76 results on '"Steele AJ"'
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2. Low-moment magnetism in the double perovskites Ba2MOsO6 (M=Li,Na)
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Steele, AJ, Baker, PJ, Lancaster, T, Pratt, FL, Franke, I, Ghannadzadeh, S, Goddard, PA, Hayes, W, Prabhakaran, D, and Blundell, SJ
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Condensed Matter - Strongly Correlated Electrons ,Strongly Correlated Electrons (cond-mat.str-el) ,FOS: Physical sciences ,Condensed Matter::Strongly Correlated Electrons - Abstract
The magnetic ground states of the isostructural double perovskites Ba$_2$NaOsO$_6$ and Ba$_2$LiOsO$_6$ are investigated with muon-spin rotation. In Ba$_2$NaOsO$_6$ long-range magnetic order is detected via the onset of a spontaneous muon-spin precession signal below $T_{\mathrm{c}}=7.2\pm 0.2\;\mathrm{K}$, while in Ba$_2$LiOsO$_6$ a static but spatially-disordered internal field is found below 8 K. A novel probabilistic argument is used to show from the observed precession frequencies that the magnetic ground state in Ba$_2$NaOsO$_6$ is most likely to be low-moment ($\approx 0.2$\,$\mu_{\rm B}$) ferromagnetism and not canted antiferromagnetism. Ba$_2$LiOsO$_6$ is antiferromagnetic and we find a spin-flop transition at 5.5\,T. A reduced osmium moment is common to both compounds, probably arising from a combination of spin-orbit coupling and frustration., Comment: 4 pages, 4 figures
- Published
- 2011
3. Detection of serum reverse transcriptase activity in patients with ALS and unaffected blood relatives.
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Steele AJ, Al-Chalabi A, Ferrante K, Cudkowicz ME, Brown RH Jr., and Garson JA
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- 2005
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4. Network analysis reveals a major role for 14q32 cluster miRNAs in determining transcriptional differences between IGHV-mutated and unmutated CLL.
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Bryant D, Smith L, Rogers-Broadway KR, Karydis L, Woo J, Blunt MD, Forconi F, Stevenson FK, Goodnow C, Russell A, Humburg P, Packham G, Steele AJ, and Strefford JC
- Subjects
- Humans, Immunoglobulin Heavy Chains genetics, Mutation, RNA, Messenger genetics, Leukemia, Lymphocytic, Chronic, B-Cell genetics, Leukemia, Lymphocytic, Chronic, B-Cell pathology, MicroRNAs genetics
- Abstract
Chronic lymphocytic leukaemia (CLL) cells can express unmutated (U-CLL) or mutated (M-CLL) immunoglobulin heavy chain (IGHV) genes with differing clinical behaviours, variable B cell receptor (BCR) signalling capacity and distinct transcriptional profiles. As it remains unclear how these differences reflect the tumour cells' innate pre/post germinal centre origin or their BCR signalling competence, we applied mRNA/miRNA sequencing to 38 CLL cases categorised into three subsets by IGHV mutational status and BCR signalling capacity. We identified 492 mRNAs and 38 miRNAs differentially expressed between U-CLL and M-CLL, but only 9 mRNAs and 0 miRNAs associated with BCR competence within M-CLL. Of the IGHV-associated miRNAs, (14/38 (37%)) derived from chr14q32 clusters where all miRNAs were co-expressed with the MEG3 lncRNA from a cancer associated imprinted locus. Integrative analysis of miRNA/mRNA data revealed pronounced regulatory potential for the 14q32 miRNAs, potentially accounting for up to 25% of the IGHV-related transcriptome signature. GAB1, a positive regulator of BCR signalling, was potentially regulated by five 14q32 miRNAs and we confirmed that two of these (miR-409-3p and miR-411-3p) significantly repressed activity of the GAB1 3'UTR. Our analysis demonstrates a potential key role of the 14q32 miRNA locus in the regulation of CLL-related gene regulation., (© 2023. The Author(s).)
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- 2023
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5. Clinical impact of ibrutinib plus R-CHOP in untreated DLBCL coexpressing BCL2 and MYC in the phase 3 PHOENIX trial.
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Johnson PWM, Balasubramanian S, Hodkinson B, Shreeve SM, Sun S, Srinivasan S, Steele AJ, Vermeulen J, Sehn LH, and Wilson WH
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- Humans, Antibodies, Monoclonal, Murine-Derived, Cyclophosphamide therapeutic use, Doxorubicin therapeutic use, Prednisone therapeutic use, Proto-Oncogene Proteins c-bcl-2 genetics, Proto-Oncogene Proteins c-bcl-2 metabolism, Rituximab therapeutic use, Vincristine therapeutic use, Lymphoma, Large B-Cell, Diffuse diagnosis, Lymphoma, Large B-Cell, Diffuse drug therapy, Lymphoma, Large B-Cell, Diffuse genetics, Proto-Oncogene Proteins c-myc metabolism
- Abstract
Diffuse large B-cell lymphoma (DLBCL), with high coexpression of BCL2 and MYC proteins (DE lymphoma), is considered an adverse prognostic indicator associated mostly with non-germinal center B-cell-like (non-GCB) DLBCL. BCL2/MYC overexpression is associated with B-cell receptor (BCR) pathway activation; consequently, DE DLBCL may be sensitive to BCR inhibitors. We assessed whether high BCL2/MYC coexpression by RNA sequencing could identify a patient subset responsive to ibrutinib using baseline biopsies from the PHOENIX trial, which evaluated the addition of ibrutinib to rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in untreated non-GCB DLBCL. BCL2/MYC RNA expression was correlated with lower event-free survival (EFS) and overall survival (OS) using Kaplan-Meier estimates with Cox regression and log-rank testing. In total, 234 of 766 (30.5%) patients had high BCL2/MYC coexpression: 123 of 386 (31.9%) received ibrutinib plus R-CHOP and 111 of 380 (29.2%) received R-CHOP. EFS was superior with ibrutinib plus R-CHOP compared with R-CHOP alone in patients with high BCL2/MYC coexpression, but there was no significant impact on OS. However, EFS and OS showed clinically meaningful improvement with ibrutinib plus R-CHOP over R-CHOP alone in patients aged <60 years with high BCL2/MYC coexpression. We observed a significant association between high BCL2/MYC coexpression and activated B-cell-like and MYD88L265P/CD79B-mutated subtypes of DLBCL. Consequently, high BCL2/MYC coexpression identified a subset of non-GCB DLBCL that may be preferentially responsive to ibrutinib and warrants further investigation. This trial was registered at www.clinicaltrials.gov as #NCT01855750., (Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution.)
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- 2023
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6. Pharmacist-Driven Geriatric Medication Assessment at an Acute Care Teaching Hospital.
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Steele AJ, Berletic JD, and Gionfriddo MR
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- Humans, Aged, Potentially Inappropriate Medication List, Hospitalization, Hospitals, Teaching, Pharmacists, Drug-Related Side Effects and Adverse Reactions prevention & control
- Abstract
Older patients are often prescribed many medications and are at higher risk for medication-related problems. Pharmacists can help to identify potentially inappropriate medication use that may precipitate adverse drug events resulting in mental status changes, falls, and hospitalization. A Pharmacist-Driven Geriatric Medication Assessment program was established by clinical pharmacists to evaluate medication use in older patients admitted to a pilot unit of an acute care hospital as part of an Age-Friendly Care initiative. This article describes the implementation of this program and the types of medication interventions pursued by the pharmacists. Pharmacist recommendation acceptance rate by the health care team was greater than 90% overall for medication reconciliation, potentially inappropriate medications, and other medication interventions.
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- 2023
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7. BTK-independent regulation of calcium signalling downstream of the B-cell receptor in malignant B-cells.
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Arthur R, Wathen A, Lemm EA, Stevenson FK, Forconi F, Linley AJ, Steele AJ, Packham G, and Valle-Argos B
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- Agammaglobulinaemia Tyrosine Kinase, Calcium pharmacology, Drug Resistance, Neoplasm, Humans, Phospholipase C gamma, Protein Kinase Inhibitors pharmacology, Pyrazoles pharmacology, Pyrimidines pharmacology, Receptors, Antigen, B-Cell metabolism, Leukemia, Lymphocytic, Chronic, B-Cell drug therapy, Leukemia, Lymphocytic, Chronic, B-Cell pathology
- Abstract
BTK inhibitors (BTKi) have dramatically improved outcomes for patients with chronic lymphocytic leukaemia (CLL) and some forms of B-cell lymphoma. However, new strategies are needed to enhance responses. Here we have performed a detailed analysis of the effects of BTKi on B-cell receptor (BCR)-induced signalling using primary malignant cells from CLL patients and B-lymphoma cell lines. Although BTK is considered as a key activator of PLCγ2, BTKi (ibrutinib and acalabrutinib) failed to fully inhibit calcium responses in CLL samples with strong BCR signalling capacity. This BTKi-resistant calcium signalling was sufficient to engage downstream calcium-dependent transcription and suppress CLL cell apoptosis and was entirely independent of BTK and not just its kinase activity as similar results were obtained using a BTK-degrading PROTAC. BTK-independent calcium signalling was also observed in two B-lymphoma cell lines where BTKi had little effect on the initial phase of the calcium response but did accelerate the subsequent decline in intracellular calcium. In contrast to BTKi, calcium responses were completely blocked by inhibition of SYK in CLL and lymphoma cells. Engagement of BTK-independent calcium responses was associated with BTK-independent phosphorylation of PLCγ2 on Y
753 and Y759 in both CLL and lymphoma cells. Moreover, in CLL samples, inhibition of RAC, which can mediate BTK-independent activation of PLCγ2, cooperated with ibrutinib to suppress calcium responses. BTK-independent calcium signalling may limit the effectiveness of BTKi to suppress BCR signalling responses and our results suggest inhibition of SYK or dual inhibition of BTK and RAC as alternative strategies to strengthen pathway blockade., (Copyright © 2022. Published by Elsevier Inc.)- Published
- 2022
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8. Fixed-Duration Ibrutinib-Venetoclax in Patients with Chronic Lymphocytic Leukemia and Comorbidities.
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Kater AP, Owen C, Moreno C, Follows G, Munir T, Levin MD, Benjamini O, Janssens A, Osterborg A, Robak T, Simkovic M, Stevens D, Voloshin S, Vorobyev V, Ysebaert L, Qin R, Steele AJ, Schuier N, Baeten K, Caces DB, and Niemann CU
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- Humans, Aged, Male, Female, Middle Aged, Adult, Comorbidity, Aged, 80 and over, Pyrimidines therapeutic use, Pyrimidines adverse effects, Pyrimidines administration & dosage, Pyrazoles therapeutic use, Pyrazoles adverse effects, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Antineoplastic Combined Chemotherapy Protocols adverse effects, Young Adult, Antineoplastic Agents therapeutic use, Antineoplastic Agents adverse effects, Leukemia, Lymphocytic, Chronic, B-Cell drug therapy, Leukemia, Lymphocytic, Chronic, B-Cell mortality, Adenine analogs & derivatives, Piperidines therapeutic use, Piperidines adverse effects
- Abstract
BACKGROUND: GLOW is a phase 3 trial evaluating the efficacy and safety of ibrutinib-venetoclax in older patients and/or those with comorbidities with previously untreated chronic lymphocytic leukemia (CLL). METHODS: We randomly assigned (1:1) patients 65 years of age or older or those 18 to 64 years of age who also had a Cumulative Illness Rating Scale (CIRS) score greater than 6 (CIRS scores range from 0 to 56, with higher scores indicating more impaired function of organ systems) or creatinine clearance of less than 70 ml/min, to ibrutinib-venetoclax (3 cycles ibrutinib lead-in, then 12 cycles ibrutinib-venetoclax) or chlorambucil-obinutuzumab (6 cycles). The primary end point was progression-free survival (PFS) assessed by an independent review committee. Secondary end points included undetectable minimal residual disease (uMRD), response rates, and safety. RESULTS: This study enrolled 211 patients, with 106 randomly assigned to ibrutinib-venetoclax and 105 to chlorambucil-obinutuzumab. With a median follow-up of 27.7 months, there were 22 PFS events for ibrutinib-venetoclax and 67 events for chlorambucil-obinutuzumab. PFS was significantly longer for ibrutinib-venetoclax than for chlorambucil-obinutuzumab (hazard ratio, 0.216; 95% confidence interval [CI], 0.131 to 0.357; P<0.001). The improvement in PFS with ibrutinib-venetoclax was consistent across predefined subgroups, including patients 65 years of age or older or with a CIRS score greater than 6. The best uMRD rate in bone marrow by next-generation sequencing was significantly higher for ibrutinib-venetoclax (55.7%) than for chlorambucil-obinutuzumab (21.0%; P<0.001). The proportion of patients with sustained uMRD in peripheral blood from 3 to 12 months after end of treatment was 84.5% for ibrutinib-venetoclax and 29.3% for chlorambucil-obinutuzumab. Four patients treated with ibrutinib-venetoclax required subsequent therapy compared with 27 patients receiving chlorambucil-obinutuzumab (hazard ratio, 0.143; 95% CI, 0.050 to 0.410). Adverse events grade 3 or greater occurred for 80 (75.5%) and 73 (69.5%) patients receiving ibrutinib-venetoclax and chlorambucil-obinutuzumab, respectively, with neutropenia being most common in both arms (37 [34.9%] and 52 [49.5%]). There were 11 (10.4%) and 12 (11.4%) all-cause deaths in the ibrutinib-venetoclax and chlorambucil-obinutuzumab arms, respectively. CONCLUSIONS: Ibrutinib-venetoclax, an all-oral, once-daily, fixed-duration combination, demonstrated superior PFS and deeper and better sustained responses versus chlorambucil-obinutuzumab as first-line CLL treatment in older patients and/or those with comorbidities. (Funded by Janssen Research & Development, LLC, and Pharmacyclics; ClinicalTrials.gov number, NCT03462719.)
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- 2022
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9. Phagocytosing with TP53 and extracellular vesicles.
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Steele AJ
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- B7-H1 Antigen, Humans, Macrophages, Phagocytosis, Tumor Suppressor Protein p53 genetics, Extracellular Vesicles, Neoplasms
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- 2022
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10. B-cell receptor signaling induces proteasomal degradation of PDCD4 via MEK1/2 and mTORC1 in malignant B cells.
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Taylor J, Wilmore S, Marriot S, Rogers-Broadway KR, Fell R, Minton AR, Branch T, Ashton-Key M, Coldwell M, Stevenson FK, Forconi F, Steele AJ, Packham G, and Yeomans A
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- Apoptosis Regulatory Proteins metabolism, Humans, Mechanistic Target of Rapamycin Complex 1 metabolism, Proto-Oncogene Proteins c-akt metabolism, RNA-Binding Proteins metabolism, Receptors, Antigen, B-Cell genetics, Receptors, Antigen, B-Cell metabolism, Receptors, Antigen, B-Cell therapeutic use, Signal Transduction, Leukemia, Lymphocytic, Chronic, B-Cell genetics
- Abstract
B-cell receptor (BCR) signaling plays a major role in the pathogenesis of B-cell malignancies and is an established target for therapy, including in chronic lymphocytic leukemia cells (CLL), the most common B-cell malignancy. We previously demonstrated that activation of BCR signaling in primary CLL cells downregulated expression of PDCD4, an inhibitor of the translational initiation factor eIF4A and a potential tumor suppressor in lymphoma. Regulation of the PDCD4/eIF4A axis appeared to be important for expression of the MYC oncoprotein as MYC mRNA translation was increased following BCR stimulation and MYC protein induction was repressed by pharmacological inhibition of eIF4A. Here we show that MYC expression is also associated with PDCD4 down-regulation in CLL cells in vivo and characterize the signaling pathways that mediate BCR-induced PDCD4 down-regulation in CLL and lymphoma cells. PDCD4 downregulation was mediated by proteasomal degradation as it was inhibited by proteasome inhibitors in both primary CLL cells and B-lymphoma cell lines. In lymphoma cells, PDCD4 degradation was predominantly dependent on signaling via the AKT pathway. By contrast, in CLL cells, both ERK and AKT pathways contributed to PDCD4 down-regulation and dual inhibition using ibrutinib with either MEK1/2 or mTORC1 inhibition was required to fully reverse PDCD4 down-regulation. Consistent with this, dual inhibition of BTK with MEK1/2 or mTORC1 resulted in the strongest inhibition of BCR-induced MYC expression. This study provides important new insight into the regulation of mRNA translation in B-cell malignancies and a rationale for combinations of kinase inhibitors to target translation control and MYC expression., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2022
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11. B-cell receptor dependent phagocytosis and presentation of particulate antigen by chronic lymphocytic leukemia cells.
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Minton AR, Smith LD, Bryant DJ, Strefford JC, Forconi F, Stevenson FK, Tumbarello DA, James E, Løset GÅ, Munthe LA, Steele AJ, and Packham G
- Abstract
Aim: T-helper cells could play an important role in the pathogenesis of chronic lymphocytic leukemia (CLL), a common B-cell neoplasm. Although CLL cells can present soluble antigens targeted from the B-cell receptor to T-helper cells via major histocompatibility complex (MHC) class II, antigens recognized by some CLL cells may be encountered in a particulate form. Here the ability of CLL cells to internalize and present anti-immunoglobulin M (IgM) beads as a model for the interaction of CLL cells with particulate antigens was investigated., Methods: The effect of anti-IgM beads on antigen presentation pathways was analyzed using RNA-seq and internalization of anti-IgM beads by primary CLL cells was investigated using confocal microscopy and flow cytometry. Antigen presentation was investigated by analyzing activation of a T-cell line expressing a T-cell receptor specific for a peptide derived from mouse κ light chains after incubating CLL cells with a mouse κ light chain-containing anti-IgM monoclonal antibody. Kinase inhibitors were used to characterize the pathways mediating internalization and antigen presentation., Results: Stimulation of surface IgM of CLL cells increased expression of the antigen presentation machinery and CLL cells were able to phagocytose anti-IgM beads. Internalization of anti-IgM beads was associated with MHC class II-restricted activation of cognate T-helper cells. Antigen presentation by CLL cells was dependent on activity of spleen tyrosine kinase (SYK) and phosphatidylinositol 3-kinase delta (PI3Kδ) but was unaffected by inhibitors of Bruton's tyrosine kinase (BTK)., Conclusions: CLL cells can internalize and present antigen from anti-IgM beads. This capacity of CLL cells may be particularly important for recruitment of T-cell help in vivo in response to particulate antigens., Competing Interests: Conflicts of interest The authors declare that they have no conflicts of interest.
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- 2022
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12. Kinobead Profiling Reveals Reprogramming of BCR Signaling in Response to Therapy within Primary CLL Cells.
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Linley AJ, Karydis LI, Mondru AK, D'Avola A, Al Shmrany H, Cicconi S, Griffin R, Forconi F, Pettitt AR, Kalakonda N, Rawstron AC, Hillmen P, Steele AJ, MacEwan DJ, Packham G, Prior IA, and Slupsky JR
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- Cytological Techniques methods, Humans, Microspheres, Protein Kinase Inhibitors, Tumor Cells, Cultured, B-Lymphocytes physiology, Leukemia, Lymphocytic, Chronic, B-Cell etiology, Leukemia, Lymphocytic, Chronic, B-Cell pathology, Signal Transduction physiology
- Abstract
Purpose: B-cell receptor (BCR) signaling is critical for the pathogenesis of chronic lymphocytic leukemia (CLL), promoting both malignant cell survival and disease progression. Although vital, understanding of the wider signaling network associated with malignant BCR stimulation is poor. This is relevant with respect to potential changes in response to therapy, particularly involving kinase inhibitors. In the current study, we describe a novel high-resolution approach to investigate BCR signaling in primary CLL cells and track the influence of therapy on signaling response., Experimental Design: A kinobead/mass spectrometry-based protocol was used to study BCR signaling in primary CLL cells. Longitudinal analysis of samples donated by clinical trial patients was used to investigate the impact of chemoimmunotherapy and ibrutinib on signaling following surface IgM engagement. Complementary Nanostring and immunoblotting analysis was used to verify our findings., Results: Our protocol isolated a unique, patient-specific signature of over 30 kinases from BCR-stimulated CLL cells. This signature was associated with 13 distinct Kyoto Encyclopedia of Genes and Genomes pathways and showed significant change in cells from treatment-naïve patients compared with those from patients who had previously undergone therapy. This change was validated by longitudinal analysis of clinical trials samples where BCR-induced kinome responses in CLL cells altered between baseline and disease progression in patients failing chemoimmunotherapy and between baseline and treatment in patients taking ibrutinib., Conclusions: These data comprise the first comprehensive proteomic investigation of the BCR signaling response within CLL cells and reveal unique evidence that these cells undergo adaptive reprogramming of this signaling in response to therapy., (©2021 The Authors; Published by the American Association for Cancer Research.)
- Published
- 2021
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13. Targeted inhibition of eIF4A suppresses B-cell receptor-induced translation and expression of MYC and MCL1 in chronic lymphocytic leukemia cells.
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Wilmore S, Rogers-Broadway KR, Taylor J, Lemm E, Fell R, Stevenson FK, Forconi F, Steele AJ, Coldwell M, Packham G, and Yeomans A
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- Antibodies, Anti-Idiotypic pharmacology, Benzofurans pharmacology, Cells, Cultured, Eukaryotic Initiation Factor-4A antagonists & inhibitors, Humans, Leukemia, Lymphocytic, Chronic, B-Cell metabolism, Leukocytes, Mononuclear cytology, Leukocytes, Mononuclear drug effects, Leukocytes, Mononuclear metabolism, Myeloid Cell Leukemia Sequence 1 Protein genetics, Protein Biosynthesis drug effects, Proto-Oncogene Proteins c-myc genetics, RNA Stability drug effects, RNA, Messenger metabolism, Signal Transduction drug effects, Triterpenes pharmacology, Eukaryotic Initiation Factor-4A metabolism, Leukemia, Lymphocytic, Chronic, B-Cell pathology, Myeloid Cell Leukemia Sequence 1 Protein metabolism, Proto-Oncogene Proteins c-myc metabolism, Receptors, Antigen, B-Cell metabolism
- Abstract
Signaling via the B-cell receptor (BCR) is a key driver and therapeutic target in chronic lymphocytic leukemia (CLL). BCR stimulation of CLL cells induces expression of eIF4A, an initiation factor important for translation of multiple oncoproteins, and reduces expression of PDCD4, a natural inhibitor of eIF4A, suggesting that eIF4A may be a critical nexus controlling protein expression downstream of the BCR in these cells. We, therefore, investigated the effect of eIF4A inhibitors (eIF4Ai) on BCR-induced responses. We demonstrated that eIF4Ai (silvestrol and rocaglamide A) reduced anti-IgM-induced global mRNA translation in CLL cells and also inhibited accumulation of MYC and MCL1, key drivers of proliferation and survival, respectively, without effects on upstream signaling responses (ERK1/2 and AKT phosphorylation). Analysis of normal naïve and non-switched memory B cells, likely counterparts of the two main subsets of CLL, demonstrated that basal RNA translation was higher in memory B cells, but was similarly increased and susceptible to eIF4Ai-mediated inhibition in both. We probed the fate of MYC mRNA in eIF4Ai-treated CLL cells and found that eIF4Ai caused a profound accumulation of MYC mRNA in anti-IgM treated cells. This was mediated by MYC mRNA stabilization and was not observed for MCL1 mRNA. Following drug wash-out, MYC mRNA levels declined but without substantial MYC protein accumulation, indicating that stabilized MYC mRNA remained blocked from translation. In conclusion, BCR-induced regulation of eIF4A may be a critical signal-dependent nexus for therapeutic attack in CLL and other B-cell malignancies, especially those dependent on MYC and/or MCL1., (© 2021. The Author(s).)
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- 2021
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14. System of Psychological Support Based on Positive Suggestions to the Critically Ill Using ICU Doulas.
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Karnatovskaia LV, Schultz JM, Niven AS, Steele AJ, Baker BA, Philbrick KL, Del Valle KT, Johnson KR, Gajic O, and Varga K
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Surviving critical illness often creates a lasting psychological impact, including depression, anxiety, and post-traumatic stress. Memories of frightening and delusional experiences are the largest potentially modifiable risk factor, but currently, there is no proven intervention to improve these inciting factors. Psychological support based on positive suggestion is a psychotherapeutic approach that can be provided even to patients in altered cognitive states and is therefore a viable psychotherapy intervention throughout the ICU stay. Traditional ICU care team members have limited time and training to provide such psychological support to patients. Doulas are trained supportive companions who have been effectively used to provide patient advocacy and emotional support in other clinical settings and may address this need. Our aim was to train and implement a psychological support based on positive suggestion program for the critically ill using doulas, and measure acceptance of this intervention through stakeholder feedback., Methods: Doula training included three objectives: an introduction to ICU practice structure and policies; education about fundamental aspects of critical care conditions and procedures; and didactic and hands-on learning experiences in effective use of psychological support based on positive suggestion in the critically ill. Doulas were evaluated at the end of their training and during subsequent clinical activities using competency-based assessments as well as through survey-based questions and interviews with key stakeholders., Results: The ICU doulas performed psychological support based on positive suggestion on 43 critically ill patients in the ICU setting. Stakeholder feedback from nurses, patients, and patient families was positive. The majority (28/32) of surveyed bedside ICU nurses reported that the doulas' involvement was helpful for both patients and nurses alike. All interviewed family members offered positive comments about the ICU doula presence and of the 40 patients who recalled the intervention 37 found it comforting., Conclusions: Our program successfully trained two doulas to work effectively in the ICU setting performing patient-centered psychological support based on positive suggestion interventions. Their training improved their skill sets and was reported as beneficial by patients, families, and critical care nursing. This training program offers a proof of concept that could be applied in other medical centers, bringing doulas more commonly into the ICU practice to help humanize the experience for patients, families, and medical teams., Competing Interests: The authors have disclosed that they do not have any potential conflicts of interest., (Copyright © 2021 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the Society of Critical Care Medicine.)
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- 2021
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15. Clinical significance of TP53, BIRC3, ATM and MAPK-ERK genes in chronic lymphocytic leukaemia: data from the randomised UK LRF CLL4 trial.
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Blakemore SJ, Clifford R, Parker H, Antoniou P, Stec-Dziedzic E, Larrayoz M, Davis Z, Kadalyayil L, Colins A, Robbe P, Vavoulis D, Forster J, Carr L, Morilla R, Else M, Bryant D, McCarthy H, Walewska RJ, Steele AJ, Chan J, Speight G, Stankovic T, Cragg MS, Catovsky D, Oscier DG, Rose-Zerilli MJJ, Schuh A, and Strefford JC
- Subjects
- Antineoplastic Combined Chemotherapy Protocols therapeutic use, Cohort Studies, Cyclophosphamide administration & dosage, Extracellular Signal-Regulated MAP Kinases genetics, Follow-Up Studies, Gene Expression Regulation, Neoplastic, Humans, Leukemia, Lymphocytic, Chronic, B-Cell drug therapy, Leukemia, Lymphocytic, Chronic, B-Cell genetics, Leukemia, Lymphocytic, Chronic, B-Cell pathology, Prognosis, Survival Rate, Vidarabine administration & dosage, Vidarabine analogs & derivatives, Ataxia Telangiectasia Mutated Proteins genetics, Baculoviral IAP Repeat-Containing 3 Protein genetics, Biomarkers, Tumor genetics, Leukemia, Lymphocytic, Chronic, B-Cell mortality, MAP Kinase Signaling System genetics, Mutation, Tumor Suppressor Protein p53 genetics
- Abstract
Despite advances in chronic lymphocytic leukaemia (CLL) treatment, globally chemotherapy remains a central treatment modality, with chemotherapy trials representing an invaluable resource to explore disease-related/genetic features contributing to long-term outcomes. In 499 LRF CLL4 cases, a trial with >12 years follow-up, we employed targeted resequencing of 22 genes, identifying 623 mutations. After background mutation rate correction, 11/22 genes were recurrently mutated at frequencies between 3.6% (NFKBIE) and 24% (SF3B1). Mutations beyond Sanger resolution (<12% VAF) were observed in all genes, with KRAS mutations principally composed of these low VAF variants. Firstly, employing orthogonal approaches to confirm <12% VAF TP53 mutations, we assessed the clinical impact of TP53 clonal architecture. Whilst ≥ 12% VAF TP53mut cases were associated with reduced PFS and OS, we could not demonstrate a difference between <12% VAF TP53 mutations and either wild type or ≥12% VAF TP53mut cases. Secondly, we identified biallelic BIRC3 lesions (mutation and deletion) as an independent marker of inferior PFS and OS. Finally, we observed that mutated MAPK-ERK genes were independent markers of poor OS in multivariate survival analysis. In conclusion, our study supports using targeted resequencing of expanded gene panels to elucidate the prognostic impact of gene mutations.
- Published
- 2020
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16. Development of PROTACs to address clinical limitations associated with BTK-targeted kinase inhibitors.
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Arthur R, Valle-Argos B, Steele AJ, and Packham G
- Abstract
Chronic lymphocytic leukemia is a common form of leukemia and is dependent on growth-promoting signaling via the B-cell receptor. The Bruton tyrosine kinase (BTK) is an important mediator of B-cell receptor signaling and the irreversible BTK inhibitor ibrutinib can trigger dramatic clinical responses in treated patients. However, emergence of resistance and toxicity are major limitations which lead to treatment discontinuation. There remains, therefore, a clear need for new therapeutic options. In this review, we discuss recent progress in the development of BTK-targeted proteolysis targeting chimeras (PROTACs) describing how such agents may provide advantages over ibrutinib and highlighting features of PROTACs that are important for the development of effective BTK degrading agents. Overall, PROTACs appear to be an exciting new approach to target BTK. However, development is at a very early stage and considerable progress is required to refine these agents and optimize their drug-like properties before progression to clinical testing., Competing Interests: Conflicts of interest The authors declare that they have no conflicts of interest.
- Published
- 2020
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17. Preclinical Evaluation of a Novel SHIP1 Phosphatase Activator for Inhibition of PI3K Signaling in Malignant B Cells.
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Lemm EA, Valle-Argos B, Smith LD, Richter J, Gebreselassie Y, Carter MJ, Karolova J, Svaton M, Helman K, Weston-Bell NJ, Karydis L, Williamson CT, Lenz G, Pettigrew J, Harwig C, Stevenson FK, Cragg M, Forconi F, Steele AJ, Cross J, Mackenzie L, Klener P, and Packham G
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- Animals, Apoptosis drug effects, Cell Line, Tumor, Female, Humans, Leukemia, Lymphocytic, Chronic, B-Cell metabolism, Leukemia, Lymphocytic, Chronic, B-Cell pathology, Lymphoma, Large B-Cell, Diffuse metabolism, Lymphoma, Large B-Cell, Diffuse pathology, Mice, Mice, Inbred NOD, Phosphatidylinositol 3-Kinases chemistry, Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases genetics, Signal Transduction, Xenograft Model Antitumor Assays, Antineoplastic Agents pharmacology, Enzyme Activators pharmacology, Leukemia, Lymphocytic, Chronic, B-Cell drug therapy, Lymphoma, Large B-Cell, Diffuse drug therapy, Phosphatidylinositol 3-Kinases metabolism, Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases metabolism, Sesquiterpenes pharmacology
- Abstract
Purpose: PI3K signaling is a common feature of B-cell neoplasms, including chronic lymphocytic leukemia (CLL) and diffuse large B-cell lymphoma (DLBCL), and PI3K inhibitors have been introduced into the clinic. However, there remains a clear need to develop new strategies to target PI3K signaling. PI3K activity is countered by Src homology domain 2-containing inositol-5'-phosphatase 1 (SHIP1) and, here, we have characterized the activity of a novel SHIP1 activator, AQX-435, in preclinical models of B-cell malignancies., Experimental Design: In vitro activity of AQX-435 was evaluated using primary CLL cells and DLBCL-derived cell lines. In vivo activity of AQX-435, alone or in combination with the Bruton's tyrosine kinase (BTK) inhibitor ibrutinib, was assessed using DLBCL cell line and patient-derived xenograft models., Results: Pharmacologic activation of SHIP1 using AQX-435 was sufficient to inhibit anti-IgM-induced PI3K-mediated signaling, including induction of AKT phosphorylation and MYC expression, without effects on upstream SYK phosphorylation. AQX-435 also cooperated with the BTK inhibitor ibrutinib to enhance inhibition of anti-IgM-induced AKT phosphorylation. AQX-435 induced caspase-dependent apoptosis of CLL cells preferentially as compared with normal B cells, and overcame in vitro survival-promoting effects of microenvironmental stimuli. Finally, AQX-435 reduced AKT phosphorylation and growth of DLBCL in vivo and cooperated with ibrutinib for tumor growth inhibition., Conclusions: Our results using AQX-435 demonstrate that SHIP1 activation may be an effective novel therapeutic strategy for treatment of B-cell neoplasms, alone or in combination with ibrutinib., (©2019 American Association for Cancer Research.)
- Published
- 2020
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18. BCR signaling contributes to autophagy regulation in chronic lymphocytic leukemia.
- Author
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Smith LD, Minton AR, Blunt MD, Karydis LI, Dutton DA, Rogers-Broadway KR, Dobson R, Liu R, Norster F, Hogg E, Ashton-Key M, Strefford JC, Jia L, Efremov DG, Helgason GV, Johnson PWM, Stevenson FK, Forconi F, Cragg MS, Tumbarello DA, Packham G, and Steele AJ
- Subjects
- Humans, Autophagy physiology, Leukemia, Lymphocytic, Chronic, B-Cell metabolism, Leukemia, Lymphocytic, Chronic, B-Cell pathology, Receptors, Antigen, B-Cell metabolism, Signal Transduction physiology
- Published
- 2020
- Full Text
- View/download PDF
19. Clinical significance of DNA methylation in chronic lymphocytic leukemia patients: results from 3 UK clinical trials.
- Author
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Wojdacz TK, Amarasinghe HE, Kadalayil L, Beattie A, Forster J, Blakemore SJ, Parker H, Bryant D, Larrayoz M, Clifford R, Robbe P, Davis ZA, Else M, Howard DR, Stamatopoulos B, Steele AJ, Rosenquist R, Collins A, Pettitt AR, Hillmen P, Plass C, Schuh A, Catovsky D, Oscier DG, Rose-Zerilli MJJ, Oakes CC, and Strefford JC
- Subjects
- Adult, Aged, Aged, 80 and over, Chromosome Aberrations, Computational Biology methods, Epigenesis, Genetic, Epigenomics methods, Female, Gene Expression Profiling, Humans, Immunoglobulin Heavy Chains genetics, Leukemia, Lymphocytic, Chronic, B-Cell mortality, Leukemia, Lymphocytic, Chronic, B-Cell therapy, Male, Middle Aged, Mutation, Neoplasm Staging, Prognosis, Proportional Hazards Models, DNA Methylation, Gene Expression Regulation, Leukemic, Leukemia, Lymphocytic, Chronic, B-Cell diagnosis, Leukemia, Lymphocytic, Chronic, B-Cell genetics
- Abstract
Chronic lymphocytic leukemia patients with mutated immunoglobulin heavy-chain genes (IGHV-M), particularly those lacking poor-risk genomic lesions, often respond well to chemoimmunotherapy (CIT). DNA methylation profiling can subdivide early-stage patients into naive B-cell-like CLL (n-CLL), memory B-cell-like CLL (m-CLL), and intermediate CLL (i-CLL), with differing times to first treatment and overall survival. However, whether DNA methylation can identify patients destined to respond favorably to CIT has not been ascertained. We classified treatment-naive patients (n = 605) from 3 UK chemo and CIT clinical trials into the 3 epigenetic subgroups, using pyrosequencing and microarray analysis, and performed expansive survival analysis. The n-CLL, i-CLL, and m-CLL signatures were found in 80% (n = 245/305), 17% (53/305), and 2% (7/305) of IGHV-unmutated (IGHV-U) cases, respectively, and in 9%, (19/216), 50% (108/216), and 41% (89/216) of IGHV-M cases, respectively. Multivariate Cox proportional analysis identified m-CLL as an independent prognostic factor for overall survival (hazard ratio [HR], 0.46; 95% confidence interval [CI], 0.24-0.87; P = .018) in CLL4, and for progression-free survival (HR, 0.25; 95% CI, 0.10-0.57; P = .002) in ARCTIC and ADMIRE patients. The analysis of epigenetic subgroups in patients entered into 3 first-line UK CLL trials identifies m-CLL as an independent marker of prolonged survival and may aid in the identification of patients destined to demonstrate prolonged survival after CIT., (© 2019 by The American Society of Hematology.)
- Published
- 2019
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20. Autophagy inhibition-mediated epithelial-mesenchymal transition augments local myofibroblast differentiation in pulmonary fibrosis.
- Author
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Hill C, Li J, Liu D, Conforti F, Brereton CJ, Yao L, Zhou Y, Alzetani A, Chee SJ, Marshall BG, Fletcher SV, Hancock D, Ottensmeier CH, Steele AJ, Downward J, Richeldi L, Lu X, Davies DE, Jones MG, and Wang Y
- Subjects
- A549 Cells, Aging genetics, Aging pathology, Alveolar Epithelial Cells metabolism, Alveolar Epithelial Cells pathology, Autophagy genetics, Cell Differentiation genetics, Fibroblasts metabolism, Humans, Idiopathic Pulmonary Fibrosis metabolism, Idiopathic Pulmonary Fibrosis pathology, Lung metabolism, Lung pathology, Lung Neoplasms genetics, Lung Neoplasms pathology, Myofibroblasts metabolism, Myofibroblasts pathology, Primary Cell Culture, Risk Factors, Transcription Factors, Epithelial-Mesenchymal Transition genetics, Idiopathic Pulmonary Fibrosis genetics, Sequestosome-1 Protein genetics, Snail Family Transcription Factors genetics, Transcription Factor RelA genetics
- Abstract
Idiopathic pulmonary fibrosis (IPF), the prototypic progressive fibrotic interstitial lung disease, is thought to be a consequence of repetitive micro-injuries to an ageing, susceptible alveolar epithelium. Ageing is a risk factor for IPF and incidence has been demonstrated to increase with age. Decreased (macro)autophagy with age has been reported extensively in a variety of systems and diseases, including IPF. However, it is undetermined whether the role of faulty autophagy is causal or coincidental in the context of IPF. Here, we report that in alveolar epithelial cells inhibition of autophagy promotes epithelial-mesenchymal transition (EMT), a process implicated in embryonic development, wound healing, cancer metastasis and fibrosis. We further demonstrate that this is attained, at least in part, by increased p62/SQSTM1 expression that promotes p65/RELA mediated-transactivation of an EMT transcription factor, Snail2 (SNAI2), which not only controls EMT but also regulates the production of locally acting profibrogenic mediators. Our data suggest that reduced autophagy induces EMT of alveolar epithelial cells and can contribute to fibrosis via aberrant epithelial-fibroblast crosstalk.
- Published
- 2019
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21. Ibrutinib Therapy Releases Leukemic Surface IgM from Antigen Drive in Chronic Lymphocytic Leukemia Patients.
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Drennan S, Chiodin G, D'Avola A, Tracy I, Johnson PW, Trentin L, Steele AJ, Packham G, Stevenson FK, and Forconi F
- Subjects
- Adenine analogs & derivatives, Humans, Immunoglobulin M, Piperidines, Protein-Tyrosine Kinases antagonists & inhibitors, Pyrazoles, Pyrimidines, Leukemia, Lymphocytic, Chronic, B-Cell
- Abstract
Purpose: In chronic lymphocytic leukemia (CLL), disease progression associates with surface IgM (sIgM) levels and signaling capacity. These are variably downmodulated in vivo and recover in vitro , suggesting a reversible influence of tissue-located antigen. Therapeutic targeting of sIgM function via ibrutinib, an inhibitor of Bruton tyrosine kinase (BTK), causes inhibition and tumor cell redistribution into the blood, with significant clinical benefit. Circulating CLL cells persist in an inhibited state, offering a tool to investigate the effects of drug on BTK-inhibited sIgM., Experimental Design: We investigated the consequences of ibrutinib therapy on levels and function of sIgM in circulating leukemic cells of patients with CLL., Results: At week 1, there was a significant increase of sIgM expression (64% increase from pretherapy) on CLL cells either recently released from tissue or persisting in blood. In contrast, surface IgD (sIgD) and a range of other receptors did not change. SIgM levels remained higher than pretherapy in the following 3 months despite gradual cell size reduction and ongoing autophagy and apoptotic activity. Conversely, IgD and other receptors did not increase and gradually declined. Recovered sIgM was fully N-glycosylated, another feature of escape from antigen, and expression did not increase further during culture in vitro . The sIgM was fully capable of mediating phosphorylation of SYK, which lies upstream of BTK in the B-cell receptor pathway., Conclusions: This specific IgM increase in patients underpins the key role of tissue-based engagement with antigen in CLL, confirms the inhibitory action of ibrutinib, and reveals dynamic adaptability of CLL cells to precision monotherapy. See related commentary by Burger, p. 2372 ., (©2018 American Association for Cancer Research.)
- Published
- 2019
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22. Ex-Vivo Signal Transduction Studies in Chronic Lymphocytic Leukemia.
- Author
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Rogers-Broadway KR, Karydis LI, Dobson RC, and Steele AJ
- Subjects
- B-Lymphocytes metabolism, Blotting, Western instrumentation, Electrophoresis, Polyacrylamide Gel instrumentation, Electrophoresis, Polyacrylamide Gel methods, Flow Cytometry instrumentation, Gene Expression Regulation, Leukemic, Humans, Receptors, Antigen, B-Cell metabolism, Blotting, Western methods, Flow Cytometry methods, Leukemia, Lymphocytic, Chronic, B-Cell pathology, Signal Transduction
- Abstract
Microenvironmental signaling is pivotal to chronic lymphocytic leukemia (CLL) pathology; therefore understanding how to investigate this pathway by both protein and chemical methods is crucial if we are to investigate and correlate biological changes with therapeutic responses in patients. Herein, we describe the use of western blotting also referred to as immunoblotting as a method that can semiquantitatively evaluate changes in protein expression following receptor engagement; this includes B cell receptor (BCR) signaling following stimulation with anti-IgM (Blunt et al. Clin Cancer Res 23(9):2313-2324, 2017). It is important to note that immunoblotting should always be combined with other quantitative methods such as flow cytometry to confirm activation of these signaling pathways (Aguilar-Hernandez et al. Blood 127(24):3015-3025, 2016).
- Published
- 2019
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23. Machine learning models in electronic health records can outperform conventional survival models for predicting patient mortality in coronary artery disease.
- Author
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Steele AJ, Denaxas SC, Shah AD, Hemingway H, and Luscombe NM
- Subjects
- Adult, Aged, Aged, 80 and over, Cohort Studies, Data Interpretation, Statistical, Female, Humans, Male, Middle Aged, Models, Biological, Prognosis, Coronary Artery Disease diagnosis, Coronary Artery Disease mortality, Diagnosis, Computer-Assisted methods, Electronic Health Records, Machine Learning, Survival Analysis
- Abstract
Prognostic modelling is important in clinical practice and epidemiology for patient management and research. Electronic health records (EHR) provide large quantities of data for such models, but conventional epidemiological approaches require significant researcher time to implement. Expert selection of variables, fine-tuning of variable transformations and interactions, and imputing missing values are time-consuming and could bias subsequent analysis, particularly given that missingness in EHR is both high, and may carry meaning. Using a cohort of 80,000 patients from the CALIBER programme, we compared traditional modelling and machine-learning approaches in EHR. First, we used Cox models and random survival forests with and without imputation on 27 expert-selected, preprocessed variables to predict all-cause mortality. We then used Cox models, random forests and elastic net regression on an extended dataset with 586 variables to build prognostic models and identify novel prognostic factors without prior expert input. We observed that data-driven models used on an extended dataset can outperform conventional models for prognosis, without data preprocessing or imputing missing values. An elastic net Cox regression based with 586 unimputed variables with continuous values discretised achieved a C-index of 0.801 (bootstrapped 95% CI 0.799 to 0.802), compared to 0.793 (0.791 to 0.794) for a traditional Cox model comprising 27 expert-selected variables with imputation for missing values. We also found that data-driven models allow identification of novel prognostic variables; that the absence of values for particular variables carries meaning, and can have significant implications for prognosis; and that variables often have a nonlinear association with mortality, which discretised Cox models and random forests can elucidate. This demonstrates that machine-learning approaches applied to raw EHR data can be used to build models for use in research and clinical practice, and identify novel predictive variables and their effects to inform future research., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2018
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24. Roring ahead with DOCK2.
- Author
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Steele AJ
- Subjects
- GTPase-Activating Proteins, Guanine Nucleotide Exchange Factors, Humans, Receptor Tyrosine Kinase-like Orphan Receptors, Wnt-5a Protein, rac1 GTP-Binding Protein, Leukemia, Lymphocytic, Chronic, B-Cell
- Abstract
Competing Interests: Conflict-of-interest disclosure: The author declares no competing financial interests.
- Published
- 2018
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25. Proteomics Profiling of CLL Versus Healthy B-cells Identifies Putative Therapeutic Targets and a Subtype-independent Signature of Spliceosome Dysregulation.
- Author
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Johnston HE, Carter MJ, Larrayoz M, Clarke J, Garbis SD, Oscier D, Strefford JC, Steele AJ, Walewska R, and Cragg MS
- Subjects
- Humans, Proteomics, Spliceosomes, B-Lymphocytes metabolism, Leukemia, Lymphocytic, Chronic, B-Cell metabolism, Neoplasm Proteins metabolism
- Abstract
Chronic lymphocytic leukemia (CLL) is a heterogeneous B-cell cancer exhibiting a wide spectrum of disease courses and treatment responses. Molecular characterization of RNA and DNA from CLL cases has led to the identification of important driver mutations and disease subtypes, but the precise mechanisms of disease progression remain elusive. To further our understanding of CLL biology we performed isobaric labeling and mass spectrometry proteomics on 14 CLL samples, comparing them with B-cells from healthy donors (HDB). Of 8694 identified proteins, ∼6000 were relatively quantitated between all samples (q<0.01). A clear CLL signature, independent of subtype, of 544 significantly overexpressed proteins relative to HDB was identified, highlighting established hallmarks of CLL ( e.g. CD5, BCL2, ROR1 and CD23 overexpression). Previously unrecognized surface markers demonstrated overexpression ( e.g. CKAP4, PIGR, TMCC3 and CD75) and three of these (LAX1, CLEC17A and ATP2B4) were implicated in B-cell receptor signaling, which plays an important role in CLL pathogenesis. Several other proteins ( e.g. Wee1, HMOX1/2, HDAC7 and INPP5F) were identified with significant overexpression that also represent potential targets. Western blotting confirmed overexpression of a selection of these proteins in an independent cohort. mRNA processing machinery were broadly upregulated across the CLL samples. Spliceosome components demonstrated consistent overexpression ( p = 1.3 × 10
-21 ) suggesting dysregulation in CLL, independent of SF3B1 mutations. This study highlights the potential of proteomics in the identification of putative CLL therapeutic targets and reveals a subtype-independent protein expression signature in CLL., Competing Interests: Conflict of Interest Disclosure: M.S.C. is a retained consultant for Bioinvent and has performed educational and advisory roles for Baxalta. He has received research funding from Roche, Gilead and GSK. A.J.S. is a consultant and has also received research funding and honoraria from Portola Pharmaceuticals (USA) and Gilead (UK)., (© 2018 by The American Society for Biochemistry and Molecular Biology, Inc.)- Published
- 2018
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26. IL-10 production by CLL cells is enhanced in the anergic IGHV mutated subset and associates with reduced DNA methylation of the IL10 locus.
- Author
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Drennan S, D'Avola A, Gao Y, Weigel C, Chrysostomou E, Steele AJ, Zenz T, Plass C, Johnson PW, Williams AP, Packham G, Stevenson FK, Oakes CC, and Forconi F
- Subjects
- Humans, Interleukin-10 genetics, STAT3 Transcription Factor metabolism, Syk Kinase antagonists & inhibitors, Syk Kinase physiology, DNA Methylation, Immunoglobulin Heavy Chains genetics, Immunoglobulin Variable Region genetics, Interleukin-10 biosynthesis, Leukemia, Lymphocytic, Chronic, B-Cell immunology, Mutation
- Abstract
Chronic lymphocytic leukemias (CLLs) with unmutated (U-CLL) or mutated (M-CLL) IGHV have variable features of immunosuppression, possibly influenced by those CLL cells activated to produce interleukin 10 (IL-10). The two subsets differ in their levels of anergy, defined by low surface immunoglobulin M levels/signaling capacity, and in their DNA methylation profile, particularly variable in M-CLL. We have now found that levels of IL-10 produced by activated CLL cells were highly variable. Levels were higher in M-CLL than in U-CLL and correlated with anergy. DNA methylation analysis of IL10 locus revealed two previously uncharacterized 'variably methylated regions' (CLL-VMRs1/2) in the gene body, but similarly low methylation in the promoter of both U-CLL and M-CLL. CLL-VMR1/2 methylation was lower in M-CLL than in U-CLL and inversely correlated with IL-10 induction. A functional signal transducer and activator of transcription 3 (STAT3) binding site in CLL-VMR2 was confirmed by proximity ligation and luciferase assays, whereas inhibition of SYK-mediated STAT3 activation resulted in suppression of IL10. The data suggest epigenetic control of IL-10 production. Higher tumor load may compensate the reduced IL-10 production in U-CLL, accounting for clinical immunosuppression in both subsets. The observation that SYK inhibition also suppresses IL-10 provides a potential new rationale for therapeutic targeting and immunological rescue by SYK inhibitors in CLL.
- Published
- 2017
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27. STING Activation Reverses Lymphoma-Mediated Resistance to Antibody Immunotherapy.
- Author
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Dahal LN, Dou L, Hussain K, Liu R, Earley A, Cox KL, Murinello S, Tracy I, Forconi F, Steele AJ, Duriez PJ, Gomez-Nicola D, Teeling JL, Glennie MJ, Cragg MS, and Beers SA
- Subjects
- Animals, Antibodies, Monoclonal immunology, Female, Humans, Lymphoma metabolism, Mice, Mice, Inbred BALB C, Receptors, IgG immunology, Tumor Microenvironment immunology, Xenograft Model Antitumor Assays, Antibodies, Monoclonal pharmacology, Drug Resistance, Neoplasm immunology, Immunization, Passive methods, Lymphoma immunology, Lymphoma therapy, Membrane Proteins agonists, Membrane Proteins immunology
- Abstract
Tumors routinely attract and co-opt macrophages to promote their growth, angiogenesis, and metastasis. Macrophages are also the key effector cell for mAb therapies. Here we report that the tumor microenvironment creates an immunosuppressive signature on tumor-associated macrophages (TAM), which favors expression of inhibitory rather than activating Fcγ receptors (FcγR), thereby limiting the efficacy of mAb immunotherapy. We assessed a panel of TLR and STING agonists (a) for their ability to reprogram macrophages to a state optimal for mAb immunotherapy. Both STINGa and TLRa induced cytokine release, modulated FcγR expression, and augmented mAb-mediated tumor cell phagocytosis in vitro However, only STINGa reversed the suppressive FcγR profile in vivo , providing strong adjuvant effects to anti-CD20 mAb in murine models of lymphoma. Potent adjuvants like STINGa, which can improve FcγR activatory:inhibitory (A:I) ratios on TAM, are appealing candidates to reprogram TAM and curb tumor-mediated immunosuppression, thereby empowering mAb efficacy. Cancer Res; 77(13); 3619-31. ©2017 AACR ., (©2017 American Association for Cancer Research.)
- Published
- 2017
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28. Mycobacterium tuberculosis subverts negative regulatory pathways in human macrophages to drive immunopathology.
- Author
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Brace PT, Tezera LB, Bielecka MK, Mellows T, Garay D, Tian S, Rand L, Green J, Jogai S, Steele AJ, Millar TM, Sanchez-Elsner T, Friedland JS, Proud CG, and Elkington PT
- Subjects
- Animals, Humans, Macrophages microbiology, Matrix Metalloproteinase 1 genetics, Matrix Metalloproteinase 1 immunology, Mechanistic Target of Rapamycin Complex 1, Mice, Multiprotein Complexes genetics, Multiprotein Complexes immunology, Mycobacterium tuberculosis genetics, Mycobacterium tuberculosis physiology, Phosphatidylinositol 3-Kinases genetics, Phosphatidylinositol 3-Kinases immunology, TOR Serine-Threonine Kinases genetics, TOR Serine-Threonine Kinases immunology, Tuberculosis, Pulmonary genetics, Tuberculosis, Pulmonary microbiology, Tuberculosis, Pulmonary pathology, Macrophages immunology, Mycobacterium tuberculosis immunology, Tuberculosis, Pulmonary immunology
- Abstract
Tuberculosis remains a global pandemic and drives lung matrix destruction to transmit. Whilst pathways driving inflammatory responses in macrophages have been relatively well described, negative regulatory pathways are less well defined. We hypothesised that Mycobacterium tuberculosis (Mtb) specifically targets negative regulatory pathways to augment immunopathology. Inhibition of signalling through the PI3K/AKT/mTORC1 pathway increased matrix metalloproteinase-1 (MMP-1) gene expression and secretion, a collagenase central to TB pathogenesis, and multiple pro-inflammatory cytokines. In patients with confirmed pulmonary TB, PI3Kδ expression was absent within granulomas. Furthermore, Mtb infection suppressed PI3Kδ gene expression in macrophages. Interestingly, inhibition of the MNK pathway, downstream of pro-inflammatory p38 and ERK MAPKs, also increased MMP-1 secretion, whilst suppressing secretion of TH1 cytokines. Cross-talk between the PI3K and MNK pathways was demonstrated at the level of eIF4E phosphorylation. Mtb globally suppressed the MMP-inhibitory pathways in macrophages, reducing levels of mRNAs encoding PI3Kδ, mTORC-1 and MNK-1 via upregulation of miRNAs. Therefore, Mtb disrupts negative regulatory pathways at multiple levels in macrophages to drive a tissue-destructive phenotype that facilitates transmission.
- Published
- 2017
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29. The Dual Syk/JAK Inhibitor Cerdulatinib Antagonizes B-cell Receptor and Microenvironmental Signaling in Chronic Lymphocytic Leukemia.
- Author
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Blunt MD, Koehrer S, Dobson RC, Larrayoz M, Wilmore S, Hayman A, Parnell J, Smith LD, Davies A, Johnson PWM, Conley PB, Pandey A, Strefford JC, Stevenson FK, Packham G, Forconi F, Coffey GP, Burger JA, and Steele AJ
- Subjects
- Adenine analogs & derivatives, Antineoplastic Combined Chemotherapy Protocols administration & dosage, Apoptosis drug effects, B-Lymphocytes drug effects, Bridged Bicyclo Compounds, Heterocyclic administration & dosage, Flow Cytometry, Gene Expression Regulation, Neoplastic drug effects, Humans, Janus Kinase Inhibitors administration & dosage, Janus Kinases antagonists & inhibitors, Leukemia, Lymphocytic, Chronic, B-Cell genetics, Leukemia, Lymphocytic, Chronic, B-Cell pathology, Neoplasm Proteins genetics, Piperidines, Proto-Oncogene Proteins c-bcr antagonists & inhibitors, Proto-Oncogene Proteins c-bcr genetics, Pyrazoles administration & dosage, Signal Transduction drug effects, Sulfonamides administration & dosage, Syk Kinase antagonists & inhibitors, Tumor Microenvironment drug effects, Leukemia, Lymphocytic, Chronic, B-Cell drug therapy, Leukocytes, Mononuclear drug effects, Pyrimidines administration & dosage, Receptors, Antigen, B-Cell drug effects, Sulfones administration & dosage
- Abstract
Purpose: B-cell receptor (BCR)-associated kinase inhibitors, such as ibrutinib, have revolutionized the treatment of chronic lymphocytic leukemia (CLL). However, these agents are not curative, and resistance is already emerging in a proportion of patients. IL4, expressed in CLL lymph nodes, can augment BCR signaling and reduce the effectiveness of BCR kinase inhibitors. Therefore, simultaneous targeting of the IL4- and BCR signaling pathways by cerdulatinib, a novel dual Syk/JAK inhibitor currently in clinical trials (NCT01994382), may improve treatment responses in patients. Experimental Design: PBMCs from patients with CLL were treated in vitro with cerdulatinib alone or in combination with venetoclax. Cell death, chemokine, and cell signaling assay were performed and analyzed by flow cytometry, immunoblotting, q-PCR, and ELISA as indicated. Results: At concentrations achievable in patients, cerdulatinib inhibited BCR- and IL4-induced downstream signaling in CLL cells using multiple readouts and prevented anti-IgM- and nurse-like cell (NLC)-mediated CCL3/CCL4 production. Cerdulatinib induced apoptosis of CLL cells, in a time- and concentration-dependent manner, and particularly in IGHV-unmutated samples with greater BCR signaling capacity and response to IL4, or samples expressing higher levels of sIgM, CD49d
+ , or ZAP70+ Cerdulatinib overcame anti-IgM, IL4/CD40L, or NLC-mediated protection by preventing upregulation of MCL-1 and BCL-XL ; however, BCL-2 expression was unaffected. Furthermore, in samples treated with IL4/CD40L, cerdulatinib synergized with venetoclax in vitro to induce greater apoptosis than either drug alone. Conclusions: Cerdulatinib is a promising therapeutic for the treatment of CLL either alone or in combination with venetoclax, with the potential to target critical survival pathways in this currently incurable disease. Clin Cancer Res; 23(9); 2313-24. ©2016 AACR ., (©2016 American Association for Cancer Research.)- Published
- 2017
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30. Non-coding NOTCH1 mutations in chronic lymphocytic leukemia; their clinical impact in the UK CLL4 trial.
- Author
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Larrayoz M, Rose-Zerilli MJ, Kadalayil L, Parker H, Blakemore S, Forster J, Davis Z, Steele AJ, Collins A, Else M, Catovsky D, Oscier DG, and Strefford JC
- Subjects
- Humans, Leukemia, Lymphocytic, Chronic, B-Cell mortality, Prognosis, Survival Analysis, Leukemia, Lymphocytic, Chronic, B-Cell genetics, Mutation, Receptor, Notch1 genetics
- Abstract
Competing Interests: The authors declare no conflict of interest.
- Published
- 2017
- Full Text
- View/download PDF
31. Releasing the brakes on BTK-targeting miRNA.
- Author
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Blunt MD and Steele AJ
- Subjects
- Humans, Signal Transduction, MicroRNAs, Protein-Tyrosine Kinases genetics
- Published
- 2016
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32. PEITC-mediated inhibition of mRNA translation is associated with both inhibition of mTORC1 and increased eIF2α phosphorylation in established cell lines and primary human leukemia cells.
- Author
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Yeomans A, Lemm E, Wilmore S, Cavell BE, Valle-Argos B, Krysov S, Hidalgo MS, Leonard E, Willis AE, Forconi F, Stevenson FK, Steele AJ, Coldwell MJ, and Packham G
- Subjects
- Antibodies, Anti-Idiotypic pharmacology, Cell Line, Tumor, Cell Survival drug effects, Dose-Response Relationship, Drug, Gene Expression Regulation, Leukemic drug effects, Genes, myc, Humans, Leukemia, Lymphocytic, Chronic, B-Cell genetics, Leukemia, Lymphocytic, Chronic, B-Cell metabolism, MCF-7 Cells, Phosphorylation drug effects, RNA, Messenger genetics, Receptors, Antigen, B-Cell metabolism, Stress, Physiological, Transcription, Genetic drug effects, Eukaryotic Initiation Factor-2 metabolism, Isothiocyanates pharmacology, Leukemia genetics, Leukemia metabolism, Mechanistic Target of Rapamycin Complex 1 metabolism, Protein Biosynthesis drug effects
- Abstract
Increased mRNA translation drives carcinogenesis and is an attractive target for the development of new anti-cancer drugs. In this work, we investigated effects of phenethylisothiocyanate (PEITC), a phytochemical with chemopreventive and anti-cancer activity, on mRNA translation. PEITC rapidly inhibited global mRNA translation in human breast cancer-derived MCF7 cells and mouse embryonic fibroblasts (MEFs). In addition to the known inhibitory effects of PEITC on mTORC1 activity, we demonstrate that PEITC increased eIF2α phosphorylation. PEITC also increased formation of stress granules which are typically associated with eIF2α phosphorylation and accumulation of translationally stalled mRNAs. Analysis of genetically modified MEFs demonstrated that optimal inhibition of global mRNA translation by PEITC was dependent on eIF2α phosphorylation, but not mTORC1 inhibition. We extended this study into primary leukemic B cells derived from patients with chronic lymphocytic leukaemia (CLL). CLL cells were stimulated in vitro with anti-IgM to mimic binding of antigen, a major driver of this leukemia. In CLL cells, PEITC increased eIF2α phosphorylation, inhibited anti-IgM-induced mTORC1 activation and decreased both basal and anti-IgM-induced global mRNA translation. PEITC also inhibited transcription and translation of MYC mRNA and accumulation of the MYC oncoprotein, in anti-IgM-stimulated cells. Moreover, treatment of CLL cells with PEITC and the BTK kinase inhibitor ibrutinib decreased anti-IgM-induced translation and induced cell death to a greater extent than either agent alone. Therefore, PEITC can inhibit both global and mRNA specific translation (including MYC) via effects on multiple regulatory pathways. Inhibition of mRNA translation may contribute to the chemopreventive and anti-cancer effects of PEITC.
- Published
- 2016
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33. Genomic disruption of the histone methyltransferase SETD2 in chronic lymphocytic leukaemia.
- Author
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Parker H, Rose-Zerilli MJ, Larrayoz M, Clifford R, Edelmann J, Blakemore S, Gibson J, Wang J, Ljungström V, Wojdacz TK, Chaplin T, Roghanian A, Davis Z, Parker A, Tausch E, Ntoufa S, Ramos S, Robbe P, Alsolami R, Steele AJ, Packham G, Rodríguez-Vicente AE, Brown L, McNicholl F, Forconi F, Pettitt A, Hillmen P, Dyer M, Cragg MS, Chelala C, Oakes CC, Rosenquist R, Stamatopoulos K, Stilgenbauer S, Knight S, Schuh A, Oscier DG, and Strefford JC
- Subjects
- Ataxia Telangiectasia Mutated Proteins genetics, Disease-Free Survival, Female, Genes, Tumor Suppressor, Histone Methyltransferases, Humans, Leukemia, Lymphocytic, Chronic, B-Cell enzymology, Leukemia, Lymphocytic, Chronic, B-Cell mortality, Male, Prognosis, Survival Rate, Tumor Suppressor Protein p53 genetics, Genomics, Histone-Lysine N-Methyltransferase genetics, Leukemia, Lymphocytic, Chronic, B-Cell genetics, Mutation
- Abstract
Histone methyltransferases (HMTs) are important epigenetic regulators of gene transcription and are disrupted at the genomic level in a spectrum of human tumours including haematological malignancies. Using high-resolution single nucleotide polymorphism (SNP) arrays, we identified recurrent deletions of the SETD2 locus in 3% (8/261) of chronic lymphocytic leukaemia (CLL) patients. Further validation in two independent cohorts showed that SETD2 deletions were associated with loss of TP53, genomic complexity and chromothripsis. With next-generation sequencing we detected mutations of SETD2 in an additional 3.8% of patients (23/602). In most cases, SETD2 deletions or mutations were often observed as a clonal event and always as a mono-allelic lesion, leading to reduced mRNA expression in SETD2-disrupted cases. Patients with SETD2 abnormalities and wild-type TP53 and ATM from five clinical trials employing chemotherapy or chemo-immunotherapy had reduced progression-free and overall survival compared with cases wild type for all three genes. Consistent with its postulated role as a tumour suppressor, our data highlight SETD2 aberration as a recurrent, early loss-of-function event in CLL pathobiology linked to aggressive disease., Competing Interests: The authors state that that there are no conflicts of interests.
- Published
- 2016
- Full Text
- View/download PDF
34. Bimetallic MOFs (H 3 O) x [Cu(MF 6 )(pyrazine) 2 ]·(4 - x)H 2 O (M = V 4+ , x = 0; M = Ga 3+ , x = 1): co-existence of ordered and disordered quantum spins in the V 4+ system.
- Author
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Manson JL, Schlueter JA, Garrett KE, Goddard PA, Lancaster T, Möller JS, Blundell SJ, Steele AJ, Franke I, Pratt FL, Singleton J, Bendix J, Lapidus SH, Uhlarz M, Ayala-Valenzuela O, McDonald RD, Gurak M, and Baines C
- Abstract
The title compounds are bimetallic MOFs containing [Cu(pyz)
2 ]2+ square lattices linked by MF6 n- octahedra. In each, only the Cu2+ spins exhibit long-range magnetic order below 3.5 K (M = V4+ ) and 2.6 K (M = Ga3+ ). The V4+ spins remain disordered down to 0.5 K.- Published
- 2016
- Full Text
- View/download PDF
35. Surface IgM expression and function are associated with clinical behavior, genetic abnormalities, and DNA methylation in CLL.
- Author
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D'Avola A, Drennan S, Tracy I, Henderson I, Chiecchio L, Larrayoz M, Rose-Zerilli M, Strefford J, Plass C, Johnson PW, Steele AJ, Packham G, Stevenson FK, Oakes CC, and Forconi F
- Subjects
- Calcium metabolism, Disease Progression, Humans, Immunoglobulin Heavy Chains genetics, Immunoglobulin M analysis, Immunoglobulin M metabolism, Immunoglobulin Variable Region genetics, Leukemia, Lymphocytic, Chronic, B-Cell metabolism, Leukemia, Lymphocytic, Chronic, B-Cell pathology, Mutation, Receptor, Notch1 genetics, DNA Methylation, Gene Expression Regulation, Leukemic, Immunoglobulin M genetics, Leukemia, Lymphocytic, Chronic, B-Cell genetics
- Abstract
Chronic lymphocytic leukemia (CLL) with unmutated (U-CLL) or mutated (M-CLL) immunoglobulin gene heavy-chain variable region (IGHV) displays different states of anergy, indicated by reduced surface immunoglobulin M (sIgM) levels and signaling, consequent to chronic (super)antigen exposure. The subsets also differ in the incidence of high-risk genetic aberrations and in DNA methylation profile, preserved from the maturational status of the original cell. We focused on sIgM expression and function, measured as intracellular Ca(2+) mobilization following stimulation, and probed correlations with clinical outcome. The relationship with genetic features and maturation status defined by DNA methylation of an 18-gene panel signature was then investigated. sIgM levels/signaling were higher and less variable in U-CLL than in M-CLL and correlated with disease progression between and within U-CLL and M-CLL. In U-CLL, increased levels/signaling associated with +12, del(17p) or NOTCH1 mutations. In M-CLL, there were fewer genetic lesions, although the methylation maturation status, generally higher than in U-CLL, varied and was increased in cases with lower sIgM levels/signaling. These features revealed heterogeneity in M-CLL and U-CLL with clear clinical correlations. Multivariate analyses with phenotype, genetic lesions, or DNA methylation maturation status identified high sIgM levels as a new potential independent factor for disease progression. Multiple influences on sIgM include the cell of origin, the clonal history of antigen encounter in vivo, and genetic damage. This simple marker compiles these different factors into an indicator worthy of further investigations for prediction of clinical behavior, particularly within the heterogeneous M-CLL subset., (© 2016 by The American Society of Hematology.)
- Published
- 2016
- Full Text
- View/download PDF
36. To BH3 profile or not to BH3 profile.
- Author
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Blunt MD and Steele AJ
- Subjects
- Apoptosis, BH3 Interacting Domain Death Agonist Protein, Proto-Oncogene Proteins c-bcl-2
- Published
- 2016
- Full Text
- View/download PDF
37. IL-4 enhances expression and function of surface IgM in CLL cells.
- Author
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Aguilar-Hernandez MM, Blunt MD, Dobson R, Yeomans A, Thirdborough S, Larrayoz M, Smith LD, Linley A, Strefford JC, Davies A, Johnson PM, Savelyeva N, Cragg MS, Forconi F, Packham G, Stevenson FK, and Steele AJ
- Subjects
- Cell Transformation, Neoplastic drug effects, Cell Transformation, Neoplastic genetics, Cells, Cultured, Drug Interactions, Gene Expression Regulation, Leukemic drug effects, Humans, Janus Kinase 3 metabolism, Leukemia, Lymphocytic, Chronic, B-Cell immunology, Neutrophils drug effects, Neutrophils metabolism, Protein Kinase Inhibitors pharmacology, Protein-Tyrosine Kinases antagonists & inhibitors, STAT6 Transcription Factor metabolism, Signal Transduction drug effects, Up-Regulation drug effects, Cell Membrane metabolism, Immunoglobulin M genetics, Immunoglobulin M metabolism, Interleukin-4 pharmacology, Leukemia, Lymphocytic, Chronic, B-Cell genetics, Leukemia, Lymphocytic, Chronic, B-Cell metabolism
- Abstract
Kinase inhibitors targeting the B-cell receptor (BCR) are now prominent in the treatment of chronic lymphocytic leukemia (CLL). We have focused here on interleukin 4 (IL-4), a cytokine that protects normal and malignant B cells from apoptosis and increases surface immunoglobulin M (sIgM) expression on murine splenic B cells. First, we have demonstrated that IL-4 treatment increased sIgM expression in vitro on peripheral blood B cells obtained from healthy individuals. In CLL, IL-4 target genes are overexpressed in cells purified from the lymph nodes of patients compared with cells derived from matched blood and bone marrow samples. As for normal B cells, IL-4 increased sIgM expression on CLL cells in vitro, especially in samples expressing unmutated V-genes. IL-4-induced sIgM expression was associated with increased receptor signalling activity, measured by anti-IgM-induced calcium mobilization, and with increased expression of CD79B messenger RNA and protein, and the "mature" glycoform of sIgM. Importantly, the ability of the BCR-associated kinase inhibitors idelalisib and ibrutinib, approved for treatment of CLL and other B-cell malignancies, to inhibit anti-IgM-induced signalling was reduced following IL-4 pretreatment in samples from the majority of patients. In contrast to stimulatory effects on sIgM, IL-4 decreased CXCR4 and CXCR5 expression; therefore, CLL cells, particularly within the progressive unmutated V-gene subset, may harness the ability of IL-4 to promote BCR signalling and B-cell retention within lymph nodes. Effects of IL-4 were mediated via JAK3/STAT6 and we propose a potential role for JAK inhibitors in combination with BCR kinase inhibitors for the treatment of CLL., (© 2016 by The American Society of Hematology.)
- Published
- 2016
- Full Text
- View/download PDF
38. Longitudinal copy number, whole exome and targeted deep sequencing of 'good risk' IGHV-mutated CLL patients with progressive disease.
- Author
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Rose-Zerilli MJ, Gibson J, Wang J, Tapper W, Davis Z, Parker H, Larrayoz M, McCarthy H, Walewska R, Forster J, Gardiner A, Steele AJ, Chelala C, Ennis S, Collins A, Oakes CC, Oscier DG, and Strefford JC
- Subjects
- Adolescent, Adult, Aged, Clone Cells, Cytogenetic Analysis, Disease Progression, Genetic Heterogeneity, High-Throughput Nucleotide Sequencing, Humans, Longitudinal Studies, Middle Aged, Risk, Young Adult, Exome genetics, Gene Dosage, Immunoglobulin Heavy Chains genetics, Leukemia, Lymphocytic, Chronic, B-Cell genetics, Mutation
- Abstract
The biological features of IGHV-M chronic lymphocytic leukemia responsible for disease progression are still poorly understood. We undertook a longitudinal study close to diagnosis, pre-treatment and post relapse in 13 patients presenting with cMBL or Stage A disease and good-risk biomarkers (IGHV-M genes, no del(17p) or del(11q) and low CD38 expression) who nevertheless developed progressive disease, of whom 10 have required therapy. Using cytogenetics, fluorescence in situ hybridisation, genome-wide DNA methylation and copy number analysis together with whole exome, targeted deep- and Sanger sequencing at diagnosis, we identified mutations in established chronic lymphocytic leukemia driver genes in nine patients (69%), non-coding mutations (PAX5 enhancer region) in three patients and genomic complexity in two patients. Branching evolutionary trajectories predominated (n=9/13), revealing intra-tumoural epi- and genetic heterogeneity and sub-clonal competition before therapy. Of the patients subsequently requiring treatment, two had sub-clonal TP53 mutations that would not be detected by standard methodologies, three qualified for the very-low-risk category defined by integrated mutational and cytogenetic analysis and yet had established or putative driver mutations and one patient developed progressive, therapy-refractory disease associated with the emergence of an IGHV-U clone. These data suggest that extended genomic and immunogenetic screening may have clinical utility in patients with apparent good-risk disease.
- Published
- 2016
- Full Text
- View/download PDF
39. The SF3B1 inhibitor spliceostatin A (SSA) elicits apoptosis in chronic lymphocytic leukaemia cells through downregulation of Mcl-1.
- Author
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Larrayoz M, Blakemore SJ, Dobson RC, Blunt MD, Rose-Zerilli MJ, Walewska R, Duncombe A, Oscier D, Koide K, Forconi F, Packham G, Yoshida M, Cragg MS, Strefford JC, and Steele AJ
- Subjects
- Cell Line, Tumor, Dose-Response Relationship, Drug, Down-Regulation, Humans, Interleukin-4 pharmacology, Leukemia, Lymphocytic, Chronic, B-Cell pathology, Mutation, Phosphoproteins genetics, RNA Splicing, RNA Splicing Factors, Ribonucleoprotein, U2 Small Nuclear genetics, Tumor Microenvironment, bcl-X Protein antagonists & inhibitors, Apoptosis drug effects, Leukemia, Lymphocytic, Chronic, B-Cell drug therapy, Myeloid Cell Leukemia Sequence 1 Protein genetics, Phosphoproteins antagonists & inhibitors, Pyrans pharmacology, Ribonucleoprotein, U2 Small Nuclear antagonists & inhibitors, Spiro Compounds pharmacology
- Abstract
The pro-survival Bcl-2 family member Mcl-1 is expressed in chronic lymphocytic leukaemia (CLL), with high expression correlated with progressive disease. The spliceosome inhibitor spliceostatin A (SSA) is known to regulate Mcl-1 and so here we assessed the ability of SSA to elicit apoptosis in CLL. SSA induced apoptosis of CLL cells at low nanomolar concentrations in a dose- and time-dependent manner, but independently of SF3B1 mutational status, IGHV status and CD38 or ZAP70 expression. However, normal B and T cells were less sensitive than CLL cells (P=0.006 and P<0.001, respectively). SSA altered the splicing of anti-apoptotic MCL-1(L) to MCL-1(s) in CLL cells coincident with induction of apoptosis. Overexpression studies in Ramos cells suggested that Mcl-1 was important for SSA-induced killing since its expression inversely correlated with apoptosis (P=0.001). IL4 and CD40L, present in patient lymph nodes, are known to protect tumour cells from apoptosis and significantly inhibited SSA, ABT-263 and ABT-199 induced killing following administration to CLL cells (P=0.008). However, by combining SSA with the Bcl-2/Bcl-x(L) antagonists ABT-263 or ABT-199, we were able to overcome this pro-survival effect. We conclude that SSA combined with Bcl-2/Bcl-x(L) antagonists may have therapeutic utility for CLL.
- Published
- 2016
- Full Text
- View/download PDF
40. Engagement of the B-cell receptor of chronic lymphocytic leukemia cells drives global and MYC-specific mRNA translation.
- Author
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Yeomans A, Thirdborough SM, Valle-Argos B, Linley A, Krysov S, Hidalgo MS, Leonard E, Ishfaq M, Wagner SD, Willis AE, Steele AJ, Stevenson FK, Forconi F, Coldwell MJ, and Packham G
- Subjects
- Adenine analogs & derivatives, Agammaglobulinaemia Tyrosine Kinase, Antibodies, Anti-Idiotypic immunology, B-Lymphocytes metabolism, B-Lymphocytes pathology, Cell Line, Tumor, Humans, Intracellular Signaling Peptides and Proteins antagonists & inhibitors, Leukemia, Lymphocytic, Chronic, B-Cell drug therapy, Leukemia, Lymphocytic, Chronic, B-Cell pathology, Piperidines, Protein Biosynthesis drug effects, Protein Kinase Inhibitors pharmacology, Protein-Tyrosine Kinases antagonists & inhibitors, Pyrazoles pharmacology, Pyrimidines pharmacology, Receptors, Antigen, B-Cell genetics, Syk Kinase, Tumor Cells, Cultured, Gene Expression Regulation, Leukemic, Leukemia, Lymphocytic, Chronic, B-Cell genetics, Proto-Oncogene Proteins c-myc genetics, RNA, Messenger genetics, Receptors, Antigen, B-Cell immunology
- Abstract
Antigenic stimulation via the B-cell receptor (BCR) is a major driver of the proliferation and survival of chronic lymphocytic leukemia (CLL) cells. However, the precise mechanisms by which BCR stimulation leads to accumulation of malignant cells remain incompletely understood. Here, we investigated the ability of BCR stimulation to increase messenger RNA (mRNA) translation, which can promote carcinogenesis by effects on both global mRNA translation and upregulated expression of specific oncoproteins. Re-analysis of gene expression profiles revealed striking upregulation of pathways linked to mRNA translation both in CLL cells derived from lymph nodes, the major site of antigen stimulation in vivo, and after BCR stimulation in vitro. Anti-IgM significantly increased mRNA translation in primary CLL cells, measured using bulk metabolic labeling and a novel flow cytometry assay to quantify responses at a single-cell level. These translational responses were suppressed by inhibitors of BTK (ibrutinib) and SYK (tamatinib). Anti-IgM-induced mRNA translation was associated with increased expression of translation initiation factors eIF4A and eIF4GI, and reduced expression of the eIF4A inhibitor, PDCD4. Anti-IgM also increased mRNA translation in normal blood B cells, but without clear modulatory effects on these factors. In addition, anti-IgM increased translation of mRNA-encoding MYC, a major driver of disease progression. mRNA translation is likely to be an important mediator of the growth-promoting effects of antigen stimulation acting, at least in part, via translational induction of MYC. Differences in mechanisms of translational regulation in CLL and normal B cells may provide opportunities for selective therapeutic attack., (© 2016 by The American Society of Hematology.)
- Published
- 2016
- Full Text
- View/download PDF
41. Telomere length predicts progression and overall survival in chronic lymphocytic leukemia: data from the UK LRF CLL4 trial.
- Author
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Strefford JC, Kadalayil L, Forster J, Rose-Zerilli MJ, Parker A, Lin TT, Heppel N, Norris K, Gardiner A, Davies Z, Gonzalez de Castro D, Else M, Steele AJ, Parker H, Stankovic T, Pepper C, Fegan C, Baird D, Collins A, Catovsky D, and Oscier DG
- Subjects
- Disease Progression, Genes, p53, Humans, Immunoglobulin Heavy Chains genetics, Leukemia, Lymphocytic, Chronic, B-Cell mortality, Mutation, Leukemia, Lymphocytic, Chronic, B-Cell genetics, Telomere
- Published
- 2015
- Full Text
- View/download PDF
42. Pharmacological targeting of PI3K isoforms as a therapeutic strategy in chronic lymphocytic leukaemia.
- Author
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Blunt MD and Steele AJ
- Abstract
PI3Kδ inhibitors such as idelalisib are providing improved therapeutic options for the treatment of chronic lymphocytic leukaemia (CLL). However under certain conditions, inhibition of a single PI3K isoform can be compensated by the other PI3K isoforms, therefore PI3K inhibitors which target multiple PI3K isoforms may provide greater efficacy. The development of compounds targeting multiple PI3K isoforms (α, β, δ, and γ) in CLL cells, in vitro, resulted in sustained inhibition of BCR signalling but with enhanced cytotoxicity and the potential for improve clinical responses. This review summarises the progress of PI3K inhibitor development and describes the rationale and potential for targeting multiple PI3K isoforms.
- Published
- 2015
- Full Text
- View/download PDF
43. Higher levels of reactive oxygen species are associated with anergy in chronic lymphocytic leukemia.
- Author
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Linley A, Valle-Argos B, Steele AJ, Stevenson FK, Forconi F, and Packham G
- Subjects
- Antineoplastic Agents therapeutic use, Apoptosis genetics, Apoptosis immunology, B-Lymphocytes pathology, Fluoresceins, Fluorescent Dyes, Gene Expression, Humans, Leukemia, Lymphocytic, Chronic, B-Cell drug therapy, Leukemia, Lymphocytic, Chronic, B-Cell genetics, Leukemia, Lymphocytic, Chronic, B-Cell mortality, Receptors, CXCR4 genetics, Receptors, CXCR4 immunology, Survival Analysis, Time-to-Treatment, B-Lymphocytes immunology, Clonal Anergy, Leukemia, Lymphocytic, Chronic, B-Cell immunology, Reactive Oxygen Species immunology
- Published
- 2015
- Full Text
- View/download PDF
44. The PI3K/mTOR inhibitor PF-04691502 induces apoptosis and inhibits microenvironmental signaling in CLL and the Eµ-TCL1 mouse model.
- Author
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Blunt MD, Carter MJ, Larrayoz M, Smith LD, Aguilar-Hernandez M, Cox KL, Tipton T, Reynolds M, Murphy S, Lemm E, Dias S, Duncombe A, Strefford JC, Johnson PW, Forconi F, Stevenson FK, Packham G, Cragg MS, and Steele AJ
- Subjects
- Animals, Blotting, Western, Cells, Cultured, Disease Models, Animal, Female, Humans, Leukemia, Lymphocytic, Chronic, B-Cell metabolism, Mice, Mice, Inbred C57BL, Phosphoinositide-3 Kinase Inhibitors, TOR Serine-Threonine Kinases antagonists & inhibitors, Antineoplastic Agents pharmacology, Apoptosis drug effects, Leukemia, Lymphocytic, Chronic, B-Cell pathology, Pyridones pharmacology, Pyrimidines pharmacology, Signal Transduction drug effects
- Abstract
Current treatment strategies for chronic lymphocytic leukemia (CLL) involve a combination of conventional chemotherapeutics, monoclonal antibodies, and targeted signaling inhibitors. However, CLL remains largely incurable, with drug resistance and treatment relapse a common occurrence, leading to the search for novel treatments. Mechanistic target of rapamycin (mTOR)-specific inhibitors have been previously assessed but their efficacy is limited due to a positive feedback loop via mTOR complex 2 (mTORC2), resulting in activation of prosurvival signaling. In this study, we show that the dual phosphatidylinositol 3-kinase (PI3K)/mTOR inhibitor PF-04691502 does not induce an mTORC2 positive feedback loop similar to other PI3K inhibitors but does induce substantial antitumor effects. PF-04691502 significantly reduced survival coincident with the induction of Noxa and Puma, independently of immunoglobulin heavy chain variable region mutational status, CD38, and ZAP-70 expression. PF-04691502 inhibited both anti-immunoglobulin M-induced signaling and overcame stroma-induced survival signals and migratory stimuli from CXCL12. Equivalent in vitro activity was seen in the Eμ-TCL1 murine model of CLL. In vivo, PF-04691502 treatment of tumor-bearing animals resulted in a transient lymphocytosis, followed by a clear reduction in tumor in the blood, bone marrow, spleen, and lymph nodes. These data indicate that PF-04691502 or other dual PI3K/mTOR inhibitors in development may prove efficacious for the treatment of CLL, increasing our armamentarium to successfully manage this disease., (© 2015 by The American Society of Hematology.)
- Published
- 2015
- Full Text
- View/download PDF
45. Low frequency mutations independently predict poor treatment-free survival in early stage chronic lymphocytic leukemia and monoclonal B-cell lymphocytosis.
- Author
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Winkelmann N, Rose-Zerilli M, Forster J, Parry M, Parker A, Gardiner A, Davies Z, Steele AJ, Parker H, Cross NC, Oscier DG, and Strefford JC
- Subjects
- Aged, Cohort Studies, Female, Humans, Leukemia, Lymphocytic, Chronic, B-Cell mortality, Lymphocytosis mortality, Male, Predictive Value of Tests, Survival Rate trends, Treatment Outcome, B-Lymphocytes pathology, Leukemia, Lymphocytic, Chronic, B-Cell diagnosis, Leukemia, Lymphocytic, Chronic, B-Cell genetics, Lymphocytosis diagnosis, Lymphocytosis genetics, Mutation genetics
- Published
- 2015
- Full Text
- View/download PDF
46. A gene-expression-based neural code for food abundance that modulates lifespan.
- Author
-
Entchev EV, Patel DS, Zhan M, Steele AJ, Lu H, and Ch'ng Q
- Subjects
- Animals, Caenorhabditis elegans metabolism, Caenorhabditis elegans Proteins metabolism, Eating physiology, Gene Expression Regulation, Mutation, Nervous System cytology, Neurons cytology, Serotonin metabolism, Signal Transduction, Transforming Growth Factor beta metabolism, Tryptophan Hydroxylase metabolism, Caenorhabditis elegans genetics, Caenorhabditis elegans Proteins genetics, Longevity genetics, Nervous System metabolism, Neurons metabolism, Transforming Growth Factor beta genetics, Tryptophan Hydroxylase genetics
- Abstract
How the nervous system internally represents environmental food availability is poorly understood. Here, we show that quantitative information about food abundance is encoded by combinatorial neuron-specific gene-expression of conserved TGFβ and serotonin pathway components in Caenorhabditis elegans. Crosstalk and auto-regulation between these pathways alters the shape, dynamic range, and population variance of the gene-expression responses of daf-7 (TGFβ) and tph-1 (tryptophan hydroxylase) to food availability. These intricate regulatory features provide distinct mechanisms for TGFβ and serotonin signaling to tune the accuracy of this multi-neuron code: daf-7 primarily regulates gene-expression variability, while tph-1 primarily regulates the dynamic range of gene-expression responses. This code is functional because daf-7 and tph-1 mutations bidirectionally attenuate food level-dependent changes in lifespan. Our results reveal a neural code for food abundance and demonstrate that gene expression serves as an additional layer of information processing in the nervous system to control long-term physiology.
- Published
- 2015
- Full Text
- View/download PDF
47. Rewiring of sIgM-Mediated Intracellular Signaling through the CD180 Toll-like Receptor.
- Author
-
Porakishvili N, Vispute K, Steele AJ, Rajakaruna N, Kulikova N, Tsertsvadze T, Nathwani A, Damle RN, Clark EA, Rai KR, Chiorazzi N, and Lydyard PM
- Abstract
Chronic lymphocytic leukemia (CLL) development and progression are thought to be driven by unknown antigens/autoantigens through the B cell receptor (BCR) and environmental signals for survival and expansion including toll-like receptor (TLR) ligands. CD180/RP105, a membrane-associated orphan receptor of the TLR family, induces normal B cell activation and proliferation and is expressed by approximately 60% of CLL samples. Half of these respond to ligation with anti-CD180 antibody by increased activation/phosphorylation of protein kinases associated with BCR signaling. Hence CLL cells expressing both CD180 and the BCR could receive signals via both receptors. Here we investigated cross-talk between BCR and CD180-mediated signaling on CLL cell survival and apoptosis. Our data indicate that ligation of CD180 on responsive CLL cells leads to activation of either prosurvival Bruton tyrosine kinase (BTK)/phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/AKT-mediated, or proapoptotic p38 mitogen-activated protein kinase (p38MAPK)-mediated signaling pathways, while selective immunoglobulin M (sIgM) ligation predominantly engages the BTK/PI3K/AKT pathway. Furthermore, pretreatment of CLL cells with anti-CD180 redirects IgM-mediated signaling from the prosurvival BTK/PI3K/AKT toward the proapoptotic p38MAPK pathway. Thus preengaging CD180 could prevent further prosurvival signaling mediated via the BCR and, instead, induce CLL cell apoptosis, opening the door to therapeutic profiling and new strategies for the treatment of a substantial cohort of CLL patients.
- Published
- 2015
- Full Text
- View/download PDF
48. PI3K in CLL: are 2 isoforms better than 1?
- Author
-
Steele AJ
- Subjects
- Female, Humans, Male, Antineoplastic Agents pharmacology, Class I Phosphatidylinositol 3-Kinases antagonists & inhibitors, Enzyme Inhibitors pharmacology, Isoquinolines pharmacology, Leukemia, Lymphocytic, Chronic, B-Cell drug therapy, Neoplasm Proteins antagonists & inhibitors, Purines pharmacology, Signal Transduction drug effects
- Published
- 2014
- Full Text
- View/download PDF
49. Stimulation of surface IgM of chronic lymphocytic leukemia cells induces an unfolded protein response dependent on BTK and SYK.
- Author
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Krysov S, Steele AJ, Coelho V, Linley A, Sanchez Hidalgo M, Carter M, Potter KN, Kennedy B, Duncombe AS, Ashton-Key M, Forconi F, Stevenson FK, and Packham G
- Subjects
- Agammaglobulinaemia Tyrosine Kinase, B-Lymphocytes pathology, Humans, Leukemia, Lymphocytic, Chronic, B-Cell pathology, Signal Transduction, Syk Kinase, B-Lymphocytes immunology, Immunoglobulin M immunology, Intracellular Signaling Peptides and Proteins immunology, Leukemia, Lymphocytic, Chronic, B-Cell immunology, Protein-Tyrosine Kinases immunology, Receptors, Antigen, B-Cell immunology, Unfolded Protein Response
- Abstract
B-cell receptor (BCR) signaling plays a key role in the behavior of chronic lymphocytic leukemia (CLL). However, cellular consequences of signaling are incompletely defined. Here we explored possible links between BCR signaling and the unfolded protein response (UPR), a stress response pathway that can promote survival of normal and malignant cells. Compared with normal B cells, circulating CLL cells expressed increased, but variable, levels of UPR components. Higher expression of CHOP and XBP1 RNAs was associated with more aggressive disease. UPR activation appeared due to prior tissue-based antigenic stimulation because elevated expression of UPR components was detected within lymph node proliferation centers. Basal UPR activation also correlated closely with surface immunoglobulin M (sIgM) signaling capacity in vitro in both IGHV unmutated CLL and within mutated CLL. sIgM signaling increased UPR activation in vitro with responders showing increased expression of CHOP and XBP1 RNAs, and PERK and BIP proteins, but not XBP1 splicing. Inhibitors of BCR-associated kinases effectively prevented sIgM-induced UPR activation. Overall, this study demonstrates that sIgM signaling results in activation of some components the UPR in CLL cells. Modulation of the UPR may contribute to variable clinical behavior, and its inhibition may contribute to clinical responses to BCR-associated kinase inhibitors., (© 2014 by The American Society of Hematology.)
- Published
- 2014
- Full Text
- View/download PDF
50. Tumour cells expressing single VEGF isoforms display distinct growth, survival and migration characteristics.
- Author
-
Kanthou C, Dachs GU, Lefley DV, Steele AJ, Coralli-Foxon C, Harris S, Greco O, Dos Santos SA, Reyes-Aldasoro CC, English WR, and Tozer GM
- Subjects
- Animals, Apoptosis, Carcinogenesis genetics, Cell Adhesion, Cell Line, Tumor, Cell Survival genetics, Fibrosarcoma pathology, Gene Expression Regulation, Neoplastic, Mice, Neoplasm Metastasis genetics, Protein Isoforms chemistry, Protein Isoforms metabolism, Receptors, Vascular Endothelial Growth Factor metabolism, Vascular Endothelial Growth Factor A chemistry, Cell Movement genetics, Cell Proliferation genetics, Fibrosarcoma metabolism, Vascular Endothelial Growth Factor A metabolism
- Abstract
Vascular endothelial growth factor-A (VEGF) is produced by most cancer cells as multiple isoforms, which display distinct biological activities. VEGF plays an undisputed role in tumour growth, vascularisation and metastasis; nevertheless the functions of individual isoforms in these processes remain poorly understood. We investigated the effects of three main murine isoforms (VEGF188, 164 and 120) on tumour cell behaviour, using a panel of fibrosarcoma cells we developed that express them individually under endogenous promoter control. Fibrosarcomas expressing only VEGF188 (fs188) or wild type controls (fswt) were typically mesenchymal, formed ruffles and displayed strong matrix-binding activity. VEGF164- and VEGF120-producing cells (fs164 and fs120 respectively) were less typically mesenchymal, lacked ruffles but formed abundant cell-cell contacts. On 3D collagen, fs188 cells remained mesenchymal while fs164 and fs120 cells adopted rounded/amoeboid and a mix of rounded and elongated morphologies respectively. Consistent with their mesenchymal characteristics, fs188 cells migrated significantly faster than fs164 or fs120 cells on 2D surfaces while contractility inhibitors accelerated fs164 and fs120 cell migration. VEGF164/VEGF120 expression correlated with faster proliferation rates and lower levels of spontaneous apoptosis than VEGF188 expression. Nevertheless, VEGF188 was associated with constitutively active/phosphorylated AKT, ERK1/2 and Stat3 proteins. Differences in proliferation rates and apoptosis could be explained by defective signalling downstream of pAKT to FOXO and GSK3 in fs188 and fswt cells, which also correlated with p27/p21 cyclin-dependent kinase inhibitor over-expression. All cells expressed tyrosine kinase VEGF receptors, but these were not active/activatable suggesting that inherent differences between the cell lines are governed by endogenous VEGF isoform expression through complex interactions that are independent of tyrosine kinase receptor activation. VEGF isoforms are emerging as potential biomarkers for anti-VEGF therapies. Our results reveal novel roles of individual isoforms associated with cancer growth and metastasis and highlight the importance of understanding their diverse actions.
- Published
- 2014
- Full Text
- View/download PDF
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