The effect of non-genotoxic carcinogens, phenobarbital and clofibrate, on the relationship between reactive oxygen species, antioxidant enzyme expression and apoptosis

Phenobarbital and clofibrate, two non-genotoxic carcinogens, have been investigated regarding the relationship between reactive oxygen species, antioxidant enzyme expression and apoptosis in primary cultures of rat hepatocytes. Low toxicity concentrations, 200 and 100 microg/ml for phenobarbital and clofibrate respectively, were used to examine their effect on spontaneous or transforming growth factor beta1 (TGFbeta1)-induced apoptosis and on the expression of antioxidant defence enzymes (superoxide dismutases and catalase). The increased incidence of apoptotic nuclei was visualized in TGFbeta1-treated cultures with the fluorescent dye Hoechst 33258 and was quantified under all experimental conditions by measurement of the hypodiploid peak in DNA histograms obtained by flow cytometry. Both substances, when added separately to hepatocyte cultures and incubated for 24 and 48 h, significantly diminished spontaneous apoptosis and exhibited a slight suppression of TGFbeta1-induced apoptosis. Endogenous peroxide production by hepatocytes increased with TGFbeta1, phenobarbital or clofibrate and the increase was greater with phenobarbital and in the presence of TGFbeta1 with both drugs. Gene expression of catalase and Mn- and Cu,Zn superoxide dismutases (SOD) was evaluated by northern blot analysis of hepatocytes incubated in the presence of phenobarbital or clofibrate with or without TGFbeta1 and the following differences were detected: phenobarbital induced a significant decrease in both dismutases (to 56%, P < 0.05, and 55%, P < 0.05, for Mn- and Cu,Zn-SOD respectively) and a 2-fold increase (P < 0.01) in catalase; clofibrate induced a slight decrease in both SODs and a 4-fold increase (P < 0.05) in catalase; TGFbeta1 significantly decreased to 37% (P < 0.05) expression of catalase while not significantly affecting expression of both SODs. We conclude that inhibition of spontaneous apoptosis induced by either phenobarbital or clofibrate is accompanied by increases in the endogenous levels of peroxides and by significant induction of catalase gene expression. Furthermore, the lack of effect of both compounds on TGFbeta1-induced apoptosis could be a consequence of the inability of these two compounds to counteract the depressing effect of TGFbeta1 on expression of catalase.      

Chemotherapy-induced amenorrhea: influence on disease-free survival and overall survival in receptor-positive premenopausal early breast cancer patients.

BACKGROUND: The aim of this study was to evaluate the influence of early chemotherapy-induced amenorrhea (CIA) on disease-free survival and overall survival in premenopausal patients with receptor-positive early breast cancer treated with adjuvant chemotherapy without any hormonotherapy. PATIENTS AND METHODS: Retrospectively, we reviewed data from 130 premenopausal patients with localized hormone-sensitive breast cancer. These patients were treated between 1985 and 1995 at the same institution. They all underwent a loco-regional treatment and adjuvant chemotherapy. Early CIA was defined as an amenorrhea arising during the first year following the beginning of chemotherapy. Predictors of early CIA were examined. The survival analyses were done using the Kaplan-Meier method and Cox analysis. RESULTS: Median follow-up was 9 years. Mean age was 42.9 +/- 5 years. Ninety-two per cent of patients had histologically-proven positive axillary nodes. Adjuvant chemotherapy contained no anthracycline in 63%. Early CIA occurred during or after adjuvant chemotherapy in 57% of the patients. It was definitive in 91%. In our study, age was the only CIA predictor in univariate analysis. Women who experienced early CIA tend to have a longer disease-free survival, but the difference was not significant. This trend was lost in multivariate analysis, most probably due to the small sample size. The overall survival was not different. CONCLUSION: Although not statistically significant, our results on a very selected population of patients suggest that a chemotherapy-induced amenorrhea might have its own therapeutic effect besides the cytotoxic action of chemotherapy.     

Traitement des carcinomes épidermoïdes localement évolués des voies aéro-digestives supérieures: place de la radio-chimiothérapie

Résumé: La radio-chimiothérapie concomitante est devenue le traitement de référence des carcinomes épidermoïdes localement évolués inopérables de la tête et du cou. L’association d’une chimiothérapie à une radiothérapie hyperfractionnée est également supérieure à une radiothérapie hyperfractionnée exclusive. Par ailleurs la radiochimiothérapie concomitante est actuellement le traitement postopératoire standard des patients à haut risque de récidive locorégionale. Le schéma optimal reste à déterminer. Le cisplatine est la molécule ayant fait la preuve d’une plus grande efficacité et la place de la polychimiothérapie n’est pas encore définie. La toxicité aiguë de ces protocoles nécessite des soins de support adaptés mais la toxicité tardive ne semble pas majorée. Des essais avec un long suivi et une évaluation de la qualité de vie sont nécessaires.Les cancers des voies aéro-digestives supérieures     

Rendu–Osler–Weber syndrome presenting with pulmonary arteriovenous fistula

A pulmonary arteriovenous fistula is an abnormal connection between pulmonary arteries and veins. Patients with Rendu–Osler–Weber syndrome may present with this vascular malformation, which is a typical finding of the disease. Approximately 5–15% of Rendu–Osler–Weber syndrome patients have pulmonary arteriovenous malformations (AVM) and there is usually a family history of AVM in these patients. The malformations are usually located in the lower lobes. In this paper, I describe a 49‐year‐old male patient with dyspnoea, cough, haemoptysis and epistaxis. Physical examination showed nasal telangiectasias, cyanosis of the lips and nails, and a systolic bruit over the left lung. Chest X‐ray revealed a 5‐cm mass in the left lower lobe and after magnetic resonance examination, together with 3‐D magnetic resonance angiography, it was demonstrated to be a pulmonary arteriovenous fistula. The history of a niece with a similiar history of suspected pulmonary arteriovenous fistula led me to consider the possibility of Rendu–Osler–Weber syndrome presenting with a pulmonary arteriovenous fistula.     

Wait Times and Survival in Lung Cancer Patients across the Province of Quebec,Canada

Lung cancer is the leading cause of cancer death worldwide, with a five-year survival of 22% in Canada. Guidelines recommend rapid evaluation of patients with suspected lung cancer, but the impact on survival remains unclear. We reviewed medical records of all patients with newly diagnosed lung cancer in four hospital networks across the province of Quebec, Canada, between 1 February and 30 April 2017. Patients were followed for 3 years. Wait times for diagnosis and treatment were collected, and survival analysis using a Cox regression model was conducted. We included 1309 patients, of whom 39% had stage IV non-small cell lung cancer (NSCLC). Median wait times were, in general, significantly shorter in patients with stage III–IV NSCLC or SCLC. Surgery was associated with delays compared to other types of treatments. Median survival was 12.9 (11.1–15.7) months. The multivariate survival model included age, female sex, performance status, histology and stage, treatment, and the time interval between diagnosis and treatment. Longer wait times had a slightly protective to neutral effect on survival, but this was not significant in the stage I–II NSCLC subgroup. Wait times for the diagnosis and treatment of lung cancer were generally within targets. The shorter wait times observed for advanced NSCLC and SCLC might indicate a tendency for clinicians to act quicker on sicker patients. This study did not demonstrate the detrimental effect of longer wait times on survival.     

Role of nuclear receptors and their ligands in human trophoblast invasion

Human implantation involves a major invasion of the uterine wall and complete remodelling of uterine arteries by extravillous cytotrophoblasts (EVCT). Abnormality in these early steps of placental development leads to poor placentation, fetal growth defects and is often associated with preeclampsia, a major and frequent complication of human pregnancy. To study the mechanisms that control trophoblast invasion during early placental development and provide new insight in the understanding of preeclampsia, we have developed in vitro models of human invasive trophoblasts. We have shown that activation of the ligand-activated nuclear receptor PPARgamma with synthetic (rosiglitazone) or natural (15deoxyPGJ(2)) agonists inhibits the trophoblastic invasion process. Analysis of PPARgamma-target genes revealed that placental growth hormone and the protease PAPP-A might be involved in the PPARgamma-mediated effect in an autocrine manner. We next investigated PPARgamma ligands at the materno-fetal interface and have shown that oxidized LDLs are present in EVCT in situ and decrease trophoblast invasion in vitro. Analysis of oxidized LDLs revealed that they contain potent PPARgamma agonists such as eicosanoids and also high levels of oxysterols, which are specific ligands for the liver X receptor (LXR). The isoform beta of LXR was found in EVCT in situ, and activation of LXRbeta with synthetic or natural ligands inhibits trophoblast invasion in vitro. Together, our data underscore a major role for PPARgamma and LXRbeta in the control of human trophoblast invasion and suggest that excess ligands such as oxidized LDLs at the implantation site might contribute to the development of preeclampsia.     

Link Between Carbapenemase-Producing Enterobacteria Carriage and Cross-Border Exchanges: Eight-Year Surveillance in a Large French Multihospitals Institution

Assistance Publique-H?pitaux de Paris launched a specific strategy to survey and control the spread of emerging multidrug-resistant bacteria such as carbapenemase-producing Enterobacteria (CPE). Among the 63 CPE events that occurred between 2004 and 2011, 87% involved patients with a link with cross-border exchanges, justifying the recommendation to screen and isolate such patients.