Cisplatin benefit is predicted by immunohistochemical analysis of DNA repair proteins in squamous cell carcinoma but not adenocarcinoma: theranostic modeling by NSCLC constituent histological subclasses

BACKGROUND

Most non-small-cell lung cancer (NSCLC) patients receive cisplatin-based chemotherapy though clinical response is restricted to a subset of patients. DNA repair protein levels are possible surrogates for cisplatin-induced DNA adduct (and subsequent cell death) repair efficiency and thus molecular determinants of therapeutic efficacy. The International Adjuvant Lung Trial (IALT)-Bio study previously suggested ERCC1 and MSH2 as predictive of cisplatin-based therapeutic benefit.

PATIENTS AND METHODS

DNA repair protein expression (XPF, BRCA1, ERCC1, MSH2, p53, PARP1, and ATM) was assessed by immunohistochemistry on a large subset of patients (N = 769) from the IALT trial. Tissue Microarray slides were digitally scanned and signal quantified by user-defined macros. Statistical analyses (univariate and multivariate) of 5-year disease-free survival (DFS) and 5-year overall survival used binary cut-offs (H score low/high expression).

RESULTS

In patients with squamous cell carcinoma (SCC), ATM, p53, PARP1, ERCC1, and MSH2 displayed significant (borderline) predictive values, mainly on DFS with chemotherapy efficacy limited to low marker levels. Adenocarcinoma (ADC) results were not significant. BRCA1 and XPF were not significant for predictive modeling in either SCC or ADCs.

CONCLUSION

Here predictive utility of DNA repair enzymes co-segregates with SCC histology, focusing their predictive value to this histological subclass of NSCLC. Distinct mechanisms of chemotherapeutic response or resistance might exist among histological subclasses of solid tumors.

Gemcitabine and oxaliplatin (GEMOX) alone or in combination with cetuximab as first-line treatment for advanced biliary cancer: Final analysis of a randomized phase II trial (BINGO)

4032

Background: Gemcitabine-platinum chemotherapy (CTx) regimens are widely accepted as first-line standard of care for patients (pts) with advanced biliary cancers (ABC). EGFR overexpression has been observed in ABC, suggesting that the combination with anti-EGFR monoclonal antibodies may be appropriate. Methods: Patients with ABC, WHO performance status (PS) 0-1, and without prior palliative CTx were eligible for this international, open-label, two-stage, non-comparative, randomized phase II trial. Patients received GEMOX (gemcitabine, 1 g/m² [10 mg/m²/min] at day [D]1 + oxaliplatin, 100 mg/m² at D2, arm A) or GEMOX + cetuximab (500 mg/m² at D1 or 2, arm B), every 2 weeks. The primary endpoint was crude 4-month progression-free survival (PFS) rate (H0, <40%; H1, ≥60%; planned sample size, 100 pts, increased to 150 pts by amendment to allow subgroup analyses). Secondary endpoints were objective response rate (ORR), disease control rate (DCR), PFS, overall survival (OS), and toxicity (NCI-CTC v3.0). Exploratory endpoints included early metabolic response as assessed by PET at 1 month, and tumor KRAS mutational analysis. Results: From Oct. 2007 to Dec. 2009, we enrolled 150 pts (median age, 62 years; male, 57%; metastatic, 79%; cholangiocarcinoma, 84%; median follow-up, 30 months) (Table). Conclusions: GEMOX-cetuximab regimen was well tolerated and met its primary endpoint (4-month PFS ≥60%). However, median PFS and OS were similar in both arms. Exploratory analyses (e.g., KRAS tumor status) are underway to identify pt subgroups deriving benefit from the addition of cetuximab to CTx. [Table: see text]

ALK amplification and crizotinib sensitivity in non-small cell lung cancer cell lines and patients report

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Background: ALK high copy number (HCN) seems to be a frequent event, described in 13-17% of Non-small cell lung cancer (NSCLC). The goal of this study was to describe ALK genomic aberrations on NSCLC patients and cell lines, to explore the ALK HCN response to crizotinib through in vitro assays and to report three patients case. Methods: 191 Paraffin embedded specimens from advanced NSCLC patients and 27 NSCLC cancer cell lines were screened for ALK copy number by fluorescent in situ hybridization (FISH). Crizotinib sensitivity was evaluated in 9 cell lines through WST1 assays and clonogenic tests. Three patients exhibiting ALK HCN were assessed for response to crizotinib. Results: EML4-ALK translocation was present in 22 pts (11.5%). 21 pts (11%) exhibited over 6 copies of ALK. 6 (22%) cell lines displayed more than 5 copies of ALK, 19 (70%) presented a gain of 3 or 4 ALK copy number, only one cell line exhibited normal ALK copies and one harbored EML4-ALK translocation. FISH with CEP2 revealed a polysomy of chromosome 2 in cases with ALK HCN.Out of the 9 cell lines tested, 4 ALK HCN cell lines (H661, A427, BEN, H1299) exhibited increased sensitivity for crizotinib vs. 3 low ALK copy number (LCN) cell lines (H1975, H1651, H1650) with a low sensitivity. Median IC50 with crizotinib values was1750 nM [300-2800nM] in ALK HCN cell lines vs 4500 nM [800-8000nM] in ALK LCN cell lines, p=0.35. 3 patients with ALK HCN tumor received crizotinib ( in 4th , 5th and 6th -line therapy) for 2, 3 and 5 months with stable disease as best response and clinical benefit in 2 pts. Conclusions: ALK HCN may predict sensitivity to crizotinib. A clinical study is planned in ALK HCN pts.

Prenatal diagnosis and evaluation of defect length in esophageal atresia using direct and indirect (tracheal print) signs

The prenatal diagnosis of esophageal atresia is challenging. The length of the defect of the esophageal atretic portion is one of the parameters affecting outcome and prenatal evaluation of this length has not, to our knowledge, been described previously. We report on seven fetuses assessed prospectively which were suspected to have esophageal atresia. Targeted ultrasound examination of both fetal cervical and thoracic structures was performed in each case in order to assess prenatally the atretic portion. The length of the defect was assessed both directly, by visualizing the interruption of the hyperechoic lines representing the walls of the esophagus in a mid-sagittal view (n = 4), and indirectly, by means of the 'tracheal print' (n = 5). Both methods were used in three cases. Prenatal results were compared with postnatal or postmortem findings. The prenatal diagnosis of esophageal atresia was made correctly in six of the seven cases and in all of these there was concordance between prenatal and postnatal estimates of the esophageal defect lengths. Direct or indirect sonographic assessment of the esophagus in cases of suspected prenatal esophageal atresia improves the specificity of its diagnosis and aids prenatal evaluation.

Factors associated with partial and complete regression of fetal lung lesions

OBJECTIVE

A decrease in the volume of congenital pulmonary malformations (CPM) can be observed on prenatal ultrasonography, but the underlying mechanism for this phenomenon is unknown. Our objective was to identify factors associated with the prenatal reduction in size of cystic and/or hyperechoic lung lesions.

METHODS

This was a retrospective study of cases with a prenatal diagnosis of hyperechoic and/or cystic lung lesion. The extent of reduction in lesion size was calculated from ultrasound measurements. Clinical, ultrasound, radiological and histological data were tested for their relationship with prenatal CPM reduction.

RESULTS

In a 4-year period, 36 patients were referred with a cystic and/or hyperechoic fetal lung lesion diagnosed at a mean gestational age of 23.4 weeks. The lesions were cystic in 16 cases (44%), hyperechoic in 12 (33%) and both in eight (22%). The malformation was no longer visible before birth (apparent disappearance) in nine cases (25%), shrank by 18-90% in 15 (42%) and did not reduce in 12 (33%). Findings on postnatal computed tomography were always abnormal. Isolated hyperechoic lesions were significantly more likely to shrink in utero. The mean reductions were 79%, 35% and 19%, for isolated hyperechoic, cystic and mixed lesions, respectively (P=0.001). Only 8% of hyperechoic lesions demonstrated no volume reduction, as compared to 50% and 42% of cystic and mixed lesions, respectively (P=0.03). Greater gestational age at birth was also associated with a decrease in the incidence of malformations (P=0.02). In cases that underwent surgery, hyperechoic lesions were linked to a variety of pathological diagnoses, whereas cystic lesions were all described histologically as congenital cystic adenomatoid malformations.

CONCLUSIONS

Prenatal size reduction of fetal lung malformations is associated with isolated hyperechogenicity and greater gestational age at birth. This might result from the resumption of normal lung development after local disruption of lung growth.

Prenatal prediction of neonatal morbidity in survivors with congenital diaphragmatic hernia: a multicenter study

OBJECTIVES

To investigate the value of the observed to expected fetal lung area to head circumference ratio (o/e LHR) and liver position in the prediction of neonatal morbidity in survivors with congenital diaphragmatic hernia (CDH).

METHODS

Neonatal morbidity was recorded in 100 consecutive cases with isolated CDH diagnosed in fetal medicine units, which were expectantly managed in the prenatal period, were delivered after 30 weeks and survived until discharge from hospital. Regression analysis was used to identify the significant predictors of morbidity, including prenatal and immediate neonatal findings.

RESULTS

The o/e LHR provided significant prediction of the need for prosthetic patch repair, duration of assisted ventilation, need for supplemental oxygen at 28 days, and incidence of feeding problems. An additional independent prenatal predictor of the need for patch repair was the presence of fetal liver in the chest.

CONCLUSIONS

In isolated CDH the prenatally assessed size of the contralateral lung is a significant predictor of the need for prosthetic patch repair, the functional consequences of impaired lung development and occurrence of feeding problems.

Emergency management and conservative surgery of ovarian torsion in children: a report of 40 cases

INTRODUCTION

The authors describe and discuss the clinical and therapeutic features of 40 ovarian torsions (OT) in children with its urgent treatment that has advanced in recent years.

MATERIALS AND METHODS

A retrospective study of 40 cases of OT in 38 children under 16 years of age, excluding adnexal torsions in neonates.

RESULTS

Abdominal and/or pelvic pain was the presenting symptom ; 8 of these children had pain between 2 to 9 months prior to surgery and 27/40 (67.5%) had associated vomiting. Before the procedure, ultrasound (US) diagnosed 29 ovarian lesions, related to 14 mature teratomas (MTE) and 10 cystadenomas (CA), one association of MTE and CA in the same ovary, 2 functional cysts and 2 malignant neoplasms. 19/40 torsions could benefit from conservative management. Eleven torsions occurred, 10/11 of these ovaries had an increased volume, and 5/11 had US evidence of small subcortical cysts. Three detorsions with incomplete removal of CA were followed by enlargement of the tumor and re-torsion in 2 of them. Five children had bilateral ovarian pathology which led to unilateral ovariectomy, while the other benefited from conservative treatment.

CONCLUSIONS

In any girl presenting with abdominal pain, the diagnosis of an ovarian torsion must be considered. US is performed emergently, but only surgery, most often a laparoscopic procedure, assures diagnosis. The treatment of the torsion is an emergency and must be as conservative as possible in order to preserve the ovarian function. Bilateral torsions are not unusual.

Collective oscillations of strongly correlated one-dimensional bosons on a lattice

We study the dipole oscillations of strongly correlated 1D bosons, in the hard-core limit, on a lattice, by an exact numerical approach. We show that far from the regime where a Mott insulator appears in the system, damping is always present and increases for larger initial displacements of the trap, causing dramatic changes in the momentum distribution, n(k). When a Mott insulator sets in the middle of the trap, the center of mass barely moves after an initial displacement, and n(k) remains very similar to the one in the ground state. We also study changes introduced by the damping in the natural orbital occupations, and the revival of the center-of-mass oscillations after long times.

Prebiotic effects of oligosaccharides on selected vaginal lactobacilli and pathogenic microorganisms

The purpose of this study was to select endogenous human vaginal lactobacilli strains on the basis of the main probiotic properties observed in the vaginal environment in order to use them for the evaluation of the potential prebiotic properties of oligosaccharides. From vaginal samples of 50 women with a normal flora, 17 lactobacilli strains were first isolated because of their high level of hydrogen peroxide production. Then six strains were selected mainly for their ability (i) to adhere to vaginal cells, (ii) to produce compounds in sufficient amount, such as lactic acid, having an inhibitory action on pathogens, and less importantly, (iii) to demonstrate arginine deiminase activity. These six strains were found to belong to three distinct species: Lactobacillus crispatus, L. jensenii and L. vaginalis. One strain of each species was chosen as a potential vaginal probiotic strain with regard to our criteria. These three strains were then used to evaluate the prebiotic properties of different oligosaccharide series: two fructooligosaccharide series (FOS Actilight and FOS Raftilose) and two glucooligosaccharide series varying by their osidic linkages (alpha-1,6/alpha-1,4 GOS and alpha-1,2/alpha-1,6/alpha-1,4 GOS). The test was based on the ability of the oligosaccharides to promote the growth of the three beneficial strains selected but not of pathogenic microorganisms often encountered in urogenital infections such as Candida albicans, Escherichia coli and Gardnerella vaginalis. Oligosaccharide hydrolysis was followed by HPLC analysis. This revealed that two oligosaccharide series (FOS Actilight DP3 and all alpha-1,6/alpha-1,4 GOS DP > or = 4) were used only by the lactobacilli strains, the pathogenic microorganisms being unable to metabolise them. The selected lactobacilli and oligosaccharides are good candidates for incorporation in a formula to prevent vaginal infections.

Phase separation in the two-dimensional bosonic Hubbard model with ring exchange

We show that soft-core bosons in two dimensions with a ring exchange term exhibit a tendency for phase separation. This observation suggests that the thermodynamic stability of normal Bose liquid phases driven by ring exchange should be carefully examined.

Mott domains of bosons confined on optical lattices

In the absence of a confining potential, the boson-Hubbard model exhibits a superfluid to Mott insulator quantum phase transition at commensurate fillings and strong coupling. We use quantum Monte Carlo simulations to study the ground state of the one-dimensional bosonic Hubbard model in a trap. Some, but not all, aspects of the Mott insulating phase persist. Mott behavior occurs for a continuous range of incommensurate fillings, very different from the unconfined case, and the establishment of the Mott phase does not proceed via a traditional quantum phase transition. These results have important implications for interpreting experiments on ultracold atoms on optical lattices.

[Protective role of the Doderleïn flora]

The vaginal flora of a healthy woman is composed of the Doderleïn bacilli (different species of lactobacilli) forming a biofilm on the mucosa. These bacteria have a beneficial effect by inhibiting growth, adhesion or spread of other microorganisms. Different mechanisms are recognized, including secretion of organic acids, production of antimicrobial substances (hydrogen peroxide, bacteriocins and biosurfactants), competition for nutrients (arginine deiminase), competition for receptors (adhesion on the epithelium), steric exclusion (biosurfactants, adhesion on the epithelium or on the fibronectin) and co-aggregation. This ecological balance can be disturbed by drugs (antibiotics and spermicides) or by local devices. A new therapeutic approach has been proposed to restore a normal flora: the use of probiotics by the association of different lactobacilli with combined antimicrobial activity.

Restoration of vision IV: role of compensatory soma swelling of surviving retinal ganglion cells in recovery of vision after optic nerve crush

PURPOSE

Diffuse axonal injury following partial optic nerve crush (ONC) leads to severe visual deficits from which rats can partially recover within 2-3 weeks. To evaluate tbc role of surviving retinal ganglion cells (RGCS) in recovery, we have observed their morphology repeatedly in vivo with ICON-microscopy and correlated cell size changes with recovery of vision which we observed in parallel in the same animals.

METHODS

After rats had learned a visual contrast discrimination task using an automated, computer-based test, RGCs were labeled retrogradely with fluorescent beads. Animals then received either no lesion, a complete axotomy or bilateral mild, moderate or severe ONC. Before surgery and for 40 days post-operatively, ROC number and soma size was repeatedly quantified every five days with tbc in vivo confocal neuroimaging method (Sabel et al., Nature med. 3, 1997, p. 244). In parallel, visual function was quantified with the contrast-discrimination task.

RESULTS

After ONC about 70 % of the ROCs died after having undergone a fast and massive soma swelling. The extent of cell death was independent of crush severity. RGCs surviving the injury did not change their body size over time in the severe group and these animals also did not recover their vision. In contrast, after a mild or moderate crush, about half of the surviving RGCs experienced a slow and moderate, "compensatory" cell soma swelling and the rats showed partial recovery of vision. Both the number of RGCs showing such compensatory soma swelling and the extent of the swelling correlated highly (r = 0.96) with recovery of contrast discrimination performance at post-operative days 23 and 38.

CONCLUSIONS

Depending en the time course and extent, soma swelling after neurotrauma may be associated either with cell death or recovery of function. Because of the very high correlation between extent of recovery and amount of soma swelling, moderate soma swelling contributes in a prominent way to recovery of vision. We believe that these cells provide an important structural substrate for neuronal tissue repair and therefore term these cells "compensatory neurons".

Calcineurin Co-regulates contractile and metabolic components of slow muscle phenotype

Activation of the transcription factor nuclear factor of activated T cells by the calcium-sensitive serine/threonine phosphatase calcineurin has been proposed as one of the molecular mechanisms by which motor nerve activity establishes the slow muscle phenotype. To investigate whether the calcineurin pathway can regulate the large spectrum of slow muscle characteristics in vivo, we treated rats for three weeks with cyclosporin A (an inhibitor of calcineurin). In soleus (slow muscle), but not in plantaris (fast muscle), the proportion of slow myosin heavy chain (MHC-1) and slow sarcoplasmic reticulum ATPase (SERCA2a) was decreased, whereas that of fast MHC (MHC-2A) and fast SERCA1 increased, indicating a slow to fast contractile phenotype transition. Cytosolic isoforms of creatine kinase and lactate dehydrogenase (most abundant in fast fibers), as well as mitochondrial creatine kinase and citrate synthase activities (elevated in fast/oxidative fibers) were dose dependently increased by cyclosporin A treatment in soleus muscle, with no change in plantaris. Calcineurin catalytic subunit was more abundant in soleus muscle fibers compared with plantaris. Taken together these results suggest that the calcineurin pathway co-regulates a set of multigenic protein families involved in the transition between slow oxidative (type I) to fast oxidative (type IIa) phenotype in soleus muscle.

Avian reticuloendotheliosis virus strain A and spleen necrosis virus do not infect human cells

Spleen necrosis virus (SNV) and Reticuloendotheliosis virus strain A (REV-A) belong to the family of reticuloendotheliosis viruses and are 90% sequence related. SNV-derived retroviral vectors produced by the REV-A-based D17.2G packaging cell line were shown to infect human cells (H.-M. Koo, A. M. C. Brown, Y. Ron, and J. P. Dougherty, J. Virol. 65:4769-4776, 1991), while similar vectors produced by another SNV-based packaging cell line, DSH134G, are not infectious in human cells (reviewed by R. Dornburg, Gene Ther. 2:301-310, 1995). Here we describe a careful reevaluation of the infectivity of vectors produced from the most commonly used REV-A- or SNV-based packaging cells obtained from various sources with, among them, one batch of D17.2G packaging cells obtained from the American Type Culture Collection. None of these packaging cells produced vectors able to infect human cells. Thus, contrary to previously published data, we conclude that REV-based vectors are not infectious in human cells.

Restoration of vision III: soma swelling dynamics predicts neuronal death or survival after optic nerve crush in vivo

Predicting neuron death or survival after axonal injury is important in neurotrauma research. We now used in vivo confocal neuroimaging microscopy to repeatedly visualize retinal ganglion cells after optic nerve crush and studied their morphological alterations and ultimate fate. An intracollicular injection of a retrograde fluorescent tracer was made before or after optic nerve crush. Retinal ganglion cell sizes were then determined at different time points up to post-surgery day 75. Cell death was inevitable when soma swelling was fast and massive (86% above baseline or higher), but when it was slower and moderate (32% above baseline) long-term neuron survival could be predicted with high accuracy as early as post-operative day 5. Moderate swelling continued until day 15 (64%) and after about 3 weeks these cells started shrinking again, as a sign of recovery. We propose that moderate soma swelling is an adaptive rather than pathogenic post-traumatic reaction to axonal injury.

Early detection of liposome brain localization in rat experimental allergic encephalomyelitis

Blood-brain barrier (BBB) permeability increases prior to the development of clinical signs in early-stage multiple sclerosis (MS). Detection of subtle changes would thus be helpful for diagnostic purposes and rapid therapeutic decisions before new episodes. Since multiple sclerosis and experimental allergic encephalomyelitis (EAE) have numerous common features, in particular BBB-permeability characteristics, and since we have previously shown that BBB localization is disturbed by tumors, embolism, and mannitol injection, we investigated BBB-liposome permeability in an EAE rat model. Twenty young male Lewis rats received a single intradermal inoculation of guinea-pig spinal cord. The effect of the Freund's adjuvant and spinal cord alone on brain permeability were also assessed. In order to compare solution permeability and liposome localization, radioactive liposomes and, 1 h later, 99mTc-DTPA were injected intravenously. Scintigraphic acquisitions were obtained to follow the biodistribution of radioactivity in the whole body. Each rat was subjected to a first examination before inoculation and then every two days until completion and may be considered as its own control. EAE induced a previously unreported increase in global-body permeability, probably due to inflammation. Liposome brain localization and brain/heart ratio were significantly different between normal animals and those with early-stage EAE (before appearance of clinical signs) and distinguished between different disease stages in clinically patent EAE. The index of disease progression was modified earlier than with 99mTc-DTPA injection. One explanation may be particle pick-up by circulating macrophages, which cross the BBB during this pathology. For clinical applications, experiments must be confirmed on models more reliable for human multiple sclerosis.

Macaque lymphocytes transduced by a constitutively expressed interferon beta gene display an enhanced resistance to SIVmac251 infection

We are developing a method of gene therapy of HIV infection based on the low constitutive expression of an interferon beta (IFN-beta) gene in HIV target cells. Herein we report the first step in the development of a relevant animal model, provided by the macaque (Macaca fascicularis) infected with a pathogenic SIVmac251 isolate. To avoid the possibility of in vivo rejection of macaque lymphocytes expressing Hu IFN-beta, we have PCR-amplified and sequenced the Ma IFN-beta-coding sequence, and placed it under the control of a PstI-NruI 0.6-kb fragment of the murine H-2Kb gene promoter in the MFG-K(b)MaIFNbeta retroviral vector. Lymphocytic CEMX174 cells, transduced by coculture on packaging cells with this construct, harbored a mean of 0.07 to 1.2 copies of the IFN-beta transgene per cell, and were characterized by an IFN production ranging from 75 to 750 units per 5 x 10(5) cells per 3 days. The IFN-beta-transduced populations displayed an enhanced resistance against the pathogenic SIVmac251 isolate. Control experiments showed that the enhanced resistance could not be ascribed to the Ma IFN-beta released during the 3 days of coculture by the packaging cells, or to the mere transduction with a retroviral vector. Macaque lymphocytes transduced by the MFG-K(b)MaIFNbeta retroviral vector by coculture on packaging cells, acquired a mean number of IFN-beta transgene copies per cell ranging from 0.03 to 0.1. Such transduction led to the release of IFN-beta into the culture medium, ranging from 10 to 20 units per 5 x 10(5) cells per 3 days. This increased the anti-SIV resistance of the lymphocytes, as demonstrated by a decreased p27 antigen release into the culture medium, without affecting lymphocyte proliferation.

NMR investigation of experimental chemical induced brain tumors in rats, potential of a superparamagnetic contrast agent (MD3) to improve diagnosis

The different steps of development of chemically induced brain tumors were investigated in rats by MRI using a superparamagnetic contrast agent, magnetite-dextran nanoparticles (MD3). Sprague Dawley strain pregnant female rats were injected intravenously with ethylnitrosourea solution at the end of pregnancy. Offspring whelped by the inoculated mother were followed. MRI examinations were performed at 0.5 T. MD3 nanoparticles were injected intravenously at a dose of 5 mg Fe kg(-1) body weight 30 min before rat sacrifice. After sacrifice, histological slices were stained with hematoxylin-eosin. Relaxation times were measured at 40 MHz and 37 degrees C. MD3 nanoparticles act differently according to the step of the tumor development. Before tumor appearance, at a step characterized by the presence of abnormal cell clusters, relaxation time T2 increased significantly. The T2-weighted image showed a small increase in signal intensity in the lesion. Image contrast was improved by MD3 nanoparticles injection because of the decrease in healthy tissue signal intensity. The T1-weighted image did not provide any additional information. In presence of a minute tumor, relaxation times decreased in tumor but increased in surrounding tissue. The T1-weighted image showed a hypersignal on the border of an hyposignal. T2-weighted image showed a hypersignal in the same area. Signal intensity was not modified after MD3 nanoparticles injection. When new vascular capillaries developed in the tumor, MD3 nanoparticles cross into the cerebral parenchyma. Transmission electron microscopy showed magnetite crystals in this specific area on cytoplasm vesicles of glial cells and in tumor-specific membrane arrangements. On T2-weighted image, the hypersignal consisted of a well defined part and a second more fuzzy part, its signal being extinguished after MD3 nanoparticles injection. Necrotic areas and edema can be discriminated. The use of such a superparamagnetic contrast agent would be helpful in early detection of tumor development and in improving distinction of tumor mass from its vascular environment in patients.

Glial tumoral proliferation induces changes in the state and physical properties of water during ENU-induction of brain tumors in rats

Modifications of water state were analyzed during ethylnitrosourea-induction of brain tumor in rats. Four different steps were identified in the cancerization process according to NMR and histological findings. Two analogies were observed in the pattern of bound' water at decreasing temperatures: first the pattern was similar in tumor area and white matter, second the pattern was similar in the same area of normal brain tissue and cortical gray matter. This phenomenon, which corroborates previous reports on liver cancerization, points out that pathological proliferation of glial cells, and their progressive organization into multiple layers, is accompanied by a transformation of water properties at the cellular level.

Investigation of blood-brain barrier permeability to magnetite-dextran nanoparticles (MD3) after osmotic disruption in rats

The permeability of experimentally disrupted blood-brain barrier (BBB) to superparamagnetic nanoparticles (MD3) was studied in rats. BBB opening was induced by intracarotid injection of mannitol. One hundred eighty rats were used for the study. Rats were examined at two time points, 30 minutes and 12 hours after intracarotid mannitol injection. Different preparations intravenously injected 30 minutes before rat sacrifice were used for characterization of BBB disruption. BBB integrity was determined with 99mTc-diethylenetriamine pentaacetic acid (DTPA) and 99mTc-albumin. Iron oxide-glucose particles (12-nm mean diameter), 99mTc-labeled lecithin-cholesterol liposomes of three different sizes (50, 100, and 200 nm), and polyethylene glycol (PEG)-coated 99mTc liposomes (50 nm) were used for investigations of the dependence of BBB permeability on particle system size or surface. Magnetite-dextran nanoparticles (MD3) were evaluated as superparamagnetic contrast agent to monitor with magnetic resonance imaging (MRI) the BBB breakdown. In vitro T1 and T2 relaxation times of the brain tissue were measured at 40 MHz and 37 degrees C, and T2-weighted MR images were acquired at 0.5 T. After intracarotid mannitol infusion, as expected, the BBB breakdown was immediate and temporary as judged by soluble molecule diffusion. MD3 nanoparticles crossed the BBB 12 hours after intravenous mannitol injection, at a time when brain permeability for molecules or small particles returns to normal. Magnetite crystals were found in cytoplasmic vesicles of glial cells. On MRI, signal intensity decreased after injection of MD3, even 12 hours after mannitol injection. This particularity could be useful in the study of focal pathological lesions accompanied by BBB permeability modifications. In such conditions, superparamagnetic particle contrast agents could be caught by the BBB, allowing the observation of impaired BBB areas without detectable cellular lesions.

Developmental and nutritional changes of ob and PPAR gamma 2 gene expression in rat white adipose tissue

The ob gene encodes leptin, a hormone which induces satiety and increases energy expenditure. The peroxisome proliferator-activated receptor gamma 2 isoform (PPAR gamma 2) gene encodes a transcription factor which controls adipocyte differentiation and expression of fat-specific genes. We have studied the regulation of these two genes in white adipose tissue (WAT) during the suckling-weaning transition. Suckling rats ingest a high-fat diet (milk). Fat-pad weight barely varied during the last week of suckling. ob mRNA levels, which were very low in 15-day-old rats, rose approximately 6-fold until weaning at 21 days. When the rats were weaned on to a standard (high-carbohydrate) laboratory chow, epididymal WAT enlarged approximately 7-fold, and ob mRNA kept increasing progressively and doubled between 21 and 30 days. This evolution contrasted with that of fatty acid synthase (FAS) mRNA, which increased sharply, but only after weaning. To distinguish between the influence of developmental and nutritional factors on ob expression, a group of rats was weaned on to a high-fat diet. This prevented the rise in glycaemia and insulinaemia and the decrease in plasma non-esterified fatty acids which otherwise occurred at weaning. This also resulted in a slight (10-15%) decrease in food intake and body weight gain. Under this high-fat diet, the rise of ob mRNA in WAT was augmented (3.7-fold in 30- versus 21-day-old pups), whereas the normal rise in FAS mRNA levels was attenuated. Fat-pad weights and adipocyte cell size and number were roughly similar in high-carbohydrate- and high-fat-weaned pups. mRNA levels of PPAR gamma 2, like those of ob, were low in the WAT of 15-day-old suckling pups, doubled at 21 days, and reached a maximum as soon as 23 days. This evolution further differed from that of ob mRNA in not being influenced by diet composition. In conclusion, ob expression markedly increases during the suckling-weaning transition, and this effect is accentuated by a high-fat diet. Qualitative nutritional changes in ob mRNA were correlated with neither acute changes in adipose-tissue mass, nor cell size/number, nor variations in insulinaemia. PPAR gamma 2 also increased during suckling, but rapidly reached a plateau after weaning and no longer changed thereafter. Unlike ob, PPAR gamma 2 was not influenced by the diet composition.

[Development of an anti-HIV gene therapy based on the antiviral properties of beta interferon]

The aim of our work is to explore the use of IFN-beta for gene therapy in the HIV-infection. Transduction of various HIV target cells with a retroviral vector that carries the Hu-IFN-beta coding sequence under constitutive low expression control, confers resistance to HIV without affecting cell replication or function. After transduction, lymphocytes from HIV-infected patients develop resistance to the endogenous virus, provided the cells are derived from individuals with a CD4 cell count higher than 200 per mm3.

Extracellular matrix components in intestinal development

Intestinal morphogenesis and differentiation are dependent on heterotypic cell interactions between embryonic epithelial cells (endoderm) and stromal cells (mesenchyme). Extracellular matrix molecules represent attractive candidates for regulators of these interactions. The structural and functional diversity of the extracellular matrix as intestinal development proceeds is demonstrated by 1) spatio-temporal specific expression of the classically described constituents, 2) the finding of laminin and collagen IV variants, 3) changes in the ratio of individual constituent chains, and 4) a stage-specific regulation of basement membrane molecule production, in particular by glucocorticoids. The orientation/assembly of these extracellular matrix molecules could direct precise cellular functions through interactions via integrin molecules. The involvement of extracellular matrix, and in particular basement membrane molecules in heterotypic cell interactions leading to epithelial cell differentiation, has been highlighted by the use of experimental models such as cocultures, hybrid intestines and antisense approaches. These models allowed us to conclude that a correct elaboration and assembly of the basement membrane, following close contacts between epithelial and fibroblastic cells, is necessary for the expression of differentiation markers such as digestive enzymes.

Antiviral activity of autocrine interferon-beta requires the presence of a functional interferon type I receptor

We and others have previously observed that the antiviral effects of autocrine interferon (IFN)-alpha/beta activity cannot be abolished by neutralizing antibodies, even when present to a large excess. This raises the possibility that the major part of autocrine activity is triggered intracellularly, possibly bypassing the transmembrane IFN-alpha/beta receptor. To examine this possibility, cells derived from IFN-alpha/beta Ro/o knockout mice lacking a functional IFN-alpha/beta receptor were stably transformed with pHMB-KbMuIFN beta or pMFG-MuIFN beta plasmids encoding a constitutively expressed murine IFN-beta gene. Four different clones were isolated and examined for resistance to a retrovirus, MFG-LacZ, and to Semliki Forest virus. Despite the production of autocrine IFN-beta at levels inducing high antiviral resistance in control cells, none of the clones displayed antiviral resistance. Thus, despite its failure to be neutralized by potent antiserum, the antiviral activity of autocrine IFN-beta takes place via the transmembrane IFN-alpha/beta receptor, and no additional pathway is involved.

Stable antiviral expression (SAVE) as an approach to somatic cell gene therapy directed against HIV infection

We are developing methods for somatic cell gene therapy directed against infection with human immunodeficiency virus by enhancing the antiviral resistance of target cells through the constitutive production of interferon-beta. Cells that have been transformed by plasmids or retroviral vectors carrying the human interferon-beta gene placed under the expression control of a murine H2Kb promoter fragment become resistant to HIV infection. Part of this enhanced resistance is due to inhibition of virus entry into the transformed cells, a hitherto unreported mechanism of interferon action.

Blocking of retroviral infection at a step prior to reverse transcription in cells transformed to constitutively express interferon beta

We are developing methods for somatic-cell gene therapy directed against infection with human immunodeficiency virus, by enhancing antiviral resistance of target cells through the constitutive production of autocrine interferon (IFN). Using the human IFN-beta coding sequence under the constitutive low-expression control of a 0.6-kb murine H-2Kb promoter-fragment, we have constructed a retroviral vector, HMB-KbHuIFN beta, and have transformed cells of the T98G human neuroblastoma line, the U-937 human promonocytic line, and the CEM human lymphocytic line. These human IFN-beta-transformed cell populations have acquired a low, constitutive production of human IFN, while replicating at a rate similar to that of untransformed cells and of cells transformed with the control vector carrying a human IFN-beta sequence encoding an inactive, mutated protein. In the three different cell populations tested, transformation with the HMB-KbHuIFN beta vector resulted in a 1.3-2.3 log10 reduction in the number of cells infected with a defective amphotropic MFG-LaZ retrovirus. A kinetic study of the fate of the MFG-LacZ retrovirus in the culture medium and intracellularly immediately after exposure of the cells to virus revealed a significant reduction of the appearance of intracellular virus in human IFN-beta-transformed cells. A similar effect was obtained by treating untransformed T98G, U-937, and CEM cells with exogenous human IFN-beta. The blocking effect of autocrine or exogenous human IFN-beta on viral entry was not limited to virus specific for the amphotropic receptor but was also obtained in murine IFN-beta-treated NIH 3T3 mouse fibroblasts infected with an ecotropic MFG-LacZ retrovirus. Infection of human IFN-beta-transformed CEM cells with human immunodeficiency virus type 1 gave comparable results. Immediately following exposure of the cells to human immunodeficiency virus, a kinetic study of the fate of the virus failed to reveal the appearance of intracellular virus and showed that the majority of the input virus remained in the extracellular medium. We conclude that low autocrine IFN-beta synthesis, or exposure of cells to exogenous IFN-beta, prevents virus from getting inside the cells, regardless of the virus receptor involved.

French multicentre trial comparing Casodex (ICI 176,334) monotherapy with castration plus nilutamide in metastatic prostate cancer: a preliminary report

This trial compares Casodex (ICI 176,334) monotherapy with the combination of castration (medical or surgical) plus nilutamide. The trial is now closed to entry, 270 patients having been recruited from 32 French centres. As it is too early to present efficacy data, only patient characteristics and interim tolerability data appear in this paper. In the combined treatment group, interstitial pneumonitis (4.5%) was observed, leading to withdrawal from the trial. Other adverse events leading to withdrawal included dyspnoea and ocular problems. There was also 1 case of hepatitis in this treatment group. In the Casodex treatment group, only 6 patients (as compared with 13 in the combined treatment group) withdrew from the trial because of adverse events. As expected with this group, the adverse events were mainly pharmacological effects of an anti-androgen as monotherapy. In the majority of patients, the effects of gynaecomastia and breast tenderness did not result in withdrawal.

Development of methods for somatic cell gene therapy directed against viral diseases, using retroviral vectors carrying the murine or human interferon-beta coding sequence: establishment of the antiviral state in human cells

We are developing methods for somatic cell gene therapy directed against chronic and fatal virus infections, such as acquired immunodeficiency (AIDS), by transforming cells with a constitutively expressed interferon (IFN) coding sequence. Previous work from our laboratory has shown that stable antiviral expression (SAVE) can be obtained in murine BALB/c 3T3 cells and human U937 cells transformed with plasmids carrying either the murine or the human IFN-beta coding sequence placed under the expression control of a 0.6-kb Xho II-Nru I promoter region of the murine H-2Kb major histocompatibility complex (MHC) gene (Macé et al., 1991; Seif et al., 1991). In the present paper, we report the construction of murine (Mu) and human (Hu) IFN-beta-expressing retroviral vectors (pMPZen-MuIFN beta, pHMB-KbMuIFN beta) and the problems encountered. Because of the murine origin of commonly used packaging cells and the species specificity of IFN, it was evident that placing the murine IFN-beta sequence under constitutive expression control could result in the production of Mu IFN in the murine packaging system, and thereby lead to decreased vector production and also to enhanced resistance of target cells. Using a packaging cell line that releases a beta-galactosidase-expressing vector, we show that, as expected, Mu IFN-alpha/beta decreases vector production of murine packaging cells and also inhibits the transformation of target NIH-3T3 cells with this vector, but the presence of anti-Mu IFN antibodies rescues the viral titer of the packaging cells and restores the sensitivity of target cells to virus transformation. However, the same antibody treatment is unable to rescue the viral titer of psi-2 packaging cells producing autocrine Mu IFN-beta encoded by the pMPZen-MuIFN beta and pHMB-KbMuIFN beta vectors. Because of the species specificity of IFN, this problem is circumvented with the pMFG-HuIFN beta vector carrying the human IFN-beta sequence. In spite of the production of Hu IFN, murine psi-CRIP packaging cells are able to release retroviral vectors expressing Hu IFN-beta, and these amphotropic vectors can transform human MRC-5 cells and confer to these cells an enhanced resistance to vesicular stomatitis virus (VSV) infection.

Enhanced in vitro cytotoxicity of 1,3-bis-(2-chloroethyl)-1-nitrosourea or buthionine sulfoximine combined with a reactive oxygen-generating enzyme immunotoxin

The glutathione inhibitor drugs, 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and buthionine sulfoximine (BSO), were tested in vitro in order to assess their cytotoxic effectiveness when combined with an enzyme immunotoxin (eIT) composed of a T-cell reactive monoclonal antibody (mAb) 097 coupled to the reactive oxygen-generating enzyme, glucose oxidase (GO) (EC 1.1.3.4). As targets of this eIT we used mature human T-cells or leukemia cells that expressed the 097 epitope. We found that treatment of the cells with subtoxic amounts of mixtures of both a drug and the 097 eIT markedly potentiated cytotoxicity compared to either drug or eIT alone.

Immunotoxins containing glucose oxidase and lactoperoxidase with tumoricidal properties: in vitro killing effectiveness in a mouse plasmacytoma cell model

We have tested the tumoricidal potency of enzyme immunotoxins constructed of antibodies conjugated to glucose oxidase and to lactoperoxidase. Murine plasmacytoma cells were targeted in vitro with the use of affinity-purified rabbit anti-plasmacytoma membrane antibodies (conjugated to glucose oxidase or lactoperoxidase) or rabbit serum raised against plasmacytoma microsome membranes followed by goat anti-rabbit immunoglobulin conjugates (to glucose oxidase or lactoperoxidase). Cytotoxicity was generated subsequently by incubation of the washed cells in a medium supplemented with glucose and sodium iodide, which were the substrates of these enzymes. This resulted in the presumed metabolic release of highly toxic reduced oxygen species and iodinated derivatives. Targeting of tumor cells with both conjugates, as opposed to one of them alone, produced a synergistic killing effect. The gain of specific versus unspecific cytotoxicity was upwards of 10,000-fold. The killing rates were elevated (t10 values less than 30 min) and linear over time. The resultant reduction in tumor cell viability was in the order of 5 to 6 logs after only 20 to 90 min of incubation in the glucose/NaI medium. Cytotoxicity was enhanced by the gamma-glutamyl cysteine synthetase inhibitor buthionine-S,R-sulfoximine and by the glutathione reductase inhibitor 1,3-bis(2-chloroethyl)-1-nitrosourea, while catalase was inhibitory. The results suggest that these enzyme immunotoxins may be suitable for the ex vivo purging of autologous bone marrow grafts.

An immunotoxin system intended for bone marrow purging composed of glucose oxidase and lactoperoxidase coupled to monoclonal antibody 097

The effectiveness of an antibody-enzyme immunotoxin (eIT) was investigated on human T cells. This enzyme immunotoxin contained glucose oxidase (GO) and lactoperoxidase (LPO) chemically coupled to the pan-leukocyte-specific mouse monoclonal antibody (MoAb) 097 (097-GO and 097-LPO). Human peripheral blood mononuclear cells or tumor cells were suspended in a mixture of 097-GO and 097-LPO for 30 min, and then for 2 h with glucose and NaI. The effectiveness of this eIT system was indicated by the almost complete reduction of T cell viability, as estimated by a phytohemagglutinin induced proliferation assay (99.4% +/- 0.31 depletion, mean +/- SEM of 15 experiments). The specificity of the cytotoxicity reaction was indicated by the lack of cytotoxicity of control irrelevant MoAb conjugates to T cells (1.9% +/- 4.17 of T cell depletion, eight experiments). The growth of human bone marrow myeloid progenitors (CFU-GM) was not affected by the conjugates even by increasing 100-fold the optimal cytotoxic dose. T cells were susceptible to the conjugates in the presence of up to 90% of erythrocytes. This eIT system may thus represent a new alternative immunospecific procedure for allograft and/or autograft purging, and appears to effectively replace complement-mediated methods of T cell depletion.

A new strain-specific cross-reactive idiotope with possible regulatory function expressed on BALB/c anti-alpha (1-3) dextran antibodies

We obtained a mAb, B5, defining a major crossreactive Id, the B5 Id, having an in vivo regulatory function. BALB/c mice immunized against the bacterial dextran Ag B1355S produce lambda 1-bearing anti-alpha (1-3) glucosidic linkage of dextran B1355S (DEX) antibodies. Of these antibodies 30% expressed the B5 Id determinant. As was observed for the IdX-Id, B5 idiotope expression was also linked to the BALB/c H chain allotype. The antibody family expressing the B5 Id included IdX+ as well as IdX- defined monoclonal anti-alpha (1-3) DEX antibodies. Injection into BALB/c mice of mAb B5 conjugated to keyhole limpet hemocyanin led to enhancement of serum anti-alpha (1-3) DEX antibody synthesis, and to a strong increase in B5+ Ig lacking dextran-binding activity. IdX+ serum Ig were also increased in these mice. Injection of this mAb into allotype congenic nonresponder C.B20 mice induced a significant serum lambda 1-bearing anti-alpha (1-3) dextran antibody response (5 to 50 micrograms/ml). However, in A/J nonresponder mice, a similar treatment induced only the dextran-nonbinding component, which reached high levels (approximately 7 mg/ml) in the sera of these mice. In the majority of these A/J mice, we detected a specific anti-(4-hydroxy-5-iodo-3-nitrophenyl)acetyl antibody response characterized by B5 Id-positive antibodies. This observation can be explained by an in vivo regulatory idiotope-mediated cross-regulation.

A new strain-specific cross-reactive idiotope with possible regulatory function expressed on BALB/c anti-alpha (1-3) dextran antibodies

We obtained a mAb, B5, defining a major crossreactive Id, the B5 Id, having an in vivo regulatory function. BALB/c mice immunized against the bacterial dextran Ag B1355S produce lambda 1-bearing anti-alpha (1-3) glucosidic linkage of dextran B1355S (DEX) antibodies. Of these antibodies 30% expressed the B5 Id determinant. As was observed for the IdX-Id, B5 idiotope expression was also linked to the BALB/c H chain allotype. The antibody family expressing the B5 Id included IdX+ as well as IdX- defined monoclonal anti-alpha (1-3) DEX antibodies. Injection into BALB/c mice of mAb B5 conjugated to keyhole limpet hemocyanin led to enhancement of serum anti-alpha (1-3) DEX antibody synthesis, and to a strong increase in B5+ Ig lacking dextran-binding activity. IdX+ serum Ig were also increased in these mice. Injection of this mAb into allotype congenic nonresponder C.B20 mice induced a significant serum lambda 1-bearing anti-alpha (1-3) dextran antibody response (5 to 50 micrograms/ml). However, in A/J nonresponder mice, a similar treatment induced only the dextran-nonbinding component, which reached high levels (approximately 7 mg/ml) in the sera of these mice. In the majority of these A/J mice, we detected a specific anti-(4-hydroxy-5-iodo-3-nitrophenyl)acetyl antibody response characterized by B5 Id-positive antibodies. This observation can be explained by an in vivo regulatory idiotope-mediated cross-regulation.

Monoclonal anti-alpha (1----3) dextran antibodies of Igha BALB/c and Ighb C.B20 mice display striking similarities

Allotype Ighb congenic C.B20 mice when immunized with dextran B1355S are unable to produce anti-alpha (1----3) dextran antibodies that express the VH-associated cross-reactive IdX idiotype. This intrastrain-specific idiotype is normally associated only with the anti-dextran response of Igha mice of which BALB/c is a prototype strain. In this study we have obtained monoclonal hybridoma antibodies specific for the alpha (1----3) glucosidic linkage of dextran from C.B20 mice that were presensitized with rabbit anti-IdX antibodies. These antibodies display the light chain isotype distribution, the H chain amino terminal sequence, share VH-associated IdX idiotypic determinants, and finally the similar fine specificity for dextrans observed for anti-alpha (1----3) dextran antibodies of BALB/c mice.