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
Filter
  • American Association for Cancer Research (AACR)  (6)
  • 2020-2024  (6)
  • Medicine  (6)
Material
Publisher
  • American Association for Cancer Research (AACR)  (6)
Language
Years
  • 2020-2024  (6)
Year
Subjects(RVK)
  • Medicine  (6)
RVK
  • 1
    In: Clinical Cancer Research, American Association for Cancer Research (AACR), Vol. 28, No. 4 ( 2022-02-15), p. 594-602
    Abstract: Therapeutic advances for glioblastoma have been minimal over the past 2 decades. In light of the multitude of recent phase III trials that have failed to meet their primary endpoints following promising preclinical and early-phase programs, a Society for Neuro-Oncology Think Tank was held in November 2020 to prioritize areas for improvement in the conduct of glioblastoma clinical trials. Here, we review the literature, identify challenges related to clinical trial eligibility criteria and trial design in glioblastoma, and provide recommendations from the Think Tank. In addition, we provide a data-driven context with which to frame this discussion by analyzing key study design features of adult glioblastoma clinical trials listed on ClinicalTrials.gov as “recruiting” or “not yet recruiting” as of February 2021.
    Type of Medium: Online Resource
    ISSN: 1078-0432 , 1557-3265
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2022
    detail.hit.zdb_id: 1225457-5
    detail.hit.zdb_id: 2036787-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    In: Clinical Cancer Research, American Association for Cancer Research (AACR), Vol. 26, No. 6 ( 2020-03-15), p. 1395-1407
    Abstract: Exploration of novel strategies to extend the benefit of PARP inhibitors beyond BRCA-mutant cancers is of great interest in personalized medicine. Here, we identified EGFR amplification as a potential biomarker to predict sensitivity to PARP inhibition, providing selection for the glioblastoma (GBM) patient population who will benefit from PARP inhibition therapy. Experimental Design: Selective sensitivity to the PARP inhibitor talazoparib was screened and validated in two sets [test set (n = 14) and validation set (n = 13)] of well-characterized patient-derived glioma sphere-forming cells (GSC). FISH was used to detect EGFR copy number. DNA damage response following talazoparib treatment was evaluated by γH2AX and 53BP1 staining and neutral comet assay. PARP–DNA trapping was analyzed by subcellular fractionation. The selective monotherapy of talazoparib was confirmed using in vivo glioma models. Results: EGFR-amplified GSCs showed remarkable sensitivity to talazoparib treatment. EGFR amplification was associated with increased reactive oxygen species (ROS) and subsequent increased basal expression of DNA-repair pathways to counterelevated oxidative stress, and thus rendered vulnerability to PARP inhibition. Following talazoparib treatment, EGFR-amplified GSCs showed enhanced DNA damage and increased PARP–DNA trapping, which augmented the cytotoxicity. EGFR amplification–associated selective sensitivity was further supported by the in vivo experimental results showing that talazoparib significantly suppressed tumor growth in EGFR-amplified subcutaneous models but not in nonamplified models. Conclusions: EGFR-amplified cells are highly sensitive to talazoparib. Our data provide insight into the potential of using EGFR amplification as a selection biomarker for the development of personalized therapy.
    Type of Medium: Online Resource
    ISSN: 1078-0432 , 1557-3265
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2020
    detail.hit.zdb_id: 1225457-5
    detail.hit.zdb_id: 2036787-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    In: Clinical Cancer Research, American Association for Cancer Research (AACR), Vol. 26, No. 5 ( 2020-03-01), p. 1094-1104
    Abstract: Glioblastoma is the most frequent and lethal primary brain tumor. Development of novel therapies relies on the availability of relevant preclinical models. We have established a panel of 96 glioblastoma patient-derived xenografts (PDX) and undertaken its genomic and phenotypic characterization. Experimental Design: PDXs were established from glioblastoma, IDH-wildtype (n = 93), glioblastoma, IDH-mutant (n = 2), diffuse midline glioma, H3 K27M-mutant (n = 1), and both primary (n = 60) and recurrent (n = 34) tumors. Tumor growth rates, histopathology, and treatment response were characterized. Integrated molecular profiling was performed by whole-exome sequencing (WES, n = 83), RNA-sequencing (n = 68), and genome-wide methylation profiling (n = 76). WES data from 24 patient tumors was compared with derivative models. Results: PDXs recapitulate many key phenotypic and molecular features of patient tumors. Orthotopic PDXs show characteristic tumor morphology and invasion patterns, but largely lack microvascular proliferation and necrosis. PDXs capture common and rare molecular drivers, including alterations of TERT, EGFR, PTEN, TP53, BRAF, and IDH1, most at frequencies comparable with human glioblastoma. However, PDGFRA amplification was absent. RNA-sequencing and genome-wide methylation profiling demonstrated broad representation of glioblastoma molecular subtypes. MGMT promoter methylation correlated with increased survival in response to temozolomide. WES of 24 matched patient tumors showed preservation of most genetic driver alterations, including EGFR amplification. However, in four patient–PDX pairs, driver alterations were gained or lost on engraftment, consistent with clonal selection. Conclusions: Our PDX panel captures the molecular heterogeneity of glioblastoma and recapitulates many salient genetic and phenotypic features. All models and genomic data are openly available to investigators.
    Type of Medium: Online Resource
    ISSN: 1078-0432 , 1557-3265
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2020
    detail.hit.zdb_id: 1225457-5
    detail.hit.zdb_id: 2036787-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2021
    In:  Cancer Research Vol. 81, No. 13_Supplement ( 2021-07-01), p. 2068-2068
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 81, No. 13_Supplement ( 2021-07-01), p. 2068-2068
    Abstract: Diffuse gliomas are highly aggressive brain tumors that invariably relapse despite treatment with chemo- and radiotherapy. Treatment with alkylating chemotherapy can drive tumors to develop a hypermutator phenotype. In contrast, the genomic effects of radiation therapy (RT) remain unknown. We analyzed the mutational spectra following treatment with ionizing radiation in sequencing data from 190 paired primary-recurrent gliomas from the Glioma Longitudinal Analysis (GLASS) dataset and 2116 post-treatment metastatic tumors from the Hartwig Medical Foundation. We identified a significant increase in the burden of small deletions following radiation therapy that was independent of other factors and was significantly associated with the clinically applied RT-dosage in Gy (P = 1e-02, multivariable log-linear regression). These novel deletions demonstrated distinct characteristics when compared to pre-existing deletions present prior to RT-treatment and deletions in RT-untreated tumors. Radiation therapy-acquired deletions were characterized by a larger deletion size (GLASS and metastatic cohort, P = 1.2e-02 and P = 8e-11, respectively; Mann-Whitney U test), an increased distance to repetitive DNA elements (P & lt; 2.2e-16, Kolmogorov-Smirnov test) and a reduction in microhomology at breakpoints (P = 3.2e-02, paired Wilcoxon signed-rank test). These observations suggested that canonical non-homologous end joining (c-NHEJ) was the preferred pathway for DNA double strand break repair of RT-induced DNA damage. Furthermore, radiotherapy resulted in frequent chromosomal deletions and significantly increased frequencies of CDKN2A homozygous deletions. Finally, a high burden of RT-associated deletions was associated with worse clinical outcomes (GLASS and metastatic cohort, P & lt; 1e-04 and P = 2.6e-02, respectively; Wald test). Our results collectively suggest that effective repair of RT-induced DNA damage is detrimental to patient survival and that inhibiting c-NHEJ may be a viable strategy for improving the cancer-killing effect of radiotherapy. Taken together, the identified genomic scars as a result of radiation therapy reflect a more aggressive tumor with increased levels of resistance to follow up treatments. Citation Format: Emre Kocakavuk, Kevin J. Anderson, Kevin C. Johnson, Frederick S. Varn, Samirkumar B. Amin, Erik P. Sulman, Floris P. Barthel, Roel G. Verhaak. Radiotherapy is associated with a deletion signature that contributes to poor cancer patient outcomes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2068.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2021
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    In: Clinical Cancer Research, American Association for Cancer Research (AACR), Vol. 26, No. 18 ( 2020-09-15), p. 4983-4994
    Abstract: Patients with central nervous system (CNS) tumors are typically treated with radiotherapy, but this is not curative and results in the upregulation of phosphorylated STAT3 (p-STAT3), which drives invasion, angiogenesis, and immune suppression. Therefore, we investigated the combined effect of an inhibitor of STAT3 and whole-brain radiotherapy (WBRT) in a murine model of glioma. Experimental Design: C57BL/6 mice underwent intracerebral implantation of GL261 glioma cells, WBRT, and treatment with WP1066, a blood–brain barrier–penetrant inhibitor of the STAT3 pathway, or the two in combination. The role of the immune system was evaluated using tumor rechallenge strategies, immune-incompetent backgrounds, immunofluorescence, immune phenotyping of tumor-infiltrating immune cells (via flow cytometry), and NanoString gene expression analysis of 770 immune-related genes from immune cells, including those directly isolated from the tumor microenvironment. Results: The combination of WP1066 and WBRT resulted in long-term survivors and enhanced median survival time relative to monotherapy in the GL261 glioma model (combination vs. control P & lt; 0.0001). Immunologic memory appeared to be induced, because mice were protected during subsequent tumor rechallenge. The therapeutic effect of the combination was completely lost in immune-incompetent animals. NanoString analysis and immunofluorescence revealed immunologic reprograming in the CNS tumor microenvironment specifically affecting dendritic cell antigen presentation and T-cell effector functions. Conclusions: This study indicates that the combination of STAT3 inhibition and WBRT enhances the therapeutic effect against gliomas in the CNS by inducing dendritic cell and T-cell interactions in the CNS tumor.
    Type of Medium: Online Resource
    ISSN: 1078-0432 , 1557-3265
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2020
    detail.hit.zdb_id: 1225457-5
    detail.hit.zdb_id: 2036787-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    In: Clinical Cancer Research, American Association for Cancer Research (AACR), Vol. 27, No. 8_Supplement ( 2021-04-15), p. PO-019-PO-019
    Abstract: Diffuse gliomas are highly aggressive brain tumors that invariably relapse despite treatment with chemo- and radiotherapy. Treatment with alkylating chemotherapy can drive tumors to develop a hypermutator phenotype. In contrast, the genomic effects of radiation therapy (RT) remain unknown. We analyzed the mutational spectra following treatment with ionizing radiation in sequencing data from 190 paired primary-recurrent gliomas from the Glioma Longitudinal Analysis (GLASS) dataset and 3693 post-treatment metastatic tumors from the Hartwig Medical Foundation (HMF). We identified a significant increase in the burden of small deletions following radiation therapy that was independent of other factors. These novel deletions demonstrated distinct characteristics when compared to pre-existing deletions present prior to RT-treatment and deletions in RT-untreated tumors. Radiation therapy-acquired deletions were characterized by a larger deletion size (GLASS and metastatic cohort, P=1.2e-02 and P=8e-11, respectively; Mann-Whitney U test), an increased distance to repetitive DNA elements (P & lt;2.2e-16, Kolmogorov-Smirnov test) and a reduction in microhomology at breakpoints (P=3.2e-02, paired Wilcoxon signed-rank test). These observations suggested that canonical non-homologous end joining (c-NHEJ) was the preferred pathway for DNA double strand break repair of RT-induced DNA damage. Furthermore, radiotherapy resulted in frequent chromosomal deletions and significantly increased frequencies of CDKN2A homozygous deletions. Finally, a high burden of RT-associated deletions was associated with worse clinical outcomes (GLASS and metastatic cohort, P & lt; 1e-04 and P = 2.6e-02, respectively; Wald test). Our results suggest that effective repair of RT-induced DNA damage is detrimental to patient survival and that inhibiting c-NHEJ may be a viable strategy for improving the cancer-killing effect of radiotherapy. Taken together, the identified genomic scars as a result of radiation therapy reflect a more aggressive tumor with increased levels of resistance to follow up treatments. Citation Format: Emre Kocakavuk, Kevin J. Anderson, Frederick S. Varn, Kevin C. Johnson, Samirkumar B. Amin, Erik. P. Sulman, Martijn Lolkema, Floris P. Barthel, Roel G.W. Verhaak. Radiotherapy in cancer is associated with a deletion signature that contributes to poor patient outcomes [abstract]. In: Proceedings of the AACR Virtual Special Conference on Radiation Science and Medicine; 2021 Mar 2-3. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(8_Suppl):Abstract nr PO-019.
    Type of Medium: Online Resource
    ISSN: 1078-0432 , 1557-3265
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2021
    detail.hit.zdb_id: 1225457-5
    detail.hit.zdb_id: 2036787-9
    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...