , Projetos Piloto , Microcirculação/fisiologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Intestinos/irrigação sanguínea , Intestinos/diagnóstico por imagem , Doenças Inflamatórias Intestinais/diagnóstico por imagem , Doenças Inflamatórias Intestinais/fisiopatologia , Ultrassonografia Doppler em Cores , Angiografia/métodos , Idoso , Adulto Jovem , Valor Preditivo dos Testes , Estudos de Casos e Controles
11.
Front Med (Lausanne) ; 11: 1292608, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38660424

RESUMO

Background: Since the onset of the COVID-19 pandemic, global healthcare systems have faced unprecedented challenges, leading to significant psychological distress among healthcare professionals. Recognizing the importance of enhanced interprofessional collaboration in alleviating this burden, as emphasized by the World Health Organization in 2020, we investigated whether such collaboration could mitigate staff psychological distress during crises. To our knowledge, no study has yet explored the role of interprofessional collaboration as a resilience factor in crises. Methods: For this monocentric cross-sectional study at a German university hospital, we examined the relationship between the quality of interprofessional collaboration and the psychological distress of healthcare professionals during the initial pandemic wave. We employed validated mental health instruments, such as the GAD-7 and PHQ-2, to assess anxiety and depressive symptoms. Additionally, custom-designed questionnaires evaluated "Pandemic-Associated Burden and Anxiety (PAB; PAA)" and interprofessional crisis management experiences. A novel "Interprofessional collaboration and communication (IPC)" assessment tool was developed based on international competency frameworks, demonstrating strong reliability. Results: The study involved 299 healthcare professionals (78.6% in direct contact with COVID-19 patients). Moderate levels of PAB/PAA were reported. However, a significant proportion experienced clinically relevant anxiety, as indicated by GAD-7. Negative IPC perceptions correlated with higher levels of psychological distress. Linear regression analysis showed associations between interprofessional collaboration and anxious and depressive symptoms, and pandemic-related burden. Conclusion: Our findings highlight the vital role of enhanced interprofessional collaboration in strengthening the psychological well-being of healthcare professionals during crises. The study underscores the need to foster a collaborative environment and integrate interprofessional education for resilience.

12.
Front Med (Lausanne) ; 11: 1334865, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895187

RESUMO

Intoduction: Identification of specific metabolome and lipidome profile of patients with primary sclerosing cholangitis (PSC) is crucial for diagnosis, targeted personalized therapy, and more accurate risk stratification. Methods: Nuclear magnetic resonance (NMR) spectroscopy revealed an altered metabolome and lipidome of 33 patients with PSC [24 patients with inflammatory bowel disease (IBD) and 9 patients without IBD] compared with 40 age-, sex-, and body mass index (BMI)-matched healthy controls (HC) as well as 64 patients with IBD and other extraintestinal manifestations (EIM) but without PSC. Results: In particular, higher concentrations of pyruvic acid and several lipoprotein subfractions were measured in PSC in comparison to HC. Of clinical relevance, a specific amino acid and lipid profile was determined in PSC compared with IBD and other EIM. Discussion: These results have the potential to improve diagnosis by differentiating PSC patients from HC and those with IBD and EIM.

13.
Biochim Biophys Acta ; 1823(5): 1041-52, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22429591

RESUMO

Mitochondrial reactive oxygen species (ROS) are indispensible for T cell activation-induced expression of interleukin 2 (IL-2) and CD95 ligand (CD95L, FasL/Apo-1L) genes, and in turn, for CD95L-mediated activation-induced cell death (AICD). Here, we show that manganese superoxide dismutase (MnSOD/SOD2), a major mitochondrial antioxidative enzyme, constitutes an important control switch in the process of activation-induced oxidative signal generation in T cells. Analysis of the kinetics of T cell receptor (TCR)-triggered ROS production revealed a temporal association between higher MnSOD abundance/activity and a shut-down phase of oxidative signal generation. Transient or inducible MnSOD overexpression abrogated T cell activation-triggered mitochondrial ROS production as well as NF-κB- and AP-1-mediated transcription. Consequently, lowered expression of IL-2 and CD95L genes resulted in decreased IL-2 secretion and CD95L-dependent AICD. Moreover, upregulation of the mitochondrial MnSOD level is dependent on oxidation-sensitive transcription and not on the increase of mitochondrial mass. Thus, MnSOD-mediated negative feedback regulation of activation-induced mitochondrial ROS generation exemplifies a process of retrograde mitochondria-to-nucleus communication. Our finding underlines the critical role for MnSOD and mitochondria in the regulation of human T cell activation.


Assuntos
Ativação Linfocitária/imunologia , Transdução de Sinais/imunologia , Superóxido Dismutase/metabolismo , Linfócitos T/citologia , Linfócitos T/enzimologia , Morte Celular/imunologia , Proteína Ligante Fas/metabolismo , Regulação da Expressão Gênica , Humanos , Células Jurkat , Mitocôndrias/metabolismo , Modelos Imunológicos , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Linfócitos T/imunologia , Transcrição Gênica
14.
Blood ; 117(8): 2433-40, 2011 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-21209378

RESUMO

Cutaneous T-cell lymphomas (CTCLs) are malignancies of skin-homing lymphoid cells, which have so far not been investigated thoroughly for common oncogenic mutations. We screened 90 biopsy specimens from CTCL patients (41 mycosis fungoides, 36 Sézary syndrome, and 13 non-mycosis fungoides/Sézary syndrome CTCL) for somatic mutations using OncoMap technology. We detected oncogenic mutations for the RAS pathway in 4 of 90 samples. One mycosis fungoides and one pleomorphic CTCL harbored a KRAS(G13D) mutation; one Sézary syndrome and one CD30(+) CTCL harbored a NRAS(Q61K) amino acid change. All mutations were found in stage IV patients (4 of 42) who showed significantly decreased overall survival compared with stage IV patients without mutations (P = .04). In addition, we detected a NRAS(Q61K) mutation in the CTCL cell line Hut78. Knockdown of NRAS by siRNA induced apoptosis in mutant Hut78 cells but not in CTCL cell lines lacking RAS mutations. The NRAS(Q61K) mutation sensitized Hut78 cells toward growth inhibition by the MEK inhibitors U0126, AZD6244, and PD0325901. Furthermore, we found that MEK inhibitors exclusively induce apoptosis in Hut78 cells. Taken together, we conclude that RAS mutations are rare events at a late stage of CTCL, and our preclinical results suggest that such late-stage patients profit from MEK inhibitors.


Assuntos
Ensaios de Triagem em Larga Escala/métodos , Linfoma Cutâneo de Células T/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas/genética , Transdução de Sinais/genética , Quinases raf/metabolismo , Proteínas ras/metabolismo , Biópsia , Humanos , Linfoma Cutâneo de Células T/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Micose Fungoide , Estadiamento de Neoplasias , Inibidores de Proteínas Quinases/farmacologia , Síndrome de Sézary , Transdução de Sinais/efeitos dos fármacos , Proteínas ras/genética
15.
Cancers (Basel) ; 15(22)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38001650

RESUMO

p53, a crucial tumor suppressor and transcription factor, plays a central role in the maintenance of genomic stability and the orchestration of cellular responses such as apoptosis, cell cycle arrest, and DNA repair in the face of various stresses. Sestrins, a group of evolutionarily conserved proteins, serve as pivotal mediators connecting p53 to kinase-regulated anti-stress responses, with Sestrin 2 being the most extensively studied member of this protein family. These responses involve the downregulation of cell proliferation, adaptation to shifts in nutrient availability, enhancement of antioxidant defenses, promotion of autophagy/mitophagy, and the clearing of misfolded proteins. Inhibition of the mTORC1 complex by Sestrins reduces cellular proliferation, while Sestrin-dependent activation of AMP-activated kinase (AMPK) and mTORC2 supports metabolic adaptation. Furthermore, Sestrin-induced AMPK and Unc-51-like protein kinase 1 (ULK1) activation regulates autophagy/mitophagy, facilitating the removal of damaged organelles. Moreover, AMPK and ULK1 are involved in adaptation to changing metabolic conditions. ULK1 stabilizes nuclear factor erythroid 2-related factor 2 (Nrf2), thereby activating antioxidative defenses. An understanding of the intricate network involving p53, Sestrins, and kinases holds significant potential for targeted therapeutic interventions, particularly in pathologies like cancer, where the regulatory pathways governed by p53 are often disrupted.

16.
Biomedicines ; 11(5)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37239059

RESUMO

The human gastrointestinal tract is home to a complex microbial community that plays an important role in the general well-being of the entire organism. The gut microbiota generates a variety of metabolites and thereby regulates many biological processes, such as the regulation of the immune system. In the gut, bacteria are in direct contact with the host. The major challenge here is to prevent unwanted inflammatory reactions on one hand and on the other hand to ensure that the immune system can be activated when pathogens invade. Here the REDOX equilibrium is of utmost importance. This REDOX equilibrium is controlled by the microbiota either directly or indirectly via bacterial-derived metabolites. A balanced microbiome sorts for a stable REDOX balance, whereas dysbiosis destabilizes this equilibrium. An imbalanced REDOX status directly affects the immune system by disrupting intracellular signaling and promoting inflammatory responses. Here we (i) focus on the most common reactive oxygen species (ROS) and (ii) define the transition from a balanced REDOX state to oxidative stress. Further, we (iii) describe the role of ROS in regulating the immune system and inflammatory responses. Thereafter, we (iv) examine the influence of microbiota on REDOX homeostasis and how shifts in pro- and anti-oxidative cellular conditions can suppress or promote immune responses or inflammation.

17.
Drugs R D ; 23(2): 93-98, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36988798

RESUMO

BACKGROUND AND OBJECTIVE: Metamizole is a non-opioid ampyrone sulfonate compound with potent analgesic, antipyretic, and spasmolytic effects. Agranulocytosis is a rare life-threatening complication of metamizole. CASE: Here, we present the case of a 62-year-old patient who developed agranulocytosis as well as hemolysis after a single administration of metamizole. CONCLUSION: This case illustrates the inherent allergic potential of metamizole and its effects on different hematopoietic cell types.


Assuntos
Agranulocitose , Neutropenia , Humanos , Pessoa de Meia-Idade , Dipirona/efeitos adversos , Anti-Inflamatórios não Esteroides/efeitos adversos , Hemólise , Agranulocitose/induzido quimicamente
18.
Biomedicines ; 11(6)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37371761

RESUMO

Despite the recent approval of new therapies, the prognosis for patients with hepatocellular carcinoma (HCC) remains poor. There is a clinical need for new highly effective therapeutic options. Here, we present a combined application of BH3-mimetics as a potential new treatment option for HCC. BH3-mimetics inhibit anti-apoptotic proteins of the BCL-2 family and, thus, trigger the intrinsic apoptosis pathway. Anti-apoptotic BCL-2 proteins such as Bcl-2 and Mcl-1 are frequently overexpressed in HCC. Therefore, we analyzed the efficacy of the two BH3-mimetics ABT-199 (Bcl-2 inhibitor) and MIK665 (Mcl-1 inhibitor) in HCC cell lines with differential expression levels of endogenous Bcl-2 and Mcl-1. While administration of one BH3-mimetic alone did not substantially trigger cell death, the combination of two inhibitors enhanced induction of the intrinsic apoptosis pathway. Both drugs acted synergistically, highlighting the effectivity of this specific BH3-mimetic combination, particularly in HCC cell lines. These results indicate the potential of combining inhibitors of the BCL-2 family as new therapeutic options in HCC.

19.
J Gastrointestin Liver Dis ; 32(3): 346-355, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37774228

RESUMO

BACKGROUND: p53 deletion and mutation as well as upregulation of alpha-fetoprotein (AFP) are hallmarks of hepatocarcinogenesis. p63 and p73 belong to the family of p53-related transcription factors expressing a variety of isoforms. The expression of dominant negative (ΔN) p73 is related to the reduced survival of patients with hepatocellular carcinoma (HCC). In this study, we characterized the interaction between p53 family-dependent signaling pathways and the regulation of AFP at the gene and protein levels as essential determinants of therapeutic response and prognosis in HCC. METHODS: Putative p53-, p63- and p73-binding sites within the AFP gene were identified in silico. Hep3B cells were transfected with plasmids encoding for p53, p63 and p73 to analyze the interplay of the p53 family with AFP. AFP transcription was determined by RT-qPCR. Protein levels of AFP, p53, p63 and p73 were analyzed by Western blot. RESULTS: Underlining the importance of the crosstalk between the p53 family-dependent pathways and AFP regulation we identified eight novel putative binding sites for the members of the p53 family within the introns 1, 2, 3, 4, 7, 8, 11, and 12 of the AFP gene. Accordingly, full-length isoforms of p53, p63 and p73 efficiently downregulated AFP both on mRNA and protein level. Thus, the p53 family members were identified to be major regulators of AFP repression. Of note, p63 was characterized as a novel and p73 as the most efficient repressor of AFP. CONCLUSION: p53 mutation and upregulation of AFP are essential oncogenic events in the development of HCC. Here we show that AFP gene regulation occurs via a combined action of the p53 family members p53, p63 and p73. All three tumor suppressors reduce AFP gene and protein expression. Thus, our findings reveal a novel interaction of p53 family-dependent signaling pathways and AFP regulation at the gene and protein levels in HCC.

20.
Inflamm Bowel Dis ; 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38156773

RESUMO

BACKGROUND: Accurate biomarkers for disease activity and progression in patients with inflammatory bowel disease (IBD) are a prerequisite for individual disease characterization and personalized therapy. We show that metabolic profiling of serum from IBD patients is a promising approach to establish biomarkers. The aim of this work was to characterize metabolomic and lipidomic serum profiles of IBD patients in order to identify metabolic fingerprints unique to the disease. METHODS: Serum samples were obtained from 55 patients with Crohn's disease (CD), 34 patients with ulcerative colitis (UC), and 40 healthy control (HC) individuals and analyzed using proton nuclear magnetic resonance spectroscopy. Classification of patients and HC individuals was achieved by orthogonal partial least squares discriminant analysis and univariate analysis approaches. Disease activity was assessed using the Gastrointestinal Symptom Rating Scale. RESULTS: Serum metabolome significantly differed between CD patients, UC patients, and HC individuals. The metabolomic differences of UC and CD patients compared with HC individuals were more pronounced than the differences between UC and CD patients. Differences in serum levels of pyruvic acid, histidine, and the branched-chain amino acids leucine and valine were detected. The size of low-density lipoprotein particles shifted from large to small dense particles in patients with CD. Of note, apolipoprotein A1 and A2 serum levels were decreased in CD and UC patients with higher fecal calprotectin levels. The Gastrointestinal Symptom Rating Scale is negatively associated with the concentration of apolipoprotein A2. CONCLUSIONS: Metabolomic assessment of serum samples facilitated the differentiation of IBD patients and HC individuals. These differences were constituted by changes in amino acid and lipoprotein levels. Furthermore, disease activity in IBD patients was associated with decreased levels of the atheroprotective apolipoproteins A1 and A2.


The metabolic and lipidomic serum profile of patients with inflammatory bowel disease was analyzed using proton nuclear magnetic resonance spectroscopy. A significantly altered profile in comparison with healthy control individuals was identified, characterized by more atherogenic properties.

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