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1.
BMC Public Health ; 24(1): 1147, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38658961

ABSTRACT

BACKGROUND: Evidence on workplace bullying and harassment (WBH) in the UK has not used probability-sample surveys with robust mental health assessments. This study aimed to profile the prevalence and nature of WBH in England, identify inequalities in exposure, and quantify adjusted associations with mental health. METHODS: Data were from the 2014 Adult Psychiatric Morbidity Survey, a cross-sectional probability-sample survey of the household population in England. Criteria for inclusion in the secondary analysis were being aged 16-70 years and in paid work in the past month (n = 3838). Common mental disorders (CMDs) were assessed using the Clinical Interview Schedule-Revised and mental wellbeing using the Warwick-Edinburgh Mental Wellbeing Scale. Analyses were weighted. We examined associations between past-year WBH and current CMD using multivariable regression modelling, adjusting for sociodemographic factors. Interaction terms tested for gender differences in associations. The study received ethical approval (ETH21220-299). RESULTS: One in ten employees (10.6%, n = 444/3838) reported past-year experience of WBH, with rates higher in women (12.2%, n = 284/2189), those of mixed, multiple, and other ethnicity (21.0%, n = 15/92), and people in debt (15.2%, n = 50/281) or living in cold homes (14.6%, n = 42/234). Most commonly identified perpetrators of WBH were line managers (53.6%, n = 244/444) or colleagues (42.8%, n = 194/444). Excessive criticism (49.3%, n = 212/444), verbal abuse (42.6%, n = 187/444), and humiliation (31.4%, n = 142/444) were the most common types. WBH was associated with all indicators of poor mental health, including CMD (adjusted odds ratio [aOR] 2.65, 95% CI 2.02-3.49), and 11 of 14 mental wellbeing indicators, including lower levels of confidence (aOR 0.57, 0.46-0.72) and closeness to others (aOR 0.57, 0.46-0.72). Patterns of association between WBH and mental health were similar in men and women. CONCLUSIONS: These findings reinforce a need for more cohesive UK legislation against WBH; guidance on recognition of bullying behaviours for employees, managers, and human resources, focusing on prevention and early intervention, and increased awareness of the impact of WBH on mental health among health service practitioners. Limitations include reliance on cross-sectional data collected before pandemic-related and other changes in workplace practices. Longitudinal data are needed to improve evidence on causality and the longevity of mental health impacts.


Subject(s)
Bullying , Mental Disorders , Workplace , Humans , Cross-Sectional Studies , Male , Female , Adult , Bullying/statistics & numerical data , Bullying/psychology , Middle Aged , England/epidemiology , Adolescent , Young Adult , Prevalence , Mental Disorders/epidemiology , Mental Disorders/psychology , Aged , Workplace/psychology , Workplace/statistics & numerical data , Surveys and Questionnaires , Mental Health/statistics & numerical data
2.
Lancet ; 402 Suppl 1: S2, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37997059

ABSTRACT

BACKGROUND: Evidence on workplace bullying and harassment (WBH) in the UK has not used probability-sample surveys with robust mental health assessments. This study aimed to profile the prevalence and nature of WBH in England, identify inequalities in WBH exposure, and quantify adjusted associations with mental health. METHODS: Data were from the 2014 Adult Psychiatric Morbidity Survey, a cross-sectional probability-sample survey of the household population in England, interviewed with verbal informed consent. Criteria for inclusion in the secondary analysis were being aged 16-70 years and in paid work in the past month (n=3838). Common mental disorders were assessed using the Clinical Interview Schedule-Revised and mental wellbeing using the Warwick-Edinburgh Mental Wellbeing Scale. Analyses were weighted. We examined associations between past-year WBH and current common mental disorders using multivariable regression modelling, adjusting for demographic and socioeconomic factors. Interaction terms tested for gender differences in associations. The study received ethics approval (ETH21220-299). FINDINGS: One in ten employees (10·6% (weighted), n=444/3838) reported past-year experience of WBH, with rates higher in women (12·2%, n=284/2189); those of mixed, multiple, and other ethnicity (21·0%, n=15/92); and people in debt (15·2%, n=50/281) or living in cold homes (14·6%, n=42/234). Most commonly identified perpetrators of WBH were line managers (53·6%, n=244/444) or colleagues (42·8%, n=194/444). Excessive criticism (49·3%, n=212/444), verbal abuse (42·6%, n=187/444), and humiliation (31·4%, n=142/444) were the most common types. WBH was associated with all adverse mental health indicators, including common mental disorders (adjusted odds ratio [aOR] 2·65, 95% CI 2·02-3·49), and 11 of 14 mental wellbeing indicators, including lower levels of confidence (aOR 0·57, 0·46-0·72) and of closeness to others (aOR 0·57, 0·46-0·72). Patterns of association between WBH and mental health were similar in men and women. INTERPRETATION: These findings reinforce a need for more cohesive UK legislation at the national level; guidance on recognition of bullying behaviours for employees, managers, and human resources at the organisational level, focusing on prevention and early intervention, and increased awareness of the impact of WBH on mental health among health-service practitioners. Study limitations include reliance on cross-sectional data collected before pandemic-related and other major changes in workplace practices. Longitudinal data are needed to improve evidence on causality and the longevity of mental health impacts. FUNDING: UK Prevention Research Partnership.


Subject(s)
Bullying , Occupational Stress , Adult , Male , Humans , Female , Mental Health , Prevalence , Cross-Sectional Studies , Sampling Studies , Surveys and Questionnaires
3.
Neoplasia ; 43: 100921, 2023 09.
Article in English | MEDLINE | ID: mdl-37603953

ABSTRACT

Constitutional mismatch repair deficiency (CMMRD) is a cancer predisposition syndrome associated with the development of hypermutant pediatric high-grade glioma, and confers a poor prognosis. While therapeutic histone deacetylase (HDAC) inhibition of diffuse intrinsic pontine glioma (DIPG) has been reported; here, we use a clinically relevant biopsy-derived hypermutant DIPG model (PBT-24FH) and a CRISPR-Cas9 induced genetic model to evaluate the efficacy of HDAC inhibition against hypermutant DIPG. We screened PBT-24FH cells for sensitivity to a panel of HDAC inhibitors (HDACis) in vitro, identifying two HDACis associated with low nanomolar IC50s, quisinostat (27 nM) and romidepsin (2 nM). In vivo, quisinostat proved more efficacious, inducing near-complete tumor regression in a PBT-24FH flank model. RNA sequencing revealed significant quisinostat-driven changes in gene expression, including upregulation of neural and pro-inflammatory genes. To validate the observed potency of quisinostat in vivo against additional hypermutant DIPG models, we tested quisinostat in genetically-induced mismatch repair (MMR)-deficient DIPG flank tumors, demonstrating that loss of MMR function increases sensitivity to quisinostat in vivo. Here, we establish the preclinical efficacy of quisinostat against hypermutant DIPG, supporting further investigation of epigenetic targeting of hypermutant pediatric cancers with the potential for clinical translation. These findings support further investigation of HDAC inhibitors against pontine high-grade gliomas, beyond only those with histone mutations, as well as against other hypermutant central nervous system tumors.


Subject(s)
Diffuse Intrinsic Pontine Glioma , Glioma , Humans , Child , Diffuse Intrinsic Pontine Glioma/drug therapy , Diffuse Intrinsic Pontine Glioma/genetics , Histone Deacetylase Inhibitors/pharmacology , Histones , Hydroxamic Acids , Glioma/drug therapy , Glioma/genetics
4.
Ann Emerg Med ; 81(6): 667-676, 2023 06.
Article in English | MEDLINE | ID: mdl-36841658

ABSTRACT

STUDY OBJECTIVE: Bougie use during emergency tracheal intubation has not been well studied in children. METHODS: This was a 10-year observational study of pediatric intubations (<18 years of age) in the emergency department (ED) of an academic institution. Bougie training and use are standard in our ED, including for emergency medicine residents. Study data were collected by a combination of charts and video reviews. We compare first-attempt intubation success and procedural complications between pediatric patients with and without bougie use during tracheal intubation in the ED. In addition, we evaluate the independent association of bougie use with first-attempt intubation success using multivariable logistic regression. RESULTS: We collected data on intubation success and bougie use for 195 pediatric patients over more than 10 years. On the first tracheal intubation attempt, a pediatric bougie was used in 126 patients (65%). Median patient age was 5 years (interquartile range 1.7 to 9) in the bougie group and 1.7 years (interquartile range 0.2 to 5) in the no bougie group. Intubation was successful on the first attempt in 72% of intubations with a bougie versus 78% without a bougie (absolute difference -6%, 95% confidence interval [CI] -19 to 6%); the adjusted odds of first-attempt success with a bougie were 0.54 (95% CI 0.24 to 1.19). A procedural complication occurred for 38% of patients in the bougie group versus 51% in the no bougie group (-13%, 95% CI -27% to 2%). Two neonates, one in each group, experienced a potential injury to the airway or lower respiratory tract. CONCLUSION: In an academic ED where the bougie is commonly used, bougie use in children was not associated with procedural success or complications. Our study suggests that a randomized clinical trial is needed to determine the effect of bougie use during emergency pediatric intubation.


Subject(s)
Critical Illness , Intubation, Intratracheal , Infant, Newborn , Humans , Child , Infant , Child, Preschool , Critical Illness/therapy , Intubation, Intratracheal/adverse effects , Registries , Emergency Service, Hospital , Logistic Models , Laryngoscopy
5.
Cancer Discov ; 13(1): 114-131, 2023 01 09.
Article in English | MEDLINE | ID: mdl-36259971

ABSTRACT

Diffuse intrinsic pontine glioma (DIPG) remains a fatal brainstem tumor demanding innovative therapies. As B7-H3 (CD276) is expressed on central nervous system (CNS) tumors, we designed B7-H3-specific chimeric antigen receptor (CAR) T cells, confirmed their preclinical efficacy, and opened BrainChild-03 (NCT04185038), a first-in-human phase I trial administering repeated locoregional B7-H3 CAR T cells to children with recurrent/refractory CNS tumors and DIPG. Here, we report the results of the first three evaluable patients with DIPG (including two who enrolled after progression), who received 40 infusions with no dose-limiting toxicities. One patient had sustained clinical and radiographic improvement through 12 months on study. Patients exhibited correlative evidence of local immune activation and persistent cerebrospinal fluid (CSF) B7-H3 CAR T cells. Targeted mass spectrometry of CSF biospecimens revealed modulation of B7-H3 and critical immune analytes (CD14, CD163, CSF-1, CXCL13, and VCAM-1). Our data suggest the feasibility of repeated intracranial B7-H3 CAR T-cell dosing and that intracranial delivery may induce local immune activation. SIGNIFICANCE: This is the first report of repeatedly dosed intracranial B7-H3 CAR T cells for patients with DIPG and includes preliminary tolerability, the detection of CAR T cells in the CSF, CSF cytokine elevations supporting locoregional immune activation, and the feasibility of serial mass spectrometry from both serum and CSF. This article is highlighted in the In This Issue feature, p. 1.


Subject(s)
Brain Stem Neoplasms , Diffuse Intrinsic Pontine Glioma , Humans , B7 Antigens , Brain Stem Neoplasms/therapy , T-Lymphocytes
6.
Neuro Oncol ; 24(9): 1438-1451, 2022 09 01.
Article in English | MEDLINE | ID: mdl-35157764

ABSTRACT

BACKGROUND: Pediatric diffuse midline gliomas (DMGs) are incurable childhood cancers. The imipridone ONC201 has shown early clinical efficacy in a subset of DMGs. However, the anticancer mechanisms of ONC201 and its derivative ONC206 have not been fully described in DMGs. METHODS: DMG models including primary human in vitro (n = 18) and in vivo (murine and zebrafish) models, and patient (n = 20) frozen and FFPE specimens were used. Drug-target engagement was evaluated using in silico ChemPLP and in vitro thermal shift assay. Drug toxicity and neurotoxicity were assessed in zebrafish models. Seahorse XF Cell Mito Stress Test, MitoSOX and TMRM assays, and electron microscopy imaging were used to assess metabolic signatures. Cell lineage differentiation and drug-altered pathways were defined using bulk and single-cell RNA-seq. RESULTS: ONC201 and ONC206 reduce viability of DMG cells in nM concentrations and extend survival of DMG PDX models (ONC201: 117 days, P = .01; ONC206: 113 days, P = .001). ONC206 is 10X more potent than ONC201 in vitro and combination treatment was the most efficacious at prolonging survival in vivo (125 days, P = .02). Thermal shift assay confirmed that both drugs bind to ClpP, with ONC206 exhibiting a higher binding affinity as assessed by in silico ChemPLP. ClpP activation by both drugs results in impaired tumor cell metabolism, mitochondrial damage, ROS production, activation of integrative stress response (ISR), and apoptosis in vitro and in vivo. Strikingly, imipridone treatment triggered a lineage shift from a proliferative, oligodendrocyte precursor-like state to a mature, astrocyte-like state. CONCLUSION: Targeting mitochondrial metabolism and ISR activation effectively impairs DMG tumorigenicity. These results supported the initiation of two pediatric clinical trials (NCT05009992, NCT04732065).


Subject(s)
Antineoplastic Agents , Glioma , Animals , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Cell Lineage , Child , Energy Metabolism , Glioma/drug therapy , Glioma/pathology , Heterocyclic Compounds, 4 or More Rings/therapeutic use , Humans , Mice , Zebrafish
7.
Child Soc ; 35(1): 62-74, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33362362

ABSTRACT

The COVID-19 pandemic has had an enormous impact across the world. In this discussion paper, we examine the effect that lockdown has had on the mental health and well-being of children and young people. We write from a UK perspective in the light of the international evidence. Many of the discussion points raised resonate globally. We discuss how these issues can be dealt with and set out potential solutions as we emerge from this global crisis.

8.
Neuro Oncol ; 23(3): 376-386, 2021 03 25.
Article in English | MEDLINE | ID: mdl-33130903

ABSTRACT

BACKGROUND: Diffuse midline gliomas (DMGs), including diffuse intrinsic pontine gliomas (DIPGs), have a dismal prognosis, with less than 2% surviving 5 years postdiagnosis. The majority of DIPGs and all DMGs harbor mutations altering the epigenetic regulatory histone tail (H3 K27M). Investigations addressing DMG epigenetics have identified a few promising drugs, including the HDAC inhibitor (HDACi) panobinostat. Here, we use clinically relevant DMG models to identify and validate other effective HDACi and their biomarkers of response. METHODS: HDAC inhibitors were tested across biopsy-derived treatment-naïve in vitro and in vivo DMG models with biologically relevant radiation resistance. RNA sequencing was performed to define and compare drug efficacy and to map predictive biomarkers of response. RESULTS: Quisinostat and romidepsin showed efficacy with low nanomolar half-maximal inhibitory concentration (IC50) values (~50 and ~5 nM, respectively). Comparative transcriptome analyses across quisinostat, romidepsin, and panobinostat showed a greater degree of shared biological effects between quisinostat and panobinostat, and less overlap with romidepsin. However, some transcriptional changes were consistent across all 3 drugs at similar biologically effective doses, such as overexpression of troponin T1 slow skeletal type (TNNT1) and downregulation of collagen type 20 alpha 1 chain (COL20A1), identifying these as potential vulnerabilities or on-target biomarkers in DMG. Quisinostat and romidepsin significantly (P < 0.0001) inhibited in vivo tumor growth. CONCLUSIONS: Our data highlight the utility of treatment-naïve biopsy-derived models; establishes quisinostat and romidepsin as effective in vivo; illuminates potential mechanisms and/or biomarkers of DMG cell lethality due to HDAC inhibition; and emphasizes the need for brain tumor-penetrant versions of potentially efficacious agents.


Subject(s)
Brain Stem Neoplasms , Glioma , Biopsy , Glioma/drug therapy , Glioma/genetics , Histones/genetics , Humans , Mutation , Panobinostat
9.
J Exp Neurol ; 1(4): 158-167, 2020 12.
Article in English | MEDLINE | ID: mdl-33768215

ABSTRACT

Diffuse intrinsic pontine glioma (DIPG) is a universally fatal tumor of the brainstem, most commonly affecting young children. Due to its location, surgical resection is not achievable, but consideration of a biopsy has become standard practice at children's hospitals with the appropriate neurosurgical expertise. While the decision to obtain a biopsy should be directed by the presence of atypical radiographic features that call the diagnosis of DIPG into question or the requirement of biopsy tissue for clinical trial enrollment, once this precious tissue is available its use for research should be considered. The majority of DIPG and diffuse midline glioma, H3 K27M-mutant (DMG) models are autopsy-derived or genetically-engineered, each of which has limitations for translational studies, so the use of biopsy tissue for laboratory model development provides an opportunity to create unique model systems. Here, we present a detailed laboratory protocol for the generation of treatment-naïve biopsy-derived DIPG/DMG models.

10.
Article in English | MEDLINE | ID: mdl-30987398

ABSTRACT

Research on cyberbullying amongst students has tended to be conducted separately within specific education institutional contexts, schools, further education (FE) and higher education (HE), neglecting a view that takes account of the entire educational lifespan. The present article addresses this gap in the literature, providing a novel take on examining its nature, social environments, legal consequences and potentially helpful interventions. To facilitate this, the article conceptualises cyberbullying in broad terms, recognising that it can take multiple forms of online and digital practice including: spreading rumours, ridiculing and/or demeaning another person, casting aspirations on the grounds of race, disability, gender, religion or sexual orientation; seeking revenge or deliberately embarrassing a person by posting intimate photos or videos about them without their consent; accessing another's social networking profiles with malicious intent and socially excluding a person from a social network or gaming site. This article demonstrates that harm from cyberbullying is a cause for concern for students at each developmental stage and that there are continuities in its appearance that need to be challenged at each point in the educational lifespan. And inaccurately, by university, the idea that 'nothing can be done' still is one of the main concerns for the victims. The article concludes with five key recommendations for future research and practice across the educational lifespan.


Subject(s)
Crime Victims/statistics & numerical data , Cyberbullying/prevention & control , Cyberbullying/statistics & numerical data , Internet , Schools , Students/statistics & numerical data , Universities , Adolescent , Crime Victims/psychology , Cyberbullying/psychology , Humans , Interpersonal Relations , Social Networking , Students/psychology , Young Adult
11.
Clin Cancer Res ; 25(1): 177-187, 2019 01 01.
Article in English | MEDLINE | ID: mdl-30201762

ABSTRACT

PURPOSE: The ability to locate and remove all malignant lesions during radical prostatectomy leads not only to prevent biochemical recurrence (BCR) and possible side effects but also to improve the life expectancy of patients with prostate cancer. Fluorescence-guided surgery (FGS) has emerged as a technique that uses fluorescence to highlight cancerous cells and guide surgeons to resect tumors in real time. Thus, development of tumor-specific near-infrared (NIR) agents that target biomarkers solely expressed on prostate cancer cells will enable to assess negative tumor margins and affected lymph nodes. EXPERIMENTAL DESIGN: Because PSMA is overexpressed in prostate cancer cells in >90% of the prostate cancer patient population, a prostate-specific membrane antigen (PSMA)-targeted NIR agent (OTL78) was designed and synthesized. Optical properties, in vitro and in vivo specificity, tumor-to-background ratio (TBR), accomplishment of negative surgical tumor margins using FGS, pharmacokinetics (PKs) properties, and preclinical toxicology of OTL78 were then evaluated in requisite models. RESULTS: OTL78 binds to PSMA-expressing cells with high affinity, concentrates selectively to PSMA-positive cancer tissues, and clears rapidly from healthy tissues with a half-time of 17 minutes. It also exhibits an excellent TBR (5:1) as well as safety profile in animals. CONCLUSIONS: OTL78 is an excellent tumor-specific NIR agent for use in fluorescence-guided radical prostatectomy and FGS of other cancers.


Subject(s)
Antigens, Surface/genetics , Fluorescent Dyes/pharmacology , Glutamate Carboxypeptidase II/genetics , Prostatic Neoplasms/diagnostic imaging , Surgery, Computer-Assisted , Animals , Antigens, Surface/isolation & purification , Cell Line, Tumor , Disease Models, Animal , Fluorescence , Fluorescent Dyes/chemistry , Gene Expression Regulation, Neoplastic/genetics , Glutamate Carboxypeptidase II/isolation & purification , Heterografts , Humans , Infrared Rays , Male , Margins of Excision , Optical Imaging , Prostate/surgery , Prostatectomy/methods , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Prostatic Neoplasms/surgery , Spectroscopy, Near-Infrared
12.
Epigenetics Chromatin ; 11(1): 74, 2018 12 21.
Article in English | MEDLINE | ID: mdl-30577869

ABSTRACT

BACKGROUND: Our understanding of eukaryotic gene regulation is limited by the complexity of protein-DNA interactions that comprise the chromatin landscape and by inefficient methods for characterizing these interactions. We recently introduced CUT&RUN, an antibody-targeted nuclease cleavage method that profiles DNA-binding proteins, histones and chromatin-modifying proteins in situ with exceptional sensitivity and resolution. RESULTS: Here, we describe an automated CUT&RUN platform and apply it to characterize the chromatin landscapes of human cells. We find that automated CUT&RUN profiles of histone modifications crisply demarcate active and repressed chromatin regions, and we develop a continuous metric to identify cell-type-specific promoter and enhancer activities. We test the ability of automated CUT&RUN to profile frozen tumor samples and find that our method readily distinguishes two pediatric glioma xenografts by their subtype-specific gene expression programs. CONCLUSIONS: The easy, cost-effective workflow makes automated CUT&RUN an attractive tool for high-throughput characterization of cell types and patient samples.


Subject(s)
Chromatin Immunoprecipitation/methods , Gene Expression Profiling/methods , Binding Sites , Chromatin/genetics , DNA-Binding Proteins/analysis , DNA-Binding Proteins/classification , DNA-Binding Proteins/genetics , Enhancer Elements, Genetic/genetics , Gene Expression Regulation, Neoplastic/genetics , High-Throughput Screening Assays/methods , Histone Code/genetics , Histones/genetics , Humans , In Situ Hybridization/methods , K562 Cells , Promoter Regions, Genetic/genetics , Protein Binding/genetics , Software , Transcription Factors/genetics
13.
J Med Chem ; 61(21): 9637-9646, 2018 11 08.
Article in English | MEDLINE | ID: mdl-30296376

ABSTRACT

Because the most reliable therapy for cancer involves quantitative resection of all diseased tissue, considerable effort has been devoted to improving a surgeon's ability to locate and remove all malignant lesions. With the aid of improved optical imaging equipment, we and others have focused on developing tumor-targeted fluorescent dyes to selectively illuminate cancer nodules during surgery. We describe here the design, synthesis, optical properties, in vitro and in vivo tumor specificity/affinity, pharmacokinetics, preclinical toxicology, and some clinical application of a folate receptor (FR)-targeted NIR dye (OTL38) that concentrates specifically in cancer tissues and clears rapidly from healthy tissues. We demonstrate that OTL38 binds FR-expressing cells with ∼1 nM affinity and eliminates from receptor negative tissues with a half-time of <30 min. We further show that OTL38 enables visualization of malignant lesions at concentrations less than 100-fold those required to elicit signs of toxicity. Since OTL38 also provides excellent tumor contrast in both murine tumor models and human cancer patients, we conclude that OTL38 constitutes an excellent NIR dye for fluorescence-guided resection of malignant lesions in cancer patients.


Subject(s)
Fluorescent Dyes/chemistry , Fluorescent Dyes/metabolism , Folic Acid/chemistry , Folic Acid/metabolism , Infrared Rays , Neoplasms/surgery , Surgery, Computer-Assisted , A549 Cells , Animals , Drug Design , Fluorescence , Fluorescent Dyes/chemical synthesis , Folate Receptors, GPI-Anchored/chemistry , Folate Receptors, GPI-Anchored/metabolism , Folic Acid/chemical synthesis , Humans , KB Cells , Mice , Molecular Docking Simulation , Neoplasms/diagnostic imaging , Neoplasms/metabolism , Neoplasms/pathology , Protein Conformation
14.
Oncogene ; 37(31): 4226-4238, 2018 08.
Article in English | MEDLINE | ID: mdl-29717260

ABSTRACT

While advances in laboratory automation has dramatically increased throughout of compound screening efforts, development of robust cell-based assays in relevant disease models remain resource-intensive and time-consuming, presenting a bottleneck to drug discovery campaigns. To address this issue, we present a modified gene trap approach to efficiently generate pathway-specific reporters that result in a robust "on" signal when the pathway of interest is inhibited. In this proof-of-concept study, we used vemurafenib and trametinib to identify traps that specifically detect inhibition of the mitogen-activated protein kinase (MAPK) pathway in a model of BRAFV600E driven human malignant melanoma. We demonstrate that insertion of our trap into particular loci results in remarkably specific detection of MAPK pathway inhibitors over compounds targeting any other pathway or cellular function. The accuracy of our approach was highlighted in a pilot screen of ~6000 compounds where 40 actives were detected, including 18 MEK, 10 RAF, and 3 ERK inhibitors along with a few compounds representing previously under-characterized inhibitors of the MAPK pathway. One such compound, bafetinib, a second generation BCR/ABL inhibitor, reduced phosphorylation of ERK and when combined with trametinib, both in vitro and in vivo, reduced growth of vemurafenib resistant melanoma cells. While piloted in a model of BRAF-driven melanoma, our results set the stage for using this approach to rapidly generate reporters against any transcriptionally active pathway across a wide variety of disease-relevant cell-based models to expedite drug discovery efforts.


Subject(s)
Antineoplastic Agents/pharmacology , Melanoma/drug therapy , Melanoma/genetics , Skin Neoplasms/drug therapy , Skin Neoplasms/genetics , Animals , Cell Line , Cell Line, Tumor , Drug Discovery/methods , Female , HEK293 Cells , Humans , Mice , Mitogen-Activated Protein Kinases/metabolism , Phosphorylation/drug effects , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins B-raf/metabolism , Pyridones/pharmacology , Pyrimidines/metabolism , Pyrimidinones/pharmacology , Vemurafenib/pharmacology , Melanoma, Cutaneous Malignant
15.
Anticancer Res ; 38(1): 51-60, 2018 01.
Article in English | MEDLINE | ID: mdl-29277756

ABSTRACT

BACKGROUND/AIM: Developments in imaging have improved cancer diagnosis, but identification of malignant cells during surgical resection remains a challenge. The aim of this study was to investigate the pacifastin family of peptides for novel activity targeting tumor cells and the delivery of either imaging or therapeutic agents. MATERIALS AND METHODS: Variants of pacifastin family peptides were generated, chemically modified and tested in human tumor xenografts. RESULTS: A tumor-homing peptide-dye conjugate (THP1) accumulated in tumors in vivo and was internalized into cells. Examination of related peptides revealed residues critical for accumulation and allowed the engineering of improved tumor-targeting variants. A THP1-drug conjugate carrying the microtubule inhibitor, MMAE, showed limited activity in vitro and no difference compared to vehicle control in vivo. CONCLUSION: Although there are some obstacles to developing pacifastin-derived peptides for therapeutic activity, these optimized peptides have great promise for cancer imaging.


Subject(s)
Neoplasms/diagnostic imaging , Peptides/therapeutic use , Proteins , Animals , Autoradiography , Cell Line, Tumor , Cell Survival/drug effects , Humans , Mice, Nude , Microscopy, Confocal , Neoplasms/drug therapy , Peptides/pharmacology , Tubulin Modulators/pharmacology , Tubulin Modulators/therapeutic use
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