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Glioblastoma multiforme (GBM) is the most common and malignant primary brain tumour, with very poor prognosis. The high recurrence rate and failure of conventional treatments are expected to be related to the presence of radio-resistant cancer stem cells (CSCs) inside the tumour mass. CSCs can both self-renew and differentiate into the heterogeneous lineages of cancer cells. Recent evidence showed a higher effectiveness of C-ions and protons in inactivating CSCs, suggesting a potential advantage of Hadrontherapy compared with conventional radiotherapy for GBM treatment. To investigate the mechanisms involved in the molecular and cellular responses of CSCs to ionising radiations, two GBM stem cell (GSC) lines, named lines 1 and 83, which were derived from patients with different clinical outcomes and having different metabolic profiles (as shown by NMR spectroscopy), were irradiated with 137Cs photons and with protons or C-ions of 62 MeV u-1 in the dose range of 5-40 Gy. The biological effects investigated were: cell death, cell cycle progression, and DNA damage induction and repair. Preliminary results show a different response to ionising radiation between the two GSC lines for the different end points investigated. Further experiments are in progress to consolidate the data and to get more insights on the influence of radiation quality. © The Author 2015.

A high energy resolution, high dispersive power Thomson Parabola Spectrometer has been developed at INFN-LNS in order to characterize laser-driven beams up to 30- 40 MeV for protons. This device has parallel electric and magnetic field to deflect particles of a certain charge-to-mass ratio onto parabolic traces on the detection plane. Calibration of the deflection sector is crucial for data analysis, namely energy determination of analysed beam, and to evaluate the effective energy limit and resolution. This work reports the study of monochromatic proton beams delivered by the TANDEM accelerator at LNS (Catania) in the energy range between 6 and 12.5 MeV analysed with our spectrometer which allows a precise characterization of the electric and magnetic deflections. Also the energy and the Q/A resolutions and the energy limits have been evaluated proposing a mathematical model that can be used for data analysis, for the experimental set up and for the device scalability for higher energy.

Laser accelerated proton beams represent nowadays an attractive alternative to the conventional ones and they have been proposed in different research fields. In particular, the interest has been focused in the possibility of replacing conventional accelerating machines with laser-based accelerators in order to develop a new concept of hadrontherapy facilities, which could result more compact and less expensive. With this background the ELIMED (ELIMED: ELI-Beamlines MEDical applications) research project has been launched by LNS-INFN researchers (Laboratori Nazionali del Sud-Istituto Nazionale di Fisica Nucleare, Catania, IT) and ASCR-FZU researchers (Academy of Sciences of the Czech Republic-Fyzikalni ustar, Prague, Cz), within the pan-European ELI-Beamlines facility framework. Its main purposes are the demonstration of future applications in hadrontherapy of optically accelerated protons and the realization of a laser-accelerated ion transport beamline for multidisciplinary applications. Several challenges, starting from laser-target interaction and beam transport development, up to dosimetric and radiobiological issues, need to be overcome in order to reach the final goals. The design and the realization of a preliminary beam handling and dosimetric system and of an advanced spectrometer for high energy (multi-MeV) laser-accelerated ion beams will be shortly presented in this work.

The design of a detector for tracking charged particles is presented together with the characterization techniques developed to extract the main design specifications. The goals for the final detector are to achieve real-time imaging performances, a large detection area, and a high spatial resolution, particularly suitable for medical imaging applications. This paper describes the prototype of the tracker plane, which has a 20 × 20 cm2sensitive area consisting of two crossed ribbons of 500 μm square scintillating fibers. The information about the hit position extracted real-time tracker in an innovative way, using a reduced number of the read-out channels to obtain a very large detection area but with moderate costs and complexity. The performances of the tracker have been investigated usingβsources, cosmic rays, and a 62 MeV proton beam.

Proton Computed Tomography (pCT) is a medical imaging technique based on the use of proton beams with energies above 200 MeV to directly measure stopping power distributions inside the tissue volume. Prima (PRoton IMAging) is an Italian collaboration working on the development of a pCT scanner based on a tracker and a calorimeter to measure single protons trajectory and residual energy. The tracker is composed of four planes of silicon microstrip detectors to measure proton entry and exit positions and angles. Residual energy is measured by a calorimeter composed of YAG:Ce scintillating crystals. A first prototype of pCT scanner, with an active area of about 5×5 cm2, has been constructed and characterized with 60 MeV protons at the INFN Laboratori Nazionali del Sud, Catania (Italy) and with 180 MeV protons at Svedberg Laboratory, Uppsala (Sweden). A new pre-clinical prototype with an extended active area up to 20×5 cm2, real time data acquisition and a data rate up to 1 MHz is under development. A description of the two prototypes will be presented together with first results concerning tomographic image reconstruction.

The PRIMA (Proton IMAging) experiment is aimed at developing a proton Computed Tomography (pCT) prototype based on tracking single protons. Approaches to the pCT consist in the use of silicon microstrip detectors to measure the position and direction of individual protons before and after they traverse the phantom, in view to reconstruct the trajectory of each proton, and a calorimeter for measuring particle residual energy. A small prototype was tested, under 62 MeV proton beam at Laboratory Nazionali del Sud, (Catania Italy) and under 180 MeV proton beam at Svedberg Laboratories, Uppsala Universitet, (Uppsala Sweden). Several experiments concerning proton imaging, tomography and radiography, were carried out during these beam tests. Radiographies have been reconstructed with different methods: results show the good performances of the device, with spatial resolution fulfilling the stringent requirements of a pCT device.

In this paper we describe a novel system for the tracking of charged particles, designed to achieve real-time imaging, large detection areas and high spatial resolution especially suitable for use in medical diagnostic. A prototype of this tracker, having a 20 × 20 cm2 sensitive area, consisting of two crossed ribbons of 500 11m square scintillating fibers has been developed. The track position information is extracted real time in an innovative way, using a reduced number of read-out channels to obtain very large detection area with enough moderate costs and complexity. The performances of the tracker have been investigated using both β sources and cosmic rays and finally with a 62 MeV proton beam.

Proton Computed Tomography (pCT) is an imaging method under investigation with the aim to improve the accuracy of treatment planning and patient positioning in hadron therapy. A pCT system should be capable to measure tissue electron density with an accuracy better than 1% and with a spatial resolution better than 1mm. A first apparatus based on a silicon tracker and a YAG:Ce crystal calorimeter, with a 5×5 cm2 active area, has been already developed by the authors in the framework of the PRIMA (Proton Imaging) collaboration and tested with proton beams with promising results. A second prototype with larger area (5×20 cm2) and improved data acquisition system is being designed. The details about this new prototype will be presented in this work.