Radiotherapy is frequently used as treatment for oral cancer either alone or in combination with surgery. Reaction of tumor tissue to radiotherapy often shows marked inter-individual variability making it difficult to assess and predict the treatment outcome for individual patients. Recently attention has been drawn towards the role of radiation induced nuclear changes to assess radiosensitivit...

Metastasis is the process by which cells from a primary tumor disperse and form new tumors at distant anatomical locations. The treatment and prevention of metastatic cancer remains an extremely challenging problem. This work introduces a novel biologically motivated objective function to the radiation optimization community that takes into account metastatic risk instead of the status of the p...

BACKGROUND This study was performed to evaluate the efficacy and safety of fractionated Gamma Knife radiosurgery (GKRS) for perioptic lesions. METHODS Thirty-eight patients with perioptic tumors were treated at our institute from May 2004 to December 2008. All patients had a lesion in close contact with the optic apparatus. Twenty-four of these patients had undergone surgical resection before...

PURPOSE To investigate the radiosensitizing potential of temozolomide (TMZ) for human glioblastoma multiforme (GBM) cell lines using single-dose and fractionated gamma-irradiation. METHODS AND MATERIALS Three genetically characterized human GBM cell lines (AMC-3046, VU-109, and VU-122) were exposed to various single (0-6 Gy) and daily fractionated doses (2 Gy per fraction) of gamma-irradiatio...

To limit toxicity to normal tissues adjacent to the target tumour volume, radiotherapy is delivered using fractionated regimes whereby the total prescribed dose is given as a series of sequential smaller doses separated by specific time intervals. The impact of fractionation on out-of-field survival and DNA damage responses was determined in AGO-1522 primary human fibroblasts and MCF-7 breast t...

We have previously reported that the use of the polymer bis(p-carboxyphenoxy)propane-sebacic acid (20:80) for intratumoral delivery of cis-platinum in a mouse tumor model (RIF-1) potentiated the effects of acute and fractionated radiation. This mode of drug delivery seems particularly applicable to the administration of radiosensitizing drugs because an optimum concentration of radiosensitizer ...

Fractionated radiotherapy (RT) is widely used in cancer therapy for its advantages in the preservation of normal tissues. However, repopulation of surviving tumor cells during fractionated RT limits the efficacy of RT. In fact, repopulating tumors often acquire radioresistance and this is the major cause of failure of RT. We have recently demonstrated that human tumor cells acquire radioresista...

BACKGROUND In the quest of a curative radiotherapy treatment for gliomas new delivery modes are being explored. At the Biomedical Beamline of the European Synchrotron Radiation Facility (ESRF), a new spatially-fractionated technique, called Minibeam Radiation Therapy (MBRT) is under development. The aim of this work is to compare the effectiveness of MBRT and broad-beam (BB) synchrotron radiati...

Growing tumors are hypoxic and respond to microenvironmental stress through increased expression of the hypoxia inducible factor-1alpha (HIF-1alpha) transcription factor, resulting in an adaptive switch to glycolytic metabolism, angiogenic signaling, survival, and metastasis. HIF-1alpha expression is associated with tumor resistance to cytotoxic therapy and inferior patient outcomes. Pancreatic...

The potential of an oxygen-carrying perfluorochemical emulsion (PFCE) to enhance radiation damage in Lewis lung tumor growing in C57BL/6J X DBA/2J F1 mice was examined. PFCE and 95% O2:5% CO2 (carbogen) breathing caused a significant enhancement of single-fraction radiation damage measured by the growth delay assay. The dose-response effect of PFCE was very broad; doses as small as 0.5 ml/mouse...