Kooperativer Bibliotheksverbund

In: Blood, American Society of Hematology, Vol. 132, No. Supplement 1 ( 2018-11-29), p. 588-588

Abstract: NOTCH1 is a cell surface receptor, regulation of which depends on the integrity and subsequent cleavage of its inhibitory domain. Subtle mechanical forces transmitted after ligand-binding [Wang et al., 2013] or removal of Ca2+-ions [Rand et al., 2000] make the site accessible for cleavage, resulting in release of the transcription factor NICD1. Mutations in NOTCH1 that prolong NICD1 activity have been found in chronic lymphocytic leukemia (CLL) with enrichment in up to 30% of Richter transformation (RT). Clinical trials have revealed that NOTCH1 mutant CLL derives no benefit from the addition of type I anti-CD20 monoclonal antibodies (mAb) such as rituximab. This lack of benefit has not been observed with the type II anti-CD20 mAb obinutuzumab. To understand how anti-CD20 mAbs influence NOTCH1, we studied intracellular signaling events induced by rituximab or obinutuzumab and assessed their implications on NOTCH1 signaling. As a model for this, mass spectrometry-based phosphoproteomic analysis was applied to rituximab or obinutuzumab treated SU-DHL4 B-lymphoma cells (1h and 24h time-points) and 〉 8500 phosphorylation sites measured relative to untreated controls. Activation of kinase pathways was inferred by kinase-substrate enrichment analysis (KSEA). NOTCH1 receptor activity was assessed by western blot for NICD1 and qPCR for HES1 expression (NICD1 target gene). We used rituximab F(ab')2 fragments, trastuzumab as an isotype control and SB2H2 to cross-link the IgG B-cell receptor (BCR). Where applicable, cells were pre-incubated with inhibitors for 48h before mAb exposure. Rituximab or obinutuzumab treatment resulted in strong phosphorylation of all proximal BCR signaling proteins at 1h and 24h, strongly activating MAPK and PLCγ2-induced signaling and remodeling processes in the actin cytoskeleton. Cell cycle promoting proteins were inhibited and in addition, obinutuzumab promoted pro-apoptotic signaling. AKT signaling was inhibited due to SHIP activation following FcγRIIB binding. We hypothesized that BCR-induced Ca2+-flux and/or mechanical forces inflicted by cytoskeletal rearrangements disrupt the integrity of the inhibitory domain of NOTCH1 and promote ligand-independent activation. A strong, immediate increase in NOTCH1 activity was observed after rituximab, rituximab F(ab')2 and SB2H2 treatment. This was preventable by SYK inhibition, which also abrogated Ca2+-flux. Neither Ca2+-flux nor a relevant increase in NICD1 activity were induced by obinutuzumab, clearly supporting our first hypothesis. To test, if cytoskeletal rearrangements also contributed to NOTCH1 activation, we treated cells with a Rac inhibitor and found significantly reduced basal HES1 expression. PI-4,5-P2, which is the substrate for the Pi3-kinase (Pi3K), suppresses Ca2+-flux and cytoskeletal rearrangements. In vitro, the Pi3K inhibitors idelalisib, duvelisib and umbralisib reduced maximum HES1 expression after rituximab exposure as well as basal HES1 expression levels significantly more than BTK inhibition. Thus, Pi3K inhibitors likely act as suppressors of NOTCH1 signaling. Abnormally strong NOTCH1 signaling is one driver of RT and our observations can serve as explanation why idelalisib treated patients might develop RT at lower rates than patients treated with ibrutinib or venetoclax. In summary, we demonstrate clear and direct links between BCR and NOTCH1 signaling and show that anti-CD20 mAbs induce cell cycle arrest and apoptosis after strong BCR signaling. With c-MYC as an established target gene, NICD1 release upon Ca2+-flux and cytoskeletal movements in B-cells generates survival and proliferation signals. BCR-triggered effects on cell fate depend on signal strength and vary between activation/survival and apoptosis, the latter occurring when signal strength exceeds a threshold. CLL cells have low CD20 expression and the threshold for apoptosis induction after anti-CD20 mAb treatment may thus be difficult to reach. NOTCH1 mutations leading to abnormally strong effects of NICD1 would then lead to a prominence of survival over apoptotic signals, thereby promoting the observed resistance to rituximab. We believe that Ca2+-flux inducing type I anti-CD20 mAbs should be avoided in the treatment of NOTCH1 mutant CLL. Furthermore, we hypothesize that patients at increased risk for RT (mutant NOTCH1, c-MYC gain, highly autoreactive BCR) may benefit from Pi3K inhibition. Disclosures Cragg: Boehringer Ingleheim: Consultancy; Bioinvent: Consultancy, Patents & Royalties: Patent licenced to Bioinvent around CD32b blockade. Gribben:TG Therapeutics: Honoraria; NIH: Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Novartis: Honoraria; Acerta Pharma: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Wellcome Trust: Research Funding; Kite: Honoraria; Roche: Honoraria; Unum: Equity Ownership; Cancer Research UK: Research Funding; Medical Research Council: Research Funding; Abbvie: Honoraria; Pharmacyclics: Honoraria.

Type of Medium: Online Resource

ISSN: 0006-4971 , 1528-0020

URL: Article

DOI: 10.1182/blood-2018-99-116490

Language: English

Publisher: American Society of Hematology

Publication Date: 2018

detail.hit.zdb_id: 1468538-3

detail.hit.zdb_id: 80069-7

In: Diabetes Care, American Diabetes Association, Vol. 44, No. 5 ( 2021-05-01), p. 1219-1227

Abstract: In observational data, lower levels of lipoprotein(a) have been associated with greater prevalence of type 2 diabetes. Whether pharmacologic lowering of lipoprotein(a) influences incident type 2 diabetes is unknown. We determined the relationship of lipoprotein(a) concentration with incident type 2 diabetes and effects of treatment with alirocumab, a PCSK9 inhibitor. RESEARCH DESIGN AND METHODS In the ODYSSEY OUTCOMES trial alirocumab was compared with placebo in patients with acute coronary syndrome. Incident diabetes was determined from laboratory, medication, and adverse event data. RESULTS Among 13,480 patients without diabetes at baseline, 1,324 developed type 2 diabetes over a median 2.7 years. Median baseline lipoprotein(a) was 21.9 mg/dL. With placebo, 10 mg/dL lower baseline lipoprotein(a) was associated with hazard ratio 1.04 (95% CI 1.02−1.06, P & lt; 0.001) for incident type 2 diabetes. Alirocumab reduced lipoprotein(a) by a median 23.2% with greater absolute reductions from higher baseline levels and no overall effect on incident type 2 diabetes (hazard ratio 0.95, 95% CI 0.85–1.05). At low baseline lipoprotein(a) levels, alirocumab tended to reduce incident type 2 diabetes, while at high baseline lipoprotein(a) alirocumab tended to increase incident type 2 diabetes compared with placebo (treatment–baseline lipoprotein(a) interaction P = 0.006). In the alirocumab group, a 10 mg/dL decrease in lipoprotein(a) from baseline was associated with hazard ratio 1.07 (95% CI 1.03−1.12; P = 0.0002) for incident type 2 diabetes. CONCLUSIONS In patients with acute coronary syndrome, baseline lipoprotein(a) concentration associated inversely with incident type 2 diabetes. Alirocumab had neutral overall effect on incident type 2 diabetes. However, treatment-related reductions in lipoprotein(a), more pronounced from high baseline levels, were associated with increased risk of incident type 2 diabetes. Whether these findings pertain to other therapies that reduce lipoprotein(a) is undetermined.

Type of Medium: Online Resource

ISSN: 0149-5992 , 1935-5548

URL: Article

DOI: 10.2337/dc20-2842

Language: English

Publisher: American Diabetes Association

Publication Date: 2021

detail.hit.zdb_id: 1490520-6

In: Nanoscale, Royal Society of Chemistry (RSC), Vol. 15, No. 2 ( 2023), p. 742-756

Abstract: Super-resolution fluorescence microscopy has revolutionized multicolor imaging of nuclear structures due to the combination of high labeling specificity and high resolution. Here we expanded the recently developed fBALM (DNA structure fluctuation-assisted binding activated localization microscopy) method by developing a stable methodological sequence that enables dual-color imaging of high-resolution genomic DNA together with an immunofluorescently labeled intranuclear protein. Our measurements of the nuclear periphery, imaging DNA and LaminB1 in biologically relevant samples, show that this novel dual-color imaging method is feasible for further quantitative evaluations. We were able to study the relative spatial signal organization between DNA and LaminB1 by means of highly specific colocalization measurements at nanometer resolution. Measurements were performed with and without the antifade embedding medium ProLong Gold, which proved to be essential for imaging of LaminB1, but not for imaging of SytoxOrange labeled DNA. The localization precision was used to differentiate between localizations with higher and lower amounts of emitting photons. We interpret high intensity localizations to be renatured DNA sections in which a high amount of Sytox Orange molecules were bound. This could give insight into the denaturation kinetics of DNA during fBALM. These results were further complemented by measurements of γH2AX and H3K9me3 signal organization to demonstrate differences within the chromatin landscape, which were quantified with image processing methods such as Voronoi segmentation.

Type of Medium: Online Resource

ISSN: 2040-3364 , 2040-3372

URL: Article

DOI: 10.1039/D2NR02684H

Language: English

Publisher: Royal Society of Chemistry (RSC)

Publication Date: 2023

detail.hit.zdb_id: 2515664-0

In: Nature Communications, Springer Science and Business Media LLC, Vol. 12, No. 1 ( 2021-09-13)

Abstract: Knowledge of the genomic landscape of chronic lymphocytic leukemia (CLL) grows increasingly detailed, providing challenges in contextualizing the accumulated information. To define the underlying networks, we here perform a multi-platform molecular characterization. We identify major subgroups characterized by genomic instability (GI) or activation of epithelial-mesenchymal-transition (EMT)-like programs, which subdivide into non-inflammatory and inflammatory subtypes. GI CLL exhibit disruption of genome integrity, DNA-damage response and are associated with mutagenesis mediated through activation-induced cytidine deaminase or defective mismatch repair. TP53 wild-type and mutated/deleted cases constitute a transcriptionally uniform entity in GI CLL and show similarly poor progression-free survival at relapse. EMT-like CLL exhibit high genomic stability, reduced benefit from the addition of rituximab and EMT-like differentiation is inhibited by induction of DNA damage. This work extends the perspective on CLL biology and risk categories in TP53 wild-type CLL. Furthermore, molecular targets identified within each subgroup provide opportunities for new treatment approaches.

Type of Medium: Online Resource

ISSN: 2041-1723

URL: Article

DOI: 10.1038/s41467-021-25403-y

Language: English

Publisher: Springer Science and Business Media LLC

Publication Date: 2021

detail.hit.zdb_id: 2553671-0

In: iScience, Elsevier BV, Vol. 24, No. 2 ( 2021-02), p. 102089-

Type of Medium: Online Resource

ISSN: 2589-0042

URL: Article

DOI: 10.1016/j.isci.2021.102089

Language: English

Publisher: Elsevier BV

Publication Date: 2021

detail.hit.zdb_id: 2927064-9

In: Journal of the American College of Cardiology, Elsevier BV, Vol. 78, No. 5 ( 2021-08), p. 421-433

Type of Medium: Online Resource

ISSN: 0735-1097

URL: Article

DOI: 10.1016/j.jacc.2021.04.102

Language: English

Publisher: Elsevier BV

Publication Date: 2021

detail.hit.zdb_id: 1468327-1

In: Blood, American Society of Hematology, Vol. 136, No. Supplement 1 ( 2020-11-5), p. 12-13

Abstract: Background: Genomically instable (GI) chronic lymphocytic leukemia (CLL) is characterized by frequent alterations in DNA-damage response (DDR) genes (e.g. TP53,ATM) and related pathways. Conversely, pathogenic networks in CLL cases which maintain genomic integrity and operate with a functional DDR remain incompletely described. Methods: Molecular profiling was conducted on CD19 sorted samples derived from patients registered on the CLL8 study (1st-line, FC vs. FCR) for gene expression (GEP)(n=337, Exon 1.0 ST arrays, Affymetrix), copy number aberrations (CNAs) (n=309, SNP Arrays 6.0, Affymetrix) and mutation analyses/signature projections (n=171, whole exome sequencing, Illumina). FISH, IGHV and TP53 mutation analysis was conducted at trial enrolment. Results: Unsupervised consensus clustering (k=2-6) on variably expressed genes (SD & gt;0.5) was used for class discovery. Two small, but highly differentiated clusters were identified, characterized through NRIP1 and EBF1/tri12. GSEA also segregated the remaining samples into four major clusters showing signatures of inflammation (I) and without inflammation (NI). These clusters were further segregated into GI-CLL clusters with increased "DNA-repair" or clusters with "epithelial-mesenchymal transition"-like signatures (EMT-L). Variability for del(17p)/TP53 mutation was found across clusters (p & lt;0.01), with a low incidence observed in (I/NI)EMT-L (28.3%) vs. (I/NI)GI (71.7%). GISTIC identified CNA enrichment (FDR≤0.25) and potential target genes in affected regions impacting genomic stability and inflammation. (I/NI)GI had gains covering MYC (8q24.21), XPO1/REL (2p16.1) and (NI)GI showed losses involving KNSTRN and BUB1B (15q15.1). Mutational signatures implicated in pathogenic processes in cancer (COSMIC database) showed low activations for signatures indicating defective MMR or DSB repair in (I)EMT-L compared to (NI)GI, especially in IGHV mutated cases. Low p53 and phospho-p53 protein levels indicated a dampened DDR in (I/NI)EMT-L. Losses of 11q22.1-q22.2 and losses exceeding cytoband 13q21.1 were identified in (I/NI)GI. Since affected genes (e.g. YAP1, MMP, protocadherins) are closely linked with EMT in solid tumors, these regions seem indispensable for genomically stable CLL with EMT-like networks. Due to the high frequency of alterations associated with genomic instability and inverse TP53 and ZEB1 GEP, we hypothesized that p53 activation inhibits EMT-like networks in CLL. Cell lines showed miR-200c induction and decrease of target EMT transcription factors ZEB1/TWIST1 after irradiation, resembling the p53-miR-200c-ZEB1 mediated EMT-suppression in solid tumors. To further study these observations we performed mass spectrometry proteomics analysis on two syngeneic murine models; Eμ-myc [C57BL/6J-TgN(Ighmyc)22Bri/J] hemizygous and Eμ-TCL1 [C57BL/6J-TgN(IghTCL1)22Bri/J] hemizygous and compared their CD19-MACS isolated malignant B cells to normal splenic B cells from wildtype mice. Proteome profiles from Eµ-MYC/Eµ-TCL1 mouse samples mirrored GSEA findings in patient samples showing DDR-induction and concurrent downregulation of EMT associated signatures, including inflammation and hypoxia. EMT-like CLL showed transcriptional signatures indicating inflammation in the majority of cases, increased motility, NOTCH-/TGFb-signaling and HIF1a upregulation; all central characteristics observed for EMT. Excluding cases with TP53 defect, (NI)GI showed PFS rates of 17% at 5 years vs. 47% in (I)EMT-L ((NI)GI: median PFS 29.8 vs. (I)EMT-L: 39.5 months, HR:1.83 (95%CI 1.12-3.01), p=0.02) when treated with FC. Addition of rituximab improved outcome only in (NI)GI showing PFS rates of 44% at 5 years, in contrast to 45% at 5 years in (I)EMT-L ((NI)GI: median PFS 58.3 vs. (I)EMT-L: 52.4 months, HR:1.07 (95%CI 0.65-1.74), p=0.797). (I)EMT-L cases therefore lack an increase of efficacy for the addition of rituximab. Conclusion: We identify distinct biologic subtypes in CLL, characterized by either genomic instability or EMT-like networks which show heterogeneous extent of inflammation and a differential response to treatment. Maintenance of genomic stability and dampened DDR seem critical for pathogenic networks emerging in EMT-like CLL due to the reciprocal inhibition of underlying processes and provide a potential entry point for rational therapeutic intervention. Disclosures Eichhorst: ArQule: Consultancy, Honoraria, Other: travel support, Research Funding; BeiGene: Consultancy, Honoraria, Other: travel support, Research Funding; Gilead: Consultancy, Honoraria, Other: travel support, Research Funding; AstraZeneca: Consultancy, Honoraria, Other: travel support, Research Funding; Oxford Biomedica: Consultancy, Honoraria, Other: travel support, Research Funding; F. Hoffmann-LaRoche: Consultancy, Honoraria, Other: travel support, Research Funding; AbbVie: Consultancy, Honoraria, Other: travel support, Research Funding; Janssen-Cilag: Consultancy, Honoraria, Other: travel support, Research Funding; Celgene: Consultancy, Honoraria, Other: travel support, Research Funding; Novartis: Consultancy, Honoraria, Other: travel support, Research Funding. Yeh:Genentech: Current Employment. Weisser:Roche: Current Employment, Current equity holder in publicly-traded company. Fischer:AbbVie: Honoraria; F. Hoffmann-La Roche: Honoraria, Other: travel grants. Gribben:Abbvie: Honoraria; Celgene: Research Funding; Janssen: Honoraria, Research Funding; AstraZeneca: Honoraria, Research Funding. Landau:Bristol Myers Squibb: Research Funding; Illumina: Research Funding. Neuberg:Celgene: Research Funding; Madrigak Pharmaceuticals: Current equity holder in publicly-traded company; Pharmacyclics: Research Funding. Hallek:Gilead: Consultancy, Honoraria, Research Funding; F. Hoffmann-LaRoche: Consultancy, Honoraria, Research Funding; AbbVie: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Mundipharma: Consultancy, Honoraria, Research Funding. Wu:Pharmacyclics: Research Funding; BionTech: Current equity holder in publicly-traded company. Döhner:Abbvie: Consultancy, Honoraria; Agios: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; AROG: Research Funding; Astellas: Consultancy, Honoraria, Research Funding; Astex: Consultancy, Honoraria; Bristol Myers Squibb: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria; Jazz: Consultancy, Honoraria, Research Funding; Helsinn: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Research Funding; Oxford Biomedicals: Consultancy, Honoraria; Pfizer: Research Funding; Roche: Consultancy, Honoraria; Sunesis: Research Funding; AstraZeneca: Consultancy, Honoraria; GEMoaB: Consultancy, Honoraria. Stilgenbauer:Amgen: Consultancy, Honoraria, Other: travel support, Research Funding; Celgene: Consultancy, Honoraria, Other: travel support, Research Funding; Janssen-Cilag: Consultancy, Honoraria, Other: travel support, Research Funding; GlaxoSmithKline: Consultancy, Honoraria, Other: travel support, Research Funding; Genzyme: Consultancy, Honoraria, Other: travel support, Research Funding; AbbVie: Consultancy, Honoraria, Other: travel support, Research Funding; Boehringer-Ingelheim: Consultancy, Honoraria, Other: travel support, Research Funding; Gilead: Consultancy, Honoraria, Other: travel support, Research Funding; Genentech: Consultancy, Honoraria, Other: travel support, Research Funding; Pharmacyclics: Consultancy, Honoraria, Other, Research Funding; Mundipharma: Consultancy, Honoraria, Other, Research Funding; F. Hoffmann-LaRoche: Consultancy, Honoraria, Other: travel support, Research Funding; Novartis: Consultancy, Honoraria, Other, Research Funding.

Type of Medium: Online Resource

ISSN: 0006-4971 , 1528-0020

URL: Article

DOI: 10.1182/blood-2020-141552

Language: English

Publisher: American Society of Hematology

Publication Date: 2020

detail.hit.zdb_id: 1468538-3

detail.hit.zdb_id: 80069-7

In: Circulation, Ovid Technologies (Wolters Kluwer Health), Vol. 146, No. 9 ( 2022-08-30), p. 657-672

Abstract: Apolipoprotein B (apoB) provides an integrated measure of atherogenic risk. Whether apoB levels and apoB lowering hold incremental predictive information on residual risk after acute coronary syndrome beyond that provided by low-density lipoprotein cholesterol is uncertain. Methods: The ODYSSEY OUTCOMES trial (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) compared the proprotein convertase subtilisin/kexin type 9 inhibitor alirocumab with placebo in 18 924 patients with recent acute coronary syndrome and elevated atherogenic lipoproteins despite optimized statin therapy. Primary outcome was major adverse cardiovascular events (MACE; coronary heart disease death, nonfatal myocardial infarction, fatal/nonfatal ischemic stroke, hospitalization for unstable angina). Associations between baseline apoB or apoB at 4 months and MACE were assessed in adjusted Cox proportional hazards and propensity score–matched models. Results: Median follow-up was 2.8 years. In proportional hazards analysis in the placebo group, MACE incidence increased across increasing baseline apoB strata (3.2 [95% CI, 2.9–3.6], 4.0 [95% CI, 3.6–4.5] , and 5.5 [95% CI, 5.0–6.1] events per 100 patient-years in strata 〈 75, 75– 〈 90, ≥90 mg/dL, respectively; P trend 〈 0.0001) and after adjustment for low-density lipoprotein cholesterol ( P trend =0.035). Higher baseline apoB stratum was associated with greater relative ( P trend 〈 0.0001) and absolute reduction in MACE with alirocumab versus placebo. In the alirocumab group, the incidence of MACE after month 4 decreased monotonically across decreasing achieved apoB strata (4.26 [95% CI, 3.78–4.79], 3.09 [95% CI, 2.69–3.54] , and 2.41 [95% CI, 2.11–2.76] events per 100 patient-years in strata ≥50, 〉 35– 〈 50, and ≤35 mg/dL, respectively). Compared with propensity score–matched patients from the placebo group, treatment hazard ratios for alirocumab also decreased monotonically across achieved apoB strata. Achieved apoB was predictive of MACE after adjustment for achieved low-density lipoprotein cholesterol or non–high-density lipoprotein cholesterol but not vice versa. Conclusions: In patients with recent acute coronary syndrome and elevated atherogenic lipoproteins, MACE increased across baseline apoB strata. Alirocumab reduced MACE across all strata of baseline apoB, with larger absolute reductions in patients with higher baseline levels. Lower achieved apoB was associated with lower risk of MACE, even after accounting for achieved low-density lipoprotein cholesterol or non–high-density lipoprotein cholesterol, indicating that apoB provides incremental information. Achievement of apoB levels as low as ≤35 mg/dL may reduce lipoprotein-attributable residual risk after acute coronary syndrome. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01663402.

Type of Medium: Online Resource

ISSN: 0009-7322 , 1524-4539

URL: Article

DOI: 10.1161/CIRCULATIONAHA.121.057807

Language: English

Publisher: Ovid Technologies (Wolters Kluwer Health)

Publication Date: 2022

detail.hit.zdb_id: 1466401-X

In: The Lancet Diabetes & Endocrinology, Elsevier BV, Vol. 7, No. 8 ( 2019-08), p. 618-628

Type of Medium: Online Resource

ISSN: 2213-8587

URL: Article

DOI: 10.1016/S2213-8587(19)30158-5

Language: English

Publisher: Elsevier BV

Publication Date: 2019

In: Progress in Organic Coatings, Elsevier BV, Vol. 20, No. 2 ( 1992-5), p. 105-138

Type of Medium: Online Resource

ISSN: 0300-9440

URL: Article

DOI: 10.1016/0033-0655(92)80001-D

Language: English

Publisher: Elsevier BV

Publication Date: 1992

detail.hit.zdb_id: 2015714-9