Tumor Homogeneity between Primary and Metastatic Sites for BRAF Status in Metastatic Melanoma Determined by Immunohistochemical and Molecular Testing

BRAF inhibitors have demonstrated improvement of overall survival in patients with metastatic melanoma and BRAF^V600 mutations. In order to evaluate BRAF tumor heterogeneity between primary and metastatic site, we have evaluated the performance of immunohistochemistry (IHC) with an anti-BRAF^V600E antibody in both localization by comparison with high resolution melting analysis followed by Sanger sequencing in a parallel blinded study. A total of 230 samples distributed as primary melanoma (n = 88) and different types of metastatic samples (n = 142) were studied in 99 patients with advanced or metastatic melanoma (stage III or IV). The prevalence of each BRAF mutation was c.1799T>A, BRAF^V600E (45.2%), c.1799_1800TG>AA, BRAF^V600E2 (3.0%), c.1798_1799GT>AA, BRAF^V600K (3.0%), c.1801 A>G, BRAF^K601E (1.3%), c.1789_1790CT>TC, BRAF^L597S (0.4%), c.1780G>A, BRAF^D594N (0.9%) respectively. IHC was positive in 109/112 samples harboring BRAF^V600E/E2 mutations and negative in other cases. The cytoplasmic staining was either strongly positive in tumor cells of BRAF^V600E mutated cases. It appeared strong brown, different from the vesicular grey cytoplasmic pigmentation of melanophages. Concordance between the two techniques was 96.4%. Sensitivity of IHC for detecting the BRAF^V600E/E2 mutations was 97.3%, while specificity was 100%. Both our IHC and molecular study demonstrated homogeneity between primary and metastatic sites for BRAF status in melanoma. This study also provides evidence that IHC may be a cost-effective first-line method for BRAF^V600E detection. Thereafter, molecular techniques should be used in negative, ambiguous or non-contributive cases.     

L’Homme fossile d’Asselar (actuel Mali). Étude critique,mise en perspective historique et nouvelles interprétations

During the well known Augiéras-Draper mission which took place in 1927 and 1928 between Dakar and Alger through the Sahara desert, T. Monod and V. Besnard discovered a human skeleton near the military post of Asselar in French Sudan (current Mali). Back in France, the fossil was given to the Institut de Paléontologie Humaine where M. Boule and H. Vallois were in charge of its study. This work was then published in 1932. After this first exhaustive study, Asselar man was barely used in anthropological studies, with the exception of O. Dutour's works in the 90's. The goal of this study is to understand why, despite some prestige, this fossil didn’t have the importance he was fated with its geographical and chronological position. Publications of the first third of the twentieth century, archives about this discovery and the skeleton it-self are in the center of this new analysis. Results show that because of the lack of specification about its unearthing and its dating, Asselar fossil is hardly usable in an anthropological perspective. It although shows that Boule et Vallois limited the study of this fossil to a discussion about the Grimaldi “race”, designation not use anymore. This race was created in 1906 by R. Verneau and the discussion of the relation between Asselar man and Grimaldi race was a virulent debate at this time. Finally, the study of Asselar skeleton with archeo-anthropological principles gave the opportunity to demonstrate, for the first time, a sepulchral context. This rehabilitation of Asselar fossil gives new perspectives which would be investigate with new approaches in dating, genetics, 3D imaging… and will fully contribute to discussions about North Africa peopling.     

A new N-methyl thymine derivative comprising a dihydroxyisobutenyl unit as ligand for thymidine kinase of herpes simplex virus type 1 (HSV-1 TK)

Molecular modeling and phosphorylation assay in vitro were employed to select a novel unsaturated 1,3-dihydroxyisobutenyl thymine derivative 6 as ligand for HSV-1 TK which may be of interest as lead for the development of an positron emission tomography (PET) imaging agent. Compound 6 was successfully prepared using modified approaches. A significant improvement over the syntheses involving pathways A and B (1% and 3% overall yield, respectively), was observed using synthetic route C (14% overall yield).     

Cloning, expression, and characterization of Mycobacterium tuberculosis dihydrofolate reductase

The gene for dihydrofolate reductase of Mycobacterium tuberculosis was amplified by polymerase chain reaction (PCR) from M. tuberculosis H37Rv strain genomic DNA. The protein was expressed in inclusion bodies in high yield in Escherichia coli under the control of the T7 promoter. Active enzyme was obtained by refolding from guanidine HCl and after a single chromatography step the sample was > 99% homogeneous with a specific activity of approximately 15.5 micromol min(-1) mg(-1). Mass spectrometry analysis confirmed the expected mass of 17.6 kDa. Gel filtration of the enzyme indicated that it was a monomer. Steady-state kinetic parameters were determined and the effect of pH and KCl on the enzyme examined. Methotrexate and trimethoprim inhibited the enzyme.     

Discovery of novel benzoquinazolinones and thiazoloimidazoles, inhibitors of influenza H5N1 and H1N1 viruses, from a cell-based high-throughput screen

A highly reproducible and robust cell-based high-throughput screening (HTS) assay was adapted for screening of small molecules for antiviral activity against influenza virus strain A/Vietnam/1203/2004 (H5N1). The NIH Molecular Libraries Small Molecule Repository (MLSMR) Molecular Libraries Screening Centers Network (MLSCN) 100,000-compound library was screened at 50 μM. The "hit" rate (>25% inhibition of the viral cytopathic effect) from the single-dose screen was 0.32%. The hits were evaluated for their antiviral activity, cell toxicity, and selectivity in dose-response experiments. The screen yielded 5 active compounds (SI value >3). One compound showed an SI(50) value of greater than 3, 3 compounds had SI values ranging from greater than 14 to 34, and the most active compound displayed an SI value of 94. The active compounds represent 2 different classes of molecules, benzoquinazolinones and thiazoloimidazoles, which have not been previously identified as having antiviral/anti-influenza activity. These molecules were also effective against influenza A/California/04/2009 virus (H1N1) and other H1N1 and H5N1 virus strains in vitro but not H3N2 strains. Real-time qRT-PCR results reveal that these chemotypes significantly reduced M1 RNA levels as compared to the no-drug influenza-infected Madin Darby canine kidney cells.     

Anthropometric factors, physical activity, and risk of non-Hodgkin's lymphoma in the Women's Health Initiative

Background: Incidence rates of non-Hodgkin's lymphoma (NHL) increased substantially in the United States and worldwide during the latter part of the 20th century, but little is known about its etiology. Obesity is associated with impaired immune function through which it may influence the risk of NHL; other factors reflecting energy homeostasis (height, abdominal adiposity, and physical activity) may also be involved. Methods: We examined the association of anthropometric factors and physical activity with risk of NHL and its major subtypes in a large cohort of women aged 50–79 years old who were enrolled at 40 clinical centers in the United States between 1993 and 1998. Over a mean follow-up period of 11 years, 1123 cases of NHL were identified among 158,975 women. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI). Results: Height at baseline was positively associated with risk of all NHL and with that of diffuse large B-cell lymphoma (HRs_q4vs.q1 1.19, 95% CI 1.00–1.43 and 1.43, 95% CI 1.01–2.03, respectively). Measures of obesity and abdominal adiposity at baseline were not associated with risk. Hazard ratios for NHL were increased for women in the highest quartile of weight and body mass index at age 18 (HRs_q4vs.q1 1.29, 95% CI 1.01–1.65 and 1.27, 95% CI 1.01–1.59, respectively). Some measures of recreational physical activity were modestly associated with increased risk of NHL overall, but there were no clear associations with specific subtypes. Conclusion: Our findings regarding anthropometric measures are consistent with those of several previous reports, suggesting that early life influences on growth and immune function may influence the risk of NHL later in life.