Stereotactic radiotherapy for large solitary brain metastases

PURPOSE

To assess effectiveness and toxicity levels of stereotactic radiation therapy without whole brain radiation therapy in patients with solitary brain metastases larger than 3cm.

PATIENTS AND METHODS

Between June 2007 and March 2009, 12 patients received fractionated stereotactic radiation therapy and 24 patients underwent stereotactic radiosurgery. For the fractionated stereotactic radiation therapy group, 3×7.7Gy were delivered to the planning target volume (PTV); median volume and diameter were 29.4 cm(3) and 4.4cm, respectively. For the stereotactic radiosurgery group, 14Gy were delivered to the PTV; median volume and diameter were 15.6 cm(3) and 3.7cm, respectively.

RESULTS

Median follow-up was 218 days. For the fractionated stereotactic radiation therapy group, local control rates were 100% at 360 days and 64% at 720 days; for the stereotactic radiosurgery group, rates were 58% at 360 days and 48% at 720 days (P=0.06). Median survival time was 504 days for the fractionated stereotactic radiation therapy group and 164 days for the stereotactic radiosurgery group (P=0.049). Two cases of grade 2 toxicity were observed in the fractionated stereotactic radiation therapy group, and 6 cases of grade 1-2 toxicity, in the stereotactic radiosurgery group.

CONCLUSIONS

This study provides data to support that fractionated stereotactic radiation therapy without whole brain radiation therapy with a margin dose of 3 fractions of 7.7Gy for treatment of solitary large brain metastases is efficient and well-tolerated. Because of the significant improvement in overall survival, this schedule should be assessed in a randomized trial.

Effects of endurance training on the maximal voluntary activation level of the knee extensor muscles

PURPOSE

The aim of this study was to investigate the neural adaptations to endurance training, and more specifically the adaptation of the cortical voluntary activation of the knee extensor (KE) muscles.

METHODS

Sixteen sedentary men were randomly allocated into an endurance training (n = 8) or a control group (n = 8). All subjects performed a maximal aerobic speed test (MAS) before and immediately after the training period. Training lasted 8 weeks and was based on endurance running. During Pre- and Post-training testing sessions, maximal voluntary contraction (MVC) was measured and voluntary activation (VA) was calculated via peripheral nerve (PNS) and transcranial magnetic stimulations (TMS) superimposed to MVC. Electromyographic activity (EMG) of the KE muscles was also measured during MVC, PNS (M-wave) and TMS (motor evoked potentials-MEP). The cortical silent period following TMS was also assessed.

RESULTS

Despite a significant improvement in endurance running performance, as suggested by the increase of MAS in the training group (Pre 15.4 ± 1.6 vs. Post 16.4 ± 1.6 km·h(-1)), endurance training did not affect MVC or VA as measured with PNS and TMS. Similarly, the EMG of KE muscles during MVC did not show any significant changes. Furthermore, the MEP amplitude and the duration of the silent period also remained unchanged after endurance training.

CONCLUSIONS

The present study suggests an 8-week endurance-training program does not generate adaptations of neural factors in sedentary subjects.

Synthesis of medicinally useful lipidicα-amino acids, 2-amino alcohols and diamines

The lipidicα-amino acids (LAAs) are non-naturalα-amino acids with saturated or unsaturated long aliphatic side chains. LAAs and their derivatives (lipid mimetics) together with the lipidic peptides represent a class of compounds which combine structural features of lipids with those of amino acids and peptides. Racemic LAAs may be prepared by classical methods and resolved by chemical or enzymatic methods. LAA amides and esters with saturated or unsaturated long chain amines and alcohols respectively, as well as lipidic dipeptide derivatives inhibit both pancreatic and human platelet phospholipase A2. Lipophilic peptide derivatives are inhibitors of human neutrophil elastase. LAAs and their oligomers have been used as drug delivery system. A Lipid-Core-Peptide system has been designed and used as a combined adjuvant-carrier-vaccine system. A variety of lipid mimetics such as lipidic 2-amino alcohols, lipidic 1,2- and 1,3-diamines have been prepared based upon LAAs. Some of them are potent inhibitors of phospholipase A2. A general approach to enantioselective synthesis of LAAs and lipid mimetics is based on the oxidative cleavage of 3-amino-1,2-diols obtained by the regioselective opening of enantiomerically enriched long chain 2,3-epoxy alcohols.

EGFR, KRAS, BRAF, and PIK3CA characterization in squamous cell anal cancer

BACKGROUND

Combined chemoradiation therapy is the gold standard in the treatment of squamous cell anal cancer (SCAC). However, even if the response rate is very high, many patients eventually relapse or experience a reccurrence, thus requiring an invasive surgical procedure that has severe side effects. Most SCAC tumors overexpress epidermal growth factor receptor (EGFR); therefore, it is reasonable to consider anti-EGFR drugs as a new treatment option, as demonstrated by anecdotal reports. Promising results obtained in other solid tumors, both squamous and non-squamous, have revealed that an increase in the EGFR gene copy number may predict the efficacy of anti-EGFR therapies, while the presence of mutations in downstream members of the EGFR pathway may confer resistance. These markers have been only sporadically considered in SCAC.

METHODS

We investigated the status of the EGFR gene using FISH and examined KRAS, BRAF, and PIK3CA hot-spots mutations using sequencing analysis in a cohort of 84 patients affected by SCAC.

RESULTS

Twenty-eight patients (34%) showed an increase in EGFR gene copy number due to amplification (4%) or to polysomy (30%). KRAS and PIK3CA gene mutations were found in 4 (5%) and 13 patients (16%), respectively. No mutations were found in the BRAF gene.

CONCLUSIONS

The characterization of the EGFR pathway may help in identifying different subgroups of SCAC that have specific molecular features, which may have implications in what targeted therapies are used to treat each patient.

The combined expression of the stromal markers fibronectin and SPARC improves the prediction of survival in diffuse large B-cell lymphoma

Background

In diffuse large B-cell lymphomas, gene expression profiling studies attributed a major biologic role to non-neoplastic cells of the tumour microenvironment as its composition and characteristics were shown to predict survival. In particular, the expression of selected genes encoding components of the extracellular matrix was reported to be associated with clinical outcome. Nevertheless, the translation of these data into robust, routinely applicable immunohistochemical markers is still warranted. Therefore, in this study, we analysed the combination of the expression of the extracellular matrix components Fibronectin and SPARC on formalin-fixed paraffin embedded tissue derived from 173 patients with DLBCL in order to recapitulate gene expression profiling data.

Results

The expression of Fibronectin and SPARC was detected in 77/173 (44.5%) and 125/173 (72.3%) cases, respectively, and 55/173 (31.8%) cases were double positive. Patients with lymphomas expressing Fibronectin showed significantly longer overall survival when compared to negative ones (6.3 versus 3.6 years). Moreover, patients with double positive lymphomas also presented with significantly longer overall survival when compared with the remaining cases (11.6 versus 3.6 years) and this combined expression of both markers results in a better association with overall survival data than the expression of SPARC or Fibronectin taken separately (Hazard ratio 0.41, 95% confidence interval 0.17 to 0.95, p = 0.037). Finally, neither Fibronectin nor SPARC expression was associated with any of the collected clinico-pathological parameters.

Conclusions

The combined immunohistochemical assessment of Fibronectin and SPARC, two components of the extracellular matrix, represents an important tool for the prediction of survival in diffuse large B-cell lymphomas. Our study suggests that translation of gene expression profiling data on tumour microenvironment into routinely applicable immunohistochemical markers is a useful approach for a further characterization of this heterogeneous type of lymphoma.

The combined expression of VPREB3 and ID3 represents a new helpful tool for the routine diagnosis of mature aggressive B-cell lymphomas

Genomic studies, such as gene expression profiling and next-generation sequencing studies, have provided new insights into the phenotypic characteristics and pathogenesis of mature aggressive B-cell lymphomas. In particular, mutations in the transcription factors ID3 and TCF3, leading to overexpression of B-cell receptor components such as VPREB3, have been shown to be specific for Burkitt lymphoma (BL) and play an important tumourigenic role by mediating the activation of the pro-survival phosphatidylinositol-3-OH kinase pathway. We performed immunohistochemical analysis by applying commercially available anti-VPREB3 antibody to a large cohort of 185 genetically and immunophenotypically characterized mature aggressive B-cell lymphomas and analyzed these results together with recent data on ID3 expression. The combined expression of both VPREB3 and ID3 was associated with a diagnosis of BL with high sensitivity (0.77), high specificity (0.75) and high negative predictive values (0.96), however, with lower positive predictive value (0.30). Double negative cases were absent in the group of BLs but could be found in approximately one third of the remaining cases of mature aggressive B-cell lymphomas. Further, we could not identify a correlation with MYC, BCL2 or BCL6 aberrations with neither VPREB3 nor ID3 expression in each of the diagnostic groups analyzed. Our results, which are in line with recently discovered mutations in next-generation sequencing studies, suggest that the combined immunohistochemical detection of VPREB3 and ID3 is applicable to the routine diagnostic in case of mature aggressive B-cell lymphomas. In particular, it represents a useful and routinely applicable diagnostic tool to exclude BL diagnosis in case of single positive or double negative cases.

Dynamic Stark spectroscopic measurements of microwave electric fields inside the plasma near a high-power antenna

Fully dynamic Stark effect visible spectroscopy was used for the first time to directly measure the local rf electric field in the boundary plasma near a high-power antenna in high-performance, magnetically confined, fusion energy experiment. The measurement was performed in the superconducting tokamak Tore Supra, in the near field of a 1–3 MW, lower-hybrid, 3.7 GHz wave-launch antenna, and combined with modeling of neutral atom transport to estimate the local rf electric field amplitude (as low as 1–2 kV/cm) and direction in this region. The measurement was then shown to be consistent with the predicted values from a 2D full-wave propagation model. Notably the measurement confirmed that the electric field direction deviates substantially from the direction in which it is launched by the waveguides as it penetrates only a few cm radially inward into the plasma from the waveguides, consistent with the model.

UV filters for hair protection

Synopsis Hair damage, caused by sunlight, and the possibility to protect hair against sunlight by means of cosmetic formulations was studied. For this, five UV-filters were tested: benzophenone-3 (UV-A/UV-B); benzophenone-4 (UV-A/UV-B); phenylbenzimidazole sulfonic acid (UV-B); butylmethoxydibenzoylmethane (UV-A); octyl dimethyl PABA (UV-B). The stability of the UV-filters was tested as pure substances as well as in two cosmetic formulations: a setting lotion and a shine spray. The degree of decolouration and stress strain behaviour were determined. The benzophenones had the best protection ability both on colour and on morphology. Stability data and UV-spectra are discussed.

A protection system for the JET ITER-like wall based on imaging diagnostics

The new JET ITER-like wall (made of beryllium and tungsten) is more fragile than the former carbon fiber composite wall and requires active protection to prevent excessive heat loads on the plasma facing components (PFC). Analog CCD cameras operating in the near infrared wavelength are used to measure surface temperature of the PFCs. Region of interest (ROI) analysis is performed in real time and the maximum temperature measured in each ROI is sent to the vessel thermal map. The protection of the ITER-like wall system started in October 2011 and has already successfully led to a safe landing of the plasma when hot spots were observed on the Be main chamber PFCs. Divertor protection is more of a challenge due to dust deposits that often generate false hot spots. In this contribution we describe the camera, data capture and real time processing systems. We discuss the calibration strategy for the temperature measurements with cross validation with thermal IR cameras and bi-color pyrometers. Most importantly, we demonstrate that a protection system based on CCD cameras can work and show examples of hot spot detections that stop the plasma pulse. The limits of such a design and the associated constraints on the operations are also presented.

Modeling of the ITER-like wide-angle infrared thermography view of JET

Infrared (IR) thermography systems are mandatory to ensure safe plasma operation in fusion devices. However, IR measurements are made much more complicated in metallic environment because of the spurious contributions of the reflected fluxes. This paper presents a full predictive photonic simulation able to assess accurately the surface temperature measurement with classical IR thermography from a given plasma scenario and by taking into account the optical properties of PFCs materials. This simulation has been carried out the ITER-like wide angle infrared camera view of JET in comparing with experimental data. The consequences and the effects of the low emissivity and the bidirectional reflectivity distribution function used in the model for the metallic PFCs on the contribution of the reflected flux in the analysis are discussed.

Molecular characterization of EGFR and EGFR-downstream pathways in triple negative breast carcinomas with basal like features

AIMS

Triple negative breast cancer with basal like features (TN-BCBL) do not benefit from hormonal and anti-HER2 therapies. As a considerable fraction of TN-BCBLs shows EGFR deregulation, EGFR-targeted therapies have been proposed as an option. The characterization of EGFR and EGFR-downstream members may therefore provide important predictive information.

METHODS AND RESULTS

Based on morphological and immunophenotypic features, we identified 38 TN-BCBLs that were subsequently investigated for alterations in EGFR signaling pathways. EGFR and PTEN protein levels were studied by immunohistochemistry, EGFR gene status by FISH, EGFR, H-Ras, K-Ras, N-Ras, BRAF and PIK3CA gene mutations by direct sequencing. EGFR overexpression and loss of PTEN expression characterized the majority of TN-BCBLs (76% and 74% of patients, respectively). EGFR gene copy number gain (FISH+) was identified in 51% of analyzable patients. PIK3CA gene mutations were detected in three cases (8%), whereas EGFR, H-Ras, K-Ras, N-Ras and BRAF genes showed no mutations. Overall, out of 17 patients classified as FISH+, 12 cases (70%) showed a concomitant alteration in PI3K/PTEN pathway.

CONCLUSIONS

These results provide evidence that the efficacy of anti-EGFR drugs in TN-BCBL patients could be impaired by frequent alterations in the PI3K/PTEN axis, and suggest that TN-BCBLs could benefit from tailored treatments against this axis.

Fas/Fas ligand regulation mediates cell death in human Ewing's sarcoma cells treated with melatonin

Background:

Despite recent advances in cancer therapy, the 5-year survival rate for Ewing's sarcoma is still very low, and new therapeutic approaches are necessary. It was found previously that melatonin induces cell death in the Ewing's sarcoma cell line, SK-N-MC, by activating the extrinsic apoptotic pathway.

Methods:

Melatonin actions were analysed by metabolic viability/survival cell assays, flow cytometry, quantitative PCR for mRNA expression, western blot for protein activation/expression and electrophoretic mobility shift assay for transcription factor activation.

Results:

Melatonin increases the expression of Fas and its ligand Fas L, this increase being responsible for cell death induced by the indolamine. Melatonin also produces a transient increase in intracellular oxidants and activation of the redox-regulated transcription factor Nuclear factor-kappaB. Inhibition of such activation prevents cell death and Fas/Fas L upregulation. Cytotoxic effect and Fas/Fas L regulation occur in all Ewing's cell lines studied, and do not occur in the other tumour cell lines studied where melatonin does not induce cell death.

Conclusion:

Our data offers new insights in the study of alternative therapeutic strategies in the treatment of Ewing's sarcoma. Further attention deserves to be given to the differences in the cellular biology of sensitive tumours that could explain the cytotoxic effect of melatonin and the increase in the level of free radicals caused by this molecule, in particular cancer types.

Effects of oestradiol on brain lipid class and Fatty Acid composition: comparison between pregnant and ovariectomised oestradiol-treated rats

To determine the involvement of physiological doses of oestradiol on brain lipid composition, we have analysed the lipid class and fatty acid composition of phospholipids in the brain from pregnant and 17β-oestradiol-treated rats. Rats were randomly divided into three groups: ovariectomised control (OVX + VEH), ovariectomised oestradiol-treated (OVX + E(2) ) and pregnant (PREG) rats. Rats from the OVX + E(2) group were injected daily with different doses of 17β-oestradiol mimicking the plasma levels observed during pregnancy. Analyses of brain lipid class composition showed that physiological doses of oestradiol increased cholesterol levels of the OVX + E(2) group compared to the OVX + VEH group. It was also found that cholesterol levels in the PREG group were significantly lower than in the OVX + VEH and OVX + E(2) groups, indicating the involvement of gestational hormones other than oestradiol in the regulation of brain cholesterol during pregnancy. Brains from pregnant rats also exhibited reduced levels of plasmalogens and saturated fatty acids compared to the ovariectomised groups, especially in the second half of pregnancy. Interestingly, analyses of fatty acid composition of phospholipids revealed that physiological doses of oestradiol increased brain docosahexaenoic acid (DHA; 22:6 n-3) levels. Moreover, DHA levels in pregnant rats were similar to those observed in the OVX + E(2) group at all stages, suggesting that oestradiol is the main hormone in the regulation of brain DHA levels during pregnancy. Liver appears to be the major source for n-3 and n-6 long chain polyunsaturated fatty acids (LCPUFAs) DHA and arachidonic acid, which are released and transported to the maternal brain and the developing foetus under the influence of oestrogens. We also observed that the largest depots of n-3 and n-6 LCPUFA precursors (linolenic acid and linoleic acid, respectively) occur in adipose tissue triglycerides, which, in turn are significantly increased during pregnancy. Our observations are in accordance with an oestradiol-induced increased bioavailability of brain DHA in pregnant rats. We hypothesise that the reduction of maternal brain DHA observed at the end of pregnancy is a result of the very high demand DHA of foetal brain, which overcomes the maximal maternal (and likely foetal) capacity for de novo DHA synthesis in the liver and brain.

Use of HER2 gene amplification to identify patients with metastatic colorectal cancer resistant to anti-EGFR monoclonal antibodies

474

Background: KRAS mutation represents the only validated biomarker used in clinical practice for selection of metastatic colorectal cancer (mCRC) candidates for therapy with the anti-Epidermal Growth Factor Receptor (EGFR) monoclonal antibodies. Previous studies conducted in small cohorts of patients suggested that HER2, the major EGFR partner, could modify the sensitivity to anti-EGFR agents. Aim of the present study was to investigate the role of HER2 gene status in a cohort of mCRC patients treated with cetuximab or panitumumab.

Methods: 266 chemorefractory mCRC patients treated with cetuximab or panitumumab alone or in combination with chemotherapy were collected in an international consortium effort. HER2 gene status was analyzed using the dual-color FISH assay LSI HER2/neu-CEP17 (PATHVYSION, Abbott) in one central lab, whereas KRAS/BRAF mutations were investigated locally. HER2 gene amplification was defined as the presence of a ratio between HER2 gene and chromosome 17 centromere > 2.

Results: An objective response to anti-EGFR therapy (complete or partial response according to RECIST criteria) was observed in 79/266 (29%) of patients. Twelve cases (4.5%) showed the classical pattern of HER2 gene amplification (R>2) in the whole tissue (>80% of tumor cells). By matching HER2 gene status with clinical response we observed that HER2 gene amplification was significantly related to therapy resistance (p<0.0001). Moreover, analysis of follow-up data indicated that HER2 gene amplification was significantly associated with a worse progression free survival (PFS, p=0.0025) and with a trend for a worse overall survival (p=0.062). Similar associations were also observed in the KRAS/BRAF wild-type patients.

Conclusions: Data from this large retrospective study suggest that HER2 gene status evaluated by FISH may represent an additional marker useful for the prediction of mCRC patients’ response to EGFR-targeted therapies, in line with very recent evidence. In particular, patients with HER2 gene amplification seem to be resistant and show a shorter PFS. Future studies are needed to deeply investigate the clinical and biological meaning of HER2 gene status deregulation in mCRC.

Standardisation of EGFR FISH in colorectal cancer: results of an international interlaboratory reproducibility ring study

AIMS

Epidermal growth factor receptor (EGFR) gene copy number evaluated by fluorescence in situ hybridisation (FISH) can discriminate among KRAS wild-type patients those with better outcome to EGFR-targeted therapy in metastatic colorectal cancer, further enhancing selection of patients. Nevertheless, enumeration of gene copies is challenging and the lack of analytical standardisation has limited incorporation of the test into the clinical practice. We therefore assessed EGFR FISH interlaboratory consensus among five molecular diagnostic reference centres.

METHODS

A set of 12 colorectal cancer samples circulated among laboratories, and samples were scored according to commonly agreed guidelines. Reproducibility was quantified using the standard error of measurement (SEM).

RESULTS

A SEM of 0.865 and a within-subject coefficient of variation (WSCV) of 26.8% for mean EGFR gene/nuclei and a SEM of 0.235 and a WSCV of 19.4% for the mean EGFR gene/CEP7 ratio were observed. Measurement of the fraction of cells displaying chromosome 7 polysomy showed WSCV of 46.6%, 34.0% and 51.0% for percentage of cells displaying ≤2, ≥3 and ≥4 EGFR signals, respectively. Among different slides of the same specimen, the WSCV was 6.1% for mean EGFR gene/nuclei and 3.9% for mean of EGFR gene/CEP7 ratios.

CONCLUSIONS

Molecular diagnosis of EGFR gene copy number by FISH varied largely among pathology centres, with fluctuations covering the whole range of proposed cut-offs of predictive usefulness from literature. Definition of a detailed scoring system and implementation of comprehensive training programmes for laboratories are therefore necessary before including the test into clinical practice.

The Syk-kinase inhibitor R406 impairs platelet activation and monocyte tissue factor expression triggered by heparin-PF4 complex directed antibodies

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is a rare but severe complication of heparin therapy in which immunoglobulin G (IgG) antibodies against the platelet factor 4-heparin complex activate platelets through the FcγRIIA receptor. Clustering of FcγRIIA initiates signaling cascades involving tyrosine kinases including the spleen tyrosine kinase (Syk). Moreover, besides the critical role of platelets, the expression of tissue factor (TF) by human monocytes triggered by HIT antibodies has been shown to contribute to the hypercoagulability and the thrombotic complications in HIT patients.

OBJECTIVES

We investigated the effect of R406, a small molecule inhibitor of Syk developed as a potential treatment of autoimmune diseases, allergic disorders and B-cell related hematological malignancies, on FcγRIIA-mediated platelet activation. To further assess the potential activity of Syk inhibitors in HIT treatment, the effect of R406 was also evaluated on HIT antibodies-induced expression of TF and procoagulant activity of monocytic cells.

RESULTS

We show that R406 is a potent inhibitor of platelet signaling and functions initiated by FcγRIIA cross-linking by specific antibodies or by sera from HIT patients. Syk inhibition efficiently prevents FcγRIIA-induced LAT phosphorylation and activation of phosphoinositide 3-kinase, Akt, phospholipase Cγ2 and p38 MAP-kinase. As a consequence, FcγRIIA-induced platelet aggregation, granule secretion and microparticles production are strongly inhibited by R406. Moreover, the Syk inhibitor efficiently impairs the expression of TF and the procoagulant activity of human monocytes triggered by HIT antibodies.

CONCLUSION

Syk inhibitors may be of therapeutic interest in the treatment of HIT by reducing HIT antibodies-mediated platelet activation and monocyte procoagulant activity.