Malignant glioma after ependymoma: an unusual secondary malignancy

Purpose : Secondary malignancies (SM) are a known long-­‐term problem in children surviving brain tumors. We report on two unusual cases of SM observed after treatment of ependymoma. Case reports : 1. The first case is a female survivor of a low-­‐grade ependymoma (Grade II). She had been treated at the age of 3 months with surgery and chemotherapy. A relapse of the primary tumor happened two years later, which was completely removed and treated with local radiotherapy to the posterior fossa. Fifteen years after the first cancer, she developed a pontine glioma near the location of the previous radiotherapy. 2. The second case is a femal survivor of an ependymoma (Grade III) which was removed and irradiated when she was 4 years old. The child developed a pontine glioma near the location of the previous radiotherapy ten years after the diagnosis of the first cancer. Further extension of the disease showed after biopsy PNET-­‐ like features. Both patients passed away. Discussion and Conclusion : Second malignant neoplasia is a rare phenomenon and this risk should not overshadow the great success in treating cancer of childhood. Among the studied risk factors, young age and radiotherapy are well established. The reported patients were followed annually to ensure their remission and both developed symptoms and an unusual unreported secondary cancer a few months after the annual monitoring that was considered as normal. This issue highlights the complexity of monitoring cancer survivors and raises the question of the best way for their long-­‐term follow-­‐up.

Stimulation of hematopoiesis in vivo by recombinant bacterial murine interleukin 3.

Mouse interleukin 3 (IL-3) cDNA was cloned into a plasmid construction, allowing the synthesis of very high quantities of IL-3 in Escherichia coli. The recombinant (r) IL-3, purified to homogeneity, was active in vitro on the proliferation and differentiation of various hematopoietic progenitor cells at 1 pM. To maintain detectable blood levels of IL-3, osmotic pumps containing rIL-3 or control solutions were placed under the skin of normal and irradiated C3H/HeJ and (BALB X B10) F1 mice. The effect of IL-3 on hematopoietic progenitor cell numbers in spleen and bone marrow was evaluated 3 and 7 days later by using an in vitro clonal assay. The results demonstrated the following: (i) Doses of IL-3 infused at the rate of 2.5-5 ng per g of body weight per hr were sufficient to increase the numbers of hematopoietic progenitors in normal mice by at least 2-fold within 3 days. (ii) In mice with progenitor cell levels depressed by sublethal irradiation, 7-day treatment with IL-3 resulted in a 10-fold increase to near normal levels. (iii) The erythroid and myeloid lineages appeared to be enhanced to the same extent. (iv) Enhancement of hematopoiesis occurred primarily in spleen, but hematopoietic foci were also evident in the liver; in contrast, total cell and progenitor cell numbers were decreased in the bone marrow.

Dummy run and conformity indices in the ongoing EORTC low-grade glioma trial 22033-26033: First evaluation of quality of radiotherapy planning.

PURPOSE: Early assessment of radiotherapy (RT) quality in the ongoing EORTC trial comparing primary temozolomide versus RT in low-grade gliomas. MATERIALS AND METHODS: RT plans provided for dummy cases were evaluated and compared against expert plans. We analysed: (1) tumour and organs-at-risk delineation, (2) geometric and dosimetric characteristics, (3) planning parameters, compliance with dose prescription and Dmax for OAR (4) indices: RTOG conformity index (CI), coverage factor (CF), tissue protection factor (PF); conformity number (CN = PF x CF); dose homogeneity in PTV (U). RESULTS: Forty-one RT plans were evaluated. Only two (5%) centres were requested to repeat CTV-PTV delineations. Three (7%) plans had a significant under-dosage and dose homogeneity in one deviated > 10%. Dose distribution was good with mean values of 1.5, 1, 0.68, and 0.68 (ideal values = 1) for CI, CF, PF, and CN, respectively. CI and CN strongly correlated with PF and they correlated with PTV. Planning with more beams seems to increase PTV(Dmin), improving CF. U correlated with PTV(Dmax). CONCLUSION: Preliminary results of the dummy run procedure indicate that most centres conformed to protocol requirements. To quantify plan quality we recommend systematic calculation of U and either CI or CN, both of which measure the amount of irradiated normal brain tissue.

Inducible gene and shRNA expression in resident hematopoietic stem cells in vivo.

Hematopoietic stem cells (HSC) are probably the best understood somatic stem cells and often serve as a paradigm for other stem cells. Nevertheless, most current techniques to genetically manipulate them in vivo are either constitutive and/or induced in settings of hematopoietic stress such as after irradiation. Here, we present a conditional expression system that allows for externally controllable transgenesis and knockdown in resident HSCs, based on a lentiviral vector containing a tet-O sequence and a transgenic mouse line expressing a doxycyclin-regulated tTR-KRAB repressor protein. HSCs harvested from tTR-KRAB mice are transduced with the lentiviral vector containing a cDNA (i.e., Green Fluorescent Protein (GFP)) and/or shRNA (i.e., p53) of interest and then transplanted into lethally irradiated recipients. While the vector is effectively repressed by tTR-KRAB during homing and engraftment, robust GFP/shp53 expression is induced on doxycyclin treatment in HSCs and their progeny. Doxycylin-controllable transcription is maintained on serial transplantation, indicating that repopulating HSCs are stably modified by this approach. In summary, this easy to implement conditional system provides inducible and reversible overexpression or knock down of genes in resident HSCs in vivo using a drug devoid of toxic or activating effects.

Cytotoxic T cells deficient in both functional fas ligand and perforin show residual cytolytic activity yet lose their capacity to induce lethal acute graft-versus-host disease.

Graft-versus-host disease (GVHD) is the main complication after allogeneic bone marrow transplantation. Although the tissue damage and subsequent patient mortality are clearly dependent on T lymphocytes present in the grafted inoculum, the lethal effector molecules are unknown. Here, we show that acute lethal GVHD, induced by the transfer of splenocytes from C57BL/6 mice into sensitive BALB/c recipients, is dependent on both perforin and Fas ligand (FasL)-mediated lytic pathways. When spleen cells from mutant mice lacking both effector molecules were transferred to sublethally irradiated allogeneic recipients, mice survived. Delayed mortality was observed with grafted cells deficient in only one lytic mediator. In contrast, protection from lethal acute GVHD in resistant mice was exclusively perforin dependent. Perforin-FasL-deficient T cells failed to lyse most target cells in vitro. However, they still efficiently killed tumor necrosis factor alpha-sensitive fibroblasts, demonstrating that cytotoxic T cells possess a third lytic pathway.

Photosensitizing effects of m-tetrahydroxyphenylchlorin on human tumor xenografts: correlation with sensitizer uptake, tumor doubling time and tumor histology.

The photodynamic effects of m-tetrahydroxyphenylchlorin (mTHPC) were assessed on human malignant mesothelioma, squamous cell carcinoma and adenocarcinoma xenografts grown in nude mice and were correlated with mTHPC uptake, histology and doubling time of the tumors. Non-thermal laser light was delivered to the tumor as surface radiation 4 days after intraperitoneal administration of 0.1 and 0.3 mg mTHPC/kg body weight, respectively. The extent of tumor necrosis was measured by histomorphometry. The mTHPC concentration in non-irradiated tumors was assessed by high-performance liquid chromatography (HPLC). The tumors were graded according to their doubling time and their vascular architecture as assessed by histology. The 0.1 mg/kg dose of mTHPC resulted in an equal uptake for all 3 tumor types but revealed a larger extent of photosensitized necrosis for adenocarcinoma, which displayed a delicate tumor stroma with numerous small capillary vessels, than for mesothelioma and squamous cell carcinoma, which were both poor in stroma and vessels. The 0.3 mg/kg dose of mTHPC resulted in a 2-fold higher tumor uptake for all 3 tumor types and in a larger extent of necrosis for mesothelioma and squamous cell carcinoma, but not for adenocarcinoma xenografts, compared with the lower drug dose. Our results demonstrate that different tumor xenografts respond differently to mTHPC-PDT for a given drug-light condition. In this setting, the photosensitizing effect was more closely related to the vascular architecture of the tumors than to the sensitizer uptake and doubling time of the different tumors

Transpalpebral proton beam radiotherapy of choroidal melanoma.

BACKGROUND: Collateral damage to upper eyelid margin during proton beam radiotherapy (PBR) for choroidal melanoma may cause squamous metaplasia of the tarsal conjunctiva with keratinisation, corneal irritation, discomfort and, rarely, corneal perforation. We evaluated transpalpebral PBR as a means of avoiding collateral damage to the upper eyelid margin without increasing the risk of failure of local tumour control. METHODS: Retrospective study of consecutive patients who underwent PBR for choroidal melanoma between 1992 and 2007 at the Royal Liverpool University Hospital and the Douglas Cyclotron at Clatterbridge Cancer Centre, UK. RESULTS: Sixty-three patients were included in this study. Mean basal tumour diameter and tumour thickness were 11.8 mm and 3.6 mm, respectively. PBR mean beam range and modulation were 26.5 mm and 16.9 mm respectively. The eyelid margin was included in the radiation field in 15 (24%) eyes. The median follow-up was 2.5 years. Local tumour recurrence developed in 2 (3.2%) patients. In these two cases that developed tumour recurrence the transpalpebral treatment did not involve the eyelid margin. Six (9.5%) patients died of metastatic disease. No eyelid or ocular surface problems developed in any of the 48 patients who were treated without eyelid rim involvement, while 7 of the 15 patients with unavoidable irradiation of the eyelid rim developed some degree of madarosis. These seven patients all received more than 26.55 proton Gy to the eyelid margin. Symptoms, such as grittiness occurred in 12% of 48 patients without eyelid margin irradiation as compared with 53% of 15 patients whose lid margin was irradiated. CONCLUSIONS: Transpalpebral PBR of choroidal melanoma avoids eyelid and ocular surface complications without increasing failure of local tumour control.

Functional analysis of different haematopoietic stem cell subsets

RÉSUMÉ : Elucider les bases moléculaires et cellulaires du fonctionnement des cellules souches s'avère crucial dans la compréhension de l'organisation cellulaire au sein des tissus et des organes ainsi que pour le développement de nouvelles stratégies thérapeutiques en médecine régénérative et en oncologie. Les cellules souches adultes les mieux connues sont celles responsables de l'hématopoïèse, les cellules souches hématopoïétiques (CSH). Durant ces dernières années, la recherche a porté une attention particulière à l'isolation prospective de CSH dérivées de la moelle osseuse de souris en utilisant des marqueurs de surface cellulaire ainsi que des propriétés fonctionnelles alléguées. Par la suite, la capacité fonctionnelle des CSH a été vérifiée classiquement par leur transplantation intraveineuse dans des souris réceptrices conditionnées et par l'analyse de leur aptitude à reconstituer le système hématopoïétique à long terme. Des études récentes suggèrent que la transplantation des cellules directement dans la moelle osseuse pourrait non seulement aboutir à une prise de greffe plus rapide et plus efficace, mais pourrait même aider à l'identification de cellules qui ont certes des propriétés intrinsèques de CSH, mais qui n'ont pas la capacité de trouver leur niche au sein de la moelle osseuse et ont donc échoué dans les analyses classiques de reconstitution. Dans cette étude, nous comparons à deux niveaux la fonction de différents sous-groupes de cellules souches de la moelle osseuse, définis par leur phénotype de surface cellulaire. Premièrement, nous étudions leur capacité à reconstituer des souris létalement irradiées après injection soit intraveineuse soit intrafémorale. Deuxièmement, par analyse cytométrique de flux à 8 couleurs, nous comparons leur activité relative de « side population » (SP) par exclusion du colorant fluorescent Hoechst 33342. Nos résultats préliminaires renforcent en effet l'idée que la transplantation intrafémorale aboutit à une greffe plus rapide et plus efficace. Par contre, en utilisant cette approche, nous n'arrivons pas à identifier des cellules capables de prendre greffe spécifiquement quand elles sont injectées en intrafémorale. Finalement, bien qu'une confirmation in vivo soit encore nécessaire, nous suggérons sur la base de nos analyses cytométriques de flux, que les cellules SP Sca1t~és éie~~ CD48t~és bas sont très enrichies en CSH. Ceci permettrait l'isolation ex vivo de CSH de la moelle osseuse de souris par une stratégie à la fois nouvelle et simple. SUMMARY : Elucidating the molecular and cellular bases of stem cell function is crucial for the understanding of cellular organisation within tissues and organs as well as for the development of new therapeutic strategies in regenerative medicine and oncology. The best-known adult stem cells are those responsible for haematopoiesis, the haematopoietic stem cells (HSCs). In recent years, much effort has been put into the prospective isolation of mouse bone marrow (BM)-derived HSCs using cell-surface markers and alleged functional properties. Upon isolation, the functional capacity of putative HSCs has been classically assessed by intravenous transplantation into conditioned recipient mice and analysis of their ability to reconstitute the haematopoietic system at long-term. It has recently been suggested that transplanting the cells directly into the BM might not only result in more rapid and more effective engraftment, but even help to identify cells that have intrinsic HSC properties but lack the ability to home to their BM niche and have thus failed to succeed in classical reconstitution assays. In this study, we compare the function of different BM cell subsets, as defined by their cell surface phenotype, on two levels. Firstly, we assess their ability to reconstitute lethally irradiated mice, when injected either intravenously or intrafemorally. Secondly, using 8-colour flow cytometric analysis, we compare their relative side population (SP) activity by exclusion of the fluorescent dye Hoechst 33342. Our preliminary results indeed reinforce the idea that intrafemoral transplantation results in faster and more effective engraftment, however, using this approach, we are unable to identify cells that are capable of engrafting specifically when injected intrafemorally. Finally, although in vivo confirmation is still required, we propose, based on the results of our flow cytometric analyses, that SP Scat Very h'9h CD48Very'°W cells should be highly enriched for HSCs. This would allow for a simple new strategy for the isolation of mouse BM HSCs ex vivo.

Target Molecular Size and Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis Analysis of the ATP-and Pyrophosphate-Dependent Proton Pumps from Maize Root Tonoplast.

Tonoplast-enriched membranes were prepared from maize (Zea mays L. cv LG 11) primary roots, using sucrose nonlinear gradients. The functional molecular size of the tonoplast ATP-and PPi-dependent proton pumps were analyzed by radiation inactivation. Glucose-6-phosphate dehydrogenase (G6PDH) was added as an internal standard. Frozen samples (-196 degrees C) of the membranes were irradiated with (60)Co for different periods of time. After thawing the samples, the activities of G6PDH, ATPase, and PPase were tested. By applying target theory, the functional sizes of the ATPase and PPase in situ were found to be around 540 and 160 kilodaltons, respectively. The two activities were solubilized and separated by gel filtration chromatography. The different polypeptides copurifying with the two pumps were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Two bands (around 59 and 65 kilodaltons) were associated with the ATPase activity, whereas a double band (around 40 kilodaltons) was recovered with the PPase activity.

Dose reconstruction in the context of tomotherapy

In vivo dosimetry is a way to verify the radiation dose delivered to the patient in measuring the dose generally during the first fraction of the treatment. It is the only dose delivery control based on a measurement performed during the treatment. In today's radiotherapy practice, the dose delivered to the patient is planned using 3D dose calculation algorithms and volumetric images representing the patient. Due to the high accuracy and precision necessary in radiation treatments, national and international organisations like ICRU and AAPM recommend the use of in vivo dosimetry. It is also mandatory in some countries like France. Various in vivo dosimetry methods have been developed during the past years. These methods are point-, line-, plane- or 3D dose controls. A 3D in vivo dosimetry provides the most information about the dose delivered to the patient, with respect to ID and 2D methods. However, to our knowledge, it is generally not routinely applied to patient treatments yet. The aim of this PhD thesis was to determine whether it is possible to reconstruct the 3D delivered dose using transmitted beam measurements in the context of narrow beams. An iterative dose reconstruction method has been described and implemented. The iterative algorithm includes a simple 3D dose calculation algorithm based on the convolution/superposition principle. The methodology was applied to narrow beams produced by a conventional 6 MV linac. The transmitted dose was measured using an array of ion chambers, as to simulate the linear nature of a tomotherapy detector. We showed that the iterative algorithm converges quickly and reconstructs the dose within a good agreement (at least 3% / 3 mm locally), which is inside the 5% recommended by the ICRU. Moreover it was demonstrated on phantom measurements that the proposed method allows us detecting some set-up errors and interfraction geometry modifications. We also have discussed the limitations of the 3D dose reconstruction for dose delivery error detection. Afterwards, stability tests of the tomotherapy MVCT built-in onboard detector was performed in order to evaluate if such a detector is suitable for 3D in-vivo dosimetry. The detector showed stability on short and long terms comparable to other imaging devices as the EPIDs, also used for in vivo dosimetry. Subsequently, a methodology for the dose reconstruction using the tomotherapy MVCT detector is proposed in the context of static irradiations. This manuscript is composed of two articles and a script providing further information related to this work. In the latter, the first chapter introduces the state-of-the-art of in vivo dosimetry and adaptive radiotherapy, and explains why we are interested in performing 3D dose reconstructions. In chapter 2 a dose calculation algorithm implemented for this work is reviewed with a detailed description of the physical parameters needed for calculating 3D absorbed dose distributions. The tomotherapy MVCT detector used for transit measurements and its characteristics are described in chapter 3. Chapter 4 contains a first article entitled '3D dose reconstruction for narrow beams using ion chamber array measurements', which describes the dose reconstruction method and presents tests of the methodology on phantoms irradiated with 6 MV narrow photon beams. Chapter 5 contains a second article 'Stability of the Helical TomoTherapy HiArt II detector for treatment beam irradiations. A dose reconstruction process specific to the use of the tomotherapy MVCT detector is presented in chapter 6. A discussion and perspectives of the PhD thesis are presented in chapter 7, followed by a conclusion in chapter 8. The tomotherapy treatment device is described in appendix 1 and an overview of 3D conformai- and intensity modulated radiotherapy is presented in appendix 2. - La dosimétrie in vivo est une technique utilisée pour vérifier la dose délivrée au patient en faisant une mesure, généralement pendant la première séance du traitement. Il s'agit de la seule technique de contrôle de la dose délivrée basée sur une mesure réalisée durant l'irradiation du patient. La dose au patient est calculée au moyen d'algorithmes 3D utilisant des images volumétriques du patient. En raison de la haute précision nécessaire lors des traitements de radiothérapie, des organismes nationaux et internationaux tels que l'ICRU et l'AAPM recommandent l'utilisation de la dosimétrie in vivo, qui est devenue obligatoire dans certains pays dont la France. Diverses méthodes de dosimétrie in vivo existent. Elles peuvent être classées en dosimétrie ponctuelle, planaire ou tridimensionnelle. La dosimétrie 3D est celle qui fournit le plus d'information sur la dose délivrée. Cependant, à notre connaissance, elle n'est généralement pas appliquée dans la routine clinique. Le but de cette recherche était de déterminer s'il est possible de reconstruire la dose 3D délivrée en se basant sur des mesures de la dose transmise, dans le contexte des faisceaux étroits. Une méthode itérative de reconstruction de la dose a été décrite et implémentée. L'algorithme itératif contient un algorithme simple basé sur le principe de convolution/superposition pour le calcul de la dose. La dose transmise a été mesurée à l'aide d'une série de chambres à ionisations alignées afin de simuler la nature linéaire du détecteur de la tomothérapie. Nous avons montré que l'algorithme itératif converge rapidement et qu'il permet de reconstruire la dose délivrée avec une bonne précision (au moins 3 % localement / 3 mm). De plus, nous avons démontré que cette méthode permet de détecter certaines erreurs de positionnement du patient, ainsi que des modifications géométriques qui peuvent subvenir entre les séances de traitement. Nous avons discuté les limites de cette méthode pour la détection de certaines erreurs d'irradiation. Par la suite, des tests de stabilité du détecteur MVCT intégré à la tomothérapie ont été effectués, dans le but de déterminer si ce dernier peut être utilisé pour la dosimétrie in vivo. Ce détecteur a démontré une stabilité à court et à long terme comparable à d'autres détecteurs tels que les EPIDs également utilisés pour l'imagerie et la dosimétrie in vivo. Pour finir, une adaptation de la méthode de reconstruction de la dose a été proposée afin de pouvoir l'implémenter sur une installation de tomothérapie. Ce manuscrit est composé de deux articles et d'un script contenant des informations supplémentaires sur ce travail. Dans ce dernier, le premier chapitre introduit l'état de l'art de la dosimétrie in vivo et de la radiothérapie adaptative, et explique pourquoi nous nous intéressons à la reconstruction 3D de la dose délivrée. Dans le chapitre 2, l'algorithme 3D de calcul de dose implémenté pour ce travail est décrit, ainsi que les paramètres physiques principaux nécessaires pour le calcul de dose. Les caractéristiques du détecteur MVCT de la tomothérapie utilisé pour les mesures de transit sont décrites dans le chapitre 3. Le chapitre 4 contient un premier article intitulé '3D dose reconstruction for narrow beams using ion chamber array measurements', qui décrit la méthode de reconstruction et présente des tests de la méthodologie sur des fantômes irradiés avec des faisceaux étroits. Le chapitre 5 contient un second article intitulé 'Stability of the Helical TomoTherapy HiArt II detector for treatment beam irradiations'. Un procédé de reconstruction de la dose spécifique pour l'utilisation du détecteur MVCT de la tomothérapie est présenté au chapitre 6. Une discussion et les perspectives de la thèse de doctorat sont présentées au chapitre 7, suivies par une conclusion au chapitre 8. Le concept de la tomothérapie est exposé dans l'annexe 1. Pour finir, la radiothérapie «informationnelle 3D et la radiothérapie par modulation d'intensité sont présentées dans l'annexe 2.

Improvement of saliva production in ENT cancer patients treated by IMRT

Intensity modulated radiotherapy (IMRT) is a conformal radiotherapy that produces concave and irregular target volume dose distributions. IMRT has a potential to reduce the volume of healthy tissue irradiated to a high dose, but this often at the price of an increased volume of normal tissue irradiated to a low dose. Clinical benefits of IMRT are expected to be most pronounced at the body sites where sensitive normal tissues surround or are located next to a target with a complex 3D shape. The irradiation doses needed for tumor control are often markedly higher than the tolerance of the radiation sensitive structures such as the spinal cord, the optic nerves, the eyes, or the salivary glands in the treatment of head and neck cancer. Parotid gland salivary flow is markedly reduced following a cumulative dose of 30 50 Gy given with conventional fractionation and xerostomia may be prevented in most patients using a conformal parotid-sparing radiotherapy technique. However, in cohort studies where IMRT was compared with conventional and conformal radiotherapy techniques in the treatment of laryngeal or oropharyngeal carcinoma, the dosimetric advantage of IMRT translated into a reduction of late salivary toxicity with no apparent adverse impact on the tumor control. IMRT might reduce the radiation dose to the major salivary glands and the risk of permanent xerostomia without compromizing the likelihood for cure. Alternatively, IMRT might allow the target dose escalation at a given level of normal tissue damage. We describe here the clinical results on postirradiation salivary gland function in head and neck cancer patients treated with IMRT, and the technical aspects of IMRT applied. The results suggest that the major salivary gland function can be maintained with IMRT without a need to compromise the clinical target volume dose, or the locoregional control.

Therapeutic PD-1 pathway blockade augments with other modalities of immunotherapy T-cell function to prevent immune decline in ovarian cancer.

The tumor microenvironment mediates induction of the immunosuppressive programmed cell death-1 (PD-1) pathway, and targeted interventions against this pathway can help restore antitumor immunity. To gain insight into these responses, we studied the interaction between PD-1 expressed on T cells and its ligands (PD-1:PD-L1, PD-1:PD-L2, and PD-L1:B7.1), expressed on other cells in the tumor microenvironment, using a syngeneic orthotopic mouse model of epithelial ovarian cancer (ID8). Exhaustion of tumor-infiltrating lymphocytes (TIL) correlated with expression of PD-1 ligands by tumor cells and tumor-derived myeloid cells, including tumor-associated macrophages (TAM), dendritic cells, and myeloid-derived suppressor cells (MDSC). When combined with GVAX or FVAX vaccination (consisting of irradiated ID8 cells expressing granulocyte macrophage colony-stimulating factor or FLT3 ligand) and costimulation by agonistic α-4-1BB or TLR 9 ligand, antibody-mediated blockade of PD-1 or PD-L1 triggered rejection of ID8 tumors in 75% of tumor-bearing mice. This therapeutic effect was associated with increased proliferation and function of tumor antigen-specific effector CD8(+) T cells, inhibition of suppressive regulatory T cells (Treg) and MDSC, upregulation of effector T-cell signaling molecules, and generation of T memory precursor cells. Overall, PD-1/PD-L1 blockade enhanced the amplitude of tumor immunity by reprogramming suppressive and stimulatory signals that yielded more powerful cancer control.

European French-speaking study from the GEMO group on bone metastases management: a special focus on external beam radiotherapy practice survey.

This study seeks to perform a survey of patterns of practice among the different physicians involved in the bone metastases management, with special focus on external beam radiotherapy (EBRT).A questionnaire about bone metastases based on clinical cases and supplemented with general questions, including medical therapies, EBRT and metabolic radiotherapy strategies, surgery, and supportive care approaches, was sent to 4,706 French-speaking physicians in Belgium, France, Luxemburg, and Switzerland.Overall, 644 questionnaires were analyzed. Twenty-eight percent concerned the radiotherapy approach and were judged adequate to respond to the part dedicated to EBRT. Sixty-nine percent of physicians used a total dose irradiation of 30 Gy delivered in ten fractions. A large majority (75%) used two opposed fields prescribed at mid-depth (30%), or with non-equally weighted fields (45%). Seventy percent irradiated also above and below the concerned vertebra. A dosimetry planning treatment was done in 85% and high-energy megavoltage photons were used in 42%. Moreover, 54% physicians used short course radiotherapy in routine.Radiotherapy remains the mainstay of treatment of bone metastases, but there is substantial heterogeneity in clinical practice. Guidelines and treatment protocols are required to improve the treatment quality.

Role of mTOR, Bad, and Survivin in RasGAP Fragment N-Mediated Cell Protection.

Partial cleavage of p120 RasGAP by caspase-3 in stressed cells generates an N-terminal fragment, called fragment N, which activates an anti-apoptotic Akt-dependent survival response. Akt regulates several effectors but which of these mediate fragment N-dependent cell protection has not been defined yet. Here we have investigated the role of mTORC1, Bad, and survivin in the capacity of fragment N to protect cells from apoptosis. Neither rapamycin, an inhibitor of mTORC1, nor silencing of raptor, a subunit of the mTORC1 complex, altered the ability of fragment N from inhibiting cisplatin- and Fas ligand-induced death. Cells lacking Bad, despite displaying a stronger resistance to apoptosis, were still protected by fragment N against cisplatin-induced death. Fragment N was also able to protect cells from Fas ligand-induced death in conditions where Bad plays no role in apoptosis regulation. Fragment N expression in cells did neither modulate survivin mRNA nor its protein expression. Moreover, the expression of cytoplasmic survivin, known to exert anti-apoptotic actions in cells, still occurred in UV-B-irradiated epidermis of mouse expressing a caspase-3-resistant RasGAP mutant that cannot produce fragment N. Additionally, survivin function in cell cycle progression was not affected by fragment N. These results indicate that, taken individually, mTOR, Bad, or Survivin are not required for fragment N to protect cells from cell death. We conclude that downstream targets of Akt other than mTORC1, Bad, or survivin mediate fragment N-induced protection or that several Akt effectors can compensate for each other to induce the pro-survival fragment N-dependent response.

Biogeographic analysis of Crocidiinae (Diptera, Bombyliidae): finding congruence among morphological, molecular, fossil and paleogeographical data

Biogeographic studies dealing with Bombyliidae are rare in the literature and no information is available on its origin and early diversification. In this study, we found evidence from molecular phylogeny and from fossil record supporting a Middle Jurassic origin of the Bombylioidea, taken as a starting point to discuss the biogeography and diversification of Crocidiinae. Based on a previously published phylogenetic hypothesis, we performed a Brooks Parsimony Analysis (BPA) to discuss the biogeographical history of Crocidiinae lineages. This subfamily is mostly distributed over arid areas of the early components of the Gondwanaland: Chile and southern Africa, but also in southwestern Palaearctic and southwestern Nearctic. The vicariant events affecting the Crocidiinae biogeography at the generic level seems to be related to the sequential separation of a Laurasian clade from a Gondwanan clade followed by the splitting of the latter into smaller components. This also leads to a hypothesis of origin of the Crocidiinae in the Middle Jurassic, the same period in which other bombyliid lineages are supposed to have arisen and irradiated.