Publications by authors named "McEwen R"

Purpose: Here, we report the sensitivity of a personalized, tumor-informed circulating tumor DNA (ctDNA) assay (Signatera) for detection of molecular relapse during long-term follow-up of patients with breast cancer.

Methods: A total of 156 patients with primary breast cancer were monitored clinically for up to 12 years after surgery and adjuvant chemotherapy. Semiannual blood samples were prospectively collected, and analyzed retrospectively to detect residual disease by ultradeep sequencing using ctDNA assays, developed from primary tumor whole-exome sequencing data.

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  • - The PI3K-AKT pathway is often active in breast cancer, and inhibitors targeting this pathway, like capivasertib and AZD8186, are used in treatments, but the reasons for resistance to these therapies aren't well understood on a broad scale.
  • - CRISPR screenings identified key genes that lead to treatment resistance, revealing that reactivation of PI3K-AKT-mTOR signaling is the primary mechanism, while deletion of certain genes can either confer resistance or increase sensitivity to these drugs.
  • - Loss of Mcl-1 enhances the effectiveness of PI3K-AKT inhibitors by promoting faster cell death, and combining Mcl-1 inhibitors with PI3K-AKT inhibitors shows promise for overcoming resistance in various breast
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  • A study was conducted to assess a comprehensive behavior change intervention aimed at reducing unnecessary antibiotic use in hospitals by encouraging prescribers to make appropriate decisions during clinical reviews.
  • The research utilized a randomized controlled trial across multiple hospitals in the UK, tracking outcomes such as antibiotic dosage and patient mortality within 30 days post-admission through electronic health records and audits.
  • The effectiveness of the intervention was analyzed using time series methods and random-effects meta-analysis, with the study now completed and registered for validation.
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Purpose: To examine the prevalence and dynamics of circulating tumor DNA (ctDNA) and its association with metastatic recurrence in patients with high-risk early-stage hormone receptor-positive breast cancer (HR+ BC) more than 5 years from diagnosis.

Methods: We enrolled 103 patients with high-risk stage II-III HR+ BC diagnosed more than 5 years prior without clinical evidence of recurrence. We performed whole-exome sequencing (WES) on primary tumor tissue to identify somatic mutations tracked via a personalized, tumor-informed ctDNA test to detect minimal residual disease (MRD).

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We describe a new liquid tissue stamping method called poly-synchronous surface extraction (PSSE) that utilizes an omniphobic substrate patterned with hydrophilic surface energy traps (SETs), which when wet with a solvent form a dense microdroplet array. When contacted with a tissue sample, each droplet locally extracts analytes from the tissue surface, which subsequentially can be analyzed by matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-IMS) or ambient ionization-MS techniques. Optimization of the patterned surface with six different solvents was carried out to increase the droplet density, height, and reproducibility of volume deposition.

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Background: Neoadjuvant chemotherapy is often used prior to surgical resection for oesophageal adenocarcinoma but remains ineffective in a high proportion of patients. The histological Mandard tumour regression grade is used to determine chemoresponse but is not available at the time of treatment decision-making. The aim of this cohort study was to identify factors that predict chemotherapy response prior to surgery.

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We present a one-step fabrication method for a new multiplexed electrospray emitter with nine parallel micronozzles. The nozzles were formed by wet chemical etching of the end of a microstructured silica fiber containing nine 10 μm flow channels. By carefully adjusting the water flow through the channels while etching, we controlled the shape of the conical micronozzles and were able to obtain conditions under which the micronozzles, together with the flow channels, formed optical micro-axicon lenses.

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Durvalumab is a programmed death-ligand 1 (PD-L1) inhibitor with clinical activity in advanced urothelial cancer (AUC). AUC is characterized by several recurrent targetable genomic alterations. This study ( NCT02546661 , BISCAY) combined durvalumab with relevant targeted therapies in biomarker-selected chemotherapy-refractory AUC populations including: (1) fibroblast growth factor receptor (FGFR) inhibitors in tumors with FGFR DNA alterations (FGFRm); (2) pharmacological inhibitor of the enzyme poly-ADP ribose polymerase (PARP) in tumors with and without DNA homologous recombination repair deficiency (HRRm); and (3) TORC1/2 inhibitors in tumors with DNA alteration to the mTOR/PI3K pathway.

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  • * A Phase I study tested the combination of oral capivasertib and fulvestrant on patients with PTEN-mutant ER+ MBC, revealing a clinical benefit rate of 17% in treatment-naive patients and 42% in those previously treated with fulvestrant.
  • * The study found that treatment was generally tolerable, with notable adverse events like diarrhea and rash occurring in 32% of patients, and highlighted differences in genetic mutations between treatment-naive and pretreated groups.
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Background: Mutations in STK11 (STK11m) and frequently co-occurring KRAS mutations (KRASm/STK11m) are associated with poor survival in metastatic NSCLC (mNSCLC) immuno-oncology trials. There are limited data regarding the prognostic significance of these mutations in a real-world setting.

Methods: This retrospective cohort study analyzed de-identified electronic medical records from the Flatiron Clinico-Genomic database to identify patients with mNSCLC who had initiated first-line immunotherapy (IO; alone or in combination) or chemotherapy under routine care between January 1, 2013 and June 30, 2017.

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Background: Prognostication in oesophageal cancer on the basis of preoperative variables is challenging. Many of the accepted predictors of survival are only derived after surgical treatment and may be influenced by neoadjuvant therapy. This study aims to explore the relationship between pre-treatment endoscopic tumour morphology and postoperative survival.

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  • The study investigates the effectiveness and safety of capivasertib, an oral AKT inhibitor, for treating estrogen receptor-positive metastatic breast cancer (MBC) with specific activating mutations, conducted in a phase I clinical trial.
  • Out of 63 patients, the overall response rate was 20% for capivasertib alone and 36% for those on capivasertib combined with fulvestrant, suggesting better outcomes with the combination therapy.
  • Results showed that the combination therapy was generally better tolerated than monotherapy, with fewer severe side effects, indicating a viable treatment option for patients who previously showed disease progression.
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Purpose: There are several agents in early clinical trials targeting components of the adenosine pathway including A2AR and CD73. The identification of cancers with a significant adenosine drive is critical to understand the potential for these molecules. However, it is challenging to measure tumor adenosine levels at scale, thus novel, clinically tractable biomarkers are needed.

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  • The study aimed to assess the safety and effectiveness of combining the AKT inhibitor capivasertib with paclitaxel in treating patients with triple-negative breast cancer (TNBC).
  • The randomized phase II trial involved 140 women with untreated metastatic TNBC, revealing a median progression-free survival of 5.9 months for the capivasertib group compared to 4.2 months for the placebo group.
  • The combination treatment also showed a significant increase in overall survival, with a median of 19.1 months for capivasertib plus paclitaxel versus 12.6 months for the placebo, particularly benefiting patients with specific tumor alterations.
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Tumours defective in the DNA homologous recombination repair pathway can be effectively treated with poly (ADP-ribose) polymerase (PARP) inhibitors; these have proven effective in clinical trials in patients with gene function-defective cancers. However, resistance observed in both pre-clinical and clinical studies is likely to impact on this treatment strategy. Over-expression of phosphoglycoprotein (P-gp) has been previously suggested as a mechanism of resistance to the PARP inhibitor olaparib in mouse models of -mutant breast cancer.

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  • The study investigated how changes in circulating tumor DNA (ctDNA) levels can predict long-term outcomes in patients with estrogen receptor-positive metastatic breast cancer undergoing treatment with paclitaxel and an AKT inhibitor, capivasertib.
  • Researchers analyzed ctDNA samples from a clinical trial to determine if early suppression of ctDNA could serve as a reliable early indicator of patient outcomes, specifically progression-free survival (PFS).
  • Results indicated that ctDNA suppression after just 4 weeks of treatment was significantly associated with longer PFS, suggesting that monitoring ctDNA dynamics could be an effective method for predicting treatment efficacy in cancer patients.
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The PI3Kα signaling pathway is frequently hyper-activated in breast cancer (BrCa), as a result of mutations/amplifications in oncogenes (e.g. ), decreased function in tumor suppressors (e.

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The cyclin dependent kinase (CDK)-retinoblastoma (RB)-E2F pathway plays a critical role in the control of cell cycle in estrogen receptor-positive (ER) breast cancer. Small-molecule inhibitors of CDK4/6 have shown promise in this tumor type in combination with hormonal therapies, reflecting the particular dependence of this subtype of cancer on cyclin D1 and E2F transcription factors. mTOR inhibitors have also shown potential in clinical trials in this disease setting.

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Despite wishes for and benefits of home deaths, a discrepancy between preferred and actual location of death persists. Provision of home care may be an effective policy response to support home deaths. Using the population-based mortality follow-back study conducted in Nova Scotia, we investigated the associations between home death and formal care at home and between home death and the type of formal care at home.

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PTEN-null tumors become dependent on the PI3Kβ isoform and can be targeted by molecules such as the selective PI3Kβ inhibitor AZD8186. However, beyond the modulation of the canonical PI3K pathway, the consequences of inhibiting PI3Kβ are poorly defined. To determine the broader impact of AZD8186 in PTEN-null tumors, we performed a genome-wide RNA-seq analysis of PTEN-null triple-negative breast tumor xenografts treated with AZD8186.

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  • This study investigated the effectiveness of AZD5363, a drug that inhibits the AKT kinase, specifically in patients with cancer caused by AKT1 E17K mutations, which are found in various cancers but at low rates.! -
  • In a trial involving 58 patients with advanced cancer, those with AKT1 E17K mutations experienced a median progression-free survival (PFS) of 5.5 months, with variations depending on cancer type, highlighting the drug's potential effectiveness.! -
  • The study also identified that specific genetic changes and lower levels of AKT1 E17K in the blood were linked to better treatment responses, while common side effects included hyperglycemia, diarrhea, and rash,
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Mutant-selective EGFR tyrosine kinase inhibitors (TKI), such as osimertinib, are active agents for the treatment of -mutant lung cancer. Specifically, these agents can overcome the effects of the T790M mutation, which mediates resistance to first- and second-generation EGFR TKI, and recent clinical trials have documented their efficacy in patients with -mutant lung cancer. Despite promising results, therapeutic efficacy is limited by the development of acquired resistance.

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Genomic profiling of tumours in patients in clinical trials enables rapid testing of multiple hypotheses to confirm which genomic events determine likely responder groups for targeted agents. A key challenge of this new capability is defining which specific genomic events should be classified as 'actionable' (that is, potentially responsive to a targeted therapy), especially when looking for early indications of patient subgroups likely to be responsive to new drugs. This Opinion article discusses some of the different approaches being taken in early clinical development to define actionable mutations, and describes our strategy to address this challenge in early-stage exploratory clinical trials.

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Accurate variant calling in next generation sequencing (NGS) is critical to understand cancer genomes better. Here we present VarDict, a novel and versatile variant caller for both DNA- and RNA-sequencing data. VarDict simultaneously calls SNV, MNV, InDels, complex and structural variants, expanding the detected genetic driver landscape of tumors.

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Selective phosphoinositide 3-kinase (PI3K)/AKT/mTOR inhibitors are currently under evaluation in clinical studies. To identify tumor types that are sensitive to PI3K pathway inhibitors we screened compounds targeting PI3Kα/δ (AZD8835), PI3Kβ/δ (AZD8186), AKT (AZD5363) and mTORC1/2 (AZD2014) against a cancer cell line panel (971 cell lines). There was an enrichment of hematological malignancies that were sensitive to AKT and mTOR inhibition, with the greatest degree of sensitivity observed in T-cell acute lymphoblastic leukemia (T-ALL).

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