The mammalian target of rapamycin (mTOR) modulates key signaling pathways that promote uncontrolled proliferation of glioblastoma multiforme (GBM). Because rapid tumor proliferation may contribute to the clinical radioresistance of GBM tumors, the combination of rapamycin, a selective mTOR inhibitor, and radiation was studied in vitro and in vivo in a GBM model. In monolayer cultures of U87 and...

Experiments were performed to study the action of fractionated irradiation of mice heads with -rays and protons on their peripheral blood parameters and behavior by the “Open Field” test. Mice were irradiated in two variants of fractionated irradiation: (1) traditional fractionation (in radiation therapy): 2 Gy once a day, 5 times a week, the total radiation dose 20 Gy; (2) extreme hypofractio...

BACKGROUND AND PURPOSE Vascular endothelial growth factor (VEGF), a specific pro-angiogenic factor is proposed to be involved in cancer progression and resistance to radiation therapy by promoting angiogenesis and by protecting endothelial cells from radiation induced apoptosis. The aim of this study, was first to assess the influence of ionizing radiation on plasma VEGF concentration in sponta...

Currently, the contribution of cellular apoptotic sensitivity to tumor response after radiation therapy remains controversial. To address this issue, the survival of Rat-1 fibroblasts containing a 4-hydroxytamoxifen-regulated c-Myc allele, c-MycER (T. D. Littlewood et al., Nucleic Acids Res., 23: 1686-1690, 1995), after single and fractionated doses of radiation was investigated. This model sys...

BACKGROUND Despite the advancement of microsurgical and endoscopic techniques, some nonfunctioning pituitary adenomas (NFPAs) can be difficult to cure. Tumor recurrence or incomplete resection may occur in some patients with NFPAs, and management strategies for these NFPAs remain unclear. OBJECTIVE To review the existing literature as it pertains to the management of postsurgical residual or ...

PurposeSpatially fractionated radiation therapy (SFRT) is increasingly used for bulky advanced tumors, but specifics of clinical SFRT practice remain elusive. This study aimed to determine patterns GRID and Lattice (LRT) based SFRT.Materials MethodsA survey was designed identify oncologists’ patient selection SFRT, dosing/planning, dosimetric parameter use, platforms/techniques, combinations wi...

Purpose Limited data exist on fractionated stereotactic radiation therapy (FSRT) for brain metastases. We sought to evaluate the safety and efficacy of FSRT and further define its role in brain metastasis management. Methods and materials A total of 72 patients were treated with linear accelerator-based FSRT to 182 previously untreated, intact brain metastases. Targets received 25 or 30 Gy in...

This report describes radiation-induced osteosarcomas in two groups of dogs. One group was given radiation therapy for spontaneous tumors and the second group of normal adult beagle dogs was given experimental intraoperative radiation therapy. Secondary tumors developed between 1.7 to 5 years after irradiation. Three of 87 spontaneous tumor-bearing dogs or 3.4% of dogs treated for soft tissue s...