Publications by authors named "Jean Powers"

Background: In PTEN-loss models, the phosphatidylinositol 3-kinase (PI3K)/AKT and androgen receptor signaling pathways cross-regulate by reciprocal feedback whereby inhibition of one activates the other, creating a rationale for co-targeting. We studied the irreversible, pan-isoform inhibitor of Class I PI-3K PX-866 singly (part A) and with abiraterone acetate (AA) in patients on AA with rising prostate-specific antigen (PSA) (part B).

Patients And Methods: The primary endpoint was lack of progression at 12 weeks.

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Unlabelled: Combining mammalian target of rapamycin (mTOR) inhibitors and vinca alkaloids has shown therapeutic synergy in xenograft models of pediatric cancers. This phase I study assessed safety and toxicity of temsirolimus in combination with vinblastine in children.

Procedure: Patients ≥ 1 and ≤ 18 years with recurrent/refractory solid or CNS tumors were eligible.

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Purpose: MET and AXL mediate resistance to EGFR TKI in NSCLC. Foretinib, a MET/RON/AXL/TIE-2/VEGFR kinase inhibitor may overcome EGFR kinase resistance. This dose escalation study combined foretinib and erlotinib in advanced pretreated NSCLC patients.

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AT7519M is a small molecule inhibitor of cyclin-dependent kinases 1, 2, 4, 5, and 9 with in vitro activity against lymphoid malignancies. In two concurrent Phase II trials, we evaluated AT7519M in relapsed or refractory chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL) using the recommended Phase II dosing of 27 mg/m twice weekly for 2 of every 3 weeks. Primary objective was objective response rate (ORR).

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Background: Glioblastoma (GBM) is the most aggressive malignancy of the central nervous system in adults. Increased activity of the phosphatidylinositol-3-OH kinase (PI3K) signal transduction pathway is common. We performed a phase II study using PX-866, an oral PI3K inhibitor, in participants with recurrent GBM.

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The insulin-like growth factor receptor is a potential target in small-cell lung cancer. We conducted a phase I study of cisplatin, etoposide plus dalotuzumab. Two dose levels of dalotuzumab (DL1 5 mg/kg, DL2 10mg/kg IV weekly) were evaluated in combination with cisplatin (25 mg/m²) and etoposide (100 mg/m²) IV D1-3, every 21 days, for patients with chemotherapy-naive extensive-stage small-cell lung cancer.

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Bortezomib and gemcitabine have each shown activity as single agents in mantle cell lymphoma (MCL), which is incurable. The purpose of this phase II study was to determine the efficacy and safety of the previously unstudied combination of bortezomib and gemcitabine in patients with relapsed or refractory MCL. Patients were eligible if they had relapsed MCL with 1-3 prior therapies.

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Purpose: To determine the clinical activity of OGX-011, an antisense inhibitor of clusterin, in combination with docetaxel/prednisone in patients with metastatic castration-resistant prostate cancer.

Patients And Methods: Patients were randomly assigned 1:1 to receive docetaxel/prednisone either with (arm A) or without (arm B) OGX-011 640 mg intravenously weekly. The primary end point was the proportion of patients with a prostate-specific antigen (PSA) decline of ≥ 50% from baseline, with the experimental therapy being considered of interest if the proportion of patients with a PSA decline was more than 60%.

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Bortezomib is a proteasome inhibitor that induces apoptosis in primary Waldenström's macroglobulinemia (WM) cells and WM cell lines. To date, 3 clinical trials of single-agent bortezomib in WM have been published. Of the 64 patients pooled from these studies (most with relapsed/refractory disease), a 25% or greater reduction of IgM was achieved in 78%-85%.

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Purpose: Cediranib is a potent oral inhibitor of the tyrosine kinase activity associated with all subtypes of vascular endothelial growth factor receptor. Purposes of this study were to determine the recommended phase II dose of cediranib in combination with standard doses of modified FOLFOX-6 (mFOLFOX-6), and the tolerability, safety, pharmacokinetics, and antitumor activity of this combination in patients with untreated metastatic colorectal cancer.

Experimental Design: Cediranib was administered daily orally at a starting dose of 30 mg and escalated to 45 mg daily, and mFOLFOX-6 was repeated every 14 days.

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Purpose: Clusterin is an antiapoptotic protein activated in response to cellular stress. OGX-011 is a second-generation antisense oligonucleotide that inhibits clusterin expression. The primary objective of this phase II trial was to assess the safety and efficacy of the combination of OGX-011 and docetaxel for metastatic breast cancer.

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Introduction: Cediranib, a potent vascular endothelial growth factor inhibitor, demonstrated broad pre-clinical anti-tumour activity. This study evaluated escalating cediranib doses with combination chemotherapy in advanced non-small cell lung cancer patients.

Methods: Patients received cisplatin 80 mg/m(2) on day 1 and gemcitabine 1250 mg/m(2) on days 1 and 8 of a 3-week cycle, and daily oral cediranib at either 30 mg or 45 mg.

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Purpose: We have observed cavitation of lesions in clinical trials of an angiogenesis inhibitor combined with chemotherapy for non-small-cell lung cancer (NSCLC). We hypothesized that cavitation might alter response assessment in such clinical trials.

Patients And Methods: We performed a retrospective radiologic review of patients with NSCLC enrolled onto three National Cancer Institute of Canada Clinical Trials Group (NCIC CTG) trials of platinum-based chemotherapy with or without a small-molecule angiogenesis inhibitor (vascular endothelial growth factor receptor inhibitor [VEGFRI]).

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Purpose: AZD2171 is a potent inhibitor of vascular endothelial growth factor receptors that showed broad antitumor activity in preclinical models. Doses of up to 45 mg/d of AZD2171 are tolerable when administered alone. This study evaluated escalating doses of AZD2171 in combination with standard chemotherapy in patients with advanced non-small-cell lung cancer.

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Purpose: Clusterin is a cytoprotective chaperone protein that promotes cell survival and confers broad-spectrum treatment resistance. OGX-011 is a 2'-methoxyethyl-modified phosphorothioate antisense oligonucleotide that is complementary to clusterin mRNA, has a prolonged tissue half life, enhances drug efficacy in xenograft models, and reduces clusterin expression in humans with a biologically effective dose of 640 mg. The objective of this study was to determine a recommended phase II dose of OGX-011 in combination with docetaxel.

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Purpose: To evaluate the efficacy and toxicity of single-agent bortezomib in Waldenström's macroglobulinemia (WM).

Patients And Methods: Symptomatic WM patients, untreated or previously treated, received bortezomib 1.3 mg/m2 intravenously days 1, 4, 8, and 11 on a 21-day cycle until two cycles past complete response (CR), stable disease (SD) attained, progression (PD), or unacceptable toxicity.

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Background: Clusterin is a cytoprotective chaperone protein that promotes cell survival and confers broad-spectrum treatment resistance. OGX-011 is a 2'-methoxyethyl modified phosphorothioate antisense oligonucleotide that is complementary to clusterin mRNA and has been reported to inhibit clusterin expression and enhance drug efficacy in xenograft models. The primary objective of this clinical study was to determine a biologically effective dose of OGX-011 that would inhibit clusterin expression in human cancer.

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Background: T900607 is a novel tubulin active agent which disrupts microtubule polymerization by a unique mechanism of action. This phase I trial was conducted to determine the maximum tolerated dose, recommended phase II dose, pharmacokinetic properties and toxicities of this agent.

Patients And Methods: Patients with advanced and/or metastatic solid malignancies were enrolled, for an open dose escalation of T900607 administered intravenously over 30 minutes every 21-days.

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Purpose: Protein farnesylation by farnesyltransferase (FTase) is required for membrane localization and effective signal transduction by G-proteins, including Ras. Lonafarnib inhibits FTase and has shown antitumor activity in both preclinical and clinical settings. As disturbances in Ras signaling pathways have been implicated in the pathogenesis of transitional cell carcinoma (TCC), the antitumor activity of lonafarnib was studied in a National Cancer Institute of Canada Clinical Trials Group Phase II trial in patients with previously treated TCC.

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We studied the activity of T138067-sodium in patients with malignant gliomas. T138067-sodium is a unique new chemotherapy agent that inhibits microtubule formation by binding irreversibly and specifically to beta(1), beta(2)and beta(4) isotypes of 3-tubulin, causing cell arrest at G(2)/M and inducing apoptosis. Patients with recurrent anaplastic astrocytoma or glioblastoma multiforme were treated intravenously with 330 mg/m(2) of T138067-sodium weekly.

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The goals of this study were to evaluate the validity of the visual analogue scale (VAS) for young children and to compare a newly developed method of teaching children to use a VAS with one used in our previous studies. It was hypothesized that the new method would increase the number of children who understand the VAS and correctly mark their responses on the VAS line. The association between child's age and ability to understand the VAS was also evaluated.

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Purpose: To determine the response rate and toxicity of flavopiridol in patients with previously untreated or relapsed mantle-cell lymphoma.

Patients And Methods: Adult patients with previously untreated or in first or second relapse of previously responsive mantle-cell lymphoma were given flavopiridol 50 mg/m2/d by intravenous bolus for 3 consecutive days every 21 days with antidiarrheal prophylaxis. Flavopiridol was continued until disease progression, unacceptable toxicity, or stable disease for four cycles.

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