ABSTRACT
Mammalian switch/sucrose non-fermentable (mSWI/SNF) complexes are multi-component machines that remodel chromatin architecture. Dissection of the subunit- and domain-specific contributions to complex activities is needed to advance mechanistic understanding. Here, we examine the molecular, structural, and genome-wide regulatory consequences of recurrent, single-residue mutations in the putative coiled-coil C-terminal domain (CTD) of the SMARCB1 (BAF47) subunit, which cause the intellectual disability disorder Coffin-Siris syndrome (CSS), and are recurrently found in cancers. We find that the SMARCB1 CTD contains a basic α helix that binds directly to the nucleosome acidic patch and that all CSS-associated mutations disrupt this binding. Furthermore, these mutations abrogate mSWI/SNF-mediated nucleosome remodeling activity and enhancer DNA accessibility without changes in genome-wide complex localization. Finally, heterozygous CSS-associated SMARCB1 mutations result in dominant gene regulatory and morphologic changes during iPSC-neuronal differentiation. These studies unmask an evolutionarily conserved structural role for the SMARCB1 CTD that is perturbed in human disease.
Subject(s)
Chromatin Assembly and Disassembly/genetics , Chromosomal Proteins, Non-Histone/metabolism , Mutation/genetics , Nucleosomes/metabolism , SMARCB1 Protein/genetics , Transcription Factors/metabolism , Amino Acid Sequence , Enhancer Elements, Genetic/genetics , Female , Genome, Human , HEK293 Cells , HeLa Cells , Heterozygote , Humans , Male , Models, Molecular , Mutant Proteins/chemistry , Mutant Proteins/metabolism , Protein Binding , Protein Domains , SMARCB1 Protein/chemistry , SMARCB1 Protein/metabolismABSTRACT
An Amendment to this paper has been published and can be accessed via a link at the top of the paper.
ABSTRACT
Chemotherapy-induced peripheral neuropathy (CIPN) is a disabling side effect of cancer chemotherapy that can often limit treatment options for cancer patients or have life-long neurodegenerative consequences that reduce the patient's quality of life. CIPN is caused by the detrimental actions of various chemotherapeutic agents on peripheral axons. Currently, there are no approved preventative measures or treatment options for CIPN, highlighting the need for the discovery of novel therapeutics and improving our understanding of disease mechanisms. In this study, we utilized human-induced pluripotent stem cell (hiPSC)-derived motor neurons as a platform to mimic axonal damage after treatment with vincristine, a chemotherapeutic used for the treatment of breast cancers, osteosarcomas, and leukemia. We screened a total of 1902 small molecules for neuroprotective properties in rescuing vincristine-induced axon growth deficits. From our primary screen, we identified 38 hit compounds that were subjected to secondary dose response screens. Six compounds showed favorable pharmacological profiles - AZD7762, A-674563, Blebbistatin, Glesatinib, KW-2449, and Pelitinib, all novel neuroprotectants against vincristine toxicity to neurons. In addition, four of these six compounds also showed efficacy against vincristine-induced growth arrest in human iPSC-derived sensory neurons. In this study, we utilized high-throughput screening of a large library of compounds in a therapeutically relevant assay. We identified several novel compounds that are efficacious in protecting different neuronal subtypes from the toxicity induced by a common chemotherapeutic agent, vincristine which could have therapeutic potential in the clinic.
Subject(s)
Induced Pluripotent Stem Cells , Neuroprotective Agents , Vincristine , Vincristine/pharmacology , Humans , Induced Pluripotent Stem Cells/drug effects , Induced Pluripotent Stem Cells/metabolism , Induced Pluripotent Stem Cells/cytology , Neuroprotective Agents/pharmacology , Motor Neurons/drug effects , Motor Neurons/pathology , Motor Neurons/metabolism , Axons/drug effects , Axons/metabolism , Axons/pathology , Neurons/drug effects , Neurons/metabolism , Neurons/pathology , Cells, Cultured , Peripheral Nervous System Diseases/chemically induced , Peripheral Nervous System Diseases/pathology , Peripheral Nervous System Diseases/drug therapyABSTRACT
Genetic regulators and environmental stimuli modulate T cell activation in autoimmunity and cancer. The enzyme co-factor tetrahydrobiopterin (BH4) is involved in the production of monoamine neurotransmitters, the generation of nitric oxide, and pain1,2. Here we uncover a link between these processes, identifying a fundamental role for BH4 in T cell biology. We find that genetic inactivation of GTP cyclohydrolase 1 (GCH1, the rate-limiting enzyme in the synthesis of BH4) and inhibition of sepiapterin reductase (the terminal enzyme in the synthetic pathway for BH4) severely impair the proliferation of mature mouse and human T cells. BH4 production in activated T cells is linked to alterations in iron metabolism and mitochondrial bioenergetics. In vivo blockade of BH4 synthesis abrogates T-cell-mediated autoimmunity and allergic inflammation, and enhancing BH4 levels through GCH1 overexpression augments responses by CD4- and CD8-expressing T cells, increasing their antitumour activity in vivo. Administration of BH4 to mice markedly reduces tumour growth and expands the population of intratumoral effector T cells. Kynurenine-a tryptophan metabolite that blocks antitumour immunity-inhibits T cell proliferation in a manner that can be rescued by BH4. Finally, we report the development of a potent SPR antagonist for possible clinical use. Our data uncover GCH1, SPR and their downstream metabolite BH4 as critical regulators of T cell biology that can be readily manipulated to either block autoimmunity or enhance anticancer immunity.
Subject(s)
Autoimmune Diseases/immunology , Biopterins/analogs & derivatives , Neoplasms/immunology , T-Lymphocytes/cytology , T-Lymphocytes/immunology , Administration, Oral , Alcohol Oxidoreductases/antagonists & inhibitors , Alcohol Oxidoreductases/metabolism , Animals , Autoimmune Diseases/drug therapy , Autoimmune Diseases/pathology , Biopterins/biosynthesis , Biopterins/metabolism , Biopterins/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Coenzymes/metabolism , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Female , GTP Cyclohydrolase/genetics , GTP Cyclohydrolase/metabolism , Humans , Hypersensitivity/immunology , Iron/metabolism , Kynurenine/metabolism , Kynurenine/pharmacology , Male , Mice , Mice, Inbred C57BL , Mitochondria/metabolism , Neoplasms/drug therapy , Neoplasms/pathology , T-Lymphocytes/drug effects , T-Lymphocytes/metabolismABSTRACT
BACKGROUND: Adjuvant chemotherapy for patients with early breast cancer improves outcomes but its toxicity affects patients' quality of life (QOL). The UK TACT2 trial investigated whether accelerated epirubicin improves time to recurrence and if oral capecitabine is non-inferior to cyclophosphamide, methotrexate, and fluorouracil (CMF) for efficacy with less toxicity. Results showed no benefit for accelerated epirubicin and capecitabine was non-inferior. As part of the QOL substudy, we aimed to assess the effect of chemotherapies on psychological distress, physical symptoms, and functional domains. METHODS: TACT2 was a multicentre, phase 3, open-label, parallel-group, randomised, controlled trial done in 129 UK centres. Participants were aged 18 years or older with histologically confirmed node-positive or high-risk node-negative invasive primary breast cancer, who had undergone complete excision, and due to receive adjuvant chemotherapy. Patients were randomly assigned (1:1:1:1) to four cycles of 100 mg/m2 epirubicin either every 3 weeks (standard epirubicin) or every 2 weeks with 6 mg pegfilgrastim on day 2 of each cycle (accelerated epirubicin), followed by four 4-week cycles of either CMF (600 mg/m2 cyclophosphamide intravenously on days 1 and 8 or 100 mg/m2 orally on days 1-14; 40 mg/m2 methotrexate intravenously on days 1 and 8; and 600 mg/m2 fluorouracil intravenously on days 1 and 8 of each cycle) or four 3-week cycles of 2500 mg/m2 capecitabine (1250 mg/m2 given twice daily on days 1-14 of each cycle). The randomisation schedule was computer generated in random permuted blocks, stratified by centre, number of nodes involved (none vs 1-3 vs ≥4), age (≤50 years vs >50 years), and planned endocrine treatment (yes vs no). QOL was one of the secondary outcomes and is reported here. All patients from a subset of 44 centres were invited to complete QOL questionnaires (Hospital Anxiety and Depression Scale [HADS] and European Organisation for Research and Treatment of Cancer [EORTC] Quality of Life Questionnaire 30-item core module [QLQ-C30] and Quality of Life Questionnaire breast module [QLQ-BR23]) at baseline, end of standard or accelerated epirubicin, end of CMF or capecitabine, and at 12 and 24 months after randomisation. The QOL substudy prespecified two coprimary QOL outcomes assessed in the intention-to-treat population: overall QOL (reported elsewhere) and HADS total score. Prespecified secondary QOL outcomes were EORTC QLQ-C30 subscales of physical function, role function, and fatigue and EORTC QLQ-BR23 subscales of sexual function and systemic therapy side-effects. This trial is registered with ISRCTN, ISRCTN68068041, and ClinicalTrials.gov, NCT00301925. FINDINGS: From Dec 16, 2005, to Dec 5, 2008, 4391 patients (20 [0·5%] of whom were male) were enrolled in TACT2; 1281 (85·8%) of 1493 eligible patients were included in the QOL substudy. Eight (0·6%) participants in the QOL substudy were male and 1273 (99·4%) were female. Median follow-up was 85·6 months (IQR 80·6-95·9). Analysis was performed on the complete QOL dataset (as of Sept 15, 2011) when all participants had passed the 24-month timepoint. Prerandomisation questionnaires were completed by 1172 (91·5%) patients and 1179 (92·0%) completed at least one postrandomisation questionnaire. End-of-treatment HADS depression score (p=0·0048) and HADS total change score (p=0·0093) were worse for CMF versus capecitabine. Accelerated epirubicin led to worse physical function (p=0·0065), role function (p<0·0001), fatigue (p=0·0002), and systemic side-effects (p=0·0001), but not sexual function (p=0·36), compared with standard epirubicin during treatment, but the effect did not persist. Worse physical function (p=0·0048), sexual function (p=0·0053), fatigue (p<0·0001), and systemic side-effects (p<0·0001), but not role functioning (p=0·013), were seen for CMF versus capecitabine at end of treatment; these differences persisted at 12 months and 24 months. INTERPRETATION: Accelerated epirubicin was associated with worse QOL than was standard epirubicin but only during treatment. These findings will help patients and clinicians make an informed choice about accelerated chemotherapy. CMF had worse QOL effects than did capecitabine, which were persistent for 24 months. The favourable capecitabine QOL compared with CMF supports its use as an adjuvant option after neoadjuvant chemotherapy in patients with triple-negative breast cancer. FUNDING: Cancer Research UK, Amgen, Pfizer, and Roche.
Subject(s)
Breast Neoplasms , Humans , Male , Female , Breast Neoplasms/pathology , Capecitabine , Epirubicin/adverse effects , Methotrexate/adverse effects , Quality of Life , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Fluorouracil , Cyclophosphamide , Chemotherapy, Adjuvant/methods , Fatigue/chemically induced , United KingdomABSTRACT
PURPOSE: The development of oestrogen resistance is a major challenge in managing hormone-sensitive metastatic breast cancer. Saracatinib (AZD0530), an oral Src kinase inhibitor, prevents oestrogen resistance in animal models and reduces osteoclast activity. We aimed to evaluate the efficacy of saracatinib addition to aromatase inhibitors (AI) in patients with hormone receptor-positive metastatic breast cancer. METHODS: This phase II multicentre double-blinded randomised trial allocated post-menopausal women to AI with either saracatinib or placebo (1:1 ratio). Patients were stratified into an "AI-sensitive/naïve" group who received anastrozole and "prior-AI" group who received exemestane. Primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate (ORR) and toxicity. RESULTS: 140 patients were randomised from 20 UK centres to saracatinib/AI (n = 69) or placebo/AI (n = 71). Saracatinib was not associated with an improved PFS (3.7 months v. 5.6 months placebo/AI) and did not reduce likelihood of bony progression. There was no benefit in OS or ORR. Effects were consistent in "AI-sensitive/naive" and "prior-AI" sub-groups. Saracatinib was well tolerated with dose reductions in 16% and the main side effects were gastrointestinal, hypophosphatemia and rash. CONCLUSION: Saracatinib did not improve outcomes in post-menopausal women with metastatic breast cancer. There was no observed beneficial effect on bone metastases. CRUKE/11/023, ISRCTN23804370.
Subject(s)
Breast Neoplasms , Female , Humans , Breast Neoplasms/pathology , Aromatase Inhibitors/adverse effects , Aromatase , Estrogens/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic useABSTRACT
Deficiency of the adaptor protein complex 4 (AP-4) leads to childhood-onset hereditary spastic paraplegia (AP-4-HSP): SPG47 (AP4B1), SPG50 (AP4M1), SPG51 (AP4E1) and SPG52 (AP4S1). This study aims to evaluate the impact of loss-of-function variants in AP-4 subunits on intracellular protein trafficking using patient-derived cells. We investigated 15 patient-derived fibroblast lines and generated six lines of induced pluripotent stem cell (iPSC)-derived neurons covering a wide range of AP-4 variants. All patient-derived fibroblasts showed reduced levels of the AP4E1 subunit, a surrogate for levels of the AP-4 complex. The autophagy protein ATG9A accumulated in the trans-Golgi network and was depleted from peripheral compartments. Western blot analysis demonstrated a 3-5-fold increase in ATG9A expression in patient lines. ATG9A was redistributed upon re-expression of AP4B1 arguing that mistrafficking of ATG9A is AP-4-dependent. Examining the downstream effects of ATG9A mislocalization, we found that autophagic flux was intact in patient-derived fibroblasts both under nutrient-rich conditions and when autophagy is stimulated. Mitochondrial metabolism and intracellular iron content remained unchanged. In iPSC-derived cortical neurons from patients with AP4B1-associated SPG47, AP-4 subunit levels were reduced while ATG9A accumulated in the trans-Golgi network. Levels of the autophagy marker LC3-II were reduced, suggesting a neuron-specific alteration in autophagosome turnover. Neurite outgrowth and branching were reduced in AP-4-HSP neurons pointing to a role of AP-4-mediated protein trafficking in neuronal development. Collectively, our results establish ATG9A mislocalization as a key marker of AP-4 deficiency in patient-derived cells, including the first human neuron model of AP-4-HSP, which will aid diagnostic and therapeutic studies.
Subject(s)
Adaptor Protein Complex 4/genetics , Adaptor Protein Complex 4/metabolism , Autophagy-Related Proteins/metabolism , Membrane Proteins/metabolism , Protein Transport/genetics , Spastic Paraplegia, Hereditary/metabolism , Vesicular Transport Proteins/metabolism , trans-Golgi Network/metabolism , Adaptor Protein Complex 4/deficiency , Adaptor Protein Complex beta Subunits/metabolism , Adolescent , Autophagosomes/metabolism , Autophagy/genetics , Cell Line , Child , Child, Preschool , Female , Fibroblasts/metabolism , Humans , Induced Pluripotent Stem Cells/metabolism , Iron/metabolism , Loss of Function Mutation , Male , Microtubule-Associated Proteins/metabolism , Mitochondria/metabolism , Neurogenesis/genetics , Neurons/metabolism , Spastic Paraplegia, Hereditary/genetics , trans-Golgi Network/geneticsABSTRACT
The association between breast cancer and benign thyroid disorders, in particular thyroid autoimmunity, has been debated for decades. Autoantibodies to thyroid peroxidase, the hallmark of thyroid autoimmunity, have a higher prevalence among patients with breast cancer compared with the general population. Furthermore a correlation between their positivity and a better prognosis of breast cancer was found in several independent small-scale studies, even if such observation was not confirmed in a subsequent retrospective study conducted on the largest patient cohort to date. The thyroid and mammary glands present several biological similarities, therefore the hypothesis of an immune response to shared thyroid/breast antigens could in part explain the association between thyroid autoimmunity and breast cancer. The sodium iodide symporter is expressed in both glands, however it seems unlikely to be the key common antigen, considering that autoantibodies targeting it are rare. Instead thyroid peroxidase, one of the major thyroid autoantigens, is also expressed in breast tissue and therefore represents the main antigenic link between thyroid autoimmunity and breast cancer. Furthermore lactoperoxidase, an enzyme of the same family that shares structural similarities with thyroid peroxidase, is expressed in neoplastic breast cells and is responsible for the cross-reactivity with some autoantibodies to thyroid peroxidase. Novel strategies for the diagnosis and treatment of breast cancer might take advantage of the antigenic link between thyroid and breast tissues.
Subject(s)
Autoantibodies/immunology , Autoimmunity/immunology , Breast Neoplasms/immunology , Thyroid Diseases/immunology , Thyroid Gland/immunology , Animals , Breast Neoplasms/epidemiology , Breast Neoplasms/pathology , Female , Humans , Thyroid Diseases/complicationsABSTRACT
Clinical pathways are used to guide clinicians to provide a standardised delivery of care. Because of their standardisation, the aim of clinical pathways is to reduce variation in both care process and patient outcomes. When learning clinical pathways from data through data mining, it is common practice to represent each patient pathway as a string corresponding to their movements through activities. Clustering techniques are popular methods for pathway mining, and therefore this paper focuses on distance metrics applied to string data for k-medoids clustering. The two main aims are to firstly, develop a technique that seamlessly integrates expert information with data and secondly, to develop a string distance metric for the purpose of process data. The overall goal was to allow for more meaningful clustering results to be found by adding context into the string similarity calculation. Eight common distance metrics and their applicability are discussed. These distance metrics prove to give an arbitrary distance, without consideration for context, and each produce different results. As a result, this paper describes the development of a new distance metric, the modified Needleman-Wunsch algorithm, that allows for expert interaction with the calculation by assigning groupings and rankings to activities, which provide context to the strings. This algorithm has been developed in partnership with UK's National Health Service (NHS) with the focus on a lung cancer pathway, however the handling of the data and algorithm allows for application to any disease type. This method is contained within Sim.Pro.Flow, a publicly available decision support tool.
Subject(s)
Critical Pathways , State Medicine , Algorithms , Cluster Analysis , Data Mining , HumansABSTRACT
BACKGROUND: Adjuvant chemotherapy for early breast cancer has improved outcomes but causes toxicity. The UK TACT2 trial used a 2×2 factorial design to test two hypotheses: whether use of accelerated epirubicin would improve time to tumour recurrence (TTR); and whether use of oral capecitabine instead of cyclophosphamide would be non-inferior in terms of patients' outcomes and would improve toxicity, quality of life, or both. METHODS: In this multicentre, phase 3, randomised, controlled trial, we enrolled patients aged 18 years or older from 129 UK centres who had histologically confirmed node-positive or high-risk node-negative operable breast cancer, had undergone complete excision, and were due to receive adjuvant chemotherapy. Patients were randomly assigned to receive four cycles of 100 mg/m2 epirubicin either every 3 weeks (standard epirubicin) or every 2 weeks with 6 mg pegfilgrastim on day 2 of each cycle (accelerated epirubicin), followed by four 4-week cycles of either classic cyclophosphamide, methotrexate, and fluorouracil (CMF; 600 mg/m2 cyclophosphamide intravenously on days 1 and 8 or 100 mg/m2 orally on days 1-14; 40 mg/m2 methotrexate intravenously on days 1 and 8; and 600 mg/m2 fluorouracil intravenously on days 1 and 8 of each cycle) or four 3-week cycles of 2500 mg/m2 capecitabine (1250 mg/m2 given twice daily on days 1-14 of each cycle). The randomisation schedule was computer generated in random permuted blocks, stratified by centre, number of nodes involved (none vs one to three vs four or more), age (≤50 years vs >50 years), and planned endocrine treatment (yes vs no). The primary endpoint was TTR, defined as time from randomisation to first invasive relapse or breast cancer death, with intention-to-treat analysis of standard versus accelerated epirubicin and per-protocol analysis of CMF versus capecitabine. This trial is registered with ISRCTN, number 68068041, and with ClinicalTrials.gov, number NCT00301925. FINDINGS: From Dec 16, 2005, to Dec 5, 2008, 4391 patients (4371 women and 20 men) were recruited. At a median follow-up of 85·6 months (IQR 80·6-95·9) no significant difference was seen in the proportions of patients free from TTR events between the accelerated and standard epirubicin groups (overall hazard ratio [HR] 0·94, 95% CI 0·81-1·09; stratified p=0·42). At 5 years, 85·9% (95% CI 84·3-87·3) of patients receiving standard epirubicin and 87·1% (85·6-88·4) of those receiving accelerated epirubicin were free from TTR events. 4358 patients were included in the per-protocol analysis, and no difference was seen in the proportions of patients free from TTR events between the CMF and capecitabine groups (HR 0·98, 95% CI 0·85-1.14; stratified p=0·00092 for non-inferiority). Compared with baseline, significantly more patients taking CMF than those taking capecitabine had clinically relevant worsening of quality of life at end of treatment (255 [58%] of 441 vs 235 [50%] of 475; p=0·011) and at 12 months (114 [34%] of 334 vs 89 [22%] of 401; p<0·001 at 12 months) and had worse quality of life over time (p<0·0001). Detailed toxicity and quality-of-life data were collected from 2115 (48%) of treated patients. The most common grade 3 or higher adverse events in cycles 1-4 were neutropenia (175 [16%]) and fatigue (56 [5%]) of the 1070 patients treated with standard epirubicin, and fatigue (63 [6%]) and infection (34 [3%]) of the 1045 patients treated with accelerated epirubicin. In cycles 5-8, the most common grade 3 or higher adverse events were neutropenia (321 [31%]) and fatigue (109 [11%]) in the patients treated with CMF, and hand-foot syndrome (129 [12%]) and diarrhoea (67 [6%]) in the 1044 patients treated with capcitabine. INTERPRETATION: We found no benefit from increasing the dose density of the anthracycline component of chemotherapy. However, capecitabine could be used in place of CMF without significant loss of efficacy and with improved quality of life. FUNDING: Cancer Research UK, Amgen, Pfizer, and Roche.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Breast Neoplasms/drug therapy , Carcinoma/drug therapy , Epirubicin/administration & dosage , Neoplasm Recurrence, Local , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Breast Neoplasms, Male/drug therapy , Breast Neoplasms, Male/surgery , Capecitabine/administration & dosage , Capecitabine/adverse effects , Carcinoma/secondary , Carcinoma/surgery , Chemotherapy, Adjuvant/methods , Cyclophosphamide/administration & dosage , Cyclophosphamide/adverse effects , Diarrhea/chemically induced , Disease-Free Survival , Epirubicin/adverse effects , Fatigue/chemically induced , Female , Filgrastim , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Follow-Up Studies , Granulocyte Colony-Stimulating Factor/administration & dosage , Hand-Foot Syndrome/etiology , Humans , Infections/chemically induced , Male , Methotrexate/administration & dosage , Methotrexate/adverse effects , Middle Aged , Neoplasm Recurrence, Local/diagnosis , Neutropenia/chemically induced , Polyethylene Glycols , Quality of Life , Recombinant Proteins/administration & dosage , Survival Rate , Time FactorsABSTRACT
Motor axons in peripheral nerves have the capacity to regenerate after injury. However, full functional motor recovery rarely occurs clinically, and this depends on the nature and location of the injury. Recent preclinical findings suggest that there may be a time after nerve injury where, while regrowth to the muscle successfully occurs, there is nevertheless a failure to re-establish motor function, suggesting a possible critical period for synapse reformation. We have now examined the temporal and anatomical determinants for the re-establishment of motor function after prolonged neuromuscular junction (NMJ) denervation in rats and mice. Using both sciatic transection-resuture and multiple nerve crush models in rats and mice to produce prolonged delays in reinnervation, we show that regenerating fibres reach motor endplates and anatomically fully reform the NMJ even after extended periods of denervation. However, in spite of this remarkably successful anatomical regeneration, after 1 month of denervation there is a consistent failure to re-establish functional recovery, as assessed by behavioural and electrophysiological assays. We conclude that this represents a failure in re-establishment of synaptic function, and the possible mechanisms responsible are discussed, as are their clinical implications.
Subject(s)
Motor Neurons/physiology , Nerve Regeneration , Neuromuscular Junction/physiology , Peripheral Nerve Injuries/rehabilitation , Sciatic Nerve/physiology , Animals , Denervation , Male , Mice , Mice, Inbred C57BL , Peripheral Nerve Injuries/surgery , Rats , Rats, Sprague-Dawley , Recovery of Function , Sciatic Nerve/surgeryABSTRACT
BACKGROUND: The Her2 receptor is overexpressed in up to 25 % of breast cancers and is associated with a poor prognosis. Around half of Her2+ breast cancers also express the estrogen receptor and treatment for such tumours can involve both endocrine and Her2-targeted therapies. However, despite preclinical data supporting the effectiveness of these agents, responses can vary widely in the clinical setting. In light of the increasing evidence pointing to the interplay between the tumour and its extracellular microenvironment as a significant determinant of therapeutic sensitivity and response here we investigated the impact of 3D matrix culture of breast cancer cells on their therapeutic sensitivity. METHODS: A 3D Matrigel-based culture system was established and optimized for the growth of ER+/Her2+ breast cancer cell models. Growth of cells in response to trastuzumab and endocrine agents in 3D culture versus routine monolayer culture were assessed using cell counting and Ki67 staining. Endogenous and trastuzumab-modulated signalling pathway activity in 2D and 3D cultures were assessed using Western blotting. RESULTS: Breast cancer cells in 3D culture displayed an attenuated response to both endocrine agents and trastuzumab compared with cells cultured in traditional 2D monolayers. Underlying this phenomenon was an apparent matrix-induced shift from AKT to MAPK signalling; consequently, suppression of MAPK in 3D cultures restores therapeutic response. CONCLUSION: These data suggest that breast cancer cells in 3D culture display a reduced sensitivity to therapeutic agents which may be mediated by internal MAPK-mediated signalling. Targeting of adaptive pathways that maintain growth in 3D culture may represent an effective strategy to improve therapeutic response clinically.
Subject(s)
Breast Neoplasms/metabolism , Cell Culture Techniques/methods , Extracellular Signal-Regulated MAP Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , Antineoplastic Agents, Hormonal/pharmacology , Blotting, Western , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Extracellular Matrix , Female , Humans , Immunohistochemistry , Receptor, ErbB-2/biosynthesis , Signal Transduction/physiology , Trastuzumab/pharmacology , Tumor Microenvironment/physiologyABSTRACT
BACKGROUND: Chromosomal instability (CIN) has been shown to be associated with drug resistance and poor clinical outcome in several cancer types. However, in oestrogen receptor (ER)-negative breast cancer we have previously demonstrated that extreme CIN is associated with improved clinical outcome, consistent with a negative impact of CIN on tumour fitness and growth. The aim of this current study was to validate this finding using previously defined CIN thresholds in a much larger prospective cohort from a randomised, controlled, clinical trial. PATIENTS AND METHODS: As a surrogate measurement of CIN, dual centromeric fluorescence in situ hybridisation was performed for both chromosomes 2 and 15 on 1173 tumours from the breast cancer TACT trial (CRUK01/001). Each tumour was scored manually and the mean percentage of cells deviating from the modal centromere number was used to define four CIN groups (MCD1-4), where tumours in the MCD4 group were defined as having extreme CIN. RESULTS: In a multivariate analysis of disease-free survival, with a median follow-up of 91 months, increasing CIN was associated with improved outcome in patients with ER-negative cancer (P trend = 0.03). A similar pattern was seen in ER-negative/HER2-negative cancers (Ptrend = 0.007). CONCLUSIONS: This prospective validation cohort study further substantiated the association between extreme CIN and improved outcome in ER-negative breast cancers. Identifying such patients with extreme CIN may help distinguish good from poor prognostic groups, and therefore support treatment and risk stratification in this aggressive breast cancer subtype.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers, Tumor/metabolism , Breast Neoplasms/genetics , Breast Neoplasms/mortality , Chromosomal Instability , Receptors, Estrogen/metabolism , Adult , Aged , Aged, 80 and over , Anthracyclines/administration & dosage , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Female , Follow-Up Studies , Humans , Immunoenzyme Techniques , In Situ Hybridization, Fluorescence , Middle Aged , Neoplasm Grading , Neoplasm Staging , Prognosis , Prospective Studies , Receptor, ErbB-2/metabolism , Receptors, Progesterone/metabolism , Survival Rate , Taxoids/administration & dosage , Young AdultABSTRACT
BACKGROUND: Bisphosphonates are routinely used in the treatment of metastatic bone disease from breast cancer to reduce pain and bone destruction. Zoledronic acid given by intravenous infusion has been widely used, but places a substantial logistical burden on both patient and hospital. As a result, the use of oral ibandronic acid has increased, despite the absence of comparative data. In the ZICE trial, we compared oral ibandronic acid with intravenous zoledronic acid for the treatment of metastatic breast cancer to bone. METHODS: This phase 3, open-label, parallel group active-controlled, multicentre, randomised, non-inferiority phase 3 study was done in 99 UK hospitals. Eligibility criteria included at least one radiologically confirmed bone metastasis from a histologically confirmed breast cancer. Patients with ECOG performance status 0 to 2 and clinical decision to treat with bisphosphonates within 3 months of randomisation were randomly assigned to receive 96 weeks of treatment with either intravenous zoledronic acid at 4 mg every 3-4 weeks or oral ibandronic acid 50 mg daily. Randomisation (1:1) was done via a central computerised system within stratified block sizes of four. Randomisation was stratified on whether patients had current or planned treatment with chemotherapy; current or planned treatment with hormone therapy; and whether they had a previous skeletal-related event within the last 3 months or had planned radiotherapy treatment to the bone or planned orthopaedic surgery due to bone metastases. The primary non-inferiority endpoint was the frequency and timing of skeletal-related events over 96 weeks, analysed using a per-protocol analysis. All active (non-withdrawn) patients have now reached the 96-week timepoint and the trial is now in long-term follow-up. The trial is registered with ClinicalTrials.gov, number NCT00326820. FINDINGS: Between Jan 13, 2006, and Oct 4, 2010, 705 patients were randomly assigned to receive ibandronic acid and 699 to receive zoledronic acid; three patients withdrew immediately after randomisation. The per-protocol analysis included 654 patients in the ibandronic acid group and 672 in the zoledronic acid group. Annual rates of skeletal-related events were 0·499 (95% CI 0·454-0·549) with ibandronic acid and 0·435 (0·393-0·480) with zoledronic acid; the rate ratio for skeletal-related events was 1·148 (95% CI 0·967-1·362). The upper CI was greater than the margin of non-inferiority of 1·08; therefore, we could not reject the null hypothesis that ibandronic acid was inferior to zoledronic acid. More patients in the zoledronic acid group had renal toxic effects than in the ibandronic acid group (226 [32%] of 697 vs 172 [24%] of 704) but rates of osteonecrosis of the jaw were low in both groups (nine [1%] of 697 vs five [<1%] of 704). The most common grade 3 or 4 adverse events were fatigue (97 [14%] of 697 patients allocated zoledronic acid vs 98 [14%] of 704 allocated ibandronic acid), increased bone pain (91 [corrected] [13%] vs 85 [corrected] [12%]), joint pain (41 [corrected] [6%] vs 38 [5%]), infection (31 [5%] vs 23 [corrected] [3%]), and nausea or vomiting (38 [5%] vs 41 [6%]). INTERPRETATION: Our results suggest that zoledronic acid is preferable to ibandronic acid in preventing skeletal-related events caused by bone metastases. However, both drugs have acceptable side-effect profiles and the oral formulation is more convenient, and could still be considered if the patient has a strong preference or if difficulties occur with intravenous infusions. FUNDING: Roche Products Ltd (educational grant), supported by National Institute for Health Research Cancer Network, following endorsement by Cancer Research UK (CRUKE/04/022).
Subject(s)
Bone Density Conservation Agents/administration & dosage , Bone Neoplasms/drug therapy , Bone Neoplasms/secondary , Breast Neoplasms/pathology , Diphosphonates/administration & dosage , Imidazoles/administration & dosage , Administration, Oral , Aged , Bone Neoplasms/mortality , Diphosphonates/adverse effects , Female , Humans , Ibandronic Acid , Imidazoles/adverse effects , Infusions, Intravenous , Male , Middle Aged , Zoledronic AcidABSTRACT
BACKGROUND: The role of adjuvant bisphosphonates in early breast cancer is uncertain. We therefore did a large randomised trial to investigate the effect of the adjuvant use of zoledronic acid on disease-free survival (DFS) in high-risk patients with early breast cancer. METHODS: In the AZURE trial, an open-label, international, multicentre, randomised, controlled, parallel-group phase 3 trial, women (age ≥18 years) with stage II or III breast cancer were randomly assigned (1:1) by a central automated 24-h computer-generated telephone minimisation system (balanced for number of involved axillary lymph nodes, tumour stage, oestrogen receptor status, type and timing of systemic therapy, menopausal status, statin use, and treatment centre) to receive standard adjuvant systemic treatment alone (control group) or with 4 mg intravenous zoledronic acid every 3-4 weeks for six doses, then every 3 months for eight doses, followed by every 6 months for five doses, for a total of 5 years of treatment. The primary endpoint was disease-free survival (DFS). Secondary endpoints were invasive DFS (IDFS), overall survival, time to bone metastases, time to distant recurrence, and subgroup analyses of variables included in the randomisation. All patients have completed study treatment. Results from the intention-to-treat final analysis of this fully recruited study are presented after a median follow-up of 84 months (IQR 66-93). This final efficacy analysis was planned to take place after 940 DFS events. This trial is registered with ClinicalTrials.gov, NCT00072020. FINDINGS: 3360 women were recruited from 174 centres in seven countries between Sept 4, 2003, and Feb 16, 2006. The number of DFS events did not differ between groups: 493 in the control group and 473 in the zoledronic acid group (adjusted hazard ratio [HR] 0·94, 95% CI 0·82-1·06; p=0·30). IDFS (HR 0·93, 95% CI 0·82-1·05; p=0·22), overall survival (0·93, 0·81-1·08; p=0·37), and distant recurrences (0·93, 0·81-1·07; p=0·29) were much the same in both groups. Zoledronic acid reduced the development of bone metastases, both as a first event (HR 0·78, 95% CI 0·63-0·96; p=0·020) and at any time during follow-up (0·81, 0·68-0·97; p=0·022). The effects of zoledronic acid on DFS were not affected by oestrogen-receptor status. However, zoledronic acid improved IDFS in those who were over 5 years since menopause at trial entry (n=1041; HR 0·77, 95% CI 0·63-0·96) but not in all other (premenopause, perimenopause, and unknown status) menopausal groups (n=2318; HR 1·03, 95% CI 0·89-1·20). 33 cases of suspected osteonecrosis of the jaw have been reported, with 26 confirmed on central review, all in the zoledronic acid group (1·7%, 95% CI 1·0-2·4). INTERPRETATION: These results suggest no overall benefit from the addition of zoledronic acid to standard adjuvant treatments for early breast cancer. However, zoledronic acid does reduce the development of bone metastases and, for women with established menopause, improved disease outcomes. FUNDING: Novartis Global and NIHR Cancer Research Network.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bone Density Conservation Agents/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/mortality , Diphosphonates/therapeutic use , Imidazoles/therapeutic use , Adult , Aged , Aged, 80 and over , Breast Neoplasms/pathology , Chemotherapy, Adjuvant , Confidence Intervals , Disease-Free Survival , Dose-Response Relationship, Drug , Drug Administration Schedule , Early Detection of Cancer , Female , Follow-Up Studies , Humans , Infusions, Intravenous , International Cooperation , Kaplan-Meier Estimate , Middle Aged , Neoplasm Invasiveness/pathology , Neoplasm Staging , Prospective Studies , Survival Rate , Treatment Outcome , Zoledronic AcidABSTRACT
BACKGROUND: Adjuvant trastuzumab with chemotherapy is standard treatment for HER2-positive breast cancer, defined as either HER2 IHC3+ or IHC2+ and FISH amplified. The aim of this study was to investigate the degree to which HER2 amplification in terms of HER2 gene copy numbers in HER2+IHC2+ cancers affected the outcome in a community setting. METHODS: Case records of 311 consecutive patients with early breast cancer presenting between 1st January 2005 and 31st December 2008 were reviewed. Progression-free survival and overall survival were calculated with the Kaplan-Meier method using STATA 13. RESULTS: Among 3+ cases (n=230) 163 received T vs 67 no-T. Among 2+ cases (n=81) 59 received T vs 22 no-T. Among 59 IHC2+-treated cases n=28 had an average of >12, n=13 had >6 to <12, and n=18 had >2 to <6 HER2 gene copies, respectively. The time of progression and overall survival of high and low copy number patients was similar and better than the intermediate copy number and the untreated cohorts. CONCLUSIONS: High HER2 copy number (>12) appears to be associated with consistently better response compared with patients with intermediate HER2 copy numbers (6-12). In light of emerging data of patients showing insensivity to trastuzumab therapy, we propose that the HER2 gene copy number value should be included as an additional indicator for stratifying both the management and the follow-up of breast cancer patients.
Subject(s)
Antibodies, Monoclonal, Humanized/administration & dosage , Breast Neoplasms/drug therapy , Gene Dosage , Receptor, ErbB-2/genetics , Adult , Aged , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Chemotherapy, Adjuvant , Disease-Free Survival , Female , Humans , In Situ Hybridization, Fluorescence , Middle Aged , Neoplasm Staging , Trastuzumab , Treatment Outcome , United KingdomABSTRACT
BACKGROUND: Data suggest that the adjuvant use of bisphosphonates reduces rates of recurrence and death in patients with early-stage breast cancer. We conducted a study to determine whether treatment with zoledronic acid, in addition to standard adjuvant therapy, would improve disease outcomes in such patients. METHODS: In this open-label phase 3 study, we randomly assigned 3360 patients to receive standard adjuvant systemic therapy either with or without zoledronic acid. The zoledronic acid was administered every 3 to 4 weeks for 6 doses and then every 3 to 6 months to complete 5 years of treatment. The primary end point of the study was disease-free survival. A second interim analysis revealed that a prespecified boundary for lack of benefit had been crossed. RESULTS: At a median follow-up of 59 months, there was no significant between-group difference in the primary end point, with a rate of disease-free survival of 77% in each group (adjusted hazard ratio in the zoledronic acid group, 0.98; 95% confidence interval [CI], 0.85 to 1.13; P=0.79). Disease recurrence or death occurred in 377 patients in the zoledronic acid group and 375 of those in the control group. The numbers of deaths--243 in the zoledronic acid group and 276 in the control group--were also similar, resulting in rates of overall survival of 85.4% in the zoledronic acid group and 83.1% in the control group (adjusted hazard ratio, 0.85; 95% CI, 0.72 to 1.01; P=0.07). In the zoledronic acid group, there were 17 confirmed cases of osteonecrosis of the jaw (cumulative incidence, 1.1%; 95% CI, 0.6 to 1.7; P<0.001) and 9 suspected cases; there were no cases in the control group. Rates of other adverse effects were similar in the two study groups. CONCLUSIONS: These findings do not support the routine use of zoledronic acid in the adjuvant management of breast cancer. (Funded by Novartis Pharmaceuticals and the National Cancer Research Network; AZURE Current Controlled Trials number, ISRCTN79831382.).
Subject(s)
Bone Density Conservation Agents/therapeutic use , Breast Neoplasms/drug therapy , Diphosphonates/therapeutic use , Antineoplastic Agents/therapeutic use , Bone Density Conservation Agents/adverse effects , Breast Neoplasms/surgery , Chemotherapy, Adjuvant , Diphosphonates/adverse effects , Disease-Free Survival , Female , Humans , Imidazoles , Kaplan-Meier Estimate , Osteonecrosis/chemically induced , Zoledronic AcidABSTRACT
The TACT trial is the largest study assessing the benefit of taxanes as part of adjuvant therapy for early breast cancer. The goal of this translational study was to clarify the predictive and prognostic value of Tau within the TACT trial. Tissue microarrays (TMA) were available from 3,610 patients. ER, PR, HER2 from the TACT trial and Tau protein expression was determined by immunohistochemistry on duplicate TMAs. Two parallel scoring systems were generated for Tau expression ('dichotomised' vs. 'combined' score). The positivity rate of Tau expression was 50 % in the trial population (n = 2,483). Tau expression correlated positively with ER (p < 0.001) and PR status (p < 0.001); but negatively with histological grade (p < 0.001) and HER2 status (p < 0.001). Analyses with either scoring systems for Tau expression demonstrated no significant interaction between Tau expression and efficacy of docetaxel. Contrary to the hypothesis that taxane benefit would be enriched in Tau negative/low patients, the only groups with a suggestion of a reduced event rate in the taxane group were the HER2-positive, Tau positive subgroups. Tau expression was seen to be a prognostic factor on univariate analysis associated with an improved DFS, independent of the treatment group (p < 0.001). It had no prognostic value in ER-negative tumours and the weak prognostic effect of Tau in ER-positive tumours (p = 0.02) diminished, when considering ER as an ordinal variable. On multivariable analyses, Tau had no prognostic value in either group. In addition, no significant interaction between Tau expression and benefit from docetaxel in patients within the PR-positive and negative subsets was seen. This is now the second large adjuvant study, and the first with quantitative analysis of ER and Tau expression, failing to show an association between Tau and taxane benefit with limited utility as a prognostic marker for Tau in ER-positive early breast cancer patients.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , tau Proteins/metabolism , Adult , Aged , Biomarkers, Tumor/metabolism , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Chemotherapy, Adjuvant , Cyclophosphamide/administration & dosage , Docetaxel , Epirubicin/administration & dosage , Female , Fluorouracil/administration & dosage , Humans , Methotrexate/administration & dosage , Middle Aged , Prognosis , Receptor, ErbB-2/metabolism , Receptors, Estrogen/metabolism , Receptors, Progesterone/metabolism , Taxoids/administration & dosageABSTRACT
BACKGROUND: Subcutaneous trastuzumab has shown non-inferior efficacy and a similar pharmacokinetic and safety profile when compared with intravenous trastuzumab in patients with HER2-positive early breast cancer. We assessed patient preference for either subcutaneous or intravenous trastuzumab in the international, randomised PrefHer study. METHODS: Eligible patients were women aged 18 years or older with HER2-positive, histologically confirmed primary invasive breast adenocarcinoma, no evidence of residual, locally recurrent, or metastatic disease after completion of surgery and chemotherapy (neoadjuvant or adjuvant), an Eastern Cooperative Oncology Group performance status of 0 or 1, and a baseline left-ventricular ejection fraction of 55% or more before the first dose of trastuzumab. Radiotherapy or hormone therapy was allowed. Patients were randomised (randomly permuted blocks of four) to receive four cycles of 600 mg fixed-dose subcutaneous adjuvant trastuzumab via a single-use injection device or hand-held syringe followed by four cycles of standard intravenous trastuzumab, or the reverse sequence. Randomisation was stratified by de-novo versus non-de-novo use of intravenous trastuzumab. The primary endpoint was the proportion of patients indicating an overall preference for subcutaneous or intravenous trastuzumab, assessed by patient interview in the evaluable intention-to-treat (ITT) population (patients who completed both interviews and had at least one administration of both subcutaneous and intravenous trastuzumab). Data collection for PrefHer is ongoing. This study is registered with ClinicalTrials.gov, number NCT01401166. FINDINGS: 124 patients were randomly allocated to receive subcutaneous followed by intravenous trastuzumab, and 124 to receive the reverse sequence. 117 patients in the subcutaneous first group and 119 in the intravenous first group were included in the evaluable ITT population. Subcutaneous trastuzumab via the single-use injection device was preferred by 216 patients (91·5%, 95% CI 87·2-94·7; p<0·0001). Only 16 patients preferred intravenous trastuzumab (6·8%, 3·9-10·8), and four had no preference (1·7%, 0·5-4·3). Clinician-reported adverse events occurred in 141 of 242 (58%) patients during the pooled subcutaneous periods and 105 of 241 (44%) patients during the pooled intravenous periods; seven (3%) and five (2%) were grade 3, no patients had a grade 4 or 5 event. The most common grade 3 adverse event was influenza (two [0·8%] patients). INTERPRETATION: Patient preference and safety results from PrefHer, combined with the known non-inferior efficacy and pharmacokinetic and safety profile data, suggest that a fixed dose of 600 mg trastuzumab administered subcutaneously every 3 weeks is a validated, well tolerated treatment option for HER2-positive breast cancer, and is the preferred treatment of patients.
Subject(s)
Antibodies, Monoclonal, Humanized/administration & dosage , Antineoplastic Agents/administration & dosage , Breast Neoplasms/drug therapy , Receptor, ErbB-2/analysis , Administration, Intravenous , Adult , Antibodies, Monoclonal, Humanized/adverse effects , Antineoplastic Agents/adverse effects , Cross-Over Studies , Female , Humans , Injections, Subcutaneous , Intention to Treat Analysis , Middle Aged , TrastuzumabABSTRACT
BACKGROUND: New therapeutic options are needed for patients with heavily pretreated breast cancer. Etirinotecan pegol is a long-acting topoisomerase-I inhibitor designed to provide prolonged tumour-cell exposure to SN38, the active metabolite. We aimed to assess the efficacy and safety of two etirinotecan pegol dosing schedules in patients with previously treated metastatic breast cancer to determine an optimum dosing schedule for phase 3 trials. METHODS: In this randomised, two-stage, open-label phase 2 trial, we recruited patients aged 18 years or older who had received taxane therapy and undergone two or fewer previous chemotherapy regimens for metastatic breast cancer, with an Eastern Cooperative Oncology Group performance status of 0 or 1, from 18 sites in three countries. Eligible patients were randomly assigned (1:1) to etirinotecan pegol 145 mg/m(2) every 14 days or every 21 days. The primary endpoint was the proportion of patients with a confirmed objective response as defined by Response Evaluation Criteria in Solid Tumors version 1.0, analysed by intention to treat. Safety was assessed in all patients who received at least one dose of study drug. FINDINGS: 70 patients (35 in each group) were randomly assigned to treatment between Feb 17, 2009 and April 13, 2010. Of the 70 patients, 20 (29%; 95% CI 18·4-40·6) achieved an objective response (two [3%] had a complete response and 18 [26%] had a partial response). Ten patients on the 14-day schedule achieved an objective response (29%; 95% CI 14·6-46·3; eight partial responses, two complete responses) as did ten on the 21-day schedule (29%; 95% CI 14·6-46·3; all partial responses). The most common grade 3 or worse adverse events were delayed diarrhoea (seven [20%] of 35 patients on the 14-day schedule vs eight [23%] of 35 patients on the 21-day schedule), fatigue (five [14%] vs three [9%]), neutropenia (four [11%] vs four [11%]), and dehydration (three [9%] vs four [11%]); 14 [20%] patients discontinued treatment because of drug-related toxicity. There were two possible drug-related deaths (acute renal failure and septic shock) in the 14-day group; other drug-related serious adverse events reported by more than one patient included ten [14%] patients with diarrhoea (six [17%] patients on the 14-day schedule vs four [11%] on the 21-day schedule), six [9%] with dehydration (two [6%] vs four [11%]), two [3%] with nausea (two [6%] vs none), and two [3%] with vomiting (two [6%] vs none). INTERPRETATION: On the basis of the overall clinical data, pharmacokinetics, and tolerability profile, etirinotecan pegol 145 mg/m(2) every 21 days has been selected for a phase 3 trial against treatment of physician's choice in patients with advanced breast cancer.