Safety and Immunogenicity of the PRAME Cancer Immunotherapeutic in Patients with Resected Non–Small Cell Lung Cancer: A Phase I Dose Escalation Study

International audience; INTRODUCTION:Adjuvant platinum-based chemotherapy is standard treatment for surgically resected stage II to IIIA NSCLC, but the relapse rate is high. The preferentially expressed antigen of melanoma (PRAME) tumor antigen is expressed in two-thirds of NSCLC and offers an attractive target for antigen-specific immunization. A phase I dose escalation study assessed the safety and immunogenicity of a PRAME immunotherapeutic consisting of recombinant PRAME plus proprietary immunostimulant AS15 in patients with surgically resected NSCLC (NCT01159964).METHODS:Patients with PRAME-positive resected stage IB to IIIA NSCLC were enrolled in three consecutive cohorts to receive up to 13 injections of PRAME immunotherapeutic (recombinant PRAME protein dose of 20 μg, 100 μg, or 500 μg, with a fixed dose of AS15). Adverse events, predefined dose-limiting toxicity, and the anti-PRAME humoral response (measured by enzyme-linked immunosorbent assay) were coprimary end points. Anti-PRAME cellular responses were assessed.RESULTS:A total of 60 patients were treated (18 received 20 μg of PRAME, 18 received 100 μg of PRAME, and 24 received 500 μg of PRAME). No dose-limiting toxicity was reported. Adverse events considered by the investigator to be causally related to treatment were grade 1 or 2, and most were injection site reactions or fever. All patients had detectable anti-PRAME antibodies after four immunizations. The percentages of patients with PRAME-specific CD4-positive T cells were higher at the dose of 500 μg compared with lower doses. No predefined CD8-positive T-cell responses were detected.CONCLUSION:The PRAME immunotherapeutic had an acceptable safety profile. All patients had anti-PRAME humoral responses that were not dose related, and 80% of those treated at the highest dose showed a cellular immune response. The dose of 500 μg was selected. However, further development was stopped after negative results with a similar immunotherapeutic in patients with NSCLC

Safety and Immunogenicity of MAGE-A3 Cancer Immunotherapeutic with or without Adjuvant Chemotherapy in Patients with Resected Stage IB to III MAGE-A3-Positive Non-Small-Cell Lung Cancer

Introduction: To assess the safety and immunogenicity of MAGE-A3 immunotherapeutic in patients with stage IB-III MAGE-A3-positive non-small-cell lung cancer (NSCLC) who were or were not undergoing standard cisplatin/vinorelbine chemotherapy. Methods: This open, prospective, multicenter, parallel-group phase I study (NCT00455572) enrolled patients with resected (cohorts 1-3) or unresectable (cohort 4) MAGE-A3-positive NSCLC. MAGE-A3 immunotherapeutic (300 g recombinant MAGE-A3 formulated with AS15) was administered (eight doses, 3 weeks apart) concurrent with (cohort 1), after (cohort 2), or without (cohort 3) standard-adjuvant chemotherapy, or after standard radiotherapy and/or chemotherapy (cohort 4). Results: Sixty-seven patients received greater than or equal to 1 dose of MAGE-A3 immunotherapeutic. Grade 3/4 adverse events (AEs) were reported for 16 out of 19 (84%), 2 out of 18 (11%), 5 out of 18 (28%), and 1 out of 12 (8%) patients in cohorts 1, 2, 3, and 4, respectively. Many grade 3/4 AEs in cohort 1 (e.g., neutropenia) were typical of chemotherapy. Six patients, including three in cohort 1, reported study treatment-related grade 3/4 AEs (injection-site reactions or musculoskeletal/back pain, which resolved within 5 days). One patient (in cohort 4) died, but this and the other serious adverse events were not study treatment related. MAGE-A3-specific antibody responses to immunotherapy were induced in all patients evaluated in all cohorts. MAGE-A3-specific CD4(+) T-cell responses to immunotherapy were detected in 4 out of 11 (36%), 4 out of 15 (27%), 2 out of 8 (25%), and 5 out of 6 (83%) evaluated patients in cohorts 1, 2, 3, and 4, respectively; and CD8(+) T-cell responses were only detected in four patients. Conclusion: In resected and unresectable NSCLC patients and irrespective of whether standard chemotherapy was concurrent or not, MAGE-A3 immunotherapeutic is well tolerated and induces MAGE-A3-specific immune responses. GlaxoSmithKline Biologicals SA sponsored the clinical trial and covered the costs associated with the development and publishing of the manuscript, including scientific writing assistance. adjuvant chemotherapy; immunotherapy; immunostimulant; MAGE-A3; non–small cell lung carcinoma; vaccin

The Evolution of Primate Short-Term Memory.

Short-term memory is implicated in a range of cognitive abilities and is critical for understanding primate cognitive evolution. To investigate the effects of phylogeny, ecology and sociality on short-term memory, we tested the largest and most diverse primate sample to date (421 non-human primates across 41 species) in an experimental delayed-response task. Our results confirm previous findings that longer delays decrease memory performance across species and taxa. Our analyses demonstrate a considerable contribution of phylogeny over ecological and social factors on the distribution of short-term memory performance in primates; closely related species had more similar short-term memory abilities. Overall, individuals in the branch of Hominoidea performed better compared to Cercopithecoidea, who in turn performed above Platyrrhini and Strepsirrhini. Interdependencies between phylogeny and socioecology of a given species presented an obstacle to disentangling the effects of each of these factors on the evolution of short-term memory capacity. However, this study offers an important step forward in understanding the interspecies and individual variation in short-term memory ability by providing the first phylogenetic reconstruction of this trait’s evolutionary history. The dataset constitutes a unique resource for studying the evolution of primate cognition and the role of short-term memory in other cognitive abilities.info:eu-repo/semantics/publishedVersio

The Evolution of Primate Short-Term Memory

Short-term memory is implicated in a range of cognitive abilities and is critical for understanding primate cognitive evolution. To investigate the effects of phylogeny, ecology and sociality on short-term memory, we tested the largest and most diverse primate sample to date (421 non-human primates across 41 species) in an experimental delayed-response task. Our results confirm previous findings that longer delays decrease memory performance across species and taxa. Our analyses demonstrate a considerable contribution of phylogeny over ecological and social factors on the distribution of short-term memory performance in primates; closely related species had more similar short-term memory abilities. Overall, individuals in the branch of Hominoidea performed better compared to Cercopithecoidea, who in turn performed above Platyrrhini and Strepsirrhini. Interdependencies between phylogeny and socioecology of a given species presented an obstacle to disentangling the effects of each of these factors on the evolution of short-term memory capacity. However, this study offers an important step forward in understanding the interspecies and individual variation in short-term memory ability by providing the first phylogenetic reconstruction of this trait’s evolutionary history. The dataset constitutes a unique resource for studying the evolution of primate cognition and the role of short-term memory in other cognitive abilities

Antigens recognized on human melanoma by cytolytic T lymphocytes

Des expériences réalisées sur des modèles murins ont montré que des antigènes reconnus sur des tumeurs par des lymphocytes T cytolytiques (CTL) sont la cible d’une réponse immunitaire qui détruit les cellules tumorales sans endommager les tissus sains. Au cours de ces dernières années, plusieurs gènes codant des antigènes présents sur des mélanomes humains et reconnus par des CTL autologues ont été identifiés. Le premier gène, appelé MAGE-1, appartient à une famille d’au moins douze membres. Ces gènes sont activés dans différents types de tumeurs. Ils ne sont pas exprimés dans les tissus normaux, à l’exception du testicule et, pour certains, du placenta. D’autres antigènes tumoraux sont crées par des mutations ponctuelles affectant les cellules tumorales. Enfin, les CTL de certains patients atteints de mélanome reconnaissent des antigènes de différenciation de la lignée mélanocytaire, présents sur les mélanomes mais aussi sur les mélanocytes normaux. Grâce à la connaissance précise des antigènes tumoraux, il sera possible, à partir d’un prélèvement tumoral, d’identifier les patients dont la tumeur exprime un ou plusieurs antigènes. Ces patients pourraient dès lors recevoir un traitement d’immunothérapie spécifiquement dirigé contre les antigènes présents sur leur tumeurThèse d'agrégation de l'enseignement supérieur (faculté de médecine) -- UCL, 199

Diet- and diabetes-induced changes of ob gene expression in rat adipose tissue.

ob gene regulation is as yet unknown. We first examined whether the ob gene is under physiological control by the nutritional state. Fasting produced a sharp (95%) decrease of ob mRNA in epididymal and inguinal fat pads from 24 h onward. Refeeding rapidly (3-6 h) re-induced ob gene expression and corrected it within 24 h. Similar changes in fatty acid synthase (FAS) and GLUT4 mRNAs were observed, whereas phosphoenolpyruvate carboxykinase (PEPCK) mRNA showed an opposite evolution. We next examined the potential role of insulin. In adipose tissue of streptozotocin-diabetic rats, ob mRNA levels were decreased by 80%. Insulin treatment (4 days) only marginally increased ob mRNA, but restored euglycemia and overcorrected FAS, GLUT4 and PEPCK expression. In conclusion, we provide evidence for a physiological regulation of ob gene by variations in the nutritional state. We also show that ob expression is impaired in streptozotocin-diabetic rats and only slightly restored by insulin treatment, which suggests that ob gene is not or only minimally regulated by the hormone

Hypoleptinemia in patients with anorexia nervosa: loss of circadian rhythm and unresponsiveness to short-term refeeding.

Leptin is a protein encoded by the ob gene that is expressed in adipocytes and regulates eating behavior via neuroendocrine mechanisms. Plasma leptin levels have been shown to correlate with weight and body fat in normal, obese and anorexic subjects. In the last of these populations, the dynamic profile of plasma leptin levels during short-term refeeding has never been assessed. We thus investigated basal plasma leptin levels in 29 female patients with anorexia nervosa (AN) (age 21.9 +/- 1.4 years, body mass index (BMI) 15.2 +/- 0.3 kg/m2) and in 80 normal female controls (age 21.2 +/- 0.2 years, BMI 20.3 +/- 0.3 kg/m2, mean +/- S.E.M.). Basal plasma leptin levels in AN were decreased by 77% compared with controls (2.5 +/- 0.2 vs 11.1 +/- 0.7 ng/ml, P < 0.0001). In both AN subjects and controls, plasma leptin levels correlated significantly with BMI (r2 = 0.448, P < 0.0001 and r2 = 0.339, P < 0.0001 respectively). Five AN patients (four female, one male, age 22.0 +/- 4.7 years, BMI 14.2 +/- 0.4 kg/m2, body fat 4.3 +/- 0.9 kg or 11.0 +/- 1.9% of body weight, basal metabolic rate (BMR) 958 +/- 122 kcal/day) were studied during a 3-day refeeding period and compared with eight control subjects (two male, six female, age 25.7 +/- 1.2 years, BMI 21.3 +/- 0.8 kg/m2, body fat 15.1 +/- 0.9 kg or 24.6 +/- 1.7%, BMR 1455 +/- 78 kcal/day) submitted to 36-h fasting. The amount of calories administered was based on BMR + 20% (carbohydrate 60%, protein 17%, fat 23%). In contrast to the rise in leptin levels that occurred during refeeding after a prolonged fast period in normal subjects, plasma leptin levels remained low and unchanged throughout the 3 days of renutrition in AN patients. The circadian rhythm of leptin was also completely abolished. This contrasted with the preserved circadian variations of cortisol, whose mean levels were increased. In conclusion, we confirmed that plasma leptin levels are low in AN and correlate with body weight. We further demonstrated that plasma leptin levels do not respond to short-term refeeding in anorexic patients in whom circadian variations are not restored, which suggests that the acute regulation of leptin by positive changes in energy balance is not preserved under a critical threshold of body fat

New tumor-antigens recognized by T-cells

A series of tumor cell antigens that are recognized by cytolytic T lymphocytes has been characterized this year. Besides the antigens derived from proteins specifically expressed in tumors, many melanoma antigens derive from melanocytic differentiation proteins. In addition, antigens unique to individual tumors result from mutations in ubiquitously expressed genes

Tumor rejection antigens and specific immunotherapy of cancer

Experiments with mouse systems have shown that antigens recognized on tumors by cytolytic T lymphocytes can be the targets of immune responses that destroy the tumor cells without exerting harmful effects on normal tissues. in recent years, a number of genes that code for these antigens have been identified. The first gene studied, MAGE-1, coded for an antigen recognized by an autologous cytolytic T-cell clone. It belongs to a family comprising at least twelve members, but the function of the proteins encoded remains unknown. these genes have no expression in normal tissues (but testis and placenta); the tumoral peptides are presented to the immune system by specific HLA molecules. some other tumoral antigens are not restricted to tumors but appear on normal melanocytes (tryrosinase, gp100...). Knowing these genes opens new possibilities in specific cancer immunotherapy