Publications by authors named "Simon Pacey"

The prognosis in the setting of metastatic castration-resistant prostate cancer patients (mCRPC) remains limited. Therefore, novel treatment strategies remain an unmet need. Antibody-drug conjugates (ADC) emerged as a new drug concept with the potential to deliver a cytotoxic payload with limited off-target toxicity and potentially bystander effect.

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Background: Active surveillance (AS) is a preferred management option for men with prostate cancer with favourable prognosis. However, nearly half of men on AS switch to treatment within 5 years, so therapeutic strategies to prevent or delay disease progression could be considered. The androgen receptor is the pre-eminent oncogenic driver in prostate cancer.

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Current evidence suggests that plasma cell-free DNA (cfDNA) is fragmented around a mode of 166 bp. Data supporting this view has been mainly acquired through the analysis of double-stranded cfDNA. The characteristics and diagnostic potential of single-stranded and damaged double-stranded cfDNA in healthy individuals and cancer patients remain unclear.

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Introduction: Pegargiminase (ADI-PEG 20; ADI) degrades arginine and potentiates pemetrexed (Pem) cytotoxicity in argininosuccinate synthetase 1 (ASS1)-deficient malignant pleural mesothelioma (MPM). We conducted a phase 1 dose-expansion study at the recommended phase 2 dose of ADI-PEG 20 with Pem and cisplatin (ADIPemCis), to further evaluate arginine-lowering therapy in ASS1-deficient MPM and explore the mechanisms of resistance.

Methods: A total of 32 patients with ASS1-deficient MPM (11 epithelioid; 10 biphasic;11 sarcomatoid) who were chemonaive received weekly intramuscular pegargiminase (36 mg/m) with Pem (500 mg/m) and cisplatin (75 mg/m) intravenously, every 3 weeks (six cycles maximum).

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Clear cell renal cell carcinoma (ccRCC) contains cancer stem-like cells (CSCs) that express CD133 (ccRCC-CD133). CSCs are rarely in cell cycle and, as nonproliferating cells, resist most chemotherapeutic agents. Previously, we reported that tumor necrosis factor receptor-2 (TNFR2) signaling promotes the cell cycle entry of ccRCC-CD133CSCs, rendering them susceptible to cell-cycle-dependent chemotherapeutics.

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Purpose: Patients with recurrent high-grade gliomas (HGG) are usually managed with alkylating chemotherapy ± bevacizumab. However, prognosis remains very poor. Preclinically, we showed that HGGs are a target for arginine depletion with pegargiminase (ADI-PEG20) due to epimutations of argininosuccinate synthetase () and/or argininosuccinate lyase ().

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Existing methods to improve detection of circulating tumor DNA (ctDNA) have focused on genomic alterations but have rarely considered the biological properties of plasma cell-free DNA (cfDNA). We hypothesized that differences in fragment lengths of circulating DNA could be exploited to enhance sensitivity for detecting the presence of ctDNA and for noninvasive genomic analysis of cancer. We surveyed ctDNA fragment sizes in 344 plasma samples from 200 patients with cancer using low-pass whole-genome sequencing (0.

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Macroautophagy/autophagy is an evolutionarily conserved catabolic pathway whose modulation has been linked to diverse disease states, including age-associated disorders. Conventional and conditional whole-body knockout mouse models of key autophagy genes display perinatal death and lethal neurotoxicity, respectively, limiting their applications for in vivo studies. Here, we have developed an inducible shRNA mouse model targeting Atg5, allowing us to dynamically inhibit autophagy in vivo, termed ATG5i mice.

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Purpose Pegylated arginine deiminase (ADI-PEG 20) depletes essential amino acid levels in argininosuccinate synthetase 1 (ASS1) -negative tumors by converting arginine to citrulline and ammonia. The main aim of this study was to determine the recommended dose, safety, and tolerability of ADI-PEG 20, cisplatin, and pemetrexed in patients with ASS1-deficient malignant pleural mesothelioma (MPM) or non-small-cell lung cancer (NSCLC). Patients and Methods Using a 3 + 3 + 3 dose-escalation study, nine chemotherapy-naïve patients (five MPM, four NSCLC) received weekly ADI-PEG 20 doses of 18 mg/m, 27 mg/m, or 36 mg/m, together with pemetrexed 500 mg/m and cisplatin 75 mg/m which were given every three weeks (maximum of six cycles).

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While early treatment of primary prostate cancer is very effective, the incidence of primary prostate cancer continues to rise and therefore the detection of men with high-risk non-metastatic prostate cancer and their subsequent management is becoming increasingly important. There continues to be no molecularly-targeted or chemotherapeutic options with proven, statistically significant survival benefit in this setting. However, there are indications that further risk stratification using molecular features could potentially help distinguish indolent from aggressive prostate cancer, ultimately providing biological markers that could guide a more personalised approach to therapy selection.

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Improvements in genomic and molecular methods are expanding the range of potential applications for circulating tumour DNA (ctDNA), both in a research setting and as a 'liquid biopsy' for cancer management. Proof-of-principle studies have demonstrated the translational potential of ctDNA for prognostication, molecular profiling and monitoring. The field is now in an exciting transitional period in which ctDNA analysis is beginning to be applied clinically, although there is still much to learn about the biology of cell-free DNA.

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Compared to normal kidney, renal clear cell carcinomas (ccRCC) contain increased numbers of interstitial, non-hematopoietic CD133+cells that express stem cell markers and exhibit low rates of proliferation. These cells fail to form tumors upon transplantation but support tumor formation by differentiated malignant cells. We hypothesized that killing of ccRCC CD133+ (RCCCD133+) cells by cytotoxic agents might be enhanced by inducing them to divide.

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Discovery of activating mutations in EGFR and their use as predictive biomarkers to tailor patient therapy with EGFR tyrosine kinase inhibitors (TKIs) has revolutionised treatment of patients with advanced EGFR-mutant non-small-cell lung cancer (NSCLC). At present, first-line treatment with EGFR TKIs (gefitinib, erlotinib, and afatinib) has been approved for patients harbouring exon 19 deletions or exon 21 (Leu858Arg) substitution EGFR mutations. These agents improve response rates, time to progression, and overall survival.

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Background: This open-label phase I dose-escalation study investigated the safety, efficacy, pharmacokinetics (PK), and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) effects of the oral angiokinase inhibitor nintedanib in patients with advanced solid tumors.

Methods: Nintedanib was administered once daily continuously, starting at 100 mg and later amended to allow evaluation of 250 mg b.i.

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Purpose: This phase I expansion study assessed safety, pharmacodynamic effects, and antitumor activity of RO4987655, a pure MEK inhibitor, in selected patients with advanced solid tumor.

Experimental Design: We undertook a multicenter phase I two-part study (dose escalation and cohort expansion). Here, we present the part 2 expansion that included melanoma, non-small cell lung cancer (NSCLC), and colorectal cancer with oral RO4987655 administered continuously at recommended doses of 8.

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Background: Everolimus (mammalian target of rapmaycin (mTOR) inhibitor) and dovitinib (vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF-2) inhibitor) demonstrate activity in metastatic clear cell renal cancer. The combination of these agents has a broad spectrum of relevant activity. The combination is explored in this phase Ib study.

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Purpose: A phase I study to define toxicity and recommend a phase II dose of the HSP90 inhibitor alvespimycin (17-DMAG; 17-dimethylaminoethylamino-17-demethoxygeldanamycin). Secondary endpoints included evaluation of pharmacokinetic profile, tumor response, and definition of a biologically effective dose (BED).

Patients And Methods: Patients with advanced solid cancers were treated with weekly, intravenous (i.

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Purpose: A Phase II study to screen for anti-melanoma activity of the heat shock protein 90 (HSP90) inhibitor, 17-AAG (17-allylamino-17-demethoxygeldanamycin) was performed. The primary endpoint was the rate of disease stabilisation in patients with progressive, metastatic melanoma treated with 17-AAG. Secondary endpoints were to determine: the toxicity of 17-AAG, the duration of response(s), median survival and further study the pharmacokinetics and pharmacodynamics of 17-AAG.

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Purpose: Heat shock protein (Hsp) 90 inhibition affects the Raf kinase signaling pathway and could enhance antitumor effects of sorafenib, a Raf kinase inhibitor. The combination of sorafenib and tanespimycin [17-allyl-amino-geldanamycin (17-AAG); NSC 330507/KOS-953] was evaluated in a phase I trial with the primary objective of defining a phase II dose.

Patients And Methods: The dose cohorts consisted of fixed continuous oral dosing of 400 mg sorafenib twice daily, starting at 14 days before tanespimycin, which was administered intravenously at escalating doses (starting at 300 mg/m,(2) with 50 mg/m(2) increments), on days 1, 8, and 15 in a 28-day cycle.

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Aim: Phase II multi-disease randomized discontinuation trial to assess the safety and efficacy of sorafenib including patients with advanced soft tissue sarcoma (STS).

Methods: Sorafenib (400 mg twice daily) was initially administered for 12 weeks. Patients with: ≥25% tumour shrinkage continued sorafenib; ≥25% tumour growth discontinued; other patients were randomized and received sorafenib or placebo.

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Heat shock protein 90 (HSP90) inhibitors, such as 17-allylamino-17-demethoxygeldanamycin (17-AAG, tanespimycin), which is currently in phase II/phase III clinical trials, are promising new anticancer agents. Here, we explored acquired resistance to HSP90 inhibitors in glioblastoma (GB), a primary brain tumor with poor prognosis. GB cells were exposed continuously to increased 17-AAG concentrations.

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Purpose: To determine the safety, maximum tolerated dose, and pharmacokinetic-pharmacodynamic profile of a histone deacetylase inhibitor, LAQ824, in patients with advanced malignancy.

Patients And Methods: LAQ824 was administered i.v.

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