Cancer radiotherapy is often complicated by a spectrum of changes in the neighboring bone from mild osteopenia to osteoradionecrosis. We previously reported that parathyroid hormone (PTH, 1–34), an anabolic agent for osteoporosis, reversed bone structural...
Radiation Research
The influence of focal spot size, shape, emission profile and position on field coverage in a Gulmay D3300 Kilovoltage X-ray therapy unit
An important characteristic of kilovoltage therapy is the narrow penumbra obtainable with a well designed collimator system. A graphical illustration of applicator geometry is used to show that undesirable penumbral broadening and consequent reduction of field...
Focal radiation therapy combined with 4-1BB activation and CTLA-4 blockade yields long-term survival and a protective antigen-specific memory response in a murine glioma model.
BACKGROUND: Glioblastoma (GBM) is the most common malignant brain tumor in adults and is associated with a poor prognosis. Cytotoxic T lymphocyte antigen -4 (CTLA-4) blocking antibodies have demonstrated an ability to generate robust antitumor immune responses against...
Preclinical Models for Translational Research Should Maintain Pace With Modern Clinical Practice.
The technical evolution of radiation therapy for brain cancer has improved both the efficacy of individual radiation treatments and patient safety. The advent of computed tomography (CT)-based planning marked an important initial shift toward target-directed treatment (1). Treatment planning accuracy was further increased by fusing CT planning images with positron emission tomography (PET) and magnetic resonance imaging (MRI) scans (2, 3). Additionally, cone beam CT images acquired before each fraction were added to compensate for any deviations from the simulation CT (4).
Joshua T. Dilworth, Sarah A. Krueger, George D. Wilson, Brian Marples
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Radiosensitization of Pancreatic Cancer Cells In Vitro and In Vivo through Poly (ADP-ribose) Polymerase Inhibition with ABT-888
OBJECTIVES: To determine whether poly (ADP-ribose) polymerase-1/2 (PARP-1/2) inhibition enhances radiation-induced cytotoxicity of pancreatic adenocarcinoma in vitro and in vivo, and the mechanism by which this occurs. METHODS: Pancreatic carcinoma cells were treated...
Preclinical evaluation of the combination of mTOR and proteasome inhibitors with radiotherapy in malignant peripheral nerve sheath tumors
About one half of malignant peripheral nerve sheath tumors (MPNST) have Neurofibromin 1 (NF1) mutations. NF1 is a tumor suppressor gene essential for negative regulation of RAS signaling. Survival for MPNST patients is poor and we sought to identify an effective...
The Erlangen Dose Optimization trial for low-dose radiotherapy of benign painful elbow syndrome. Long-term results.
BACKGROUND AND PURPOSE: To evaluate the long-term efficacy of pain reduction by two dose fractionation schedules used for low-dose radiotherapy of painful elbow syndrome. PATIENTS AND METHODS: Between February 2006 and February 2010, 199 evaluable patients were...
Advances in kilovoltage x-ray beam dosimetry
This topical review provides an up-to-date overview of the theoretical and practical aspects of therapeutic kilovoltage x-ray beam dosimetry. Kilovoltage x-ray beams have the property that the maximum dose occurs very close to the surface and thus, they are...
Gold-Loaded Polymeric Micelles for Computed Tomography-Guided Radiation Therapy Treatment and Radiosensitization.
Gold nanoparticles (AuNPs) have generated interest as both imaging and therapeutic agents. AuNPs are attractive for imaging applications since they are nontoxic and provide nearly three times greater X-ray attenuation per unit weight than iodine. As therapeutic agents, AuNPs can sensitize tumor cells to ionizing radiation. To create a nanoplatform that could simultaneously exhibit long circulation times, achieve appreciable tumor accumulation, generate computed tomography (CT) image contrast, and serve as a radiosensitizer, gold-loaded polymeric micelles (GPMs) were prepared. Specifically, 1.9 nm AuNPs were encapsulated within the hydrophobic core of micelles formed with the amphiphilic diblock copolymer poly(ethylene glycol)-b-poly(ε-capralactone). GPMs were produced with low polydispersity and mean hydrodynamic diameters ranging from 25 to 150 nm. Following intravenous injection, GPMs provided blood pool contrast for up to 24 h and improved the delineation of tumor margins via CT. Thus, GPM-enhanced CT imaging was used to guide radiation therapy delivered via a small animal radiation research platform. In combination with the radiosensitizing capabilities of gold, tumor-bearing mice exhibited a 1.7-fold improvement in the median survival time, compared with mice receiving radiation alone. It is envisioned that translation of these capabilities to human cancer patients could guide and enhance the efficacy of radiation therapy.
Al Zaki A, Joh D, Cheng Z, De Barros AL, Kao G, Dorsey J, Tsourkas A.
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