Chemotherapy of advanced small-bowel adenocarcinoma: a multicenter AGEO study

Les adénocarcinomes de l’intestin grêle (AIG) sont des tumeurs rares et de mauvais pronostic à un stade avancé. Les données publiées concernant l’efficacité de la chimiothérapie palliative sont peu nombreuses. Le but de notre étude était d’évaluer l’efficacité et la tolérance de différents protocoles « modernes » de chimiothérapie et de comparer l’efficacité des chimiothérapies à base de sels de platine dans le traitement de première ligne des AIG avancés. Cette étude rétrospective multicentrique a inclus 93 patients (sexe masculin : 53 % ; âge médian : 56 ans ; site primitif duodénal : 53 %) avec un AIG avancé (métastatique : 86 %) traités par LV5FU2 (n = 10), FOLFOX (n = 48), FOLFIRI (n = 19) ou LV5FU2- cisplatine (n = 16). Le taux de toxicité grade 3-4 était significativement plus fréquent dans le groupe de patients traités par LV5FU2-cisplatine (75 %) comparativement aux autres groupes de patients (p = 0,001). Les médianes de survie sans progression (SSP) étaient de 7,7 ; 6,9 ; 6,0 et 4,8 mois (p = 0,16) et les médianes de survie globale (SG) étaient de 13,5 ; 17,8 ; 10,6 et 9,3 mois (p = 0,25) pour les quatre groupes de patients traités par LV5FU2, FOLFOX, FOLFIRI et LV5FU2-cisplatine, respectivement. En analyse multivariée, l’indice de performance OMS à 2 (p < 0,0001) ainsi que des taux élevés d’ACE (p = 0,02) et de CA 19-9 (p = 0,03) avant traitement étaient les seuls facteurs indépendants significativement associés à un mauvais pronostic. Dans le sous-groupe de patients traités par sels de platine, ceux qui ont reçu une chimiothérapie par FOLFOX avaient de meilleures SSP et SG que les patients traités par LV5FU2-cisplatine. En analyse multivariée, le traitement par FOLFOX était un facteur significatif et indépendant de survie prolongée en termes de SSP (p < 0,0001) et SG (p = 0,02). Ainsi, cette étude, la plus grande rapportée à ce jour, suggère d’une part que l’indice de performance OMS et les taux d’ACE et CA 19-9 avant traitement sont des facteurs pronostiques indépendants de survie et, d’autre part que la chimiothérapie par FOLFOX est le traitement de choix en première ligne des AIG avancés

Upstream ORF affects MYCN translation depending on exon 1b alternative splicing

<p>Abstract</p> <p>Background</p> <p>The <it>MYCN </it>gene is transcribed into two major mRNAs: one full-length (<it>MYCN) </it>and one exon 1b-spliced (<it>MYCN</it>^{Δ1<it>b</it>}) mRNA. But nothing is known about their respective ability to translate the MYCN protein.</p> <p>Methods</p> <p>Plasmids were prepared to enable translation from the upstream (uORF) and major ORF of the two <it>MYCN </it>transcripts. Translation was studied after transfection in neuroblastoma SH-EP cell line. Impact of the upstream AUG on translation was evaluated after directed mutagenesis. Functional study with the two <it>MYCN </it>mRNAs was conducted by a cell viability assay. Existence of a new protein encoded by the <it>MYCN</it>^{Δ1<it>b </it>}uORF was explored by designing a rabbit polyclonal antibody against a specific epitope of this protein.</p> <p>Results</p> <p>Both are translated, but higher levels of protein were seen with <it>MYCN</it>^{Δ1<it>b </it>}mRNA. An upstream ORF was shown to have positive cis-regulatory activity on translation from <it>MYCN </it>but not from <it>MYCN</it>^{Δ1<it>b </it>}mRNA. In transfected SH-EP neuroblastoma cells, high MYCN dosage obtained with <it>MYCN</it>^{Δ1<it>b </it>}mRNA translation induces an antiapoptotic effect after serum deprivation that was not observed with low MYCN expression obtained with <it>MYCN </it>mRNA. Here, we showed that MYCNOT: <it>MYCN </it>Overlap Transcript, a new protein of unknown function is translated from the upstream AUG of <it>MYCN</it>^{Δ1<it>b </it>}mRNA.</p> <p>Conclusions</p> <p>Existence of upstream ORF in <it>MYCN </it>transcripts leads to a new level of MYCN regulation. The resulting MYCN dosage has a weak but significant anti-apoptotic activity after intrinsic apoptosis induction.</p

Heterologous Protein Expression Is Enhanced by Harmonizing the Codon Usage Frequencies of the Target Gene with those of the Expression Host

Synonymous codon replacement can change protein structure and function, indicating that protein structure depends on DNA sequence. During heterologous protein expression, low expression or formation of insoluble aggregates may be attributable to differences in synonymous codon usage between expression and natural hosts. This discordance may be particularly important during translation of the domain boundaries (link/end segments) that separate elements of higher ordered structure. Within such regions, ribosomal progression slows as the ribosome encounters clusters of infrequently used codons that preferentially encode a subset of amino acids. To replicate the modulation of such localized translation rates during heterologous expression, we used known relationships between codon usage frequencies and secondary protein structure to develop an algorithm (“codon harmonization”) for identifying regions of slowly translated mRNA that are putatively associated with link/end segments. It then recommends synonymous replacement codons having usage frequencies in the heterologous expression host that are less than or equal to the usage frequencies of native codons in the native expression host. For protein regions other than these putative link/end segments, it recommends synonymous substitutions with codons having usage frequencies matched as nearly as possible to the native expression system. Previous application of this algorithm facilitated E. coli expression, manufacture and testing of two Plasmodium falciparum vaccine candidates. Here we describe the algorithm in detail and apply it to E. coli expression of three additional P. falciparum proteins. Expression of the “recoded” genes exceeded that of the native genes by 4- to 1,000-fold, representing levels suitable for vaccine manufacture. The proteins were soluble and reacted with a variety of functional conformation-specific mAbs suggesting that they were folded properly and had assumed native conformation. Codon harmonization may further provide a general strategy for improving the expression of soluble functional proteins during heterologous expression in hosts other than E. coli

Prediction of survival with second-line therapy in biliary tract cancer: Actualisation of the AGEO CT2BIL cohort and European multicentre validations

BACKGROUND: The benefit of second-line chemotherapy (L2) over standard first-line (L1) gemcitabine plus cisplatin (GEMCIS) or oxaliplatin (GEMOX) chemotherapy in advanced biliary tract cancer (aBTC) is unclear. Our aim was to identify and validate prognostic factors for overall survival (OS) with L2 in aBTC to guide clinical decisions in this setting. METHODS: We performed a retrospective analysis of four prospective patient cohorts: a development cohort (28 French centres) and three validation cohorts from Italy, UK and France. All consecutive patients with aBTC receiving L2 after GEMCIS/GEMOX L1 between 2003 and 2016 were included. The association of clinicobiological data with OS was investigated in univariate and multivariate Cox analyses. A simple score was derived from the multivariate model. RESULTS: The development cohort included 405 patients treated with L1 GEMOX (91%) or GEMCIS. Of them, 55.3% were men, and median age was 64.8 years. Prior surgical resection was observed in 26.7%, and 94.8% had metastatic disease. Performance status (PS) was 0, 1 and 2 in 17.8%, 52.4% and 29.7%, respectively. Among 22 clinical parameters, eight were associated with OS in univariate analysis. In multivariate analysis, four were independent prognostic factors (p &lt; 0.05): PS, reason for L1 discontinuation, prior resection of primary tumour and peritoneal carcinomatosis. The model had the Harrell's concordance index of 0.655, a good calibration and was validated in the three external cohorts (N = 392). CONCLUSION: We validated previously reported predictive factors of OS with L2 and identified peritoneal carcinomatosis as a new pejorative factor in nearly 800 patients. Our model and score may be useful in daily practice and for future clinical trial design

Novel Roles of cAMP Receptor Protein (CRP) in Regulation of Transport and Metabolism of Carbon Sources

CRP (cAMP receptor protein), the global regulator of genes for carbon source utilization in the absence of glucose, is the best-studied prokaryotic transcription factor. A total of 195 target promoters on the Escherichia coli genome have been proposed to be under the control of cAMP-bound CRP. Using the newly developed Genomic SELEX screening system of transcription factor-binding sequences, however, we have identified a total of at least 254 CRP-binding sites. Based on their location on the E. coli genome, we predict a total of at least 183 novel regulation target operons, altogether with the 195 hitherto known targets, reaching to the minimum of 378 promoters as the regulation targets of cAMP-CRP. All the promoters selected from the newly identified targets and examined by using the lacZ reporter assay were found to be under the control of CRP, indicating that the Genomic SELEX screening allowed to identify the CRP targets with high accuracy. Based on the functions of novel target genes, we conclude that CRP plays a key regulatory role in the whole processes from the selective transport of carbon sources, the glycolysis-gluconeogenesis switching to the metabolisms downstream of glycolysis, including tricarboxylic acid (TCA) cycle, pyruvate dehydrogenase (PDH) pathway and aerobic respiration. One unique regulation mode is that a single and the same CRP molecule bound within intergenic regions often regulates both of divergently transcribed operons

ESTIMATION DES COUTS DE TRAITEMENT EN PREMIERE LIGNE METASTATIQUE DU CANCER COLO-RECTAL (DES HEPATOGASTROENTEROLOGIE)

PARIS12-CRETEIL BU Médecine (940282101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Prospective study of Hepatitis E Virus infection among pregnant women in France.

International audienceBACKGROUND: Hepatitis E Virus (HEV) infection has a poor prognosis among pregnant women from high endemic countries. HEV-prevalence and incidence among pregnant women is unknown in high-income countries such as France. This prospective study was conducted to assess HEV infection in this setting. FINDINGS: An overall HEV prevalence of 7.74% was observed among 315 pregnant women. Seroprevalence was higher in south than in north of France (29.3% vs. 3.6%, p < 0.0001), and women with detectable IgG were older. No IgG seroconversion or IgM detection were observed during pregnancy. CONCLUSIONS: Data suggest that HEV infection is a rare occurrence during pregnancy even in regions of western countries with high seroprevalence rates

Strontium isotope ratios related to childhood mobility:Revisiting sampling strategies of the calcined human pars petrosa ossis temporalis

Rationale: Strontium isotope analysis can be applied to the calcined human otic capsule in the petrous part (pars petrosa ossis temporalis; PP) to gain information on childhood mobility in archaeological and forensic contexts. However, only a thin layer of the otic capsule, the inner cortex, demonstrates virtually no remodelling. This paper proposes an improved sampling method for the accurate sampling of the inner cortex of the otic capsule to ensure that 87Sr/86Sr ratios related to early childhood are obtained. Methods: Calcined rib and diaphyseal fragments and PP from ten cremation deposits are sampled for strontium isotope analysis, whereby our improved sampling strategy is applied to sample the inner cortex of the otic capsule. This allows inter- and intraskeletal 87Sr/86Sr comparison within an Iron Age collection from Oss, The Netherlands. Results: Forty percent (4/10) of the calcined PP that were evaluated for this study show marked differences in 87Sr/86Sr (0.00035–0.00065) between the inner cortex and the bone sample surrounding this layer, the external cortex that has higher remodelling rates. Differences in 87Sr/86Sr between various skeletal elements also aided in the identification of the minimum number of individuals. Conclusions: Our study demonstrates the problematic nature of the external cortex and stresses the need for a precise sampling method of the correct areas of the otic capsule. This can only be obtained by cutting the calcined PP midmodiolarly to enable adequate combustion degree assessment, and the correct identification and sampling of the inner cortex of the otic capsule