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1.
EMBO J ; 40(14): e107182, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34086370

RESUMO

Integration of signalling downstream of individual receptor tyrosine kinases (RTKs) is crucial to fine-tune cellular homeostasis during development and in pathological conditions, including breast cancer. However, how signalling integration is regulated and whether the endocytic fate of single receptors controls such signalling integration remains poorly elucidated. Combining quantitative phosphoproteomics and targeted assays, we generated a detailed picture of recycling-dependent fibroblast growth factor (FGF) signalling in breast cancer cells, with a focus on distinct FGF receptors (FGFRs). We discovered reciprocal priming between FGFRs and epidermal growth factor (EGF) receptor (EGFR) that is coordinated at recycling endosomes. FGFR recycling ligands induce EGFR phosphorylation on threonine 693. This phosphorylation event alters both FGFR and EGFR trafficking and primes FGFR-mediated proliferation but not cell invasion. In turn, FGFR signalling primes EGF-mediated outputs via EGFR threonine 693 phosphorylation. This reciprocal priming between distinct families of RTKs from recycling endosomes exemplifies a novel signalling integration hub where recycling endosomes orchestrate cellular behaviour. Therefore, targeting reciprocal priming over individual receptors may improve personalized therapies in breast and other cancers.


Assuntos
Endossomos/metabolismo , Transporte Proteico/fisiologia , Transdução de Sinais/fisiologia , Tirosina/metabolismo , Linhagem Celular Tumoral , Endocitose/fisiologia , Receptores ErbB/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Humanos , Fosforilação/fisiologia
3.
Kidney Int Rep ; 9(4): 1005-1019, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38765580

RESUMO

Introduction: We assess if ultrasound surveillance of newly-created arteriovenous fistulas (AVFs) can predict nonmaturation sufficiently reliably to justify randomized controlled trial (RCT) evaluation of ultrasound-directed salvage intervention. Methods: Consenting adults underwent blinded fortnightly ultrasound scanning of their AVF after creation, with scan characteristics that predicted AVF nonmaturation identified by logistic regression modeling. Results: Of 333 AVFs created, 65.8% matured by 10 weeks. Serial scanning revealed that maturation occurred rapidly, whereas consistently lower fistula flow rates and venous diameters were observed in those that did not mature. Wrist and elbow AVF nonmaturation could be optimally modeled from week 4 ultrasound parameters alone, but with only moderate positive predictive values (PPVs) (wrist, 60.6% [95% confidence interval, CI: 43.9-77.3]; elbow, 66.7% [48.9-84.4]). Moreover, 40 (70.2%) of the 57 AVFs that thrombosed by week 10 had already failed by the week 4 scan, thus limiting the potential of salvage procedures initiated by that scan's findings to alter overall maturation rates. Modeling of the early ultrasound characteristics could also predict primary patency failure at 6 months; however, that model performed poorly at predicting assisted primary failure (those AVFs that failed despite a salvage attempt), partly because patency of at-risk AVFs was maintained by successful salvage performed without recourse to the early scan data. Conclusion: Early ultrasound surveillance may predict fistula maturation, but is likely, at best, to result in only very modest improvements in fistula patency. Power calculations suggest that an impractically large number of participants (>1700) would be required for formal RCT evaluation.

4.
Health Technol Assess ; 28(24): 1-54, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38768043

RESUMO

Background: Arteriovenous fistulas are considered the best option for haemodialysis provision, but as many as 30% fail to mature or suffer early failure. Objective: To assess the feasibility of performing a randomised controlled trial that examines whether, by informing early and effective salvage intervention of fistulas that would otherwise fail, Doppler ultrasound surveillance of developing arteriovenous fistulas improves longer-term arteriovenous fistula patency. Design: A prospective multicentre observational cohort study (the 'SONAR' study). Setting: Seventeen haemodialysis centres in the UK. Participants: Consenting adults with end-stage renal disease who were scheduled to have an arteriovenous fistula created. Intervention: Participants underwent Doppler ultrasound surveillance of their arteriovenous fistulas at 2, 4, 6 and 10 weeks after creation, with clinical teams blinded to the ultrasound surveillance findings. Main outcome measures: Fistula maturation at week 10 defined according to ultrasound surveillance parameters of representative venous diameter and blood flow (wrist arteriovenous fistulas: ≥ 4 mm and > 400 ml/minute; elbow arteriovenous fistulas: ≥ 5 mm and > 500 ml/minute). Mixed multivariable logistic regression modelling of the early ultrasound scan data was used to predict arteriovenous fistula non-maturation by 10 weeks and fistula failure at 6 months. Results: A total of 333 arteriovenous fistulas were created during the study window (47.7% wrist, 52.3% elbow). By 2 weeks, 37 (11.1%) arteriovenous fistulas had failed (thrombosed), but by 10 weeks, 219 of 333 (65.8%) of created arteriovenous fistulas had reached maturity (60.4% wrist, 67.2% elbow). Persistently lower flow rates and venous diameters were observed in those fistulas that did not mature. Models for arteriovenous fistulas' non-maturation could be optimally constructed using the week 4 scan data, with fistula venous diameter and flow rate the most significant variables in explaining wrist fistula maturity failure (positive predictive value 60.6%, 95% confidence interval 43.9% to 77.3%), whereas resistance index and flow rate were most significant for elbow arteriovenous fistulas (positive predictive value 66.7%, 95% confidence interval 48.9% to 84.4%). In contrast to non-maturation, both models predicted fistula maturation much more reliably [negative predictive values of 95.4% (95% confidence interval 91.0% to 99.8%) and 95.6% (95% confidence interval 91.8% to 99.4%) for wrist and elbow, respectively]. Additional follow-up and modelling on a subset (n = 192) of the original SONAR cohort (the SONAR-12M study) revealed the rates of primary, assisted primary and secondary patency arteriovenous fistulas at 6 months were 76.5, 80.7 and 83.3, respectively. Fistula vein size, flow rate and resistance index could identify primary patency failure at 6 months, with similar predictive power as for 10-week arteriovenous fistula maturity failure, but with wide confidence intervals for wrist (positive predictive value 72.7%, 95% confidence interval 46.4% to 99.0%) and elbow (positive predictive value 57.1%, 95% confidence interval 20.5% to 93.8%). These models, moreover, performed poorly at identifying assisted primary and secondary patency failure, likely because a subset of those arteriovenous fistulas identified on ultrasound surveillance as at risk underwent subsequent successful salvage intervention without recourse to early ultrasound data. Conclusions: Although early ultrasound can predict fistula maturation and longer-term patency very effectively, it was only moderately good at identifying those fistulas likely to remain immature or to fail within 6 months. Allied to the better- than-expected fistula patency rates achieved (that are further improved by successful salvage), we estimate that a randomised controlled trial comparing early ultrasound-guided intervention against standard care would require at least 1300 fistulas and would achieve only minimal patient benefit. Trial Registration: This trial is registered as ISRCTN36033877 and ISRCTN17399438. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR135572) and is published in full in Health Technology Assessment; Vol. 28, No. 24. See the NIHR Funding and Awards website for further award information.


For people with advanced kidney disease, haemodialysis is best provided by an 'arteriovenous fistula', which is created surgically by joining a vein onto an artery at the wrist or elbow. However, these take about 2 months to develop fully ('mature'), and as many as 3 out of 10 fail to do so. We asked whether we could use early ultrasound scanning of the fistula to identify those that are unlikely to mature. This would allow us to decide whether it would be practical to run a large, randomised trial to find out if using early ultrasound allows us to 'rescue' fistulas that would otherwise fail. We invited adults to undergo serial ultrasound scanning of their fistula in the first few weeks after it was created. We then analysed whether we could use the data from the early scans to identify those fistulas that were not going to mature by week 10. Of the 333 fistulas that were created, about two-thirds reached maturity by week 10. We found that an ultrasound scan 4 weeks after fistula creation could reliably identify those fistulas that were going to mature. However, of those fistulas predicted to fail, about one-third did eventually mature without further intervention, and even without knowing what the early scans showed, another third were successfully rescued by surgery or X-ray-guided treatment at a later stage. Performing an early ultrasound scan on a fistula can provide reassurance that it will mature and deliver trouble-free dialysis. However, because scans are poor at identifying fistulas that are unlikely to mature, we would not recommend their use to justify early surgery or X-ray-guided treatment in the expectation that this will improve outcomes.


Assuntos
Derivação Arteriovenosa Cirúrgica , Falência Renal Crônica , Diálise Renal , Ultrassonografia Doppler , Grau de Desobstrução Vascular , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Estudos Prospectivos , Falência Renal Crônica/terapia , Idoso , Reino Unido , Adulto
5.
J Periodontol ; 92(7): 1030-1035, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33155320

RESUMO

BACKGROUND: To determine the level of perceived pain after different types of periodontal/oral surgical procedures, and the differences in patients' selection of pain management, over the counter (OTC) versus opioid, based on procedure type. METHODS: Patients undergoing surgical procedures were asked to complete a pain questionnaire at four time points: 1) before surgery 2) first dose of analgesic at home, 3) 24 hours postoperatively, and 4) 72 hours postoperatively. The questionnaire consisted of numerical and descriptive scales to describe the perceived pain. RESULTS: A total of 198 patients completed the questionnaire. All surgical procedures were grouped into five major categories: bone augmentation procedures (11% BAP), teeth extractions (26% EXT), surgical implant placement (25% IP), mucogingival surgeries (21% MGS), and pocket elimination procedures (17%). IP surgery was associated with significantly less pain compared with MGS and EXT (P <0.05). There was a statistically significant difference for taking any medication based on type of surgical procedure at 24 hours (P <0.05). CONCLUSIONS: IP is associated with significantly lower perceived pain compared with EXT and MGS surgery. Analgesic consumption was generally parallel to pain perception. A considerable number of patients elected to control the post-surgical pain using OTC medication up to 72 hours. Periodontal/oral surgery procedures vary in the amount of perceived postoperative pain. Tailoring postoperative medications to the type of periodontal/oral surgery performed will help prevent overprescribing of opioids.


Assuntos
Analgésicos Opioides , Procedimentos Cirúrgicos Bucais , Analgésicos Opioides/uso terapêutico , Humanos , Manejo da Dor , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle
6.
Front Cell Dev Biol ; 7: 395, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32039208

RESUMO

Breast cancer incidence is increasing worldwide with more than 600,000 deaths reported in 2018 alone. In current practice treatment options for breast cancer patients consists of surgery, chemotherapy, radiotherapy or targeting of classical markers of breast cancer subtype: estrogen receptor (ER) and HER2. However, these treatments fail to prevent recurrence and metastasis. Improved understanding of breast cancer and metastasis biology will help uncover novel biomarkers and therapeutic opportunities to improve patient stratification and treatment. We will first provide an overview of current methods and models used to study breast cancer biology, focusing on 2D and 3D cell culture, including organoids, and on in vivo models such as the MMTV mouse model and patient-derived xenografts (PDX). Next, genomic, transcriptomic, and proteomic approaches and their integration will be considered in the context of breast cancer susceptibility, breast cancer drivers, and therapeutic response and resistance to treatment. Finally, we will discuss how 'Omics datasets in combination with traditional breast cancer models are useful for generating insights into breast cancer biology, for suggesting individual treatments in precision oncology, and for creating data repositories to undergo further meta-analysis. System biology has the potential to catalyze the next great leap forward in treatment options for breast cancer patients.

8.
Nat Commun ; 4: 2680, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24157944

RESUMO

T and B cell receptor loci undergo combinatorial rearrangement, generating a diverse immune receptor repertoire, which is vital for recognition of potential antigens. Here we use a multiplex PCR with a mixture of primers targeting the rearranged variable and joining segments to capture receptor diversity. Differential hybridization kinetics can introduce significant amplification biases that alter the composition of sequence libraries prepared by multiplex PCR. Using a synthetic immune receptor repertoire, we identify and minimize such biases and computationally remove residual bias after sequencing. We apply this method to a multiplex T cell receptor gamma sequencing assay. To demonstrate accuracy in a biological setting, we apply the method to monitor minimal residual disease in acute lymphoblastic leukaemia patients. A similar methodology can be extended to any adaptive immune locus.


Assuntos
Sondas de DNA/química , Reação em Cadeia da Polimerase Multiplex/métodos , Neoplasia Residual/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos T/genética , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/patologia , Primers do DNA , Expressão Gênica , Biblioteca Gênica , Humanos , Imunofenotipagem , Reação em Cadeia da Polimerase Multiplex/normas , Neoplasia Residual/diagnóstico , Neoplasia Residual/imunologia , Neoplasia Residual/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Receptores de Antígenos de Linfócitos B/classificação , Receptores de Antígenos de Linfócitos B/imunologia , Receptores de Antígenos de Linfócitos T/classificação , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/patologia
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