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Ferredoxins (Fed), occurring in most organisms, are small proteins that use their iron-sulfur cluster to distribute electrons to various metabolic pathways, likely including hydrogen production. Here, we summarize the current knowledge on ferredoxins in cyanobacteria, the prokaryotes regarded as important producers of the oxygenic atmosphere and biomass for the food chain, as well as promising cell factories for biofuel production. Most studies of ferredoxins were performed in the model strain, Synechocystis PCC6803, which possesses nine highly-conserved ferredoxins encoded by monocistronic or operonic genes, some of which are localized in conserved genome regions. Fed1, encoded by a light-inducible gene, is a highly abundant protein essential to photosynthesis. Fed2-Fed9, encoded by genes differently regulated by trophic conditions, are low-abundant proteins that play prominent roles in the tolerance to environmental stresses. Concerning the selectivity/redundancy of ferredoxin, we report that Fed1, Fed7 and Fed9 belong to ferredoxin-glutaredoxin-thioredoxin crosstalk pathways operating in the protection against oxidative and metal stresses. Furthermore, Fed7 specifically interacts with a DnaJ-like protein, an interaction that has been conserved in photosynthetic eukaryotes in the form of a composite protein comprising DnaJ- and Fed7-like domains. Fed9 specifically interacts with the Flv3 flavodiiron protein acting in the photoreduction of O2 to H2O.

Abstract The secreted factor netrin‐1 is upregulated in a fraction of human cancers as a mechanism to block apoptosis induced by netrin‐1 dependence receptors DCC and UNC5H. Targeted therapies aiming to trigger tumour cell death via netrin‐1/receptors interaction interference are under preclinical evaluation. We show here that Doxorubicin, 5‐Fluorouracil, Paclitaxel and Cisplatin treatments trigger, in various human cancer cell lines, an increase of netrin‐1 expression which is accompanied by netrin‐1 receptors increase. This netrin‐1 upregulation which appears to be p53‐dependent is a survival mechanism as netrin‐1 silencing by siRNA is associated with a potentiation of cancer cell death upon Doxorubicin treatment. We show that candidate drugs interfering with netrin‐1/netrin‐1 receptors interactions potentiate Doxorubicin, Cisplatin or 5‐Fluorouracil‐induced cancer cell death in vitro. Moreover, in a model of xenografted nude mice, we show that systemic Doxorubicin treatment triggers netrin‐1 upregulation in the tumour but not in normal organs, enhancing and prolonging tumour growth inhibiting effect of a netrin‐1 interfering drug. Together these data suggest that combining conventional chemotherapies with netrin‐1 interference could be a promising therapeutic approach.

Pierre Heudel,1 Philippe Cassier,1 Olfa Derbel,1 Armelle Dufresne,1 Pierre Meeus,2 Philippe Thiesse,3 Dominique Ranchère-Vince,4 Jean Yves Blay,1 Isabelle Ray-Coquard1,51Department of Medical Oncology, 2Department of Surgical Oncology, 3Department of Radiology, 4Department of Pathology, Leon Berard Center, Lyon, 5EAM 4128 Sante-Individu-Societe, Lyon University, Lyon, FranceAbstract: Pazopanib is a multikinase inhibitor which potently inhibits the activity of major receptor tyrosine kinases, including vascular endothelial growth factor receptor-1, vascular endothelial growth factor receptor-2, vascular endothelial growth factor receptor-3, platelet-derived growth factor receptor-a, platelet-derived growth factor receptor-a, and c-Kit. Approved by the Food and Drug Administration in 2009 in the United States for the treatment of metastatic renal cell carcinoma, pazopanib has been tested in advanced or metastatic soft-tissue sarcoma. Unlike other tyrosine kinase inhibitors, a statistically significant efficacy in phase II but also in randomized phase III studies has been shown. In comparison with sunitinib or sorafenib, pazopanib has a similar toxicity profile and is generally well tolerated. This review details the development of this new therapeutic class in the treatment of metastatic soft-tissue sarcomas.Keywords: soft-tissue sarcoma, pazopanib, tyrosine kinase inhibitor

Philippe A Cassier1, Armelle Dufresne1, Jean-Yves Blay1,2,3, Jérôme Fayette2,31Unité de Jour d’Oncologie Médicale Multidisciplinaire, Hôpital Edouard Herriot, Lyon, France; 2Département d’Oncologie Médicale, Centre Léon Bérard, Lyon, France; 3Unité INSERM 590, Equipe Cytokine et Cancer, Centre Léon Bérard, Lyon, FranceAbstract: Trabectedin is a new marine-derived compound that binds the DNA minor groove and interacts with proteins of the DNA repair machinery. Phase I trials have established the standard regimen as 1500 µg/m² 24-hour continuous infusion repeated every 3 weeks. Several phase II trials have shown response in 5%–10% of unselected patients with soft tissue sarcoma failing prior chemotherapy and disease stabilisation in 30%–40%. Furthermore, prolonged disease control has been described in 15%–20% of patients. Toxicities are mainly haematological and hepatic with grade 3–4 neutropenia and thrombocytopenia observed in approximately 50% and 20% of patients respectively, and grade 3–4 elevation of liver enzymes observed in 35%–50% of patients treated with trabectedin. Current research focuses on the identification of predictive factors for patients with soft tissue sarcoma treated with trabectedin.Keywords: chemotherapy, sarcoma, drug development, DNA repair

Brazilian public and private laboratories’ experience in copying ARVs since 1993 has been a technological learning process that in some cases has produced innovations. Reproducing drugs and synthesizing their active principles involves the combination of information available in patent documents and the partial rediscovery of certain know-how through laboratory manipulations. Chemists have to reconstruct the numerous “cat leaps” in patent documents, and in so doing often improve on the published processes or formulae. Generics laboratories are also able to use this knowledge base to invent new formulae, combinations of existing molecules, or to discover new molecules. Since 2000 the five laboratories studied have filed about ten patents on ARVs. We pieced together this technological learning process by interviewing chemists at generics laboratories, using the methods of the sociology of science.

In the prospect of engineering cyanobacteria for the biological photoproduction of hydrogen, we have studied the hydrogen production machine in the model unicellular strain Synechocystis PCC6803 through gene deletion, and overexpression (constitutive or controlled by the growth temperature). We demonstrate that the hydrogenase-encoding hoxEFUYH operon is dispensable to standard photoautotrophic growth in absence of stress, and it operates in cell defense against oxidative (H₂O₂) and sugar (glucose and glycerol) stresses. Furthermore, we showed that the simultaneous over-production of the proteins HoxEFUYH and HypABCDE (assembly of hydrogenase), combined to an increase in nickel availability, led to an approximately 20-fold increase in the level of active hydrogenase. These novel results and mutants have major implications for those interested in hydrogenase, hydrogen production and redox metabolism, and their connections with environmental conditions.

Little is known about the production of exopolysaccharides (EPS) in cyanobacteria, and there are no genetic and physiological evidences that EPS are involved in cell protection against the frequently encountered environmental stresses caused by salt and metals. We studied four presumptive EPS production genes, sll0923, sll1581, slr1875 and sll5052, in the model cyanobacterium Synechocystis PCC6803, which produces copious amounts of EPS attached to cells (CPS) and released in the culture medium (RPS) as shown here. We show that sll0923, sll1581, slr1875 and sll5052 are all dispensable to the growth of all corresponding single and double deletion mutants in absence of stress. Furthermore, we report that sll0923, sll1581 and slr1875 unambiguously operate in the production of both CPS and RPS. Both sll1581 and slr1875 are more important than sll0923 for CPS production, whereas the contrary is true for RPS production. We show that the most EPS-depleted mutant, doubly deleted for sll1581 and slr1875, lacks the EPS mantle that surrounds WT cells and sorbs iron in their vicinity. Using this mutant, we demonstrate for the first time that cyanobacterial EPS directly operate in cell protection against NaCl, CoCl(2), CdSO(4) and Fe-starvation. We believe that our EPS-depleted mutants will be useful tools to investigate the role of EPS in cell-to-cell aggregation, biofilm formation, biomineralization and tolerance to environmental stresses. We also suggest using the fast sedimenting mutants as biotechnological cell factories to facilitate the otherwise expensive harvest of the producer cell biomass and/or its separation from products excreted in the growth media.

Tumor genomic instability and selective treatment pressures result in clonal disease evolution; molecular stratification for molecularly targeted drug administration requires repeated access to tumor DNA. We hypothesized that circulating plasma DNA (cpDNA) in advanced cancer patients is largely derived from tumor, has prognostic utility, and can be utilized for multiplex tumor mutation sequencing when repeat biopsy is not feasible. We utilized the Sequenom MassArray System and OncoCarta panel for somatic mutation profiling. Matched samples, acquired from the same patient but at different time points were evaluated; these comprised formalin-fixed paraffin-embedded (FFPE) archival tumor tissue (primary and/or metastatic) and cpDNA. The feasibility, sensitivity, and specificity of this high-throughput, multiplex mutation detection approach was tested utilizing specimens acquired from 105 patients with solid tumors referred for participation in Phase I trials of molecularly targeted drugs. The median cpDNA concentration was 17 ng/ml (range: 0.5-1600); this was 3-fold higher than in healthy volunteers. Moreover, higher cpDNA concentrations associated with worse overall survival; there was an overall survival (OS) hazard ratio of 2.4 (95% CI 1.4, 4.2) for each 10-fold increase in cpDNA concentration and in multivariate analyses, cpDNA concentration, albumin, and performance status remained independent predictors of OS. These data suggest that plasma DNA in these cancer patients is largely derived from tumor. We also observed high detection concordance for critical 'hot-spot' mutations (KRAS, BRAF, PIK3CA) in matched cpDNA and archival tumor tissue, and important differences between archival tumor and cpDNA. This multiplex sequencing assay can be utilized to detect somatic mutations from plasma in advanced cancer patients, when safe repeat tumor biopsy is not feasible and genomic analysis of archival tumor is deemed insufficient. Overall, circulating nucleic acid biomarker studies have clinically important multi-purpose utility in advanced cancer patients and further studies to pursue their incorporation into the standard of care are warranted.

Due to the constant progress and exigencies of metalmechanics industries, they have been forced to look for highly accurate methods to predict a desired surface roughness value at a lower price. Although the grinding process, compared to other machining process (turning and milling), is a good one to remove material as well to obtain a good surface finish, requires a good control on the operative variables to guarantee a best surface finish. Based on the influence of the grinding cutting variables, such as, workpiece speed (Vp), down feed (d) and different hardness for an AISI 1045 and AISI 4140 steel, a simple mathematical model for roughness Ra was obtained in order to predict the value of roughness required for the established cutting conditions.

A experiência dos laboratórios brasileiros públicos e privados em copiar ARVs (anti-retrovirais), desde 1993, constitui um processo de aprendizado tecnológico que, em alguns casos, produziu inovações. Reproduzir medicamentos e sintetizar seus princípios ativos envolve a combinação de informações disponíveis em patentes e a redescoberta parcial de um certo know-how por meio de manipulações em laboratórios. Os químicos devem reconstituir os diversos “pulos-do-gato” existentes nas patentes e, ao fazê-lo, freqüentemente melhoram processos e fórmulas publicados. Os laboratórios de genéricos também estão aptos a utilizar essa base de conhecimento para criar novas fórmulas, combinações de moléculas existentes ou para descobrir novas moléculas. Desde 2000, os cinco laboratórios estudados registraram dez patentes de ARVs. Aos poucos, descobrimos esse processo de aprendizado tecnológico, por meio de entrevistas realizadas com químicos em laboratórios de genéricos, usando métodos da sociologia da ciência.

Abstract Background The role of surgery in the management of patients with advanced gastrointestinal stromal tumors (GIST) in the era of imatinib mesylate (IM) remains debated. We analyzed the outcome of patients with non metastatic locally advanced primary GIST treated with IM within the prospective BFR14 phase III trial. Methods The database of the BFR14 trial was searched for patients with no metastasis at time of inclusion. Patients treated for recurrent disease were excluded. Twenty-five of 434 patients met these criteria. Results Fifteen of 25 patients (60%) had a partial response to IM. Nine of the 25 patients (36%) underwent surgical resection of their primary tumor after a median of 7.3 months of IM treatment (range 3.4-12.0). Per protocol patients received continuous IM treatment in the post resection period, in an adjuvant setting. With a median follow-up of 53.5 months, there was a significant improvement in progression-free survival (PFS) and overall survival (OS) for patients who underwent surgical resection versus those who did not (median not reached vs 23.6 months, p = 0.0318 for PFS and median not reached vs 42.2 months, p = 0.0217 for OS). In the group of patients who underwent resection followed by IM, the 3-year PFS and OS rates were 67% and 89% respectively Conclusions Following neoadjuvant IM for non metastatic locally advanced GIST 9 of 25 patients (36%) were selected for resection of the primary tumor. OS and PFS figures were close to those of localised intermediate or high risk GIST (70% at 5 years) in the subgroup of operated patients, while the outcome of the non-operated subgroup was similar to that of metastatic GIST.