Ittmann M.,Baylor College of Medicine |
Ittmann M.,Michael bakey Veterans Affairs Medical Center |
Huang J.,University of California at Los Angeles |
Radaelli E.,University of Milan |
And 15 more authors.
Cancer Research | Year: 2013
Animal models, particularly mouse models, play a central role in the study of the etiology, prevention, and treatment of human prostate cancer. While tissue culture models are extremely useful in understanding the biology of prostate cancer, they cannot recapitulate the complex cellular interactions within the tumor microenvironment that play a key role in cancer initiation and progression. The National Cancer Institute (NCI) Mouse Models of Human Cancers Consortium convened a group of human and veterinary pathologists to review the current animal models of prostate cancer and make recommendations about the pathologic analysis of these models. More than 40 different models with 439 samples were reviewed, including genetically engineered mouse models, xenograft, rat, and canine models. Numerous relevant models have been developed over the past 15 years, and each approach has strengths and weaknesses. Analysis of multiple genetically engineered models has shown that reactive stroma formation is present in all the models developing invasive carcinomas. In addition, numerous models with multiple genetic alterations display aggressive phenotypes characterized by sarcomatoid carcinomas and metastases, which is presumably a histologic manifestation of epithelial-mesenchymal transition. The significant progress in development of improved models of prostate cancer has already accelerated our understanding of thecomplex biology of prostate cancer andpromises to enhance developmentof new approaches to prevention, detection, and treatment of this common malignancy. Cancer Res; 73(9); 2718-36. © 2013 AACR.
Wen P.Y.,Center for Neuro Oncology |
Chang S.M.,University of California at San Francisco |
Lamborn K.R.,University of California at San Francisco |
Kuhn J.G.,University of Texas Health Science Center at San Antonio |
And 18 more authors.
Neuro-Oncology | Year: 2014
Background. Inhibition of epidermal growth factor receptor (EGFR) and the mechanistic target of rapamycin (mTOR) may have synergistic antitumor effects in high-grade glioma patients. Methods. We conducted a phase I/II study of the EGFR inhibitor erlotinib (150 mg/day) and the mTOR inhibitor temsirolimus. Patients initially received temsirolimus 50 mg weekly, and the dose adjusted based on toxicities. In the phase II component, the primary endpoint was 6-month progression-free survival (PFS6) among glioblastoma patients. Results. Twenty-two patients enrolled in phase I, 47 in phase II. Twelve phase I patients treated at the maximum tolerated dosage were included in the phase II cohort for analysis. The maximum tolerated dosage was 15 mg temsirolimus weekly with erlotinib 150 mg daily. Dose-limiting toxicities were rash and mucositis. Among 42 evaluable glioblastoma patients, 12 (29%) achieved stable disease, but there were no responses, and PFS6 was 13%. Among 16 anaplastic glioma patients, 1 (6%) achieved complete response, 1 (6%) partial response, and 2 (12.5%) stable disease, with PFS6 of 8%. Tumor levels of both drugs were low, and posttreatment tissue in 3 patients showed no reduction in the mTOR target phosphorylated (phospho-)S6S235/236 but possible compensatory increase in phospho-AktS473. Presence of EGFR variant III, phospho-EGFR, and EGFR amplification did not correlate with survival, but patients with elevated phospho-extracellular signal-regulated kinase or reduced phosphatase and tensin homolog protein expression had decreased progression-free survival at 4 months.ConclusionBecause of increased toxicity, the maximum tolerated dosage of temsirolimus in combination with erlotinib proved lower than expected. Insufficient tumor drug levels and redundant signaling pathways may partly explain the minimal antitumor activity noted. © 2014 © The Author(s) 2014.
Drappatz J.,Dana-Farber Cancer Institute |
Drappatz J.,Brigham and Women's Hospital |
Drappatz J.,Harvard University |
Norden A.D.,Dana-Farber Cancer Institute |
And 27 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2010
Purpose: Increasing evidence has suggested that angiogenesis inhibition might potentiate the effects of radiotherapy and chemotherapy in patients with glioblastoma (GBM). In addition, epidermal growth factor receptor inhibition might be of therapeutic benefit, because the epidermal growth factor receptor is upregulated in GBM and contributes to radiation resistance. We conducted a Phase I study of vandetanib, an inhibitor of vascular endothelial growth factor receptor 2 and epidermal growth factor receptor, in patients with newly diagnosed GBM combined with RT and temozolomide (TMZ). Methods and Materials: A total of 13 GBM patients were treated with vandetanib, radiotherapy, and concurrent and adjuvant TMZ, using a standard "3 + 3" dose escalation. The maximal tolerated dose was defined as the dose with <1 of 6 dose-limiting toxicities during the first 12 weeks of therapy. The eligible patients were adults with newly diagnosed GBM, Karnofsky performance status of ≥60, normal organ function, who were not taking enzyme-inducing antiepileptic drugs. Results: Of the 13 patients, 6 were treated with vandetanib at a dose of 200mg daily. Of the 6 patients, 3 developed dose-limiting toxicities within the first 12 weeks, including gastrointestinal hemorrhage and thrombocytopenia in 1 patient, neutropenia in 1 patient, and diverticulitis with gastrointestinal perforation in 1 patient. The other 7 patients were treated with 100 mg daily, with no dose-limiting toxicities observed, establishing this dose as the maximal tolerated dose combined with TMZ and RT. Conclusion: Vandetanib can be safely combined with RT and TMZ in GBM patients. A Phase II study in which patients are randomized to vandetanib 100 mg daily with RT and TMZ or RT and TMZ alone is underway. © 2010 Elsevier Inc.
Norden A.D.,Brigham and Women's Hospital |
Norden A.D.,Center for Neuro Oncology |
Norden A.D.,Harvard University |
Ligon K.L.,Brigham and Women's Hospital |
And 33 more authors.
Neurology | Year: 2015
Objective: A subset of meningiomas recur after surgery and radiation therapy, but no medical therapy for recurrent meningioma has proven effective. Methods: Pasireotide LAR is a long-acting somatostatin analog that may inhibit meningioma growth. This was a phase II trial in patients with histologically confirmed recurrent or progressive meningioma designed to evaluate whether pasireotide LAR prolongs progression-free survival at 6 months (PFS6). Patients were stratified by histology (atypical [World Health Organization grade 2] and malignant [grade 3] meningiomas in cohort A and benign [grade 3] in cohort B). Results: Eighteen patients were accrued in cohort A and 16 in cohort B. Cohort A had median age 59 years, median Karnofsky performance status 80, 17 (94%) had previous radiation therapy, and 11 (61%) showed high octreotide uptake. Cohort B had median age 52 years, median Karnofsky performance status 90, 11 (69%) had previous radiation therapy, and 12 (75%) showed high octreotide uptake. There were no radiographic responses to pasireotide LAR therapy in either cohort. Twelve patients (67%) in cohort A and 13 (81%) in cohort B achieved stable disease. In cohort A, PFS6 was 17%and median PFS 15 weeks (95%confidence interval: 8-20). In cohort B, PFS6 was 50% and median PFS 26 weeks (12-43). Treatment was well tolerated. Octreotide uptake and insulin-like growth factor-1 levels did not predict outcome. Expression of somatostatin receptor 3 predicted favorable PFS and overall survival. Conclusions: Pasireotide LAR has limited activity in recurrent meningiomas. The finding that somatostatin receptor 3 is associated with favorable outcomes warrants further investigation. Classification of evidence: This study provides Class IV evidence that in patients with recurrent or progressive meningioma, pasireotide LAR does not significantly increase the proportion of patients with PFS at 6 months. © 2014 American Academy of Neurology.