Jean-Marc Lacorte

Study of anti-Müllerian hormone and its relation to the subsequent probability of pregnancy in 112 patients with systemic lupus erythematosus, exposed or not to cyclophosphamide.

CONTEXT Cyclophosphamide is used for renal and major extrarenal involvement in systemic lupus erythematosus (SLE) and is associated with a risk of premature ovarian failure. There are no data available about the relation between anti-Müllerian hormone (AMH) serum levels and the probability of subsequent pregnancy in SLE patients. OBJECTIVE We analyzed AMH levels and the probability of pregnancy in SLE women exposed to cyclophosphamide. DESIGN AND SETTING We conducted a matched cohort study in referral centers for SLE. PATIENTS Fifty-six cyclophosphamide-exposed SLE women younger than 40 years of age and 56 control SLE women matched for age within 6 months participated in the study. MAIN OUTCOME MEASURES AMH was measured in samples from the PLUS study (ClinicalTrials.gov no. NCT00413361). All patients were interviewed in May 2012 regarding their obstetric status. RESULTS The mean age ± SD of the 112 patients was 31.6 ± 5.8 years. The mean AMH level was low (1.21 ± 1.01 ng/mL) and was significantly lower in patients exposed to cyclophosphamide (P = .03) and in patients older than 30 years (P = .02). During a median follow-up (interval between sampling and the interview) period of 4.2 (range, 2.5-4.8) years, 38 patients sought to become pregnant, and 32 (84.2%) succeeded. In the univariate analysis, the risk of failure was associated with cumulative cyclophosphamide dose (P = .007) and older age (P = .02), but not with AMH. CONCLUSION We confirmed that AMH levels are low in SLE patients and decrease significantly with age and cyclophosphamide exposure. Nonetheless, the risk of failure to conceive was low and was predicted by cyclophosphamide exposure and age, but not by AMH levels.

Droplet digital PCR of circulating tumor cells from colorectal cancer patients can predict KRAS mutations before surgery

In colorectal cancer (CRC), KRAS mutations are a strong negative predictor for treatment with the EGFR‐targeted antibodies cetuximab and panitumumab. Since it can be difficult to obtain appropriate tumor tissues for KRAS genotyping, alternative methods are required. Circulating tumor cells (CTCs) are believed to be representative of the tumor in real time. In this study we explored the capacity of a size‐based device for capturing CTCs coupled with a multiplex KRAS screening assay using droplet digital PCR (ddPCR). We showed that it is possible to detect a mutant ratio of 0.05% and less than one KRAS mutant cell per mL total blood with ddPCR compared to about 0.5% and 50–75 cells for TaqMeltPCR and HRM. Next, CTCs were isolated from the blood of 35 patients with CRC at various stage of the disease. KRAS genotyping was successful for 86% (30/35) of samples with a KRAS codon 12/13 mutant ratio of 57% (17/30). In contrast, only one patient was identified as KRAS mutant when size‐based isolation was combined with HRM or TaqMeltPCR. KRAS status was then determined for the 26 available formalin‐fixed paraffin‐embedded tumors using standard procedures. The concordance between the CTCs and the corresponding tumor tissues was 77% with a sensitivity of 83%. Taken together, the data presented here suggest that is feasible to detect KRAS mutations in CTCs from blood samples of CRC patients which are predictive for those found in the tumor. The minimal invasive nature of this procedure in combination with the high sensitivity of ddPCR might provide in the future an opportunity to monitor patients throughout the course of disease on multiple levels including early detection, prognosis, treatment and relapse as well as to obtain mechanistic insight with respect to tumor invasion and metastasis.

The Role of BEAMing and Digital PCR for Multiplexed Analysis in Molecular Oncology in the Era of Next-Generation Sequencing

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 (<1%) of variant copies such as the presence of mutant genes in a predominantly wild-type background. BEAMing and dPCR are increasingly used in diverse fields including bacteriology, virology, non-invasive prenatal testing, and oncology, in particular for the molecular analysis of liquid biopsies. In this review, we present the principles of BEAMing and dPCR as well as the trends of future technical development, focusing on the possibility of developing multiplexed mutation analysis. Finally, we will discuss why such techniques will remain useful despite the ever-decreasing costs and increased automatization of next-generation sequencing (NGS), using molecular characterization of cancer cells as an example.

Vitamin D Status, Insulin Resistance, Leptin-To-Adiponectin Ratio in Adolescents: Results of a 1-Year Lifestyle Intervention

AIM: We aimed to study the relationships between circulating 25-hydroxyvitamin D [25(OH)D], insulin resistance and leptin-to-adiponectin (L/A) ratio in Guadeloupean children and adolescents and to analyse the changes in 25(OH)D levels after a 1-year lifestyle intervention program. METHODS: 25(OH)D concentrations were measured via a chemiluminescence assay. Cardiometabolic risk factors, homoeostasis model assessment of insulin resistance (HOMA-IR), and adipokines were measured. The lifestyle intervention included dietary counselling, regular physical activity. RESULTS: Among 117 girls and boys (11–15 years old, 31.6% obese), 40% had vitamin D deficiency (25(OH)D levels < 20 ng/mL). With linear regression models where 25(OH)D and HOMA-IR acted as independent variables and age, sex, BMI, L/A ratio as covariates, 25(OH)D was significantly associated with HOMA-IR alone (P = 0.036). HOMA-IR was also associated with BMI z-score ≥ 2, L/A ratio and an interaction term BMI z-score ≥ 2*L/A ratio (P < 0.001 for all). After one year, in 78 children/adolescent, mean serum 25(OH)D increased significantly from 21.4 ± 4.9 ng/mL at baseline to 23.2 ± 6.0 after 1 year; P = 0.003 whereas BMI z-score, HOMA-IR and L/A ratio decreased significantly (P = 0.003, P < 0.001 and P = 0.012; respectively). CONCLUSION: The association between 25(OH)D and HOMA-IR, independently of obesity and the high prevalence of vitamin D deficiency should be considered in order to prevent the later incidence of T2DM. A healthy lifestyle including non-sedentary and outdoor activities could be a way for improving vitamin D status.

Randomized controlled trial of a 12-month computerized mindfulness-based intervention for obese patients with binge eating disorder: The MindOb study protocol

BACKGROUND Mindfulness-based interventions for healthy behaviors such as exercise and dietary modifications have aroused growing interest. This study aims to test the effectiveness of a mindfulness-based intervention for the reduction of impulsive eating and the improvement of motivation to exercise among obese individuals. METHODS One-hundred and twenty obese outpatients, aged 18 to 65years, diagnosed with a binge eating disorder, will be randomly assigned to one of the three following groups: mindfulness practice, sham meditation, or treatment as usual control. The tested intervention consists of a 1-year computerized mindfulness-based program. Mindfulness sessions are audio recordings that the patients are asked to listen to, 10min every day. Self-reported questionnaires measuring impulsive eating, motivation to exercise, physical activity level, mood, and mindfulness skills are filled in at baseline, 1, 6, and 12months. Physical activity, calories consumption, and biomarkers are measured with more objective measurement tools at baseline, 6months and 12months. CONCLUSION Mindfulness, as both a de-automation element and as a moderator of motivation to exercise, can lead to the reduction of impulsive eating and also to an increase in levels of physical activity. These effects could cause weight loss in obese patients suffering from binge eating disorder. TRIAL REGISTRATION clinicaltrials.gov: NCT02571387.

Fasting levels of glicentin are higher in Roux-en-Y gastric bypass patients exhibiting postprandial hypoglycemia during a meal test

BACKGROUND 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. OBJECTIVES To identify biological hypoglycemia in relation to the secretion of proglucagon-derived peptides during a mixed-meal test (MMT) in RYGB patients. SETTING University hospital. METHODS 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). RESULTS 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. CONCLUSIONS 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.

Transient increase of CA 19–9 serum concentrations in a liver transplant recipient with cystic fibrosis and hepatic abscess: a case report and brief literature review

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.

Détection des mutations RAS dans les cellules tumorales circulantes : applications au cancer colorectal et perspectives

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.