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1.
Ann Hematol ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967662

RESUMO

Development of Janus-kinase (JAK) inhibitors has revolutionized the therapeutic landscape for patients with myeloproliferative neoplasia (MPN). Following approval of the first JAK1/2-inhibitor Ruxolitinib, symptoms of this inflammatory disease, characterized by splenomegaly, release of inflammatory cytokines and appearance of thrombosis, could be effectively reduced for the first time. However, JAK-inhibitor treatment is limited in several aspects: 1) duration of response: 3 years after initiation of therapy more than 50% of patients have discontinued JAK-inhibitor treatment due to lack of efficacy or resistance; 2) reduction of disease burden: while effective in reducing inflammation and constitutional symptoms, JAK-inhibitors fail to reduce the malignant clone in the majority of patients and therefore lack long-term efficacy. Early clinical trials for patients with myelofibrosis (MF) have tried to address these issues for patients with suboptimal response to Ruxolitinib therapy while combination therapies with Fedratinib are rare. Recent reports provided first evidence on how the JAK2-V617F mutated myeloid cells may influence T-cell responses. JAK2-V617F promoted the synthesis of PD-L1 in MPN cells leading to limited anti-neoplastic T-cell responses, metabolic changes in T-cells and eventually JAK2-V617F-driven immune-escape of MPN cells. These findings may facilitate the use of immunotherapeutic approaches for JAK-mutated clones. Immune checkpoints refer to a variety of inhibitory pathways that are crucial for maintaining self-tolerance and modulating the duration and amplitude of physiological immune responses in peripheral tissues in order to minimize collateral tissue damage. The FRACTION study is a single arm, open label Phase II trial investigating the combination of Fedratinib with the PD-1 inhibitor Nivolumab in patients with myelofibrosis and suboptimal or lack of response to JAK-inhibitor therapy. Over a 12 months period the trial assesses longer term outcomes, particularly the effects on clinical outcomes, such as induction of clinical remissions, quality of life and improvement of anemia. No prospective clinical trial data exist for combinations of JAK- and immune-checkpoint-inhibitors in the planned MF study population and this study will provide new findings that may contribute to advancing the treatment landscape for MF patients with suboptimal responses and limited alternatives.

2.
Clin Lung Cancer ; 22(2): 142-146, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33158765

RESUMO

BACKGROUND: In selected patients with early-stage malignant pleural mesothelioma (MPM), a multimodal therapy that includes surgical cytoreduction, chemotherapy, and/or radiotherapy is recommended. Several clinical trials have demonstrated the beneficial effects of immune checkpoint inhibitors in pretreated MPM patients with advanced disease. Recent clinical data have suggested that the combination of chemotherapy and checkpoint inhibition might improve efficacy. TRIAL DESIGN: The NICITA (nivolumab with chemotherapy in pleural mesothelioma after surgery) trial is a prospective, 1:1 randomized, open-label, multicenter phase II clinical trial (ClinicalTrials.gov identifier, NCT04177953). Ninety-two patients with MPM epithelioid subtype, who had undergone extended pleurectomy and decortication with or without hyperthermic intrathoracic chemoperfusion, will be included to receive adjuvant treatment. All patients will receive ≤ 4 cycles of platinum-based chemotherapy with pemetrexed (arms A and B). Patients in arm B will additionally receive nivolumab, together with the adjuvant chemotherapy, and subsequently for ≤ 12 cycles as maintenance therapy. The primary endpoint of this study is the time-to-next-treatment. The secondary endpoints include progression-free survival, overall survival, proportion of patients with treatment beyond progression, duration of treatment beyond progression in this population, and quality of life. CONCLUSION: This prospective trial will contribute data to assess the efficacy of standard chemotherapy combined with nivolumab in the context of multimodal management of early-stage MPM. The study is currently enrolling patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Mesotelioma Maligno/tratamento farmacológico , Nivolumabe/uso terapêutico , Neoplasias Pleurais/tratamento farmacológico , Quimioterapia Adjuvante , Terapia Combinada , Humanos , Imunoterapia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Quimioterapia de Manutenção , Mesotelioma Maligno/patologia , Mesotelioma Maligno/cirurgia , Neoplasias Pleurais/patologia , Neoplasias Pleurais/cirurgia , Pneumonectomia , Intervalo Livre de Progressão , Estudos Prospectivos , Distribuição Aleatória
3.
Mol Nutr Food Res ; 63(23): e1900133, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31535460

RESUMO

SCOPE: Increasing the intake of satiety-enhancing food compounds represents a promising strategy for maintaining a healthy body weight. Recently, satiating effects for the capsaicinoid nonivamide have been demonstrated. As various proteins and amino acids have also been demonstrated to decrease energy intake, oral glucose tolerance test (oGTT)-based bolus interventions of 75 g glucose + 0.15 mg nonivamide (NV control) are tested with/without combination of a wheat protein hydrolysate (WPH: 2 g) and/or l-arginine (ARG: 3.2 g) for their satiating effects in 27 moderately overweight male subjects. METHODS AND RESULTS: Compared to NV control intervention, ARG and WPH + ARG treatment both reduce (p < 0.01) total calorie intake from a standardized breakfast by -5.9 ± 4.15% and -6.07 ± 4.38%, respectively. For the WPH + ARG intervention, increased mean plasma serotonin concentrations (AUC: 350 ± 218), quantitated by ELISA, and delayed gastric emptying, assessed by 13 C-Na-acetate breath test (-2.10 ± 0.51%, p < 0.05), are demonstrated compared to NV control. Correlation analysis between plasma serotonin and gastric emptying reveals a significant association after WPH ± ARG intervention (r = -0.396, p = 0.045). CONCLUSION: Combination of WPH and ARG enhances the satiating effect of nonivamide, providing opportunities to optimize satiating food formulations by low amounts of the individual food constituents.


Assuntos
Arginina/administração & dosagem , Capsaicina/análogos & derivados , Sobrepeso/psicologia , Hidrolisados de Proteína/administração & dosagem , Saciação/efeitos dos fármacos , Triticum/química , Adulto , Capsaicina/farmacologia , Estudos Cross-Over , Ingestão de Energia , Esvaziamento Gástrico/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Serotonina/sangue , Método Simples-Cego
4.
Geburtshilfe Frauenheilkd ; 77(3): 257-267, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28392579

RESUMO

Background Some studies have already proposed an inverse association between vitamin D levels and breast density. As breast density is already considered an established risk factor for breast cancer, such a connection could offer a new starting point for the prevention of breast cancer. Material and Methods To investigate this suggested connection, a total of 412 pre- and 572 post-menopausal women for whom mammography was indicated were recruited into this cross-sectional study. In addition to a questionnaire-based interview on the patient's general and gynecological medical history, her eating habits and lifestyle, serum levels of 25-hydroxyvitamin D [25(OH)D], calcium, phosphate and creatinine were determined. Breast density was determined by mammography and categorized as 1 to 4 according to the ACR classification. In addition to performing descriptive analysis to get a better overview of the data, a number of multivariate regression models were developed to determine the impact of confounders and the connection between vitamin D and mammographic density. Results More than half of all participants had low levels of 25(OH)D (< 20 ng/ml) and only a small minority of women (5.7 %) had what are currently considered to be optimal serum levels of 25(OH)D of at least 30 ng/ml. The significant majority of the cohort had a medium mammographic density (n = 463 had ACR 2; n = 343 had ACR 3). Logistic regression analysis showed that lower 25(OH)D serum levels were associated significantly more often with high rather than medium breast density. This association remained, even after adjusting for other factors which influence breast density such as age, BMI and menopausal status (p = 0.032 for ACR 4 vs. ACR 2; p = 0.028 for ACR 4 vs. ACR 3). When the same analysis was done separately for pre-menopausal and post-menopausal women, BMI in both groups was found to be inversely correlated with breast density and this inverse correlation was highly significant. In post-menopausal women, age was found to be similarly correlated while 25(OH)D did not appear to be associated with ACR. In pre-menopausal women the opposite was the case: although there was no correlation between age and breast density, higher vitamin D levels tended to be associated with lower breast density (p = 0.06 for ACR 2 vs. ACR 4) in this smaller sample (n = 412). When vitamin D-rich food and food supplements were also taken into account, regular intake of vitamin D preparations was associated with lower breast density; this association achieved borderline statistical significance (p = 0.05 for ACR 3 vs. ACR 4). When the analysis also took menopausal status into account, the breast density of pre-menopausal women was lower following regular vitamin D intake and this lower breast density of pre-menopausal women was statistically highly significant (p < 0.001 for ACR 1 and ACR 2 vs. ACR 4, respectively). This effect was not found in post-menopausal women. Frequent intake of vitamin D-containing nutrition had no significant impact on ACR in either of the groups. Conclusion These results reinforce the assumption previously proposed by several authors that higher levels of 25(OH)D pre-menopause and vitamin D substitution are associated with lower breast density and could reduce the risk of breast cancer. The findings did not confirm any post-menopausal association between vitamin D and mammographic breast density.

5.
Cancer Res ; 70(1): 357-66, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20028863

RESUMO

Adaptive responses to hypoxia in tumors are transcriptionally regulated by the hypoxia inducible factors (HIF-1alpha/HIF-2alpha), which are tightly controlled by the HIF-prolyl hydroxylases (PHD). Hypoxia induces expression of the PHD2 and PHD3 proteins in tumors but the pathobiological significance of these events is uncertain. Here, we show that PHD2 and PHD3 induction acts within a negative feedback loop to limit the hypoxic HIF response. In glioblastomas, PHD2 and PHD3 are hypoxia-inducible in vitro and expressed in hypoxic areas of tumors in vivo. Comparison with other PHDs revealed distinct cytoplasmatic and nuclear localization patterns of PHD2 and PHD3. Gain and loss of function experiments defined PHD2 and PHD3 as HIF target genes that remained operative even at low oxygen concentrations. We found that increased PHD levels could compensate for reduced oxygen availability to regulate the HIF response. This negative feedback loop protected tumor cells against hypoxia-induced cell death, functionally implicating this pathway in the control of the tumor-suppressive components of the HIF system in glioblastoma. Moreover, PHD inhibition facilitated cell death induction by staurosporine or tumor necrosis factor-related apoptosis-inducing ligand, hinting at a more general protective role of PHD in the regulation of cell viability. In summary, our findings recognize the PHD/HIF regulatory axis as a novel therapeutic target to disable a tumor's ability to adjust to hypoxic conditions and control cell survival, helping to potentially overcome therapeutic cell death resistance in glioblastomas.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Dioxigenases/metabolismo , Glioma/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Western Blotting , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Retroalimentação Fisiológica/fisiologia , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Prolina Dioxigenases do Fator Induzível por Hipóxia , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
6.
Cancer Cell ; 8(2): 131-41, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16098466

RESUMO

The hypoxia-inducible transcription factors HIF-1alpha and HIF-2alpha are activated in hypoxic tumor regions. However, their role in tumorigenesis remains controversial, as tumor growth promoter and suppressor activities have been ascribed to HIF-1alpha, while the role of HIF-2alpha remains largely unknown. Here, we show that overexpression of HIF-2alpha in rat glioma tumors enhances angiogenesis but reduces growth of these tumors, in part by increasing tumor cell apoptosis. Moreover, siRNA knockdown of HIF-2alpha reduced apoptosis in hypoxic human malignant glioblastoma cells. Furthermore, inhibition of HIF by overexpression of a dominant-negative HIF transgene in glioma cells or HIF-2alpha deficiency in teratomas reduced vascularization but accelerated growth of these tumor types. These findings urge careful consideration of using HIF inhibitors as cancer therapeutic strategies.


Assuntos
Glioma/irrigação sanguínea , Neovascularização Patológica , Fatores de Transcrição/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Animais , Apoptose , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Glioma/genética , Glioma/metabolismo , Humanos , Camundongos , Neoplasias Neuroepiteliomatosas/irrigação sanguínea , Neoplasias Neuroepiteliomatosas/genética , Neoplasias Neuroepiteliomatosas/metabolismo , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , RNA Interferente Pequeno/genética , Ratos , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Ativação Transcricional , Proteínas Supressoras de Tumor/antagonistas & inibidores , Proteínas Supressoras de Tumor/genética
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