GLORIA

GEOMAR Library Ocean Research Information Access

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    In: JAMA Internal Medicine, American Medical Association (AMA), Vol. 182, No. 9 ( 2022-09-01), p. 906-
    Type of Medium: Online Resource
    ISSN: 2168-6106
    Language: English
    Publisher: American Medical Association (AMA)
    Publication Date: 2022
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    In: Annals of Intensive Care, Springer Science and Business Media LLC, Vol. 13, No. 1 ( 2023-08-27)
    Abstract: The respective benefits of high and low doses of dexamethasone (DXM) in patients with severe acute respiratory syndrome coronavirus 2 (SARS-Cov2) and acute respiratory failure (ARF) are controversial, with two large triple-blind RCTs reaching very important difference in the effect-size. In the COVIDICUS trial, no evidence of additional benefit of high-dose dexamethasone (DXM20) was found. We aimed to explore whether some specific patient phenotypes could benefit from DXM20 compared to the standard of care 6 mg dose of DXM (DXMSoC). Methods We performed a post hoc exploratory Bayesian analysis of 473 patients who received either DXMSoc or DXM20 in the COVIDICUS trial. The outcome was the 60 day mortality rate of DXM20 over DXMSoC, with treatment effect measured on the hazard ratio (HR) estimated from Cox model. Bayesian analyses allowed to compute the posterior probability of a more than trivial benefit (HR  〈  0.95), and that of a potential harm (HR  〉  1.05). Bayesian measures of interaction then quantified the probability of interaction (Pr Interact) that the HR of death differed across the subsets by 20%. Primary analyses used noninformative priors, centred on HR = 1.00. Sensitivity analyses used sceptical and enthusiastic priors, based on null (HR = 1.00) or benefit (HR = 0.95) effects. Results Overall, the posterior probability of a more than trivial benefit and potential harm was 29.0 and 51.1%, respectively. There was some evidence of treatment by subset interaction (i) according to age (Pr Interact, 84%), with a 86.5% probability of benefit in patients aged below 70 compared to 22% in those aged above 70; (ii) according to the time since symptoms onset (Pr Interact, 99%), with a 99.9% probability of a more than trivial benefit when lower than 7 days compared to a  〈  0.1% probability when delayed by 7 days or more; and (iii) according to use of remdesivir (Pr Interact, 91%), with a 90.1% probability of benefit in patients receiving remdesivir compared to 19.1% in those who did not. Conclusions In this exploratory post hoc Bayesian analysis, compared with standard-of-care DXM, high-dose DXM may benefit patients aged less than 70 years with severe ARF that occurred less than 7 days after symptoms onset. The use of remdesivir may also favour the benefit of DXM20. Further analysis is needed to confirm these findings. Trial registration : NCT04344730, date of registration April 14, 2020 ( https://clinicaltrials.gov/ct2/show/NCT04344730?term=NCT04344730 & draw=2 & rank=1 ); EudraCT: 2020-001457-43 ( https://www.clinicaltrialsregister.eu/ctr-search/search?query=2020-001457-43 ).
    Type of Medium: Online Resource
    ISSN: 2110-5820
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2023
    detail.hit.zdb_id: 2617094-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    In: Critical Care, Springer Science and Business Media LLC, Vol. 26, No. 1 ( 2022-12)
    Abstract: Delaying time to prone positioning (PP) may be associated with higher mortality in acute respiratory distress syndrome (ARDS) due to coronavirus disease 2019 (COVID-19). We evaluated the use and the impact of early PP on clinical outcomes in intubated patients hospitalized in intensive care units (ICUs) for COVID-19. Methods All intubated patients with ARDS due to COVID-19 were involved in a secondary analysis from a prospective multicenter cohort study of COVID-ICU network including 149 ICUs across France, Belgium and Switzerland. Patients were followed-up until Day-90. The primary outcome was survival at Day-60. Analysis used a Cox proportional hazard model including a propensity score. Results Among 2137 intubated patients, 1504 (70.4%) were placed in PP during their ICU stay and 491 (23%) during the first 24 h following ICU admission. One hundred and eighty-one patients (36.9%) of the early PP group had a PaO 2 /FiO 2 ratio  〉  150 mmHg when prone positioning was initiated. Among non-early PP group patients, 1013 (47.4%) patients had finally been placed in PP within a median delay of 3 days after ICU admission. Day-60 mortality in non-early PP group was 34.2% versus 39.3% in the early PP group ( p  = 0.038). Day-28 and Day-90 mortality as well as the need for adjunctive therapies was more important in patients with early PP. After propensity score adjustment, no significant difference in survival at Day-60 was found between the two study groups (HR 1.34 [0.96–1.68], p  = 0.09 and HR 1.19 [0.998–1.412], p  = 0.053 in complete case analysis or in multiple imputation analysis, respectively). Conclusions In a large multicentric international cohort of intubated ICU patients with ARDS due to COVID-19, PP has been used frequently as a main treatment. In this study, our data failed to show a survival benefit associated with early PP started within 24 h after ICU admission compared to PP after day-1 for all COVID-19 patients requiring invasive mechanical ventilation regardless of their severity.
    Type of Medium: Online Resource
    ISSN: 1364-8535
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2022
    detail.hit.zdb_id: 2051256-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    In: Neuro-Oncology, Oxford University Press (OUP), Vol. 24, No. Supplement_1 ( 2022-06-03), p. i91-i91
    Abstract: Pediatric low-grade gliomas, a diverse group of WHO grade 1 and 2 glial or glioneural tumors, comprise the most common category of primary brain tumors in children. The majority of these tumors are driven by alterations in the MAPK pathway, making them in principle susceptible to MAPKi therapy. While patients often benefit from MAPKi during treatment, tumor rebound may occur once treatment is stopped, constituting a significant clinical challenge. BT-40, patient-derived cells with molecular features of pleomorphic xanthoastrocytoma (BRAFV600E, CDKN2Adel), were used to model the rebound growth in vitro, based on viable cell counts in response to treatment and withdrawal of the clinically relevant BRAFV600E specific inhibitor dabrafenib. Standard-of-care chemotherapy (vincristine and carboplatin) was used as a reference. MAPK pathway reactivation upon withdrawal was assessed by WB and qPCR analysis. Based on the observed cell-regrowth and MAPK-reactivation pattern, key-timepoints during withdrawal were identified, which are currently being further analyzed through RNAseq and phospho-/proteomics. BT-40 cells started to proliferate again two days after dabrafenib withdrawal, and earliest five days after chemotherapy withdrawal. MAPK pathway activity, based on Mek and Erk phosphorylation, reached baseline levels three hours after dabrafenib withdrawal, this was associated with 2.5-fold increased c-Fos gene expression two hours after withdrawal. The earlier cell regrowth after dabrafenib withdrawal compared to chemotherapy withdrawal matches clinical observations, making the model suitable to study the rebound. The observed MAPK overactivation suggests the growth rebound might not only be caused by a fast reactivation of the pathway but also by other mechanisms, e.g. accumulation of upstream activators due to loss of negative feedback or parallel pathways. To investigate this, key-timepoints during treatment withdrawal will be analyzed using a multi-omics approach. Based on these findings, possible rebound-driving mechanisms will be identified and further validated using BT-40 and additional PXA models in vitro and in vivo.
    Type of Medium: Online Resource
    ISSN: 1522-8517 , 1523-5866
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2022
    detail.hit.zdb_id: 2094060-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    In: Neuro-Oncology, Oxford University Press (OUP), Vol. 25, No. 4 ( 2023-04-06), p. 735-747
    Abstract: Pilocytic astrocytoma (PA) is the most common pediatric brain tumor and a mitogen-activated protein kinase (MAPK)-driven disease. Oncogenic MAPK-signaling drives the majority of cells into oncogene-induced senescence (OIS). While OIS induces resistance to antiproliferative therapies, it represents a potential vulnerability exploitable by senolytic agents. Methods We established new patient-derived PA cell lines that preserve molecular features of the primary tumors and can be studied in OIS and proliferation depending on expression or repression of the SV40 large T antigen. We determined expression of anti-apoptotic BCL-2 members in these models and primary PA. Dependence of senescent PA cells on anti-apoptotic BCL-2 members was investigated using a comprehensive set of BH3 mimetics. Results Senescent PA cells upregulate BCL-XL upon senescence induction and show dependency on BCL-XL for survival. BH3 mimetics with high affinity for BCL-XL (BCL-XLi) reduce metabolic activity and induce mitochondrial apoptosis in senescent PA cells at nano-molar concentrations. In contrast, BH3 mimetics without BCL-XLi activity, conventional chemotherapy, and MEK inhibitors show no effect. Conclusions Our data demonstrate that BCL-XL is critical for survival of senescent PA tumor cells and provides proof-of-principle for the use of clinically available BCL-XL-dependent senolytics.
    Type of Medium: Online Resource
    ISSN: 1522-8517 , 1523-5866
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2023
    detail.hit.zdb_id: 2094060-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    In: Neuro-Oncology, Oxford University Press (OUP), Vol. 23, No. Supplement_1 ( 2021-06-01), p. i33-i34
    Abstract: Pilocytic astrocytoma (PA) is the most common brain tumor in children. Activation of the mitogen-activated protein kinase (MAPK) pathway is a hallmark of PA. Complete remission in non-resectable tumors is infrequently observed with current therapeutic approaches. Most PA tumors cells are in oncogene-induced senescence (OIS), which may explain the benign growth behavior of PAs but also account for resistance to therapy. Therefore, treatment of PA with senolytic agents such as BH3-mimetics is a promising new approach. Methods Three patient-derived PA cell lines, DKFZ-BT66, DKFZ-BT308 (both KIAA1549:BRAF-fusion positive) and DKFZ-BT314 (BRAF V600E-mutation positive) were used. Depending on inducible expression or repression of SV40 large T antigen all models can reflect both states of PA, proliferation and OIS. Cells in both states were treated with different BH3-mimetics. Inhibition of metabolic activity was measured after 72 hours. Target expression was assessed by RT-qPCR and Western blot. On-target activity of BH3-mimetics was determined by immunoprecipitation (IP) of Bcl-xL/BAK. Results BH3-mimetics with strong binding affinity for Bcl-xL (Navitoclax, A-1131852, A-1155463) showed selectivity for senescent cells in 2/3 models (DKFZ-BT66 and DKFZ-BT314) and acted in nanomolar ranges. IC50s for Navitoclax (Cmax 6600nM in patients) were 40nM (OIS) vs. 200nM (proliferation) and 170nM (OIS) vs. 3700nM (proliferation) in DKFZ-BT66 and DKFZ-BT314, respectively. Target engagement was evident in the Bcl-xL/BAK-IP, and target expression of Bcl-xL was similar in all models studied. The relative resistance of senescent DKFZ-BT308 despite on-target activity is currently being investigated. Conclusion Senolytic treatment of PA with BH3-mimetics targeting Bcl-xL is a promising new strategy directly targeting the major senescent part of the tumor in clinically archivable concentrations. However, our data suggests that not all PAs may respond to treatment. The analysis of comparative gene expression analysis and BH3-profiling is ongoing to define predictive biomarkers.
    Type of Medium: Online Resource
    ISSN: 1522-8517 , 1523-5866
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2021
    detail.hit.zdb_id: 2094060-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    In: Neuro-Oncology, Oxford University Press (OUP), Vol. 24, No. Supplement_1 ( 2022-06-03), p. i91-i92
    Abstract: INTRODUCTION: Pilocytic astrocytoma (PA) is a mitogen-activated protein kinase (MAPK)-driven disease. Treatment of sub-totally resected PA remains challenging and relapses occur even after MAPK-targeted therapies such as MEK inhibition. Oncogenic activation of the MAPK-pathway drives the majority of cells into oncogene-induced senescence (OIS). OIS might represent a complementary vulnerability exploitable by senolytic agents. Here we investigated the senolytic properties of BH3-mimetics in PA. METHODS: Four patient-derived PA cell lines, DKFZ-BT66, -BT308, -BT317 (KIAA1549:BRAF-fusion) and DKFZ-BT314 (BRAF V600E-mutation) were treated with different BH3-mimetics, chemotherapeutics and MEK-inhibitors in proliferation (expression of SV40 large T (TAg)) and OIS (repression of TAg) states. Inhibition of metabolic activity (CellTiterGlo® 2.0) and reduction of viability (trypan blue) was assessed after 72 hours. Target expression was determined using gene expression data and Western blot. On-target activity was verified by immunoprecipitation. Dependence on Bcl-xL was investigated by shRNA-mediated knockdown and BH3-profiling. Gene expression data of primary PA and 751 cancer cell lines (GDSC dataset) was analyzed. RESULTS: BH3-mimetics inhibiting Bcl-xL (Bcl-xLi; Navitoclax, A-1131852, A-1155463, AZD4320) showed activity in 3/4 models (DKFZ-BT66, -BT314 and -BT317) in the OIS state (IC50s & lt;300nM). Other BH3-mimetics, chemotherapeutics and MEK-inhibitors had no effect on all models in OIS. Bcl-xL mRNA expression levels were similar, on-target activity and dependence on Bcl-xL protein was comparable in all models. Bcl-xLi-resistance of DKFZ-BT308 was linked to upregulation of genes of the HALLMARK_XENOBIOTICS_METABOLISM gene set involved in drug metabolism. Correlation of these genes with IC50s of navitoclax was validated in an independent dataset (GDSC). CONCLUSION: Treatment with Bcl-xLi is a promising strategy targeting the senescent part of PA. IC50s of the clinically available drug navitoclax were & gt;20-fold below achievable plasma concentration indicating translatability. Genes from the gene set HALLMARK_XENOBIOTICS_METABOLISM could represent a predictive biomarker.
    Type of Medium: Online Resource
    ISSN: 1522-8517 , 1523-5866
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2022
    detail.hit.zdb_id: 2094060-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    In: Clinical Pharmacology & Therapeutics, Wiley, Vol. 114, No. 4 ( 2023-10), p. 904-913
    Abstract: Novel drug treatments for pediatric patients with cancer are urgently needed. Success of drug development in pediatric oncology has been promising, but many drugs still fail in translation from preclinical to clinical phases. To increase the translational potential, several improvements have been implemented, including the use of clinically achievable concentrations in the drug testing phase. Although pharmacokinetic (PK) parameters of numerous investigated drugs are published, a comprehensive PK overview of the most common drugs in pediatric oncology could guide preclinical trial design and improve the translatability into clinical trials. A review of the literature was conducted for PK parameters of 74 anticancer drugs, from the drug sensitivity profiling library of the INdividualized Therapy FOr Relapsed Malignancies in Childhood (INFORM) registry. PK data in the pediatric population were reported and complemented by adult parameters when no pediatric data were available. In addition, blood–brain barrier (BBB)‐penetration assessment of drugs was provided by using the BBB score. Maximum plasma concentration was available for 73 (97%), area under the plasma concentration‐time curve for 69 (92%), plasma protein binding for 66 (88%), plasma half‐life for 57 (76%), time to maximum concentration for 54 (72%), clearance for 52 (69%), volume of distribution for 37 (49%), lowest plasma concentration reached by the drug before the next dose administration for 21 (28%), and steady‐state concentration for 4 (5%) of drugs. Pediatric PK data were available for 48 (65%) drugs. We provide a comprehensive review of PK data for 74 drugs studied in pediatric oncology. This data set can serve as a reference to design experiments more closely mimicking drug PK conditions in patients, and may thereby increase the probability of successful clinical translation.
    Type of Medium: Online Resource
    ISSN: 0009-9236 , 1532-6535
    URL: Issue
    RVK:
    Language: English
    Publisher: Wiley
    Publication Date: 2023
    detail.hit.zdb_id: 2040184-X
    SSG: 15,3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    In: Neuro-Oncology, Oxford University Press (OUP), Vol. 24, No. Supplement_1 ( 2022-06-03), p. i94-i94
    Abstract: Pilocytic astrocytomas (PA) are the most common pediatric brain tumors. They are characterized by driving alterations in the mitogen-activated protein kinase (MAPK) pathway, leading to its constitutive activation and modulating the balance between cell proliferation and oncogene-induced senescence (OIS) sustained by senescence-associated secretory phenotype (SASP) factors. This makes PA susceptible to MAPK inhibitor (MAPKi) therapies, which show encouraging results in phase 1/2 clinical trials. However, little is known about the molecular implications of MAPK inhibition in PA. The DKFZ-BT66 cell line, derived from a primary KIAA:BRAF-fusion positive PA, was used as a model system. DKFZ-BT66 were treated with the MEKi trametinib for different durations in both proliferative and senescent states. Gene expression was analyzed by gene expression profiling and protein expression/phospho-regulation by data-dependent mass spectrometry followed by label-free quantitative analysis. A time course analysis based on differentially expressed genes and phosphorylated proteins was performed, followed by a single-sample gene set enrichment analysis (ssGSEA) and kinase substrate enrichment analysis, respectively. Differential gene expression analysis revealed that MEK inhibition led to the inhibition of the OIS/SASP gene programs in senescent DKFZ-BT66, with downregulation of key OIS/SASP partners such as IL1B on the protein level. This functionally translated into a de-sensitization of these cells towards the senolytic agent navitoclax. ssGSEA showed that most MAPK-related signatures were downregulated upon MEKi treatment, while pathways related to upstream MAPK activators (including FGFR, NTRK and TGFB pathways) were upregulated, in both proliferating and senescent DKFZ-BT66. This data indicates that MAPKi reverses OIS in senescent PA cells, while inducing the activation of MAPK upstream regulators in proliferating and senescent PA cells, identifying putative co-targets that could help increase treatment’s efficacy. Validation of these targets by post-translational modification enrichment analysis of the phospho-proteomics dataset is ongoing.
    Type of Medium: Online Resource
    ISSN: 1522-8517 , 1523-5866
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2022
    detail.hit.zdb_id: 2094060-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    In: Neuro-Oncology, Oxford University Press (OUP), Vol. 23, No. Supplement_1 ( 2021-06-01), p. i5-i5
    Abstract: Medulloblastoma (MB) is one of the most common malignant pediatric CNS tumors. Patients with Group 3 MBs harboring MYC amplification exhibit low survival rates. Surviving patients suffer from therapy-induced sequelae, which calls for new targeted therapy strategies. We and others have previously shown the sensitivity of MYC-amplified MB to class I histone deacetylase (HDAC) inhibition. After demonstrating that the MYC target gene PLK1 is significantly downregulated upon class I HDACi treatment, we hypothesized that inhibition of both HDACs and PLK1 could have synergistic effects. Methods Cell metabolic activity changes upon HDAC and PLK1 inhibitor treatment were measured in MYC-amplified and non-amplified MB cell lines, as well as in an additional MYC-inducible cell line. The interaction effect of both inhibitors was determined by computation of the combination index (CI) using the Chou-Talalay method. Results were validated assessing cell viability, cell cycle, and apoptosis induction. Transcription profile changes after combination treatment were evaluated. Results MYC-amplified MB cell lines were more sensitive than non-amplified cell lines to PLK1i treatment, showing IC50 in clinically achievable concentration ranges. Inhibition of class I HDACs and PLK1 synergistically reduced cell metabolic activity in lower concentrations in MYC-amplified compared to non-amplified MB cell lines. We also observed a significant loss of viability and cells in G1 phase, as well as induction of apoptosis after combination treatment in MYC-amplified cells. MYC target gene sets were significantly downregulated in the MYC-amplified cell line HD-MB03 after treatment with combination. We demonstrated reduction of MYC protein levels upon PLK1i treatment. In vivo evaluation of combination treatment using orthotopic Group 3 MYC-amplified MB PDX models is ongoing. Conclusion Our data suggest that MYC-amplification is a predictive marker for PLK1i treatment in MB. The combination of HDACi and PLKi could be a candidate therapy for future clinical trials for MYC-amplified group 3 MB.
    Type of Medium: Online Resource
    ISSN: 1522-8517 , 1523-5866
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2021
    detail.hit.zdb_id: 2094060-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...