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Impaired skeletal muscle mitochondrial fatty acid oxidation (mFAO) has been implicated in the etiology of insulin resistance. Carnitine palmitoyltransferase-1 (CPT1) is a key regulatory enzyme of mFAO whose activity is inhibited by malonyl-CoA, a lipogenic intermediate. Whereas increasing CPT1 activity in vitro has been shown to exert a protective effect against lipid-induced insulin resistance in skeletal muscle cells, only a few studies have addressed this issue in vivo. We thus examined whether a direct modulation of muscle CPT1/malonyl-CoA partnership is detrimental or beneficial for insulin sensitivity in the context of diet-induced obesity. By using a Cre-LoxP recombination approach, we generated mice with skeletal muscle-specific and inducible expression of a mutated CPT1 form (CPT1mt) that is active but insensitive to malonyl-CoA inhibition. When fed control chow, homozygous CPT1mt transgenic (dbTg) mice exhibited decreased CPT1 sensitivity to malonyl-CoA inhibition in isolated muscle mitochondria, which was sufficient to substantially increase ex vivo muscle mFAO capacity and whole body fatty acid utilization in vivo. Moreover, dbTg mice were less prone to high-fat/high-sucrose (HFHS) diet-induced insulin resistance and muscle lipotoxicity despite similar body weight gain, adiposity, and muscle malonyl-CoA content. Interestingly, these CPT1mt-protective effects in dbTg-HFHS mice were associated with preserved muscle insulin signaling, increased muscle glycogen content, and upregulation of key genes involved in muscle glucose metabolism. These beneficial effects of muscle CPT1mt expression suggest that a direct modulation of the malonyl-CoA/CPT1 partnership in skeletal muscle could represent a potential strategy to prevent obesity-induced insulin resistance. [ABSTRACT FROM AUTHOR]

Background:YS110 is a humanised IgG1 monoclonal antibody with high affinity to the CD26 antigen. YS110 demonstrated preclinical anti-tumour effects without significant side effects.Methods:This FIH study was designed to determine the maximal tolerated dose (MTD) and recommended phase 2 dose (RP2D) to assess the tolerance, pharmacokinetics (PK) and pharmacodynamics profiles of YS110 and preliminary efficacy. YS110 were initially administered intravenously once every 2 weeks (Q2W) for three doses and then, based on PK data, once every week (Q1W) for five doses in patients with CD26-expressing solid tumours.Results:Thirty-three patients (22 mesothelioma) received a median of 3 (range 1-30) YS110 infusions across six dose levels (0.1-6 mg kg-1). MTD was not reached and two dose-limiting toxicities (infusion hypersensitivity reactions) led to the institution of a systemic premedication. Low-grade asthenia (30.3%), hypersensitivity (27.3%), nausea (15.2%), flushing (15.2%), chills (12.1%) and pyrexia (12.1%) were reported as ADRs. Pharmacokinetic parameters (AUC and Cmax) increased in proportion with the dose. sCD26/DPPIV assays indicated CD26 modulation. Prolonged stable diseases were observed in 13 out of 26 evaluable patients.Conclusions:YS110 is well tolerated up to 6 mg kg-1 Q1W, which has been defined as the RP2D, with encouraging prolonged disease stabilisations observed in a number of patients with advanced/refractory mesothelioma. [ABSTRACT FROM AUTHOR]

Background: Thymidine phosphorylase (TP), encoded by the TYMP gene, is a cytosolic enzyme essential for the nucleotide salvage pathway. TP catalyzes the phosphorylation of the deoxyribonucleosides, thymidine and 2′-deoxyuridine, to thymine and uracil. Biallelic TYMP variants are responsible for Mitochondrial NeuroGastroIntestinal Encephalomyopathy (MNGIE), an autosomal recessive disorder characterized in most patients by gastrointestinal and neurological symptoms, ultimately leading to death. Studies on the impact of TYMP variants in cellular systems with relevance to the organs affected in MNGIE are still scarce and the role of TP in adipose tissue remains unexplored. Methods: Deep phenotyping was performed in three patients from two families carrying homozygous TYMP variants and presenting with lipoatrophic diabetes. The impact of the loss of TP expression was evaluated using a CRISPR-Cas9-mediated TP knockout (KO) strategy in human adipose stem cells (ASC), which can be differentiated into adipocytes in vitro. Protein expression profiles and cellular characteristics were investigated in this KO model. Results: All patients had TYMP loss-of-function variants and first presented with generalized loss of adipose tissue and insulin-resistant diabetes. CRISPR-Cas9-mediated TP KO in ASC abolished adipocyte differentiation and decreased insulin response, consistent with the patients' phenotype. This KO also induced major oxidative stress, altered mitochondrial functions, and promoted cellular senescence. This translational study identifies a new role of TP by demonstrating its key regulatory functions in adipose tissue. Conclusions: The implication of TP variants in atypical forms of monogenic diabetes shows that genetic diagnosis of lipodystrophic syndromes should include TYMP analysis. The fact that TP is crucial for adipocyte differentiation and function through the control of mitochondrial homeostasis highlights the importance of mitochondria in adipose tissue biology. [ABSTRACT FROM AUTHOR]

Background and objectives: More and more anticancer chemotherapies are now available as oral formulations. This relatively new route of administration in oncology leads to problems with patient education and non-compliance. The aim of this study was to explore the performances of the 'inverse problem', namely, estimation of compliance from pharmacokinetics. For this purpose, we developed and evaluated a method to estimate patient compliance with an oral chemotherapy in silico (i) from an a priori population pharmacokinetic model; (ii) with limited optimal pharmacokinetic information collected on day 1; and (iii) from a single pharmacokinetic sample collected after multiple doses. Methods: Population pharmacokinetic models, including estimation of all fixed and random effects estimated on a prior dataset, and sparse samples taken after the first dose, were combined to provide the individual POSTHOC Bayesian pharmacokinetic parameter estimates. Sampling times on day 1 were chosen according to a D-optimal design. Individual pharmacokinetic profiles were simulated according to various dose-taking scenarios. To characterize compliance over the n previous dosing times (supposedly known without error), 2n different compliance scenarios of doses taken/not taken were considered. The observed concentration value was compared with concentrations predicted from the model and each compliance scenario. To discriminate between different compliance profiles, we used the Euclidean distance between the observed pharmacokinetic values and the predicted values simulated without residual errors. This approach was evaluated in silico and applied to imatinib and capecitabine, the pharmacokinetics of which are described in the literature, and which have quite different pharmacokinetic characteristics (imatinib has an elimination half-life of 17 hours, and α-fluoro-β-alanine [FBAL], the metabolite of capecitabine, has an elimination half-life of 3 hours). 1000 parameter sets were drawn according to population distributions, and concentration values were simulated at several timepoints under various compliance patterns to compare with the predicted ones. In addition, several simulation scenarios were run in order to explore the impact of the quality of the error model, interoccasion variability (IOV), error in the number of pills taken, and the performance of the compliance estimation method. Results: The best compliance estimate was obtained with pharmacokinetic samples taken 5 hours after the last dose. Performance of the method varied between simulation scenarios. In both the imatinib and capecitabine basic simulations, patient compliance was correctly estimated on the two last scheduled doses (with better results for imatinib). The magnitude of the error model also had a great impact on the quality of the compliance estimate. Conclusions: We highlight the effect of three parameters on the quality of compliance estimates based on limited pharmacokinetic information: the plasma elimination half-life, interdose interval and magnitude of the error model. Nevertheless, the pharmacokinetic method is not informative enough and should be used with electronic monitoring, which provides additional information on compliance. Our method will be used in a future phase IV clinical trial where the relationships between compliance, efficacy and tolerability will be assessed. [ABSTRACT FROM AUTHOR]

Background: Thymidine phosphorylase (TP), encoded by the TYMP gene, is a cytosolic enzyme essential for the nucleotide salvage pathway. TP catalyzes the phosphorylation of the deoxyribonucleosides, thymidine and 2'-deoxyuridine, to thymine and uracil. Biallelic TYMP variants are responsible for Mitochondrial NeuroGastroIntestinal Encephalomyopathy (MNGIE), an autosomal recessive disorder characterized in most patients by gastrointestinal and neurological symptoms, ultimately leading to death. Studies on the impact of TYMP variants in cellular systems with relevance to the organs affected in MNGIE are still scarce and the role of TP in adipose tissue remains unexplored.Methods: Deep phenotyping was performed in three patients from two families carrying homozygous TYMP variants and presenting with lipoatrophic diabetes. The impact of the loss of TP expression was evaluated using a CRISPR-Cas9-mediated TP knockout (KO) strategy in human adipose stem cells (ASC), which can be differentiated into adipocytes in vitro. Protein expression profiles and cellular characteristics were investigated in this KO model.Results: All patients had TYMP loss-of-function variants and first presented with generalized loss of adipose tissue and insulin-resistant diabetes. CRISPR-Cas9-mediated TP KO in ASC abolished adipocyte differentiation and decreased insulin response, consistent with the patients' phenotype. This KO also induced major oxidative stress, altered mitochondrial functions, and promoted cellular senescence. This translational study identifies a new role of TP by demonstrating its key regulatory functions in adipose tissue.Conclusions: The implication of TP variants in atypical forms of monogenic diabetes shows that genetic diagnosis of lipodystrophic syndromes should include TYMP analysis. The fact that TP is crucial for adipocyte differentiation and function through the control of mitochondrial homeostasis highlights the importance of mitochondria in adipose tissue biology. [ABSTRACT FROM AUTHOR]

The relationship between the hypothalamo-pituitary-gonadal (HPG) axis and the hypothalamo-pituitary-adrenal (HPA) axis has been well documented in the rat. In most cases, a negative coupling was observed and an inhibitory effect of the HPA axis upon the HPG was shown. In the female rat, a marked circadian rhythm of corticosterone plasma values is observed during each day of the estrous cycle, with maximal values around 08:00 p.m. The preovulatory luteinizing hormone (LH) surge also occurs at 08:00 p.m. on the day of proestrus. Here we measured circadian variations of plasma cortisol in humans in relation with the time of initiation of the preovulatory LH surge. Blood samples were taken at 08:00 a.m., 12:00 a.m., 04:00 p.m., 08:00 p.m., 12:00 p.m., and 04:00 a.m. from 19 subjects for 4 consecutive days, once 17β-estradiol (E[sub 2] ) values reached 125 pg/ml (days 7–10 of the menstrual cycle). Serum E[sub 2] and LH determinations were performed by microparticle enzyme immunoassays. Serum progesterone and plasma cortisol determinations were made using RIA methods. For plasma cortisol values, a marked circadian rhythm, with 2- to 3-fold higher values during the morning than during the afternoon, was almost identical before, during and after the LH surge. However, values were generally higher during the follicular phase than during the luteal phase. Maximum cortisol values occurred between 04:00 and 08:00 a.m. and minimal cortisol values between 04:00 and 08:00 p.m. Initiation of the LH surge (50% over the mean of previous values) occurred at 04:00 a.m. (20% of the cases) or at 08:00 a.m. (80% of the cases). There was a strong coupling between the onset of the surge and the acrophase of the cortisol circadian rhythm: maximal cortisol plasma values were seen at 04:00 a.m. when the LH preovulatory surge started at 04:00 a.m. and 08:00 a.m. when it started at 08:00 a.m. The present results show that the positive coupling documented in the female rat between the HPA and the HPG axis at the time of preovulatory LH surge is also present during the menstrual cycle in the human.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

These studies investigated the role of substance P (SP) in the regulation of the hypothalamic-pituitary-ovarian axis in cynomolgus monkeys with normal menstrual cycles. Plasma concentrations of SP were determined in blood samples taken every morning in normally menstruating cynomolgus monkeys throughout the menstrual cycle. There was a significant decreasing linear trend of SP during the follicular phase (cycle day –13 to day 0) and a significant inverse relationship between SP plasma values and plasma 17β-estradiol (E[sub 2] ) values from day –13 to day 0 of the adjusted cycle. Correspondingly, SP area under the curve was significantly greater during the follicular phase than the luteal phase. In a second experiment, plasma concentrations of E[sub 2] , luteinizing hormone (LH), follicle-stimulating hormone (FSH) and progesterone and length of cycles were measured after five daily intragastric administrations (10 mg/kg) of an NK[sub 1] receptor (SP receptor) antagonist (RPR 100893; 10 mg/kg) initiated after serum E[sub 2] concentrations had exceeded 125 pg/ml. There was a statistically significant reduction in the amplitude (41% of control) and the area under the curve (37% of control) of the preovulatory LH surge. In addition, there was a reduction of the duration of the LH surge (3 ± 0.1 days in controls vs. 2.1 ± 0.2 days in treated animals). The present results show for the first time that there are significant variations in plasma levels of SP, with a strong negative correlation with serum levels of E[sub 2] during the follicular phase of the cynomolgus monkey, and that endogenous SP has a potentiating role in the interactive hypothalamo-anterior-pituitary mechanisms which lead to the preovulatory LH and FSH surges during the menstrual cycle in the monkey.Copyright © 2000 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Introduction: A patient education program has been developed in the field of cancer for supporting cancer patients undergoing oral anticancer therapies. Its implementation was tested in 3 different settings. The objectives of this study were to 1) identify barriers and facilitators for implementing the patient education program, 2) identify practices encouraging or hindering implementation and 3) produce recommendations for its dissemination. Methods: Twenty semi-structured interviews were conducted with caregivers from all three establishments. Results: The main factors associated with successful implementation were as follows: prescribers' representations on patient education, considered of low value; on oral anticancer therapies, considered too dangerous to be handled by the patient him/herself, the indefinite legitimacy of certain professions in charge of patient education programs; patients' engagement in their care pathway and provision of caregivers. Conclusion: Recommendations include developing patient education culture within the environment of the medical doctors' curriculum, to consider contextual, pre-existing cooperative units for implementing patient education, to systematically send patients to patient education programs without practicing triage. Successful implementation of patient education critically depends on the prescribing physicians' perceived value of patient education. Patient education should become mandatory, integrated as part of the cancer care pathway. Physicians lack the necessary time and/or means to assess patients' capacity for engagement, without adequate strategies for their support. Therefore, physicians should systematically refer all patients to patient education, where nurses can tailor their coaching of cancer patients. Trial Registration: The study protocol was approved by the IRB SUD EST I (N° EudraCT: 2016-A00113-48). All participants were given written and verbal information about the study and gave informed consent to participate. [ABSTRACT FROM AUTHOR]

Hyperosmotic conditions are associated to several pathological states. In this article, we evaluate the consequence of hyperosmotic medium on cellular energy metabolism. We demonstrate that exposure of cells to hyperosmotic conditions immediately reduces the mitochondrial oxidative phosphorylation rate. This causes an increase in glycolysis, which represses further respiration. This is known as the Warburg or Crabtree effect. In addition to aerobic glycolysis, we observed two other cellular responses that would help to preserve cellular ATP level and viability: A reduction in the cellular ATP turnover rate and a partial mitochondrial uncoupling which is expected to enhance ATP production by Krebs cycle. The latter is likely to constitute another metabolic adaptation to compensate for deficient oxidative phosphorylation that, importantly, is not dependent on glucose. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the OCTO clinical study was to measure patients' adherence to capecitabine-based treatment.Methods: A cohort of ambulatory patients treated with capecitabine monotherapy for either locally advanced or metastatic, breast or colorectal cancer was monitored for 6 cycles. Adherence was assessed in all patients by self-completed questionnaires on disease, pill-count and pharmacological dosage of FBAL (metabolite of capecitabine); and in half of the cohort by electronic medication event monitoring systems (MEMS™) recording the opening times of the device.Results: Forty patients were enrolled between November 2008 and September 2011 and treated by capecitabine for an average of 4.75 cycles (range 1-6). Hand-foot syndrome (HFS) was the most frequently reported toxicity (35% patients), and to a lesser extent fatigue and/or asthenia (21%), nausea and/or vomiting (13%) and diarrhea (11%). In the MEMS™ cohort, 20 patients were included. Patients' adherence was excellent with very few missing occasions (23/2272 records). Close analysis of MEMS™ data revealed unexpected medication patterns, such as patients taking extra days of medication beyond planned cycle, patients taking extra doses per day and patients missing a day of dosing and "compensating" by taking extra the following day (N = 7, 18%). A trend was found between over-adherence and high-grade toxicity (grades 3 and/or 4): OR 4.74 [0.65-45.2], p = 0.13 and higher AUC (p = 0.16). There was a trend towards increased AUC of FBAL in over-adherent patients (p = 0.16).Conclusion: Adherence to oral anticancer chemotherapy was found excellent in this population suggesting over-adherence to capecitabine and potential safety implications for outpatients' drugs. [ABSTRACT FROM AUTHOR]

Background: YS110 is a humanised IgG1 monoclonal antibody with high affinity to the CD26 antigen. YS110 demonstrated preclinical anti-tumour effects without significant side effects.Methods: This FIH study was designed to determine the maximal tolerated dose (MTD) and recommended phase 2 dose (RP2D) to assess the tolerance, pharmacokinetics (PK) and pharmacodynamics profiles of YS110 and preliminary efficacy. YS110 were initially administered intravenously once every 2 weeks (Q2W) for three doses and then, based on PK data, once every week (Q1W) for five doses in patients with CD26-expressing solid tumours.Results: Thirty-three patients (22 mesothelioma) received a median of 3 (range 1-30) YS110 infusions across six dose levels (0.1-6 mg kg-1). MTD was not reached and two dose-limiting toxicities (infusion hypersensitivity reactions) led to the institution of a systemic premedication. Low-grade asthenia (30.3%), hypersensitivity (27.3%), nausea (15.2%), flushing (15.2%), chills (12.1%) and pyrexia (12.1%) were reported as ADRs. Pharmacokinetic parameters (AUC and Cmax) increased in proportion with the dose. sCD26/DPPIV assays indicated CD26 modulation. Prolonged stable diseases were observed in 13 out of 26 evaluable patients.Conclusions: YS110 is well tolerated up to 6 mg kg-1 Q1W, which has been defined as the RP2D, with encouraging prolonged disease stabilisations observed in a number of patients with advanced/refractory mesothelioma. [ABSTRACT FROM AUTHOR]

A long-standing paradox in the pathophysiology of metabolic diseases is the selective insulin resistance of the liver. It is characterized by a blunted action of insulin to reduce glucose production, contributing to hyperglycemia, while de novo lipogenesis remains insulin sensitive, participating in turn to hepatic steatosis onset. The underlying molecular bases of this conundrum are not yet fully understood. Here, we established a model of selective insulin resistance in mice by silencing an inhibitor of insulin receptor catalytic activity, the growth factor receptor binding protein 14 (Grb14) in liver. Indeed, Grb14 knockdown enhanced hepatic insulin signaling but also dramatically inhibited de novo fatty acid synthesis. In the liver of obese and insulin-resistant mice, downregulation of Grb14 markedly decreased blood glucose and improved liver steatosis. Mechanistic analyses showed that upon Grb14 knockdown, the release of p62/sqstm1, a partner of Grb14, activated the transcription factor nuclear factor erythroid-2-related factor 2 (Nrf2), which in turn repressed the lipogenic nuclear liver X receptor (LXR). Our study reveals that Grb14 acts as a new signaling node that regulates lipogenesis and modulates insulin sensitivity in the liver by acting at a crossroad between the insulin receptor and the p62-Nrf2-LXR signaling pathways. [ABSTRACT FROM AUTHOR]

Background: Numerous oral anticancer chemotherapies are available. Non-adherence or over-adherence to these chemotherapies can lead to lowered efficacy and increased risk of adverse events. The objective of this study was to identify patients' adherence profiles using a qualitative-quantitative method. Methods: A capecitabine treatment was initiated for 38 patients with advanced breast or colorectal cancer. At inclusion, information on patients' beliefs was reported using a questionnaire. Later, Information on patients' relation to treatment was obtained from a sub-group during an interview with a sociologist. Questionnaires were analyzed using Multiple Classification Analysis to cluster patients. Treatment adherence was evaluated by an electronic medication event monitoring systems (MEMS caps) and then correlated with patient clusters. Interviews were analyzed to complete and explain results. Results: 38 patients were enrolled between 2008 and 2011 and completed the questionnaire. Twenty had adherence measured with MEMS caps all along treatment. Between 4 and 6 months after inclusion, 16 patients were interviewed. Patient profile B (retired, with a regular life, surrounded by a relative's attention to drug adherence, with a low educational level) was statistically associated with adequate adherence (p = 0.049). A tendency for lower adherence was observed among more highly educated patients with an irregular, active life (NS). All patients taking capecitabine demonstrated a risk of over-adherence, potentiating side effects. Conclusions: These encouraging primary results suggest that further studies should be undertaken and that educational programs tailored to patient profiles should be evaluated to enhance adherence for those who need it and to empower all patients to manage treatment side effects. [ABSTRACT FROM AUTHOR]

Adult skeletal muscle is a dynamic, remarkably plastic tissue, which allows myofibers to switch from fast/glycolytic to slow/oxidative types and to increase mitochondrial fatty acid oxidation (mFAO) capacity and vascularization in response to exercise training. mFAO is the main muscle energy source during endurance exercise, with carnitine palmitoyltransferase 1 (CPT1) being the key regulatory enzyme. Whether increasing muscle mFAO affects skeletal muscle physiology in adulthood actually remains unknown. To investigate this, we used in vivo electrotransfer technology to express in mouse tibialis anterior (TA), a fast/glycolytic muscle, a mutated CPT1 form (CPT1mt) that is active but insensitive to malonyl-CoA, its physiologic inhibitor. In young (2-mo-old) adult mice, muscle CPT1mt expression enhanced mFAO (+40%), but also increased the percentage of oxidative fibers (+28%), glycogen content, and capillary-to-fiber density (+45%). This CPT1mt-induced muscle remodeling, which mimicked exercise-induced oxidative phenotype, led to a greater resistance to muscle fatigue. In the context of aging, characterized by sarcopenia and reduced oxidative capacity, CPT1mt expression in TAs from aged (20-mo-old) mice partially reversed aging-associated sarcopenia and fiber-type transition, and increased muscle capillarity. These findings provide evidence that mFAO regulates muscle phenotype and may be a potential target to combat age-related decline in muscle function. [ABSTRACT FROM AUTHOR]

Background Drug–drug interactions (DDIs) may occur with investigational drugs and affect patient safety, trial outcomes, and drug development. A list of preferred drugs with minimal risks of DDIs for treatment of symptoms or comorbidities frequently encountered by cancer patients would be helpful. Methods We reviewed the literature to assess DDIs reported for the main drugs available for treatment of symptoms/comorbidities frequently encountered by cancer patients. Reviews and relevant original articles cited were retrieved and analyzed, and the following data were collected and double-checked: pharmacological properties; effects, if any, of drugs on CYP enzymes, membrane transporters, and QT interval; and involvement in significant DDIs. Results A list of preferred drugs with minimal risks of DDIs was compiled. Conclusion Acknowledging for heterogeneity in data sources, prevention of unexpected DDIs during clinical trials may be improved by using this list of preferred drugs for the management of study patient's symptoms. [ABSTRACT FROM AUTHOR]

Background: Numerous oral anticancer chemotherapies are available. Non-adherence or over-adherence to these chemotherapies can lead to lowered efficacy and increased risk of adverse events. The objective of this study was to identify patients’ adherence profiles using a qualitative–quantitative method. Methods: A capecitabine treatment was initiated for 38 patients with advanced breast or colorectal cancer. At inclusion, information on patients’ beliefs was reported using a questionnaire. Later, Information on patients’ relation to treatment was obtained from a sub-group during an interview with a sociologist. Questionnaires were analyzed using Multiple Classification Analysis to cluster patients. Treatment adherence was evaluated by an electronic medication event monitoring systems (MEMS caps) and then correlated with patient clusters. Interviews were analyzed to complete and explain results. Results: 38 patients were enrolled between 2008 and 2011 and completed the questionnaire. Twenty had adherence measured with MEMS caps all along treatment. Between 4 and 6 months after inclusion, 16 patients were interviewed. Patient profile B (retired, with a regular life, surrounded by a relative’s attention to drug adherence, with a low educational level) was statistically associated with adequate adherence (p = 0.049). A tendency for lower adherence was observed among more highly educated patients with an irregular, active life (NS). All patients taking capecitabine demonstrated a risk of over-adherence, potentiating side effects. Conclusions: These encouraging primary results suggest that further studies should be undertaken and that educational programs tailored to patient profiles should be evaluated to enhance adherence for those who need it and to empower all patients to manage treatment side effects. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H 2 S) is the third gasotransmitter discovered. Sulfide shares with the two others (NO and CO) the same inhibiting properties towards mitochondrial respiration. However, in contrast with NO or CO, sulfide at concentrations lower than the toxic (μM) level is an hydrogen donor and a substrate for mitochondrial respiration. This is due to the activity of a sulfide quinone reductase found in a large majority of mitochondria. An ongoing study of the metabolic state of liver in obese patients allowed us to evaluate the sulfide oxidation capacity with twelve preparations of human liver mitochondria. The results indicate relatively high rates of sulfide oxidation with a large variability between individuals. These observations made with isolated mitochondria appear in agreement with the main characteristics of sulfide oxidation as established before with the help of cellular models. [ABSTRACT FROM AUTHOR]

Cancer cells tilt their energy production away from oxidative phosphorylation (OXPHOS) toward glycolysis during malignant progression, even when aerobic metabolism is available. Reversing this phenomenon, known as the Warburg effect, may offer a generalized anticancer strategy. In this study, we show that overexpression of the mitochondrial membrane transport protein UCP2 in cancer cells is sufficient to restore a balance toward oxidative phosphorylation and to repress malignant phenotypes. Altered expression of glycolytic and oxidative enzymes mediated the effects of this metabolic shift. Notably, UCP2 overexpression increased signaling from the master energy-regulating kinase, adenosine monophosphate-activated protein kinase, while downregulating expression of hypoxia-induced factor. In support of recent new evidence about UCP2 function, we found that UCP2 did not function in this setting as a membrane potential uncoupling protein, but instead acted to control routing of mitochondria substrates. Taken together, our results define a strategy to reorient mitochondrial function in cancer cells toward OXPHOS that restricts their malignant phenotype. [ABSTRACT FROM AUTHOR]

Background: To reduce the occurrence of medication errors, a systemic approach was developed combining anti-neoplastic medication error reviews and morbidity and mortality conferences (M&MCs). We report the first experience of implementing this strategy in oncology. Methods: The case reports submitted to combined reviews were prepared by physicians and pharmacists, and medication error(s) were described and chronological and root-cause analyses were performed. Results: Ten combined reviews were conducted, which involved the departments of haematology, medical oncology, pneumology, gastroenterology and clinical oncology pharmacy. A total of 91 errors were analysed, of which 3 had reached the patient. Thirty-four corrective actions were proposed; 53% consisted of changes in practice, 35% in procedural reminders and 12% in on-ward education sessions. Conclusions: The combination of medication error reviews and M&MCs appears to be an efficient means of improving cancer patient safety and personnel proficiency. This multidisciplinary work is indispensable to improve future patient management through the critical analysis of past medical errors. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Even though anticancer drugs are prepared in dedicated pharmaceutical units, nurses remain exposed to cytotoxic agents during administration to patients. Objective: The aim of this study was to assess this occupational exposure during the intravenous line- purging procedure at the patient's bedside before administration in oncology departments. Methods: This prospective study was conducted over a 4-week period in the hematology and oncology departments at a university hospital. Amounts of doxorubicin and cyclophosphamide on the surface of nurses' gloves were measured after the intravenous line purge of the infusion bag and the connection to the patient. For this purpose, gloves were washed with sterile water, following a validated procedure. Quantification of the 2 drugs into the water was performed using LC-MS/MS. Results: After 59 chemotherapy administrations, 30.5% of gloves were contaminated. Despite extremely low volumes of contamination (0.08-6.28 μL), amounts collected ranged from 190 to 2500 ng per pair of gloves that tested positive for doxorubicin (median, 1600 ng) and from 130 to 32,600 ng with cyclophosphamide (median, 2700 ng). Conclusions: The intravenous line purge preceding antineoplastic infusion bag administration is a potential source of contamination in nurses. Contaminations appear to be invisible but frequent (in >30% of cases). Therefore, intravenous line purging performed under appropriately safe conditions should be mandated in pharmaceutical units dedicated to injectable-drug preparation. This measure should be included as a standard hospital practice as a matter of urgency. [ABSTRACT FROM AUTHOR]

Background & Aims: Despite major public health concern, therapy for non-alcoholic fatty liver, the liver manifestation of the metabolic syndrome often associated with insulin resistance (IR), remains elusive. Strategies aiming to decrease liver lipogenesis effectively corrected hepatic steatosis and IR in obese animals. However, they also indirectly increased mitochondrial long-chain fatty acid oxidation (mFAO) by decreasing malonyl-CoA, a lipogenic intermediate, which is the allosteric inhibitor of carnitine palmitoyltransferase 1 (CPT1A), the key enzyme of mFAO. We thus addressed whether enhancing hepatic mFAO capacity, through a direct modulation of liver CPT1A/malonyl-CoA partnership, can reverse an already established hepatic steatosis and IR in obese mice. Methods: Adenovirus-mediated liver expression of a malonyl-CoA-insensitive CPT1A (CPT1mt) in high-fat/high-sucrose (HF/HS) diet-induced or genetically (ob/ob) obese mice was followed by metabolic and physiological investigations. Results: In association with increased hepatic mFAO capacity, liver CPT1mt expression improved glucose tolerance and insulin response to a glucose load in HF/HS and ob/ob mice, showing increased insulin sensitivity, and corrected IR in ob/ob mice. Surprisingly, hepatic steatosis was not affected in CPT1mt-expressing obese mice, indicating a clear dissociation between hepatic steatosis and IR. Moreover, liver CPT1mt expression rescued HF/HS-induced impaired hepatic insulin signaling at the level of IRS-1, IRS-2, Akt, and GSK-3β, most likely through the observed decrease in the HF/HS-induced accumulation of lipotoxic lipids, oxidative stress, and JNK activation. Conclusions: Enhancing hepatic mFAO capacity is sufficient to reverse a state of IR and glucose intolerance in obese mice independently of hepatic steatosis. [Copyright &y& Elsevier]

Effective treatment options for patients with metastatic breast cancer (MBC) resistant/refractory to anthracyclines and/or taxanes are limited. Intravenous and oral combination of vinorelbine (VRL) and capecitabine were shown to be feasible and effective in first-line MBC. In order to evaluate the activity of the combination of an all oral regimen in a more advanced setting, we investigated a regimen combining oral VRL and capecitabine in a phase II study as second-line chemotherapy of MBC patients previously treated with anthracyclines and taxanes. Forty patients (median age 52 years) with MBC received the combination of oral VRL 60 mg/m² on days 1, 8 and 15 plus capecitabine 1,000 mg/m² bid given from day 1 to day 14 in an open-label, international, multicentre, phase II study. Cycles were repeated every 3 weeks. The primary endpoint was response rate (RR) evaluated by an independent panel review. Secondary objectives included safety, duration of response, progression-free survival, overall survival and quality of life. All the patients had received prior chemotherapy with anthracyclines and taxanes, 75% were refractory/resistant to anthracycline and/or taxane, 72.5% presented with visceral involvement and the last prior chemotherapy for 87.5% of the patients was for advanced disease setting. The median number of administered cycles per patient was 4 (range 1–31). Eight responses were documented and validated by an independent panel review, yielding RRs of 20% [95% CI: 9–35.6] in the intent-to-treat (treated) population and 23.5% [95% CI: 10.7–41.2] in the 34 evaluable patients. Median progression-free survival and median overall survival were 3.4 months [95% CI: 2.3–5.5] and 11.3 months [95% CI: 8.1–16.4], respectively. The principal toxicities were anaemia, neutropenia (rarely complicated; only one patient experienced febrile neutropenia), fatigue and gastrointestinal toxicities with very few grade 3–4 non-haematological toxicities. In second-line treatment of MBC patients previously treated with anthracyclines and taxanes, oral VRL plus capecitabine is a safe regimen with an efficacy comparable to the other available combination regimens used in this heavily and resistant/refractory (75% of patients) pre-treated patients’ population. Moreover, this well-tolerated combination offers the advantages of an all oral regimen. [ABSTRACT FROM AUTHOR]

Background and Objectives: More and more anticancer chemotherapies are now available as oral formulations. This relatively new route of administration in oncology leads to problems with patient education and non-compliance. The aim of this study was to explore the performances of the 'inverse problem', namely, estimation of compliance from pharmacokinetics. For this purpose, we developed and evaluated a method to estimate patient compliance with an oral chemotherapy in silico (i) from an a priori population pharmacokinetic model; (ii) with limited optimal pharmacokinetic information collected on day 1; and (iii) from a single pharmacokinetic sample collected after multiple doses.Methods: Population pharmacokinetic models, including estimation of all fixed and random effects estimated on a prior dataset, and sparse samples taken after the first dose, were combined to provide the individual POSTHOC Bayesian pharmacokinetic parameter estimates. Sampling times on day 1 were chosen according to a D-optimal design. Individual pharmacokinetic profiles were simulated according to various dose-taking scenarios. To characterize compliance over the n previous dosing times (supposedly known without error), 2n different compliance scenarios of doses taken/not taken were considered. The observed concentration value was compared with concentrations predicted from the model and each compliance scenario. To discriminate between different compliance profiles, we used the Euclidean distance between the observed pharmacokinetic values and the predicted values simulated without residual errors. This approach was evaluated in silico and applied to imatinib and capecitabine, the pharmacokinetics of which are described in the literature, and which have quite different pharmacokinetic characteristics (imatinib has an elimination half-life of 17 hours, and alpha-fluoro-beta-alanine [FBAL], the metabolite of capecitabine, has an elimination half-life of 3 hours). 1000 parameter sets were drawn according to population distributions, and concentration values were simulated at several timepoints under various compliance patterns to compare with the predicted ones. In addition, several simulation scenarios were run in order to explore the impact of the quality of the error model, interoccasion variability (IOV), error in the number of pills taken, and the performance of the compliance estimation method.Results: The best compliance estimate was obtained with pharmacokinetic samples taken 5 hours after the last dose. Performance of the method varied between simulation scenarios. In both the imatinib and capecitabine basic simulations, patient compliance was correctly estimated on the two last scheduled doses (with better results for imatinib). The magnitude of the error model also had a great impact on the quality of the compliance estimate.Conclusions: We highlight the effect of three parameters on the quality of compliance estimates based on limited pharmacokinetic information: the plasma elimination half-life, interdose interval and magnitude of the error model. Nevertheless, the pharmacokinetic method is not informative enough and should be used with electronic monitoring, which provides additional information on compliance. Our method will be used in a future phase IV clinical trial where the relationships between compliance, efficacy and tolerability will be assessed. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Twin pregnancy with complete hydatidiform mole and coexistent fetus (CHM&CF) is a rare situation and a challenge for diagnosis. Results related to fetal outcome and maternal risk of subsequent gestational trophoblastic neoplasia (GTN) are controversial. We here display a series from the French Trophoblastic Disease Reference Center, which is to date the third in number of cases registered by the same center. Study design: By retrospective method based on patients from the French Trophoblastic Disease Reference Center data base between November 1999 and December 2006, 17 assumed cases were reviewed. In 14 cases the diagnosis of CHM&CF was ascertained. All files were reviewed to confirm diagnosis. Methods of initial diagnosis, outcome of pregnancy and evolution to GTN were studied. Results: In 10 cases (71%) diagnosis was made by ultrasonography. Differential diagnoses were partial hydatidiform mole and mesenchymal dysplasia. Three patients in 14 (21%) delivered a healthy child. In only one case, delivery occurred after 37 weeks of gestation. Seven patients (50%) had a diagnosis of GTN. No patient had fatal evolution. Clinical events, such as vaginal bleeding, pre-eclampsia or hyperthyroidism, had no effect on the evolution to GTN. Continuation of the pregnancy did not increase the risk of GTN. Conclusion: In case of prenatal diagnosis of CHM&CF, and even if delivery of a healthy child is possible, patients should be aware of a possibly higher risk of GTN than in CHM. [Copyright &y& Elsevier]

Summary: Purpose: To investigate the prognostic value of systemic exposure to etoposide (Area Under the concentration Curve (AUCVP16)) on overall survival (OS) in patients with small cell lung cancer (SCLC). Patients and methods: Data from 52 patients with limited stage (n =17) or metastatic (n =35) SCLC were analysed. They received at least two courses of etoposide (120mg/(m2 day) on 3 days) combined with either doxorubicin–ifosfamide (AVI, n =29) or platinum compounds (carboplatin: n =16; cisplatin: n =7). Population pharmacokinetic–pharmacodynamic (PK–PD) study was performed using NON-linear Mixed Effect Model (NONMEM) and Splus software with univariate and multivariate analyses. Results: Etoposide plasma concentration vs. time was described by a two compartment model. Etoposide clearance (CL) was significantly dependant on serum creatinine (Scr). Ifosfamide (IFO) coadministration increased etoposide clearance by 28% (median CLVP16: 2.42L/h vs. 1.89L/h, p <0.0005) leading to a reduced systemic exposure (median AUCVP16: 260mgh/L vs. 339mgh/L). No influence of body surface area (BSA) on CLVP16 was observed. Median percent decrease of absolute neutrophil count (ANC) after the first chemotherapy course was greater when etoposide 24h concentration was above 0.33mg/L (88% vs. 0%, p =0.028). Median OS was significantly longer in patients treated without ifosfamide (11.0 months vs. 7.0 months, p =0.049) and in patients with CLVP16 <2.22L/h (14 months vs. 7 months, p =0.013) and AUCVP16 >254.8mgh/L (11 months vs. 7 months, p =0.048). The independent prognostic factors regarding OS were LDH, CLVP16 and AUCVP16. Conclusion: In this study it was found that CLVP16 is reduced in patients with elevated serum creatinine, whilst ifosfamide coadministration increases CLVP16 and reduces AUCVP16, demonstrating the interaction between VP16 and ifosfamide. CLVP16 and AUCVP16 correlate significantly with overall survival of patients with SCLC patients receiving etoposide regimens. [Copyright &y& Elsevier]

Abstract: Objective. : Gestational trophoblastic diseases (GTD), a group of rare placenta disorders, have a varying potential for invasion, either local, or remote under the form of metastases, and are definitely cured by chemotherapy in 85 to 99% of cases. Single-agent methotrexate is the usual primary treatment for women with low-risk trophoblastic tumors (TT), yet various regimens are currently used worldwide. We reviewed these regimens and the available evidence for evaluating their respective efficacy and tolerance. Methods. : We performed an exhaustive literature search and applied the French agency for evaluation in healthcare (HAS) methodology for critical appraisal and level of evidence. We summarised the protocols used in the selected studies and their respective results regarding efficacy and toxicity. Results. : We selected 18 original studies on the efficacy and tolerance of methotrexate used alone or in association with folinic acid for the treatment of nonmetastatic or low-risk metastatic trophoblastic tumors. Among these 18 studies, 15 were retrospective series, 3 were prospective series without any control group, and none were controlled clinical trial. We identified four main chemotherapy regimens and two very different strategies for repeating the treatment courses. It was not possible to perform a metaanalysis due to the lack of controlled clinical trials. Because all studies were observational with no control group and methods were heterogeneous for scoring women, setting criteria for starting therapy, defining remission, and collecting information on adverse events, we found no objective element allowing recommending one protocol rather than another. Conclusion. : Objective comparison should be addressed in the scope of comparative trials organised at the national or even international level. However their feasibility is highly problematic for rare diseases such as GTD. International collaborative works should be encouraged to reduce practice variations and allow a better comparability between strategies. [Copyright &y& Elsevier]

Aims To determine the population pharmacokinetic (PK) parameters of doxorubicin (Dox), etoposide (Eto) and ifosfamide (Ifo) in small cell lung cancer (SCLC) patients, to assess the potential relationship between those parameters and to estimate the impact of individual morphological and biological covariates on patients' PK parameters. Methods Twenty-four patients with either SCLC limited to the thorax or extensive SCLC entered the study. All but one received at least two 3 day courses of the standard AVI (Dox 50 mg m-2 day 1, Eto 120 mg m-2 day 1,2,3, Ifo 2000 mg m-2 day 1,2) regimen. Individual blood samples were collected during each course and data on 47 courses were available. Data were analysed with the NONMEM program. Dox, Eto and Ifo plasma concentrations were studied with multicompartment (3, 2 and 2, respectively) models. Inter-individual and interoccasion (course-to-course) variabilities were estimated. The influence of individual covariates (age, sex, stage of the disease, weight, height, body-surface area, serum creatinine, total protein, LDH, ASAT, ALAT, alkaline phosphatase, gamma-GT, bilirubin) on PK parameters was also assessed. Correlations between individual PK parameters of Dox, Eto and Ifo were explored by using Pearson's correlation coefficient. Results Multiple data were available for each patient. Dox clearance (CL) and volume of distribution (Vd) were 32.0 l h-1 and 9.3 l (Inter-individual variability: 17.2% and 19.2%). Eto CL (l h-1) and Vd were, respectively, 3.34–0.0083* serum creatinine (µmol l-1) and 6.38 l (interindividual variability: 15.6% and 18.7%). Ifo CL and Vd at day 1 were 5.6 l h-1 and 26.0 l (interindividual variability: 10.1% and 17.2%, respectively). Estimation of course-to-course variability improved the precision of PK models in some cases. No correlation was observed between the respective PK parameters of each drug. Of individual covariates tested, only serum creatinine correlated with Eto CL (r = -0.37, P < 0.001). Self-induction of the metabolism of Ifo was apparent (mean CL increase from day 1 to day 2 : 42%) and individually correlated with the CL value at day 1 (r = -0.61, P < 0.001). Conclusions Assessment of potential relationships between individual systemic exposure of chemotherapy and therapeutic endpoints (tumour response, toxicity and survival) will be required to adjust drugs dosages based on individual PK parameters rather than questionable body-surface area. However, all three drugs in the AVI regimen should be monitored simultaneously. [ABSTRACT FROM AUTHOR]

In the liver, contact sites between the endoplasmic reticulum (ER) and mitochondria (named MAMs) may be crucial hubs for the regulation of lipid metabolism, thus contributing to the exacerbation or prevention of fatty liver. We hypothesized that tether proteins located at MAMs could play a key role in preventing triglyceride accumulation in hepatocytes and nonalcoholic fatty liver disease (NAFLD) occurrence. To test this, we explored the role of two key partners in building MAM integrity and functionality, the glucose-regulated protein 75 (Grp75) and mitofusin 2 (Mfn2), which liver contents are altered in obesity and NAFLD. Grp75 or Mfn2 expression was either silenced using siRNA or overexpressed with adenoviruses in Huh7 cells. Silencing of Grp75 and Mfn2 resulted in decreased ER-mitochondria interactions, mitochondrial network fusion state and mitochondrial oxidative capacity, while overexpression of the two proteins induced mirror impacts on these parameters. Furthermore, Grp75 or Mfn2 silencing decreased cellular cholesterol content and enhanced triglyceride secretion in ApoB100 lipoproteins, while their overexpression led to reverse effects. Cellular phosphatidylcholine/phosphatidylethanolamine ratio was decreased only upon overexpression of the proteins, potentially contributing to altered ApoB100 assembly and secretion. Despite the opposite differences, both silencing and overexpression of Grp75 or Mfn2 induced triglyceride storage, although a fatty acid challenge was required to express the alteration upon protein silencing. Among the mechanisms potentially involved in this phenotype, ER stress was closely associated with altered triglyceride metabolism after Grp75 or Mfn2 overexpression, while blunted mitochondrial FA oxidation capacity may be the main defect causing triglyceride accumulation upon Grp75 or Mfn2 silencing. Further studies are required to decipher the link between modulation of Grp75 or Mfn2 expression, change in MAM integrity and alteration of cholesterol content of the cell. In conclusion, Grp75 or Mfn2 silencing and overexpression in Huh7 cells contribute to altering MAM integrity and cholesterol storage in opposite directions, but all promote triglyceride accumulation through distinct cellular pathways. This study also highlights that besides Mfn2, Grp75 could play a central role in hepatic lipid and cholesterol metabolism in obesity and NAFLD. [Display omitted] • Loss or gain of function of Grp75 or Mfn2 have mirror impacts on markers of MAM integrity in hepatocytes. • They also have an inverse impact on the cholesterol content of cells. • All conditions induce triglyceride storage, albeit by distinct mechanisms. • Identified mechanisms involve blunted mitochondrial fatty acid oxidative capacity upon Grp75 or Mfn2 silencing, • and ER stress and ApoB100 lipoprotein assembly upon Grp75 or Mfn2 overexpression. [ABSTRACT FROM AUTHOR]