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One-anastomosis gastric bypass (OAGB) is as effective as Roux-en-Y gastric bypass (RYGB) regarding weight loss and diabetes remission. However, there are no data on gut hormone secretions after OAGB. The aim of this study was to compare fasting and postprandial secretions of gut and pancreatic hormones in OAGB versus RYGB patients.Twenty-nine patients, 16 OAGB- and 13 RYGB-operated, underwent a liquid mixed-meal tolerance test at 2 years' post-surgery. Blood was sampled before and 15, 30, 60, 90, and 120 min after meal for plasma measurement of glucose, C-peptide, insulin, glucagon, GLP-1, GIP, GLP-2, PYY, and ghrelin.Percentage of total weight loss 2 years post-surgery were -33.9 ± 1.8% for OAGB and -31.2 ± 1.6% for RYGB (p = 0.6). Four patients with persistent diabetes were excluded for further analysis. Fasting and postprandial glucose levels (peaks and area under curve values) were similar between groups. HOMA index was lower in the OAGB group (0.8 ± 0.1 vs 1.3 ± 0.2 in RYGB, p 0.05). Levels of C-peptide (or insulin) measured at 30 min were significantly lower in OAGB vs RYGB patients (6.9 ± 0.5 vs 9.7 ± 1.1 µg/l, p 0.05). No difference was observed between OAGB and RYGB groups for GLP-1, GLP-2, PYY, or ghrelin postprandial secretions, but GIP tended to be lower in OAGB vs RYGB patients (756 ± 155 vs 1100 ± 188 pg/ml for postprandial peak concentrations, p = 0.06).This is the first clinical study showing that OAGB procedure, like RYGB, results in high postprandial secretions of gut hormones, in particular GLP-1.Clinical Trials NCT03482895.

PIK3CA -related overgrowth syndrome (PROS) is a genetic disorder caused by somatic mosaic gain-of-function mutations of PIK3CA . Clinical presentation of patients is diverse and associated with endocrine disruption. Adipose tissue is frequently involved, but its role in disease development and progression has not been elucidated. Here, we created a mouse model of PIK3CA -related adipose tissue overgrowth that recapitulates patient phenotype. We demonstrate that PIK3CA mutation leads to GLUT4 membrane accumulation with a negative feedback loop on insulin secretion, a burst of liver IGFBP1 synthesis with IGF-1 sequestration, and low circulating levels. Mouse phenotype was mainly driven through AKT2. We also observed that PIK3CA mutation induces metabolic reprogramming with Warburg-like effect and protein and lipid synthesis, hallmarks of cancer cells, in vitro, in vivo, and in patients. We lastly show that alpelisib is efficient at preventing and improving PIK3CA -adipose tissue overgrowth and reversing metabolomic anomalies in both animal models and patients.

Introduction Recently, targeted therapies using BRAFV600E and MEK inhibitors (dabrafenib and trametinib, respectively) have been recommended in BRAF-mutated anaplastic thyroid carcinoma (ATC). Considering the fast development of ATC, droplet digital PCR (ddPCR) performed on fine-needle aspirate (FNA), which is a rapid, reliable, and low-cost method, appears interesting for the detection of BRAFV600E mutation in these patients and allows early initiation of targeted therapies. Results In our two patients, both presenting extensive cervical masses inaccessible to surgery, ddPCR results were available in less than 24 h. Therefore, dabrafenib and trametinib were started only a few days after first contact. Conclusions We suggest that ddPCR on FNA be used in non-resectable cervical masses for rapid BRAFV600E mutation detection in the hope that starting targeted therapies early might improve outcomes.

International audience; The identification of leptin allowed the discovery of a new endocrine system. This major adipokine controlling energy homeostasis is also involved in the regulation of neuroendocrine function and fertility. Unfortunately, leptin is not able to treat common obesity, which associates hyperleptinemia and resistance to the hormone. Conversely, treatment with recombinant leptin is effective in situations of leptin deficiency. Several pathophysiological situations associated with adipose tissue dysfunctions and abnormal regulation of leptin secretion are discussed in this review. The advantage of the potential use of the leptin assay in some pathophysiological conditions is proposed.

STUDY QUESTION How efficacious is transplantation of ovarian cortex previously exposed to chemotherapy? SUMMARY ANSWER Prior exposure to chemotherapy did not disrupt the function of cryopreserved ovarian tissue after transplantation. WHAT IS KNOWN ALREADY Ovarian tissue cryopreservation (OTC) followed by ovarian tissue transplantation (OTT) is an efficacious technique for restoration of female fertility. At least 130 children have been born following this procedure. To date, little is known about the efficacy of OTT in patients exposed to cancer chemotherapy prior to OTC. STUDY DESIGN, SIZE, DURATION This study evaluates the recovery of ovarian function and fertility in 31 consecutive patients who had received OTT, between 2005 and 2015. PARTICIPANTS/MATERIALS, SETTING, METHODS Thirty one patients, wanting children, were transplanted with autologous ovarian cortex, among which 22 patients (71%) had been exposed to chemotherapy before OTC. Recovery of ovarian function was considered total once menstruation occurred. Ovarian function recovery (OFR), ovarian graft survival, and incidence of pregnancy were related to previous chemotherapy exposure, type of chemotherapy and graft characteristics (number of grafted fragments and follicular density). MAIN RESULTS AND ROLE OF CHANCE The amount of ovarian tissue collected was the only parameter to show any significant change between patients with versus without previous chemotherapy. At 1 year after OTT, the cumulative incidence of OFR was 83% (93% in patients exposed to chemotherapy and 67% in others (P = 0.14)). A low follicular density (

Context Unlike homozygous variants, the implication of heterozygous variants on the leptin–melanocortin pathway in severe obesity has not been established. Objective To describe the frequency, the phenotype, and the genotype–phenotype relationship for heterozygous variants in LEP, LEPR, POMC, and PCSK1 in severe obesity. Methods In this retrospective study, genotyping was performed on at least 1 of the LEP, LEPR, POMC, and PCSK1 genes in 1486 probands with severe obesity (600 children, 886 adults). The phenotype was collected in 60 subjects with heterozygous variants and 16 with homozygous variants. We analyzed variant frequency, body mass index (BMI), age of obesity onset, food impulsivity, and endocrine abnormalities. Results The frequency of subjects with homozygous variants was 1.7% (n = 26), and 6.7% (n = 100) with heterozygous variants. Adults with homozygous variants had a higher BMI (66 vs 53 kg/m2, P = .015), an earlier onset of obesity (0.4 vs 5.4 years, P < .001), more often food impulsivity (83% vs 42%, P = .04), and endocrine abnormalities (75% vs 26%, P < .01). The BMI was higher for subjects with high-impact heterozygous variants (61 vs 50 kg/m², P = .045) and those with a second heterozygous variant on the pathway (65 vs 49 kg/m², P < .01). In children, no significant differences were found for the age of obesity onset and BMI. Conclusion Heterozygous variants in LEP, LEPR, POMC, and PCSK1 are frequent in severe obesity and sometimes associated with a phenotype close to that of homozygotes. These data suggest a systematic search for variants in severe early-onset obesity, to discuss therapy that targets this key pathway.

International audience; Adiponectin is a major adipokine involved in energy homeostasis that exerts insulin-sensitizing properties. The level of adiponectin is reduced in situations of insulin resistance and is negatively associated with several pathophysiological situations including abdominal obesity, metabolic syndrome, steatosis and non-alcoholic steatohepatitis, type 2 diabetes, some cancers and cognitive diseases. These aspects are discussed in this review.; L’adiponectine est une adipokine majeure de l’homéostasie énergétique qui présente des propriétés insulino-sensibilisatrices. Elle est diminuée dans les états de résistance à l’insuline et est associée négativement à plusieurs situations physiopathologiques dont l’obésité abdominale, le syndrome métabolique, la stéatose et la stéato-hépatite non alcoolique, le diabète de type 2, certains cancers et des maladies cognitives. Ces aspects sont discutés dans cette revue.

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Early specific antibody responses against SARS-CoV-2 include IgG, IgM, and IgA, but IgA may neutralize virus and control infection to a larger extent., Early action of IgA Humoral immune responses play a critical role in protecting individuals against SARS-CoV-2 infection, particularly through the activity of neutralizing antibodies. Sterlin et al. measured humoral immune responses in the serum, saliva, and bronchoalveolar lavage fluid of SARS-CoV-2–infected patients who experienced a range of COVID-19 disease severity. IgA antibodies dominated the early SARS-CoV-2–specific antibody response compared with IgG and IgM concentrations in these fluids and was associated with expansion of IgA plasmablasts with mucosal homing characteristics. IgA serum concentrations peaked 3 weeks after symptom onset but persisted for several more weeks in saliva, and serum IgA was more potent than IgG in neutralizing SARS-CoV-2. These findings highlight the potential role of IgA during early SARS-CoV-2 infection., Humoral immune responses are typically characterized by primary IgM antibody responses followed by secondary antibody responses associated with immune memory and composed of IgG, IgA, and IgE. Here, we measured acute humoral responses to SARS-CoV-2, including the frequency of antibody-secreting cells and the presence of SARS-CoV-2–specific neutralizing antibodies in the serum, saliva, and bronchoalveolar fluid of 159 patients with COVID-19. Early SARS-CoV-2–specific humoral responses were dominated by IgA antibodies. Peripheral expansion of IgA plasmablasts with mucosal homing potential was detected shortly after the onset of symptoms and peaked during the third week of the disease. The virus-specific antibody responses included IgG, IgM, and IgA, but IgA contributed to virus neutralization to a greater extent compared with IgG. Specific IgA serum concentrations decreased notably 1 month after the onset of symptoms, but neutralizing IgA remained detectable in saliva for a longer time (days 49 to 73 post-symptoms). These results represent a critical observation given the emerging information as to the types of antibodies associated with optimal protection against reinfection and whether vaccine regimens should consider targeting a potent but potentially short-lived IgA response.

BackgroundSince 1920, a decrease in serum cholesterol has been identified as a marker of severe pneumonia. We have assessed the performance of serum apolipoprotein-A1, the main transporter of HDL-cholesterol, to identify the early spread of coronavirus disease 2019 (Covid-19) in the general population and its diagnostic performance for the Covid-19.MethodsWe compared the daily mean serum apolipoprotein-A1 during the first 30 weeks of 2020 in a population that is routinely followed for a risk of liver fibrosis risk in the USA (183,112 sera) and in France (18,316 sera) in relation to a local increase in confirmed cases, and in comparison to the same period in 2019 (respectively 234,881 and 26,056 sera). We prospectively assessed the sensitivity of this marker in an observational study of 136 consecutive hospitalized cases and retrospectively evaluated its specificity in 7,481 controls representing the general population.ResultsThe mean serum apolipoprotein-A1 levels in these populations began decreasing in January 2020, compared to the same 30 weeks in 2019. This decrease was highly correlated to and in parallel with the daily increase in confirmed Covid-19 cases in the following 30 weeks, in both France and USA, including the June and mid-July recovery periods in France. Apolipoprotein-A1 at the 1.25 g/L cutoff had a sensitivity of 90.6% (95%CI84.2-95.1) and a specificity of 96.1% (95.7-96.6%) for the diagnosis of Covid-19. The area under the characteristics curve was 0.978 (0.957-0.988), and outperformed haptoglobin and liver function tests. The adjusted risk ratio for survival without transfer to intensive care unit was 5.61 (95%CI 1.02-31.0;P=0.04).ConclusionApolipoprotein-A1 could be both a sentinel of the pandemic in existing routine surveillance of the general population with no new blood sample, as well as a candidate predictor of suspected Covid-19 in multivariate analysis in cases with a negative virological test. NCT01927133, CER-2020-14.Key PointsQuestionDoes serum apolipoprotein-A1 decrease could be a very early biomarker of SARS-CoV-2 pandemic?FindingsDuring the 30 weeks of 2020 we observed in two large cohorts of patients at risk of liver fibrosis a highly significant decrease of serum apolipoprotein-A1, not observed in previous years. This decrease was highly correlated to and in parallel with the daily increase in confirmed Covid-19 cases, including the recovery period.MeaningApolipoprotein-A1 could be used as a sentinel of the pandemic in existing routine surveillance of the general population.

International audience

A major dogma in immunology has it that the IgM antibody response precedes secondary memory responses built on the production of IgG, IgA and, occasionaly, IgE. Here, we measured acute humoral responses to SARS-CoV-2, including the frequency of antibody-secreting cells and the presence of specific, neutralizing, antibodies in serum and broncho-alveolar fluid of 145 patients with COVID-19. Surprisingly, early SARS-CoV-2-specific humoral responses were found to be typically dominated by antibodies of the IgA isotype. Peripheral expansion of IgA-plasmablasts with mucosal-homing potential was detected shortly after the onset of symptoms and peaked during the third week of the disease. While the specific antibody response included IgG, IgM and IgA, the latter contributed to a much larger extent to virus neutralization, as compared to IgG. However, specific IgA serum levels notably decrease after one month of evolution. These results represent a challenging observation given the present uncertainty as to which kind of humoral response would optimally protect against re-infection, and whether vaccine regimens should consider boosting a potent, although, at least in blood, fading IgA response.One sentence SummaryWhile early specific antibody response included IgG, IgM and IgA, the latter contributed to a much larger extent to virus neutralization.

Wide-range C-reactive protein (wr-CRP) has been proposed as an economical alternative to high-sensitivity C-reactive protein (hs-CRP) for the evaluation of low-grade inflammation-associated cardiovascular risk (LGI-CVR). Concomitant values of serum hs-CRP and plasma wr-CRP ≤5 mg/L, and high-sensitivity cardiac troponin T (hs-cTnT), all assayed on Roche Diagnostics analyzers over a 1.8-year period, were extracted from a hospital laboratory database. Hs-CRP and wr-CRP values were compared (Bland-Altman method; Deming's correlation), then separately classified into low (1 mg/L), moderate (1-3 mg/L) and high (3 mg/L) LGI-CVR ranges for agreement test (κ), assessed before and after Deming's regression-based adjustment of wr-CRP (Adj-wr-CRP). Wr-CRP and hs-CRP values were strongly correlated, with linearity, whether below 5 mg/L (n = 744; τ = 0.933; p .001) or below 1 mg/L (n = 283; τ = 0.823; p .001). Overall, wr-CRP values were lower than hs-CRP (mean bias: -0.11 ± 0.17 mg/L). Agreement was good, with 8.1% of wr-CRP values misclassified compared to hs-CRP (κ: 0.874), and weakly improved after regression-based adjustment (7.7% reclassified values; κ: 0.881). Lowering the Adj-wr-CRP cutoff of the moderate LGI-CVR subrange from 1.0 to 0.9 mg/L resulted in an almost perfect agreement (3.2% reclassified data; κ: 0.950). Hs-cTnT concentration was positively associated with hs-CRP, wr-CRP, and Adj-wr-CRP (p .001). Within each LGI-CVR subrange, hs-cTnT medians were similar regardless of the hs-CRP, wr-CRP or Adj-wr-CRP used for risk classification. Based on hs-cTnT, this study supports the use of wr-CRP as a low-cost alternative to hs-CRP for cardiovascular risk evaluation.

Context The population of Guadeloupe Island exhibits a high prevalence of obesity. Objective We aimed to investigate whether rare genetic mutations in genes involved in monogenic obesity (or diabetes) might be causal in this population of Afro-Caribbean ancestry. Design and setting This was a secondary analysis of a study on obesity conducted in schoolchildren from Guadeloupe in 2013 that aimed to assess changes in children's profiles after a lifestyle intervention program. Through next-generation sequencing, we sequenced coding regions of 59 genes involved in monogenic obesity or diabetes in participants from this study. Participants and interventions A total of 25 obese schoolchildren from Guadeloupe were screened for rare mutations (nonsynonymous, splice-site, or insertion/deletion) in 59 genes. Main outcome measures Correlation between phenotypes and mutations of interest. Results We detected five rare heterozygous mutations in five different children with obesity: MC4R p.Ile301Thr and SIM1 p.Val326Thrfs*43 mutations that were pathogenic; SIM1 p.Ser343Pro and SH2B1 p.Pro90His mutations that were likely pathogenic; and NTRK2 p.Leu140Phe that was of uncertain significance. In parallel, we identified seven carriers of mutations in ABCC8 (p.Lys1521Asn and p.Ala625Val) or KCNJ11 (p.Val13Met and p.Val151Met) that were of uncertain significance. Conclusions We were able to detect pathogenic or likely pathogenic mutations linked to severe obesity in >15% of this population, which is much higher than what we observed in Europeans (∼5%).

International audience; Background: Ethnic variations have been reported in allelic frequencies of the leptin receptor gene (LEPR) with population-specific effects. We aimed to explore the association of LEPR polymorphisms with obesity, metabolic syndrome (MetS), and leptin levels in Afro-Caribbean nondiabetic subjects. Methods: Genotypic analysis of three LEPR polymorphisms (K109R, Q223R, and K656N) was performed using TaqMan allelic discrimination assays. Associations were measured with phenotypic variables, including body mass index (BMI), waist circumference (WC), and leptin levels. Linear and logistic regressions were performed to evaluate the effects of single-nucleotide polymorphisms (SNPs). Results: Mean age was 46 ± 12 years. Among the 375 participants, 29.3% were obese, 36.3% had abdominal obesity, and 18.1% had MetS. Significant association between BMI (P

Background Medial calcification in diabetes contributes to the arterial occlusive process occurring below the knee level. Adiponectin is an adipokine with atheroprotective properties and possible protective role against arterial calcification. The aim of the study was to investigate, in type 2 diabetes, the link between vascular expression and serum concentration of adiponectin and (1) peripheral arterial calcification and (2) lower limb occlusive arterial disease. Methods Scoring of peripheral vascular calcification and peripheral arterial occlusive disease, using CT-scan and color-duplex ultrasonography respectively, were conducted and explored in relation to serum adiponectin level in a cross sectional study of 197 patients with type 2 diabetes. Vascular adiponectin expression in the arterial wall of diabetic patients with and without medial calcification was evaluated by immunohistochemistry. Results Peripheral arterial calcification score was higher in patients with the highest adiponectin concentration. In a multivariate logistic regression analysis, an increase of 1 µg/mL of adiponectin was associated with a 22% increase of arterial calcification (adjusted OR = 1.22; 95% CI 1.03–1.44; p = 0.02). Arterial occlusive score was also higher in patients with adiponectin concentration > median (2.8 ± 4.8 vs 4.2 ± 5.7, p = 0.034). Immunohistochemical analyses showed a strong and specific staining of adiponectin in smooth muscle cells in calcified arteries, with a more pronounced expression of adiponectin in early stages of medial calcification. Conclusions Peripheral arterial calcification is positively associated with circulating adiponectin levels in patients with type 2 diabetes, but vascular adiponectin expression is already observed at early stages of calcification. Adiponectin secretion could be a compensatory mechanism against the calcification process. Trial registration DIACART NCT number: NCT02431234. Registered 30 April 2015

International audience

International audience; CA 19-9 (carbohydrate antigen 19-9) is a tumor marker widely used for surveillance of patients with pancreatic cancer. However, even high levels of CA 19-9 may not necessarily be cancer-associated thereby complicating the diagnosis. This case report highlights a transient increase of CA 19-9 in a triple transplanted patient with cystic fibrosis and continuous immunosuppression for 20 years who was under antibiotics. This case emphasizes the need for a balanced interpretation of biological results, especially in cases where many confounding factors are present such as diabetes, chronic renal failure, cystic fibrosis and infections. This case also provides an opportunity to formulate a number of recommendations for the interpretation of tumor marker results in order to avoid long and costly further investigations.

Adults with Prader-Willi syndrome (PWS) have an increased proportion of sc fat mass compared with body mass index (BMI)-matched controls, but whether the genotype influences body composition and metabolic profile remains controversial.To assess body composition and metabolic features in adults with PWS, according to genetic subtype. In addition, the effect of previous GH treatment was assessed. Main Outcomes and Measures: Body composition (Dual Energy X-ray Absorptiometry) and metabolic parameters were compared in PWS adults (mean age, 25.5 ± 8.9 y) with deletion (n = 47) or uniparental disomy (UPD) (n = 26), taking into account GH treatment in childhood and/or adolescence. In subgroups, adipocyte size, fasting total ghrelin levels, and resting energy expenditure were measured, and hyperphagia was assessed by the Dykens Hyperphagia Questionnaire.Body composition (Dual Energy X-ray Absorptiometry) and metabolic parameters were compared in PWS adults (mean age, 25.5 ± 8.9 y) with deletion (n = 47) or uniparental disomy (UPD) (n = 26), taking into account GH treatment in childhood and/or adolescence. In subgroups, adipocyte size, fasting total ghrelin levels, and resting energy expenditure were measured, and hyperphagia was assessed by the Dykens Hyperphagia Questionnaire.In the whole sample, the deletion group had a higher BMI compared with UPD (40.9 ± 11.5 vs 34.6 ± 9.6 kg/mA deletion genotype in adults with PWS is associated with increased BMI. GH treatment in childhood and/or adolescence limits this deleterious phenotypic effect with improved adiposity markers. This study suggests relationships between the molecular phenotype of PWS and adipose tissue development as well as sensitivity to GH.

Few studies have reported reproductive outcomes after breast cancer chemotherapy. The relationship between anti-Müllerian hormone (AMH) concentrations and the occurrence of subsequent pregnancies in women after chemotherapy for breast cancer was investigated. Women aged 18-43 years treated with chemotherapy for invasive breast cancer between May 2005 and January 2011 were retrospectively identified. Exclusion criteria were previous gonadotoxic treatment, oophorectomy or hysterectomy. Measurement of AMH took place before, during chemotherapy and at distant time points after the end of chemotherapy (4 months to 5.5 years). Seventeen out of 134 patients experienced 28 spontaneous pregnancies (median follow-up: 59 months). Neither baseline AMH (divided into quartiles) nor end-of-chemotherapy AMH (detectable versus undetectable) were significantly associated with the occurrence of pregnancy. Chemotherapy regimen with anthracyclines was associated with a greater probability of pregnancy compared with a taxane-containing regimen (hazard ratio 4.75; (95% CI 1.76 to 12.8); P = 0.002). Five-year disease-free survival and overall survival rates were 60% (95% CI: 51 to 70; relapse, n = 48) and 88% (95% CI 82 to 95; deaths, n = 21), respectively. AMH did not predict the occurrence of pregnancy. Additional studies assessing ovarian reserve and reproductive outcomes after breast cancer are required.

Craniopharyngiomas are rare cerebral tumors associated with severe obesity after hypothalamic surgery. A meta-analysis showed significant weight loss at 1 year after bariatric surgery in these patients even though more modest than in common causes of obesity. We hypothesized that this discrepancy could be partly explained by differences in GLP-1 secretion after surgery since patients with craniopharyngioma present a significantly higher degree of insulin resistance and hyperinsulinism than common obese control. We report three cases of bariatric surgery in patients presenting with hypothalamique obesity related to craniopharyngiomas. At 18 months, the mean weight loss was 20 kg with expected insulin resistance decrease. Before surgery, standardized test meal shows abolition of postprandial GLP-1 secretion in all patients with a progressive restoration in the patients with gastric bypass (GBP) surgery.

International audience; Circulating tumor cell (CTC) detection and numeration are becoming part of the common clinical practice, especially for breast, colon, and prostate cancer. However, their paucity in peripheral blood samples is an obstacle for their identification. Several groups have tried to improve CTC recovery rate by developing highly sensitive cellular and molecular detection methods. However, CTCs are still difficult to detect in peripheral blood. Therefore, their recovery rate could be increased by obtaining blood samples from vessels close to the drainage territories of the invaded organ, when the anatomical situation is favorable. This approach has been tested mostly during tumor resection surgery, when the vessels nearest to the tumor are easily accessible. Moreover, radiological (including echo-guided based and endovascular techniques) and/or endoscopic routes could be utilized to obtain CTC samples close to the tumor in a less invasive way than conventional biopsies. The purpose of this article is to summarize the available knowledge on CTC recovery from blood samples collected close to the tumor (i.e., in vessels located in the drainage area of the primary tumor or metastases). The relevance of such an approach for diagnostic and prognostic evaluations will be discussed, particularly for pancreatic ductal adenocarcinoma, colorectal adenocarcinoma, hepatocellular carcinoma, and non-small-cell lung cancer.

Introduction et but de l’etude La voie leptine-melanocortines joue un role-cle dans l’homeostasie energetique. Les variants homozygotes sur les genes de cette voie sont associes a une obesite severe et precoce avec anomalies endocriniennes. Le role des variants heterozygotes sur ces memes genes n’est pas etabli dans l’obesite. Le but de l’etude etait de decrire leur frequence et la relation genotype/phenotype dans une cohorte d’enfants et d’adultes avec obesite severe. Materiel et methodes Le sequencage direct sur au moins un gene de la voie (LEP, LEPR, POMC, PCSK1 et MC4R) a ete realise chez 6347 patients avec obesite severe et/ou precoce. La fonctionnalite des variants a ete determinee a partir des consequences proteiques predites, de 7 outils de prediction, et des etudes fonctionnelles decrites. Le phenotype incluait l’âge de debut d’obesite et sa severite, le comportement alimentaire et les anomalies endocriniennes associees. Le phenotype des sujets porteurs heterozygotes (n = 60 dont 29 enfants) a ete compare a celui des homozygotes (n = 16 dont 4 enfants) mais aussi selon la fonctionnalite des variants et le nombre de variants heterozygotes presents chez un meme patient (variants combines) a la recherche d’un effet cumulatif. Resultats et analyse statistique La frequence des variants homozygotes etait de 0,8 % (n = 26) et des variants heterozygotes de 3,3 % (n = 110) dont 1,7 % de variants heterozygotes avec impact fonctionnel (LEP n = 0/22, LEPR n = 23/40, POMC n = 10/21, PCSK1 n = 23/27). Douze sujets (12 %) etaient porteurs de plusieurs variants heterozygotes (MC4R inclus). Chez les enfants, aucune difference significative n’a ete mise en evidence pour l’âge de debut d’obesite et sa severite entre les porteurs heterozygotes et homozygotes. L’IMC moyen des adultes etait significativement superieur pour les porteurs homozygotes compare a celui des porteurs heterozygotes (IMC 66 vs 53 kg/m2, p = 0,015). De meme, l’âge de debut d’obesite etait plus precoce (0,4 vs 5,4 ans, p Conclusion La presence d’un ou plusieurs variants heterozygotes avec impact fonctionnel sur la voie leptine-melanocortines est associee a une obesite severe et precoce avec parfois des anomalies endocriniennes et donc un phenotype proche de celui des sujets porteurs homozygotes. Ces donnees sont donc en faveur de la recherche systematique de variants sur cette voie cle du controle de la prise alimentaire en cas d’obesite precoce et severe avec ou sans anomalie endocrinienne associee afin de discuter l’indication d’un traitement par agoniste MC4R.

Discipline Clinique. Introduction et but de l’etude La chirurgie bariatrique connait un essor considerable dans le traitement de l’obesite. Les deux interventions de reference sont la Sleeve Gastrectomie (SG) et le Bypass Gastrique Roux-en-Y (RYGB). Une troisieme procedure est de plus en plus realisee en France, il s’agit du bypass gastrique en omega (OLGB) techniquement moins difficile a realiser mais dont on ne sait pas encore clairement si elle est equivalente au RYGB. Le succes du RYGB est en partie associe a un changement des profils de secretion des hormones entero-insulaires, notamment du GLP-1. L’objectif de notre etude est d’explorer les profils de secretion de ces hormones chez des patients operes d’OLGB en les comparant aux profils observes chez des patients operes de RYGB. Materiel et methodes Il s’agit d’une etude clinique : code projet : K171007 J/N° IDRCB : 2017-A02816-47 avec un financement par la fondation ANTADIR (JFN 2017). Au total, il est prevu d’inclure 30 patients non traites par hypoglycemiants a deux ans de leur chirurgie (15 RYGB et 15 OLGB). Des prelevements sanguins a jeun puis apres repas test calibre (a 15, 30, 60, 90 et 120 min) seront realises pour mesurer les taux de glycemie et d’hormones entero-insulaires (insuline, peptide C, glucagon, GLP-1, GIP, GLP-2, glicentine). L’analyse statistique sera faite avec un test non parametrique de Mann Whitney pour comparer les variables cliniques, biologiques et les AUC moyen (Area Under the Curve) pour chaque parametre mesure. Des tests Anova 2way avec correction de Bonferroni permettront de comparer les cinetiques d’evolution des variables cliniques et biologiques. Resultats et analyse statistique Actuellement, nous avons inclus 12 patients operes de OLGB et 6 de RYGB. La perte de poids moyenne n’est pas statistiquement differente entre les deux groupes de patients (p = 0,254). Il en est de meme concernant la moyenne des glycemies a jeun et post repas test et avec les valeurs moyennes des AUC glycemiques similaire (p = 0,958). Les cinetiques de secretions de l’insuline, du peptide C, de la glicentine et du GLP-1 ont ete evaluees chez 4 RYGB et 5 OLGB. Comme attendu, nous observons un pic de secretion postprandiale de ces hormones dans les deux groupes de patients sans difference statistique (p = 0,190 ; p = 0,413 ; p = 0,905 ; p = 1 RYGB). Conclusion Il s’agit de la seule etude clinique ayant analyse les secretions hormonales responsables de l’homeostasie glucidique chez des patients operes de OLGB en les comparant a l’intervention de reference qu’est le RYGB. Nous n’avons pour le moment pas mis en evidence de difference statistique entre les deux interventions. Ces resultats bien que preliminaires montrent que l’OLGB peut permettre de restaurer des secretions de GLP-1 notamment de facon comparable au RYGB.

Discipline Clinique. Introduction et but de l’etude La voie leptine/melanocortines joue un role critique dans le controle hypothalamique de la prise alimentaire. Des mutations sur les genes de cette voie, comme leptine (LEP) et son recepteur (LEPR), proopiomelanocortine (POMC), proconvertase 1 (PCSK1) sont associees a une obesite precoce et severe avec anomalies endocriniennes notamment en cas d’homozygotie. Les mutations du recepteur de type 4 aux melanocortines (MC4R) heterozygotes sont associees a une augmentation du risque d’obesite severe. L’objectif est de decrire la frequence des mutations homozygotes et heterozygotes dans les genes de la voie leptine/melanocortine chez des enfants et adultes obeses consultant dans un centre specialise. Materiel et methodes Les exons codants des genes LEP, LEPR,POMC, PCSK1et MC4R ont ete sequences par la methode SANGER. Les 6100 patients inclus avaient une obesite severe (IMC > 35 kg/m2 pour les adultes et Zscore de l’IMC > + 2,5 DS pour les enfants). MC4R a ete sequence chez 5815 sujets, LEPR chez 1180 patients, LEP chez 800 patients, POMC chez 556 patients et PCSK1 chez 288 patients. Resultats et analyse statistique La frequence des variants homozygotes etait ≤ 1 % avec 13 (1,02 %) variants LEPR (p.C604G, p.L786P, p.H800_N831del, p.Y422H p.T711 N, p.535–1G > A, p.P166CfsX7,p.Met1X), 3 (0,4 %) variants LEP(p.Q55X, p.R105 W, p.V94 M), 1 variant (0,4 %) PCSK1 (c.286–2A > G), 3 variants (0,6 %) POMC (p.R75Profs × 44 ; p.E214G ; p.D53G) et 7 variants (0,12 %) MC4R (p.R165Q, p.S127L, p.C277X, p.V166I, p.C271R, p.I170 V). Les patients homozygotes avaient une obesite precoce debutee avant 3 ans, une hyperphagie majeure dans la petite enfance et d’autres phenotypes notamment endocriniens associes. La frequence des variants heterozygotes etait de 2–3 % pour POMC, MC4R et LEPR alors qu’elle etait inferieure a 2 % pour PCSK1 (1,4 %) et LEP (0,5 %). La presence d’un variant heterozygote avec consequence fonctionnelle dans ces genes etait toujours associee a une obesite debutee avant 10 ans sans anomalie endocrine. Quatre patients etaient porteurs de variants combines heterozygotes sur au moins deux genes de la voie (POMC p.D53G et LEP p.V94 M [n = 1] ; LEPR p.W699 M et LEP p.V94 M [n = 1] ; MC4R p.S58 C et LEPR p.W699 M [n = 2]) avec possible effet cumulatif. Conclusion Ce travail confirme l’implication des variants des genes de la voie leptine/melanocortines dans l’obesite precoce et severe (2 a 3 % des patients avec obesite severe) et est actuellement etendu a d’autres genes modulant cette voie. Ce depistage est critique car aujourd’hui des options therapeutiques efficaces par agoniste MC4R (setmelanotide) existent et permettent de restaurer l’activite de cette voie (Clement et al, Nature Med, 2018). Le developpement d’outils cliniques aidant au diagnostic et de nouveaux tests moleculaires par NGS etendue aux autres genes de la voie permettra de diagnostiquer les patients candidats a cette nouvelle therapeutique.

International audience; CONTEXT: Infrequent mutations have been reported in the leptin receptor (LEPR) gene in humans with morbid obesity and endocrine disorders. However LEPR mutations are rarely examined in large populations from different ethnicities in a given country. OBJECTIVE: We estimated the prevalence of LEPR mutations in French patients with severe obesity and evaluated mutated patients' phenotype. DESIGN AND PATIENTS: We sequenced the LEPR gene in 535 morbidly obese French participants. We conducted clinical investigations to determine whether individuals with a novel shared mutation display particular characteristics relative to obesity history, body composition, hormonal functions, and the outcome of bariatric surgery. RESULTS: We identified 12 patients with a novel LEPR mutation (p.C604G, p.L786P, p.H800_N831del, p.Y422H, p.T711NfsX18, p.535-1G\textgreaterA, p.P166CfsX7). Six unrelated subjects were carriers of the p.P166CfsX7 mutation leading to deletion overlapping exons 6 to 8. All subjects originated from Reunion Island (France). Their clinical features (severe early-onset obesity, food impulsivity, and hypogonadotropic hypogonadism) did not differ from other new LEPR mutation carriers. Results concerning weight loss surgery were inconsistent in homozygous LEPR mutation carriers. Heterozygous LEPR mutation carriers exhibited variable severity of obesity and no endocrine abnormality. CONCLUSION: Among seven newly discovered LEPR mutations in this French obese population, we identified a LEPR frameshift mutation shared by six subjects from Reunion Island. This observation suggests a founder effect in this Indian Ocean island with high prevalence of obesity and supports a recommendation for systematic screening for this mutation in morbidly obese subjects in this population.

Post-bypass postprandial hypoglycemia (PPH) is a frequent complication of Roux-en-Y Gastric Bypass (RYGB) but predictors remain poorly identified and are needed to assess individual risk. After RYGB, exaggerated secretion of glucagon-like peptide-1 (GLP-1) and insulin could lead to PPH, but other proglucagon-derived peptides, including glicentin and glucagon, could also contribute to this phenomenon.To identify biological hypoglycemia in relation to the secretion of proglucagon-derived peptides during a mixed-meal test (MMT) in RYGB patients.University hospital.Twenty RYGB patients reporting symptoms consistent with PPH were examined 36.9 ± 5.1 months after surgery. Plasma levels of glucose, c-peptide, glucagon, GLP-1 and glicentin were assessed before and during MMT. Patients with postprandial hypoglycemia ≤3 mM (54 mg/dL) during MMT were assigned to HYPO group and compared with patients not exhibiting hypoglycemia (NONHYPO group).Seven patients displayed hypoglycemia ≤3 mM (HYPO) during the MMT. Lower fasting glycemia (4.5 mM versus 5.3 mM, P.05) and higher fasting glicentin (22.6 pM versus 14.0 pM, P.05) were observed in HYPO versus NONHYPO patients. Fasting glicentin was inversely correlated with postprandial nadir glucose. Examining the receiver-operating characteristics curve analysis, a cutoff of 17.2 pM for fasting glicentin identified PPH with 85.7% sensitivity and 53.8% specificity. All patients exhibited a similar increase of postprandial GLP-1, glucagon, and glicentin secretions that correlated with each other.These results suggest that fasting glicentin is a potential biomarker to examine in operated-obese patients at risk of developing PPH. Further studies are needed before proposing fasting glicentin as a predictive factor of PPH.

The somatic mutations in the RAS genes (KRAS and NRAS) are widely associated with non-response to immunotherapies targeting the epidermal growth factor receptor in metastatic colorectal cancer. The detection of these mutations is carried out from tissue biopsies and become mandatory to prescribe these treatments. Nethertheless, this analysis is not possible in about 25% of cases and the development of alternative methods is therefore required. Among them, the search for mutations directly in the blood of patients are promising approaches. Circulating tumor cells (CTCs) represent a particularly relevant direct target. These cells, some of them have inducing-metastasis capabilities, have been able to detach themselves from the primary tumor, then migrate and finally enter into the bloodstream. In this sense, they are particularly resistant to physical-chemical and immunological constraints used by the organism to prevent their dissemination. Consequently, they represent a particularly valuable source of information on the most aggressive tumor cells. As a corollary, these cells are very rare requiring particularly highly performant technologies to be detected. In this presentation, we focus mainly on the molecular methods used to detect these mutated RAS cells by analyzing the performance of a solution based on a filtration device followed by detection with digital PCR. Finally, we will discuss the biological significance of these cells before highlighting prospects in colorectal cancer but also in other cancers.

BEAMing polymerase chain reaction (PCR) and digital PCR (dPCR) are used for robust and accurate quantification of nucleic acids. These methods are particularly well suited for the identification of very small fractions (