Genetic redox dysregulation induces behavioural deficits in the adult mouse: an animal model for schizophrenia

Background: Glutathione (GSH), a major cellular redox regulator and antioxidant, is decreased in cerebrospinal fluid and prefrontal cortex of schizophrenia patients. The gene of the key GSH-synthesizing enzyme, glutamate-cysteine ligase, modifier (GCLM) subunit, is associated with schizophrenia, suggesting that the deficit in the GSH system is of genetic origin. Using the GCLM knock-out (KO) mouse as model system with 60% decreased brain GSH levels and, thus, strong vulnerability to oxidative stress, we have shown that GSH dysregulation results in abnormal mouse brain morphology (e.g., reduced parvalbumin, PV, immuno-reactivity in frontal areas) and function. Additional oxidative stress, induced by GBR12909 (a dopamine re-uptake inhibitor), enhances morphological changes even further. Aim: In the present study we use the GCLM KO mouse model system, asking now, whether GSH dysregulation also compromises mouse behaviour and cognition. Methods: Male and female wildtype (WT) and GCLM-KO mice are treated with GBR12909 or phosphate buffered saline (PBS) from postnatal day (P) 5 to 10, and are behaviourally tested at P 60 and older. Results: In comparison to WT, KO animals of both sexes are hyperactive in the open field, display more frequent open arm entries on the elevated plus maze, longer float latencies in the Porsolt swim test, and more frequent contacts of novel and familiar objects. Contrary to other reports of animal models with reduced PV immuno-reactivity, GCLM-KO mice display normal rule learning capacity and perform normally on a spatial recognition task. GCLM-KO mice do, however, show a strong deficit in object-recognition after a 15 minutes retention delay. GBR12909 treatment exerts no additional effect. Conclusions: The results suggest that animals with impaired regulation of brain oxidative stress are impulsive and have reduced behavioural control in novel, unpredictable contexts. Moreover, GSH dysregulation seems to induce a selective attentional or stimulus-encoding deficit: despite intensive object exploration, GCLM-KO mice cannot discriminate between novel and familiar objects. In conclusion, the present data indicate that GSH dysregulation may contribute to the manifestation of behavioural and cognitive anomalies that are associated with schizophrenia.

Impact of genomic methylation on radiation sensitivity of colorectal carcinoma.

PURPOSE: To investigate the influence of demethylation with 5-aza-cytidine (AZA) on radiation sensitivity and to define the intrinsic radiation sensitivity of methylation deficient colorectal carcinoma cells. METHODS AND MATERIALS: Radiation sensitizing effects of AZA were investigated in four colorectal carcinoma cell lines (HCT116, SW480, L174 T, Co115), defining influence of AZA on proliferation, clonogenic survival, and cell cycling with or without ionizing radiation. The methylation status for cancer or DNA damage response-related genes silenced by promoter methylation was determined. The effect of deletion of the potential target genes (DNMT1, DNMT3b, and double mutants) on radiation sensitivity was analyzed. RESULTS: AZA showed radiation sensitizing properties at >or=1 micromol/l, a concentration that does not interfere with the cell cycle by itself, in all four tested cell lines with a sensitivity-enhancing ratio (SER) of 1.6 to 2.1 (confidence interval [CI] 0.9-3.3). AZA successfully demethylated promoters of p16 and hMLH1, genes associated with ionizing radiation response. Prolonged exposure to low-dose AZA resulted in sustained radiosensitivity if associated with persistent genomic hypomethylation after recovery from AZA. Compared with maternal HCT116 cells, DNMT3b-defcient deficient cells were more sensitive to radiation with a SER of 2.0 (CI 0.9-2.1; p = 0.03), and DNMT3b/DNMT1-/- double-deficient cells showed a SER of 1.6 (CI 0.5-2.7; p = 0.09). CONCLUSIONS: AZA-induced genomic hypomethylation results in enhanced radiation sensitivity in colorectal carcinoma. The mediators leading to sensitization remain unknown. Defining the specific factors associated with radiation sensitization after genomic demethylation may open the way to better targeting for the purpose of radiation sensitization.

Developmental, metabolic and immunological costs of flea infestation in the common vole

Parasites use resources from their hosts, which can indirectly affect a number of host functions because of trade-offs in resource allocation. In order to get a comprehensive view of the costs imposed by blood sucking parasites to their hosts, it is important to monitor multiple components of the development and physiology of parasitized hosts over long time periods. The effect of infestation by fleas on body mass, body length growth, haematocrit, resistance to oxidative stress, resting metabolic rate and humoral immune response were experimentally evaluated. During a 3-month period, male common voles, Microtus arvalis, were either parasitized by rat fleas (Nosopsyllus fasciatus), which are naturally occurring generalist ectoparasites of voles, or reared without fleas. Then voles were challenged twice by injecting Keyhole Limpet Haemocyanin (KLH) to assess whether the presence of fleas affects the ability of voles to produce antibodies against a novel antigen. During the immune challenge we measured the evolution of body mass, haematocrit, resistance to oxidative stress and antibody production. Flea infestation negatively influenced the growth of voles. Moreover, parasitized voles had reduced haematocrit, higher resting metabolic rate and lower production of antibodies against the KLH. Resistance to oxidative stress was not influenced by the presence of fleas. During the immune challenge with KLH, body mass decreased in both groups, while the resistance to oxidative stress remained stable. In contrast, the haematocrit decreased only in parasitized voles. Our experiment shows that infestation by a haematophageous parasite negatively affects multiple traits like growth, energy consumption and immune response. Fleas may severely reduce the survival probability and reproductive success of their host in natural conditions.

Predictors of the risk of fibrosis at 10 years after breast conserving therapy for early breast cancer: a study based on the EORTC Trial 22881-10882 'boost versus no boost'.

The EORTC 22881-10882 trial in 5178 conservatively treated early breast cancer patients showed that a 16 Gy boost dose significantly improved local control, but increased the risk of breast fibrosis. To investigate predictors for the long-term risk of fibrosis, Cox regression models of the time to moderate or severe fibrosis were developed on a random set of 1797 patients with and 1827 patients without a boost, and validated in the remaining set. The median follow-up was 10.7 years. The risk of fibrosis significantly increased (P<0.01) with increasing maximum whole breast irradiation (WBI) dose and with concomitant chemotherapy, but was independent of age. In the boost arm, the risk further increased (P<0.01) if patients had post-operative breast oedema or haematoma, but it decreased (P<0.01) if WBI was given with >6 MV photons. The c-index was around 0.62. Nomograms with these factors are proposed to forecast the long-term risk of moderate or severe fibrosis.

European cancer mortality predictions for the year 2011.

Background: Mortality figures become available after some years.Materials and methods: Using the World Health Organization mortality and population data, we estimated numbers of deaths in 2011 from all cancers and selected sites for the European Union (EU) and six major countries, by fitting a joinpoint model to 5-year age-specific numbers of deaths. Age-standardized rates were computed using EUROSTAT population estimates.Results: The predicted number of cancer deaths in the EU in 2011 was 1 281 436, with standardized rates of 143/100 000 men and 85/100 000 women. Poland had the highest rates, with smaller falls over recent periods. Declines in mortality for major sites including stomach, colorectum, breast, uterus, prostate and leukemias, plus male lung cancer, will continue until 2011, and a trend reversal or a leveling off is predicted where upward trends were previously observed. Female lung cancer rates are increasing in all major EU countries except the UK, where it is the first cause of cancer death, as now in Poland. The increasing pancreatic cancer trends in women observed up to 2004 have likely leveled off.Conclusions: Despite falls in rates, absolute numbers of cancer deaths are stable in Europe. The gap between Western and former nonmarket economy countries will likely persist.

Prolonged survival for patients with newly diagnosed, inoperable glioblastoma with 3-times daily ultrafractionated radiation therapy.

Ultrafractionation of radiation therapy is a novel regimen consisting of irradiating tumors several times daily, delivering low doses (<0.75 Gy) at which hyperradiosensitivity occurs. We recently demonstrated the high efficiency of ultrafractionated radiotherapy (RT) on glioma xenografts and report here on a phase II clinical trial to determine the safety, tolerability, and efficacy of an ultrafractionation regimen in patients with newly and inoperable glioblastoma (GBM). Thirty-one patients with histologically proven, newly diagnosed, and unresectable supratentorial GBM (WHO grade IV) were enrolled. Three daily doses of 0.75 Gy were delivered at least 4 hours apart, 5 days per week over 6-7 consecutive weeks (90 fractions for a total of 67.5 Gy). Conformal irradiation included the tumor bulk with a margin of 2.5 cm. The primary end points were safety, toxicity, and tolerability, and the secondary end points were overall survival (OS) and progression-free survival (PFS). Multivariate analysis was used to compare the OS and PFS with the EORTC-NCIC trial 26981-22981/CE.3 of RT alone vs radiation therapy and temozolomide (TMZ). The ultrafractionation radiation regimen was safe and well tolerated. No acute Grade III and/or IV CNS toxicity was observed. Median PFS and OS from initial diagnosis were 5.1 and 9.5 months, respectively. When comparing with the EORTC/NCIC trial, in both PFS and OS multivariate analysis, ultrafractionation showed superiority over RT alone, but not over RT and TMZ. The ultrafractionation regimen is safe and may prolong the survival of patients with GBM. Further investigation is warranted and a trial associating ultra-fractionation and TMZ is ongoing.

Safety, pharmacokinetics, and preliminary clinical activity of inotuzumab ozogamicin, a novel immunoconjugate for the treatment of B-cell non-Hodgkin's lymphoma: results of a phase I study.

PURPOSE Inotuzumab ozogamicin (CMC-544) is an antibody-targeted chemotherapy agent composed of a humanized anti-CD22 antibody conjugated to calicheamicin, a potent cytotoxic agent. This was a phase I study to determine the maximum-tolerated dose (MTD), safety, and preliminary efficacy of inotuzumab ozogamicin in an expanded MTD cohort of patients with relapsed or refractory CD22(+) B-cell non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS Inotuzumab ozogamicin was administered intravenously as a single agent once every 3 or 4 weeks at doses ranging from 0.4 to 2.4 mg/m(2). Outcomes included MTD, safety, pharmacokinetics, response, progression-free survival (PFS), and overall survival. Results Seventy-nine patients were enrolled. The MTD was determined to be 1.8 mg/m(2). Common adverse events at the MTD were thrombocytopenia (90%), asthenia (67%), and nausea and neutropenia (51% each). The objective response rate at the end of treatment was 39% for the 79 enrolled patients, 68% for all patients with follicular NHL treated at the MTD, and 15% for all patients with diffuse large B-cell lymphoma treated at the MTD. Median PFS was 317 days (approximately 10.4 months) and 49 days for patients with follicular NHL and diffuse large B-cell lymphoma, respectively. CONCLUSION Inotuzumab ozogamicin has demonstrated efficacy against CD22(+) B-cell NHL, with reversible thrombocytopenia as the main toxicity.

Imatinib plasma concentrations variability in oncologic patients

The anticancer drug imatinib has transformed the treatment and prognosis of chronic myeloid leukemia and gastrointestinal stromal tumor. However, the treatment must be taken indefinitely and is not devoid of inconveniences and toxicity. Moreover, resistance or escape from disease control are occurring. Considering the large interindividual differences in the function of the enzymatic and transport systems involved in imatinib disposition, exposure to this drug can be expected to vary widely among patients. This book describes an observational clinical trial aiming at exploring the influence of these covariates on imatinib pharmacokinetics and assessing the interindividual variability of the pharmacokinetic parameters of the drug. A large interindividual variability was observed, together with some preliminary concentration-effect relationships. These elements are arguments to further investigate the potential benefit of a therapeutic drug monitoring program to optimize the use of imatinib in patients. Such results should be especially useful to clinical oncologists or scientists involved in clinical oncology research.

Outcome and Prognostic Factors in Adenosquamous Carcinoma of the Head and Neck - a Multicenter Rare Cancer Network Study

Background: Adenosquamous carcinoma (AC) of the head and neck is a distinct entity first described in 1968. Its natural history is more aggressive than squamous-cell carcinoma. The aim of this study was to assess the clinical profile, patterns of failure, and prognostic factors in patients with AC of the head and neck treated by radiation therapy (RT) with or without chemotherapy (CT).Materials and Methods: Data from 19 patients with stage I (n = 3), II (n = 1), III (n = 4), or IVa (n = 11) AC, treated between 1989 and 2009, were collected in a retrospective multicenter Rare Cancer Network study. Median age was 60 years (range, 48−73). Fifteen patients were male, and 4 female. Risk factors, including perineural invasion, lymphangitis, vascular invasion, positive margins were present in the majority (83%) of the patients. Tumour sites included oral cavity in 4, oropharynx in 4, hypopharynx in 2, larynx in 2, salivary glands in 2, nasal vestibule in 2, maxillary sinus in 2, and nasopharynx in 1 patient. Surgery (S) was performed in all but 5 patients. S alone was performed in only 1 patient, and definitive RT alone in 3 patients. Fifteen patients received combined modality treatment (S+RT in 11, RT+CT in 2, and all of the three modalities in 2 patients). Median RT dose to the primary and to the nodes was 66 Gy (range, 50−72) and 53 Gy (range, 44−66), respectively (1.8−2.0 Gy/fr., 5 fr./week). In 4 patients, the planning treatment volume included the primary tumour site only. Eight patients were treated with 2D RT, 7 with 3D conformal RT, and 2 with intensity-modulated RT.Results: After a median follow-up period of 39 months (range, 9−62), 9 patients developed distant metastases (lung, bone, mediastinum, and liver), 7 presented nodal recurrences, and only 4 had a local relapse at the primary site (all in-field recurrences). At last follow-up, 7 patients were alive without disease, 1 alive with disease, 9 died from progressive disease, and 2 died from intercurrent disease. The 3-year and median overall survival, disease-free survival (DFS), and locoregional control rates were 55% (95% confidence interval [CI]: 32−78%) and 39 months, 34% (95% CI: 12−56%) and 22 months, and 50% (95% CI: 22−78%) and 33 months, respectively. In multivariate analysis (Cox model), DFS was negatively influenced by the presence of extracapsular extension (p = 0.01) and advanced stage (IV versus I−III, p = 0.002).Conclusions: Overall prognosis of locoregionally advanced AC remains poor, and distant metastases and nodal relapse occur in almost half of the cases. However, local control is relatively better, and early stage AC patients had prolonged DFS when treated with combined-modality treatment.

Epidemiology of biliary tract cancers: an update

BACKGROUND: Biliary tract cancer (BTC) is a rare cancer in Europe and North America, characterized by wide geographic variation, with high incidence in some areas of Latin America and Asia. MATERIALS AND METHODS: BTC mortality and incidence have been updated according to recent data, using joinpoint regression analysis. RESULTS: Since the 1980s, decreasing trends in BTC mortality rates (age-standardized, world standard population) were observed in the European Union as a whole, in Australia, Canada, Hong Kong, Israel, New Zealand, and the United States, and high-risk countries such as Japan and Venezuela. Joinpoint regression analysis indicates that decreasing trends were more favorable over recent calendar periods. High-mortality rates are, however, still evident in central and eastern Europe (4-5/100,000 women), Japan (4/100,000 women), and Chile (16.6/100,000 women). Incidence rates identified other high-risk areas in India (8.5/100,000 women), Korea (5.6/100,000 women), and Shanghai, China (5.2/100,000 women). CONCLUSIONS: The decreasing BTC mortality trends essentially reflect more widespread and earlier adoption of cholecystectomy in several countries, since gallstones are the major risk factor for BTC. There are, however, high-risk areas, mainly from South America and India, where access to gall-bladder surgery remains inadequate.

Carotid Dose Spring in Definitive Irradiation of T1N0 Squamous Cell Laryngeal Carcinoma Using Helical Tomotherapy

Purpose/Objective(s): To implement a carotid dose sparing protocol using helical Tomotherapy in T1N0 squamous cell laryngeal carcinoma.Materials/Methods: Between July and August 2010, 7 men with stage T1N0 laryngeal carcinoma were included in this study. Age ranged from 47 - 74 years. Staging included endoscopic examination, CT-scan and MRI when indicated. Planned irradiation dose was 70 Gy in 35 fractions over 7 weeks. A simple treatment planning algorithm for carotid sparing was used: maximum point dose to the carotids 35 Gy, to the spinal cord 30 Gy, and 100% PTV volume to be covered with 95% of the prescribed dose. Carotid volume of interest extended to 1 cm above and below of the PTV. Doses to the carotid arteries, to the critical organs, and to the planned target volume (PTV) with our standard laryngeal irradiation protocol was compared. Daily megavoltage scans were obtained before each fraction. When necessary, the Planned Adaptive software (TomoTherapy Inc., Madison, WI) was used to evaluatethe need for a re-planning, which has never been indicated. Dose data were extracted using the VelocityAI software (Atlanta, GA), and data normalization and dose-volume histogram (DVH) interpolation were realized using the Igor Pro software (Portland, OR).Results:A significant (p\0.05) carotid dose sparing compared to our standard protocol with an average maximum point dose of 38.3 Gy (standard deviation [SD] 4.05 Gy), average mean dose of 18.59 Gy (SD 0.83 Gy) was achieved. In all patients, 95% of the carotid volume received less than 28.4 Gy (SD 0.98 Gy). The average maximum point dose to the spinal cord was 25.8 Gy (SD 3.24 Gy). PTV was fully covered with more than 95% of the prescribed dose for all patients with an average maximum point dose of 74.1 Gy and the absolute maximum dose in a single patient of 75.2 Gy. To date, the clinical outcomes have been excellent. Three patients (42%) developed stage 1 mucositis that was conservatively managed, and all the patients presented a mild to moderate dysphonia. All adverse effects resolved spontaneously in the month following the end of treatment. Early local control rate is 100% considering a 4 - 5 months post treatment follow-up.Conclusions: Helical Tomotherapy allows a clinically significant decrease of carotid irradiation dose compared to standard irradiation protocols with an acceptable spinal cord dose tradeoff. Moreover, this technique allows the PTV to be homogenously covered with a curative irradiation dose. Daily control imaging brings added security margins especially when working with high dose gradients. Further investigations and follow-up are underway to better evaluate the late clinical outcomes especially the local control rate, late laryngeal and vascular toxicity, and expected potential impact on cerebrovascular events.

Combined radiohormonotherapy in node positive lymph node prostate cancer

Purpose: Pelvic radiation therapy (RT) represents a therapeutic option in the treatment of node-positive prostate cancer but it remains controversial, because of its high rate toxicities. New radiation technique such as IMRT may reduce these complications. In this study, we aimed to assess the rate of toxicities according to CTC-NCI.v3 in such patients treated with either 3DCRT or IMRT (Tomotherapy).Methods and Materials: From January 2008 to December 2010, data were analyzed from 30 consecutive patients including 29 node-positive prostate cancer undergoing definitive or adjuvant RT (IMRT and/or 3DCRT) after radical prostatectomy and lymphadenectomy combined to hormonal therapy. Median age was 66 years (range : 52-83). Median preoperative PSA value was 12 ng/ml (range: 2.72-165). According to the pT-classification, there were 4 pT2, 7 pT3a, 10 pT3b, and 1 pT4 patients. Pathologic positive lymph nodes were found in 23 patients. Radiologic positive lymph nodes were found in 5 patients. Two patients were node negative. Gleason score was ranging between 7 to 10. Twelve patients were treated by Tomotherapy including 4 with simultaneous integrated boost (SIB). Eighteen patients were treated by Tomotherapy including 2 with SIB to the whole pelvis and 3DCRT boost to the prostate. V50% for bladder and rectum were recorded. Acute and late toxicities were assessed according to CTC-NCI.v3 classification.Results: With a median follow-up of 17 months, only one patient presented nodal and metastatic failure. Urinary incontinence was graded 1 after surgery for 6 patients and grade 2 in two. Sexual impuissance was noted in 3 patients. Acute toxicities during RT were proctitis grade 0 in 23 patients (76.5%), grade 1 in 7 (23.5%). Nocturia grade 1 in 9 patients. Interruption of treatment was seen in only case because of grade 3 urinary incontinence. Late effects included erectile dysfunction in 5 patients (83%) and one patient had grade 3proctitis requiring colostomy 3 months after RT. Median Dose-Volume Histogram according to radiation techniques V50% bladder V50% rectum Tomotherapy (IMRT) 36.25 Gy 39 Gy Tomotherapy + 3DCRT 41.26 Gy 39.18 GyConclusion: Based on our above-mentioned findings, there is no a significant difference in morbidity in patients treated with Tomotherapy or Tomotherapy with 3DCRT boost.