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ABSTRACT Neurofibromatosis type 1 ( NF1) affects about one in 3,500 people in all ethnic groups. Most NF1 patients have private loss-of-function mutations scattered along the NF1 gene. Here, we present an original NF1 investigation strategy and report a comprehensive mutation analysis of 565 unrelated patients from the NF- France Network. A NF1 mutation was identified in 546 of the 565 patients, giving a mutation detection rate of 97%. The combined c DNA/ DNA approach showed that a significant proportion of NF1 missense mutations (30%) were deleterious by affecting pre-m RNA splicing. Multiplex ligation-dependent probe amplification allowed the identification of restricted rearrangements that would have been missed if only sequencing or microsatellite analysis had been performed. In four unrelated families, we identified two distinct NF1 mutations within the same family. This fortuitous association points out the need to perform an exhaustive NF1 screening in the case of molecular discordant-related patients. A genotype-phenotype study was performed in patients harboring a truncating ( N = 368), in-frame splicing ( N = 36), or missense ( N = 35) mutation. The association analysis of these mutation types with 12 common NF1 clinical features confirmed a weak contribution of the allelic heterogeneity of the NF1 mutation to the NF1 variable expressivity. [ABSTRACT FROM AUTHOR]

Summary: HCV infection is a global health problem that affects 170 million people worldwide. The severity of the disease varies from asymptomatic chronic infection to cirrhosis and hepatocellular carcinoma (HCC). Recently, the standard of care for genotype 1 patients has greatly improved with the addition of protease inhibitors (telaprevir or boceprevir) to pegylated interferon (PegIFN) and ribavirin (RBV). The prediction of fibrosis progression and the response to antiviral treatment are two major issues in the management of patients with chronic hepatitis C. Differential expression of mRNAs was first analyzed for both progression of fibrosis and treatment response. Specific polymorphisms, associated with either fibrosis or viral response, were identified thanks to major improvements in genome scanning technologies. Since 2009, several independent genome wide association studies (GWAS) have reported an association between genetic polymorphisms within the IL-28B promoter and both natural and treatment-induced clearance in genotype 1 infected patients. These different studies showed the strong association and the importance of IL-28B polymorphisms in the treatment response. Combining the different genetic factors could improve their predictive value and help identify patients at a high risk of progression of fibrosis as well as those with a lower chance of responding to treatment. The aim of this review was to discuss the genomic factors (mRNAs, miRNAs, and SNPs) and HCV infection with clinical implications for either progression of fibrosis or treatment response. Recent findings on the IL-28B polymorphism and its application in clinical practice will also be discussed. [ABSTRACT FROM AUTHOR]

Although neurofibromatosis 1 (NF1) is a common Mendelian disorder with autosomal-dominant inheritance, its expression is highly variable and unpredictable. Many NF1 patients have been genotyped but few allelephenotype correlations have been identified. NF1 genotype-phenotype correlations are difficult to identify because of the complexity of the NF1 phenotype, its strong age dependency, the relatedness of many clinical features and the huge heterogeneity of pathogenic NF1 mutations. Some NF1 patients with a given NF1 mutation may develop very severe disease while others with the same mutation have only mild symptoms. This phenotypic variability may be due to both modifier genes and environmental factors. Recent targeted strategies have identified several interesting candidate modifier genes. [ABSTRACT FROM AUTHOR]

The wide clinical spectrum of the ABCB4 gene (ATP-binding cassette subfamily B member 4) deficiency syndromes in humans includes low phospholipid-associated cholelithiasis (LPAC), intrahepatic cholestasis of pregnancy (ICP), oral contraceptives-induced cholestasis (CIC), and progressive familial intrahepatic cholestasis type 3 (PFIC3). No ABCB4 mutations are found in a significant proportion of patients with these syndromes. In the present study, 102 unrelated adult patients with LPAC (43 patients) or CIC/ICP (59 patients) were screened for ABCB4 mutations using DNA sequencing. Heterozygous ABCB4 point or short insertion/deletion mutations were found in 37% (16/43) of the LPAC patients and in 27% (16/59) of the ICP/CIC patients. High-resolution gene dosage methodologies were used in the 70 negative patients. Here, we describe for the first time ABCB4 partial or complete heterozygous deletions in 7% (3/43) of the LPAC patients, and in 2% (1/59) of the ICP/CIC patients. Our observations urge to systematically test patients with LPAC, ICP/CIC, and also children with PFIC3 for the presence of ABCB4 deletions using molecular tools allowing detection of gross rearrangements. In clinical practice, a comprehensive ABCB4 alteration-screening algorithm will permit the use of ABCB4 genotyping to confirm the diagnosis of LPAC or ICP/CIC, and allow familial testing. An early diagnosis of these biliary diseases may be beneficial because of the preventive effect of ursodeoxycholic acid on biliary complications. Further comparative studies of patients with well-characterized genotypes (including deletions) and phenotypes will help determine whether ABCB4 mutation types influence clinical outcomes. [ABSTRACT FROM AUTHOR]

Background Neurofibromatosis type 1 (NF1) is a tumor predisposition syndrome with a worldwide birth incidence of one in 2500. Genetic factors unrelated to the NF1 locus are thought to influence the number of plexiform neurofibromas (PNFs) in patients with NF1, but no factors have been identified to date. Methods We used high-resolution array comparative genomic hybridization of tissue from 22 PNFs obtained from 18 NF1 patients to identify modifier genes involved in PNF development. We used a family-based association test for five previously identified cancer-susceptibility tag single-nucleotide polymorphisms (rs1063192, rs2151280, rs2218220, rs10757257, and rs7023329) located in chromosomal region 9p21.3 in 1105 subjects (740 NF1 patients and 365 non-affected relatives) from 306 families. To confirm the functional role of rs2151280, we used real-time quantitative reverse transcription–polymerase chain reaction to analyze the expression of cyclin-dependent kinase inhibitor 2A (CDKN2A), CDKN2B, alternate reading frame (ARF), and antisense noncoding RNA in the INK4 locus (ANRIL) in the peripheral blood of 124 NF1 patients. Relationships between CDKN2A, CDKN2B, ARF, and ANRIL expression and the rs2151280 genotype were tested by the Kruskal–Wallis test. All statistical tests were two-sided. Results In NF1-associated PNFs, 9p21.3 deletions (including the CDKN2A/B-ANRIL locus) were found as the only recurrent somatic alterations. Single-nucleotide polymorphism rs2151280 (located in ANRIL) was statistically significantly associated with the number of PNFs (P < .001) in NF1 patients. In addition, allele T of rs2151280 was statistically significantly associated with reduced ANRIL transcript levels (P < .001), suggesting that modulation of ANRIL expression mediates PNF susceptibility. Conclusion Identification of ANRIL as a modifier gene in NF1 may offer clues to the molecular pathogenesis of PNFs, particularly neurofibroma formation, and emphasizes the unanticipated role of large noncoding RNA in activation of critical regulators of tumor development. [ABSTRACT FROM PUBLISHER]

A large noncoding RNA called ANRIL (for antisense noncoding RNA in the INK4 locus) has been identified within the p15/CDKN2B-p16/CDKN2Ap14/ ARF gene cluster. While the exact role of ANRIL awaited further elucidation, common disease genomewide association studies (GWAS) have surprisingly identified the ANRIL gene as a genetic susceptibility locus shared associated by coronary disease, intracranial aneurysm and also type 2 diabetes. Expression studies have confirmed the coregulation of p15/CDKN2B, p16/ CDKN2A, p14/ARF, and ANRIL. Among the cluster, ANRIL expression showed the strongest association with the multiple phenotypes linked to the 9p21.3 region. More recent GWAS also identified ANRIL as a risk locus for gliomas and basal cell carcinomas in accordance with the princeps observation. Moreover, a mouse model has confirmed the pivotal role of ANRIL in regulation of CDKN2A/B expression through a cisacting mechanism and its implication in proliferation and senescence. The implication of ANRIL in cellular aging has provided an attractive unifying hypothesis to explain its association with various susceptibility risk factors. ANRIL identification emphasizes the underestimated role of long noncoding RNAs. Many GWAS have identified trait-associated SNPs that felt in noncoding genomic regions. It is conceivable to anticipate that long, noncoding RNAs will map to many of these "gene deserts." [ABSTRACT FROM AUTHOR]

Treatment for chronic hepatitis C virus (HCV) infection has evolved considerably in the last years. The standard of care (SOC) for HCV infection consists in the combination of pegylated interferon (PEG-IFN) plus ribavirin. However, it only induces a sustained virological response (SVR) in half of genotype 1-infected patients. Several viral and host factors have been associated with non-response: steatosis, obesity, insulin resistance, age, male sex, ethnicity and genotypes. Many studies have demonstrated that in non-responders, some interferon-stimulated genes were upregulated before treatment. Those findings associated to clinical, biochemical and histological data may help detect responders before starting any treatment. This is a very important issue because the standard treatment is physically and economically demanding. The future of HCV treatment would probably consist in the addition of specifically targeted antiviral therapy for HCV such as protease and/or polymerase inhibitors to the SOC. In genotype 1 patients, very promising results have been reported when the protease inhibitor telaprevir or boceprevir is added to the SOC. It increases the SVR rates from approximately 50% (PEG-IFN plus ribavirin) to 70% (for patients treated with a combination of PEG-IFN plus ribavirin plus telaprevir). Different elements are associated with non-response: (i) viral factors, (ii) host factors and (iii) molecular mechanisms induced by HCV proteins to inhibit the IFN signalling pathway. The goal of this review is to present the mechanisms of non-response, to overcome it and to identify factors that can help to predict the response to anti-HCV therapy. [ABSTRACT FROM AUTHOR]

In hepatocytes, the accumulation of unfolded proteins in the endoplasmic reticulum (ER) causes ER stress and the unfolded protein response (UPR), mediated by the ER-resident stress sensors ATF-6, IRE1, and PERK. UPR-responsive genes are involved in the fate of ER-stressed cells. Cells carrying hepatitis C virus (HCV) subgenomic replicons exhibit in vitro ER stress and suggest that HCV inhibits the UPR. Since in vivo ER homeostasis is unknown in livers with chronic HCV infection, we investigated ER stress and the UPR in liver samples from untreated patients with chronic hepatitis C (CHC), in comparison with normal livers. Electron microscopy, western blotting, and real-time RT-PCR were used in liver biopsy specimens. Electron microscopy identified features showing ER stress in hepatocyte samples from patients with CHC; however, 'ER-stressed' hepatocytes were found in clusters (3-5 cells) that were scattered in the liver parenchyma. Western blot analysis confirmed the existence of hepatic ER stress by showing activation of the three ER stress sensors ATF-6, IRE1, and PERK in CHC. Real-time RT-PCR showed no significant induction of UPR-responsive genes in CHC. In contrast, genes involved in the control of diffuse processes such as liver proliferation, inflammation, and apoptosis were significantly induced in CHC. In conclusion, livers from patients with untreated CHC exhibit in vivo hepatocyte ER stress and activation of the three UPR sensors without apparent induction of UPR-responsive genes. This lack of gene induction may be explained by the inhibiting action of HCV per se (as suggested by in vitro studies) and/or by our finding of the localized nature of hepatocyte ER stress. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

INTRODUCTION: The preoperative diagnosis of intraductal papillary mucinous neoplasms (IPMN) of the pancreas must be as reliable as possible because large or even total pancreatectomy may be necessary. Early diagnosis of malignant forms is important to improve prognosis. The diagnostic accuracy of fluid analysis using endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) has been confirmed in cystic lesions of the pancreas. It is not known if these results can be applied to IPMN. AIMS: To determine the levels of biochemical and tumor markers in fluid from EUS-FNA in patients with IPMN and to assess the impact on the diagnosis of IPMN. PATIENTS AND METHODS: In total, 41 patients (14 men, median age 64 yr) underwent EUS-FNA before surgical resection of IPMN in our center. Levels of amylase, lipase, carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 19.9, and CA 72.4 were measured in the cyst fluid. The performance of the markers was retrospectively evaluated for: (a) a positive diagnosis of IPMN, using cutoffs validated in the literature for mucinous pancreatic lesions and (b) an assessment of malignancy ( i.e., high-grade dysplasia or invasive carcinoma) compared with the final pathological examination of the surgical specimen. RESULTS: EUS-FNA was performed in dilated branch ducts (BD) in 39 cases and in the main pancreatic duct in 2 cases. No serious complications occurred. The median fluid levels of amylase, lipase, CEA, CA 19.9, and CA 72.4 were 20,155 U/mL, 59,500 U/mL, 173 ng/mL, 6,400 U/mL, and 11.5 U/mL, respectively. A CEA level >200 ng/mL and a CA 72.4 >40 U/mL had a 44% and a 39% sensitivity, respectively, for the diagnosis of IPMN. The levels of CEA, CA 19.9, and CA 72.4 were significantly different between benign and malignant IPMN. The sensitivity, specificity, and positive (PPV) and negative predictive values (NPV) of a CEA level >200 ng/mL for the diagnosis of malignant IPMN were 90%, 71%, 50%, and 96%, respectively. The sensitivity, specificity, PPV, and NPV of a CA 72.4 level >40 U/mL for this purpose were 87.5%, 73%, 47%, and 96%, respectively. CONCLUSION: CEA and CA 72.4 in pancreatic cyst fluid have excellent NPVs in the preoperative differential diagnosis of benign versus malignant IPMN, and might reinforce the decision of not to operate on patients with BD-type without predictive factors of malignancy. [ABSTRACT FROM AUTHOR]

Background & Aims: Our study was designed to test the association between insulin resistance (IR) and hepatitis C virus (HCV) genotypes, serum HCV RNA level and liver fibrosis stage in a large prospective cohort of chronic hepatitis C (CHC) patients. Methods: Six hundred consecutive patients (CHC, n = 500; chronic hepatitis B (CHB), n = 100) were evaluated on the day of liver biopsy. IR (Homeostasis Model for Assessment of Insulin Resistance) and all components of the metabolic syndrome were assessed. By logistic regression, independent factors associated with IR and those associated with significant fibrosis were assessed in nondiabetic and noncirrhotic CHC, respectively. Parameters of IR were compared between hepatitis B and 240 CHC matched by epidemiologic, metabolic, and histologic features. Results: IR was present in 32.4% of the 462 nondiabetic CHC and associated with the metabolic syndrome, genotypes 1 and 4, significant fibrosis, and severe steatosis. IR was diagnosed in 15% of 145 CHC without metabolic syndrome or significant fibrosis, and associated with genotypes 1 and 4, high serum HCV RNA level, and moderate-severe necroinflammation. Significant fibrosis was present in 51.1% of the 454 noncirrhotic CHC patients and associated with male sex, age >40 years, IR, moderate-severe necroinflammation, and severe steatosis. IR was less frequent in CHB than in matched CHC (5% vs 35%, respectively, P < .001). Conclusions: IR is a specific feature of CHC, associated with genotypes 1 and 4 and high serum HCV RNA level. Significant fibrosis is associated with IR independent from steatosis. [Copyright &y& Elsevier]

This article discusses findings of a study, which assessed the expression profile of selected genes involved in inflammatory vascular damage in patients with hepatitis C virus-associated mixed cryoglobulinemia vasculitis (HCV-MC), patients with polyarteritis nodosa (PAN), and patients with non-inflammatory idiopathic neuropathy. Medium-sized blood vessels are affected by MC, which is a systemic vasculitis.

Background & Aims: The molecular mechanisms of hepatocellular carcinoma have been studied, but little is known of the changes in liver gene expression during the different stages of chronic hepatitis C virus (HCV) infection, in particular the transition from mild to moderate fibrosis. Methods: We used real-time quantitative RT PCR to study the messenger RNA expression of 240 selected genes in 2 pools of liver specimens according to the stages of fibrosis (Metavir score; mild fibrosis = F1 and septal fibrosis = F2). Genes whose expression differed between pools (F2 vs F1) by at least 2-fold were selected. In addition, the expression level of these selected genes then was assessed in each of the 62 individual samples (F4, n = 6; F3, n = 17; F2, n = 21; vs F1, n = 18). Results: The 22 genes that were up-regulated in the 21 F2 samples relative to the 18 F1 samples mainly encoded genes involved in cytoskeleton (KRT 19 and SCG 10), growth factors/cytokines (CXCL6, interleukin 8 [IL8], IL1A, IL2, and CXCL10), or growth factor receptors (CCR2, CXCR3, and CXCR4), or were involved in extracellular matrix production (COL1A1, CHI3L, and SPP1), in extracellular matrix remodeling (TIMP1, MMP7, and MMP9), and in cell junction (ITGA2 and CLDN 4). When hierarchically clustering the F2 and F1 samples according to the expression of the 11 most discriminatory genes (KRT 19, COL1A1, STMN2, CXCL6, CCR2, TIMP1, IL8, IL1A, ITGA2, CLDN 4, and IL2), the patient population was categorized into 2 subgroups: F1 and F2. Specifically, 15 of 18 F1 (83%) and 19 of 21 F2 (90%) were classified correctly (P < 10−5). We also studied the messenger RNA expression of these 240 selected genes in normal liver in comparison with F1. Genes dysregulated in the transition from normal liver to F1 mainly were interferon-inducible genes, and therefore were very different from those dysregulated in the transition from F1 to F2. Conclusions: Genes involved in extracellular matrix turnover and immune response are implicated in the transition from mild to moderate fibrosis. Eleven of the genes could form the basis for the gene expression signature of mild versus moderate fibrosis in patients with chronic hepatitis C. [Copyright &y& Elsevier]

Noonan syndrome was recently reported to be caused by mutations in the PTPN11 gene in 40% of the cases. This gene encodes the nonreceptor-type protein tyrosine phosphatase SHP-2 and has been shown to be self down-regulated with the concurrency of two SH2 domains. Insertion of a specific loop (D′EF) from N-terminal SH2 domain into the SHP-2 active-site is responsible for the reversible inhibition of the phosphatase activity. Here we report the first in frame trinucleotide deletion resulting in the removal of Aspartate 61 (D61del), a key residue of the N-terminal SH2 D′EF loop. Energetic-based structural analysis and electrostatic calculations carried out on the wild-type and mutant proteins predict lower stability of the D′EF loop for the D61del variant as compared to the wild type indicating better access to the active site and most likely an enzyme activated for longer extent. Similar computations were performed on the previously functionally characterized gain-of-function D61Y mutant and similar behaviors were observed. The simulation data for the D61del and D61Y mutants suggest that both variants could yield more catalytic cycles than the wild-type molecule in the same timespan because of the opening of the active site. It also supports the notion that D61 plays a major role for proper down-regulation of the protein tyrosine phosphatase activity of SHP-2. Proteins 2005. © 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Background: Human chorionic gonadotrophin beta (hCGbeta) is expressed in several non-trophoblastic tumours, and this is usually associated with aggressive behaviour. Little is known about hCGbeta expression in Barrett's adenocarcinoma.Materials and Methods: We determined the hCGbeta profile in a large series of surgically resected Barrett's adenocarcinoma (a) at mRNA level using real-time quantitative reverse-transcription polymerase chain reaction analysis and (b) at protein level using immunohistochemistry with a polyclonal antibody and with a monoclonal antibody specific for free hCGbeta. We then sought links between the hCGbeta protein expression pattern and clinical and pathological parameters, including patient outcome as well as vascular endothelial growth factor (VEGF) expression.Results: hCGbeta protein expression was observed in 43 of 76 (57%) Barrett's adenocarcinomas. We showed a strong correlation between hCGbeta protein abundance and CGB mRNA level. We observed a statistical link between hCGbeta protein expression and infiltrative tumour type ( P=0.023), perineural neoplastic invasion ( P=0.007) and VEGF protein expression ( P=0.016). hCGbeta expression tended to be associated with a poor outcome (16% versus 36% survival 8 years after resection).Conclusion: Expression of hCGbeta correlates with specific infiltrative characteristics and is associated with higher VEGF expression. Both molecules may play a co-ordinated role in the development of Barrett's adenocarcinomas. [ABSTRACT FROM AUTHOR]

The aim of this study was to define the use of a new cardiac troponin I (cTnI) assay for emergency patients with chest pain and no specific electrocardiographic changes consistent with the presence of ischemia. Patients (n=106) admitted in Emergency/Cardiology Departments for chest pain and suspicion of acute coronary syndrome (ACS) were randomized into two diagnosis groups (ACS or non-ACS) by two independent cardiologists. cTnI measurements were performed at admission, and 6 hours and 12 hours later with a new generation assay (Access AccuTnI, Beckman Coulter). Using an upper reference limit of 0.04 μg/l, 27 patients had a cTnI elevation not related to the final diagnosis of ischemia; the positive predictive value (PPV) was 67% with specificity 48%. The decisional value was re-defined and set at 0.16 μg/l, a concentration corresponding to the 99th percentile of the non-ACS patient group. Precision (coefficient of variation) was 8% at this level, PPV 97% and specificity 98%. This new decisional value is now used in our institution and could be included in standard care guidelines to improve the management of patients presenting chest pain in emergency departments. [ABSTRACT FROM AUTHOR]

Background: Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder with a complex range of clinical symptoms. The hallmark of NF1 is the onset of heterogeneous (dermal or plexiform) benign neurofibromas. Plexiform neurofibromas can give rise to malignant peripheral nerve sheath tumors (MPNSTs), and the underlying molecular mechanisms are largely unknown. Results: To obtain further insight into the molecular pathogenesis of MPNSTs, we used real-time quantitative RT-PCR to quantify the mRNA expression of 489 selected genes in MPNSTs, in comparison with plexiform neurofibromas. The expression of 28 (5.7%) of the 489 genes was significantly different between MPNSTs and plexiform neurofibromas; 16 genes were upregulated and 12 were downregulated in MPNSTs. The altered genes were mainly involved in cell proliferation (MKI67, TOP2A, CCNE2), senescence (TERT, TERC), apoptosis (BIRC5/Survivin, TP73) and extracellular matrix remodeling (MMP13, MMP9, TIMP4, ITGB4). More interestingly, other genes were involved in the Ras signaling pathway (RASSF2, HMMR/RHAMM) and the Hedgehog-Gli signaling pathway (DHH, PTCH2). Several of the down-regulated genes were Schwann cell-specific (L1CAM, MPZ, S100B, SOX10, ERBB3) or mast cell-specific (CMA1, TPSB), pointing to a depletion and/or dedifferentiation of Schwann cells and mast cells during malignant transformation of plexiform neurofibromas. Conclusion: These data suggest that a limited number of signaling pathways, and particularly the Hedgehog-Gli signaling pathway, may be involved in malignant transformation of plexiform neurofibromas. Some of the relevant genes or their products warrant further investigation as potential therapeutic targets in NF1. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess the usefulness of real-time PCR as a quantitative, highly reproducible, and sensitive method, for detecting and quantifying p53 recombinant adenovirus in biological samples from cancer patients receiving injections of Ad5CMV-p53. The dynamic range of this real-time PCR-based assay was wide (at least five orders of magnitude). Our assay used an internal positive control in the same PCR tube that is capable of detecting residual PCR inhibitors. Serial spiked samples in plasma with known quantities of Ad5CMV-p53 were evaluated. The minimum detection limit was 2 pfu per PCR (∼50 pfu per ml of plasma) and the quantification values were reproducible. A total of 2069 controls tested with 1780 plasma samples from 286 patients enrolled in gene therapy trials using Ad5CMV-p53 were investigated. Using calibrators to adjust the quantitation value, the results confirmed the good performance of the assay. In conclusion, the high sensitivity, simplicity and reproducibility of the real-time Ad5CMV-p53 assay, allowing screening of large numbers of samples, combined with its wide dynamic range, make this method particularly suitable for monitoring gene therapy trials. [Copyright &y& Elsevier]

We recently demonstrated that the product of the HERV-W env gene, a retroviral envelope protein also dubbed syncytin, is a highly fusogenic membrane glycoprotein inducing the formation of syncytia on interaction with the type D mammalian retrovirus receptor. In addition, the detection of HERV-W Env protein (Env-W) expression in placental tissue sections led us to propose a role for this fusogenic glycoprotein in placenta formation. To evaluate this hypothesis, we analyzed the involvement of Env-W in the differentiation of primary cultures of human villous cytotrophoblasts that spontaneously differentiate by cell fusion into syncytiotrophoblasts in vitro. First, we observed that HERV-W env mRNA and glycoprotein expression are colinear with primary cytotrophoblast differentiation and with expression of human chorionic gonadotropin (hCG), a marker of syncytiotrophoblast formation. Second, we observed that in vitro stimulation of trophoblast cell fusion and differentiation by cyclic AMP is also associated with a concomitant increase in HERV-W env and hCG mRNA and protein expression. Finally, by using specific antisense oligonucleotides, we demonstrated that inhibition of Env-W protein expression leads to a decrease of trophoblast fusion and differentiation, with the secretion of hCG in culture medium of antisense oligonucleotide-treated cells being decreased by fivefold. Taken together, these results strongly support a direct role for Env-W in human trophoblast cell fusion and differentiation. [ABSTRACT FROM AUTHOR]

Systemic mastocytosis (SM) is a rare disease caused by an abnormal mast cell accumulation in various tissues. Two classes of constitutive activating c-kit mutations are found in SM. The most frequent class occurs in the catalytic pocket coding region with substitutions at codon 816 and the other in the intracellular juxtamembrane coding region. Therefore, kinase inhibitors that block mutated c-kit activity might be used as therapeutic agents in SM. Here, we show that STI571 inhibits both wild-type and juxtamembrane mutant c-kit kinase activity, but has no effect on the activity of the D816 V mutant. Accordingly, STI571 selectively decreases the survival of normal mast cell and of mast cell lines either with juxtamembrane c-kit mutations, but not that of tumoral mast cell from patient with SM or of mast cell lines with the D816 V mutation. Therefore, STI571 is not a good candidate to treat SM and specific kinase inhibitors should be designed to inhibit constitutive activating mutations at codon 816.Oncogene (2003) 22, 660–664. doi:10.1038/sj.onc.1206120 [ABSTRACT FROM AUTHOR]

Examines the biological characteristics of the tumor of inflammatory breast cancer (IBC) by comparing the overexpression of oncogenes ERBB2, MYC, CCND1 and RHOC and TP53 gene mutation rates in IBC. Analysis of the TP53 gene status in IBC and locally advanced breast cancer; Factor attributed to the clinical aggresiveness of the TP53 mutation and ERBB2 overexpression in IBC; Effect of the absence of TP53 function on genome instability.

The recent cloning of a second estrogen receptor (ER), designated ERβ, has prompted a reevaluation of the role of ERs in breast cancer. We have developed and validated a real-time RT–PCR assay to quantify ERα and ERβ gene expression at the mRNA level in a series of 131 patients with unilateral invasive primary breast cancer. Although ERβ expression showed wide variations in tumor tissues, its range (nearly three orders of magnitude) was smaller than that of ERα (nearly four orders of magnitude), suggesting that ERβ is more tightly controlled than ERα. We observed a negative correlation between ERα and ERβ expression. ‘ERα-negative’ tumors (containing very low ERα mRNA levels) were associated with SBR histopathological grade III, RB1 underexpression and ERBB2 overexpression, confirming that ERα negativity delineates poorly differentiated tumors. The amount of ERα mRNA (but not that of ERβ mRNA) increased with age and was consequently higher in postmenopausal patients' tumors. Expression of ERα (but not that of ERβ) also correlated strongly with progesterone receptor (PR) and PS2 expression, suggesting that ERα has stronger transcriptional activity than ERβ towards genes containing an ERE (estrogen response element) in their promoters. Interestingly, we found a negative correlation between the expression of ERβ (but not ERα) and CCND1, which contains an AP1 element but not an ERE in its promoter. Taken together, these data confirm that ERα and ERβ play different roles in breast cancer, partly by mediating the transcription of various genes via different types of DNA enhancer. PR and PS2 seem to be mainly ERα-responsive genes, whereas CCND1 may be mainly ERβ-responsive. Our findings also underline the need for a reliable method, providing full range of quantitative values, to determine ERα and ERβ status in the... [ABSTRACT FROM AUTHOR]

We recently identified CGA (coding for the alpha subunit of glycoprotein hormones) as a new estrogen receptor alpha (ERα)-responsive gene in human breast tumors. Here, we assessed the relationship between CGA status (as determined by real-time quantitative RT–PCR) and the response to tamoxifen therapy in a well-defined cohort of 125 ERα-positive postmenopausal breast cancer patients treated with primary surgery followed by adjuvant tamoxifen alone. CGA overexpression, observed in 37.6% of patients, was associated with good relapse-free survival (P=0.037; univariate analysis). CGA status, combined with ERBB2 status (a marker of poor outcome), was an independent predictor of the response to tamoxifen (P=0.020; multivariate analysis). CGA status, especially when combined with ERBB2 status, may thus provide useful predictive information on tamoxifen responsiveness in breast cancer. Oncogene (2001) 20, 6955–6959. [ABSTRACT FROM AUTHOR]

Little is known of the function and clinical significance of the androgen receptor (AR) in human breast cancer. Paradoxically, synthetic progestins, such as medroxyprogesterone acetate, are used for second line hormone therapy of breast cancer following tamoxifen failure. A sensitive and accurate assay for AR expression in breast tumors is thus required. Here we have developed and validated a real-time RT–PCR assay to quantify AR gene expression at the mRNA level in a series of 131 patients with unilateral invasive primary breast tumors. AR expression varied widely in tumor tissues (by at least 3 orders of magnitude), being underexpressed in 24/131 (18.3%) and overexpressed in 45/131 (34.4%) relative to normal breast tissues. We observed links (or trends) between AR status and age, menopausal status, Scarff–Bloom–Richardson histopathological grade, lymph node status and estrogen receptor α and progesterone receptor status. High AR mRNA levels were negatively linked to MYC gene overexpression (P = 8×10–6), confirming previous in vitro studies. Our results also suggest a role of the ARA70 gene (which encodes a major AR co-activator) in the AR pathway dysregulation observed in breast cancer. This simple, rapid and semi-automated method will be useful for screening cancer patients for altered AR expression and for predicting the response to androgen therapy in AR-related cancer patients. [ABSTRACT FROM PUBLISHER]