Genomic analysis of single cytokeratin-positive cells from bone marrow reveals early mutational events in breast cancer

SummaryChromosomal instability in human breast cancer is known to take place before mammary neoplasias display morphological signs of invasion. We describe here the unexpected finding of a tumor cell population with normal karyotypes isolated from bone marrow of breast cancer patients. By analyzing the same single cells for chromosomal aberrations, subchromosomal allelic losses, and gene amplifications, we confirmed their malignant origin and delineated the sequence of genomic events during breast cancer progression. On this trajectory of genomic progression, we identified a subpopulation of patients with very early HER2 amplification. Because early changes have the highest probability of being shared by genetically unstable tumor cells, the genetic characterization of disseminated tumor cells provides a novel rationale for selecting patients for targeted therapies

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Soil Organic Matter Composition in Coastal and Continental Date Palm Systems: Insights from Tunisian Oases

In Tunisia, the coastal oasis of Chenini is characterized by a lush vegetation cover, while more inland continental oases (e.g. Guettaya oasis) have a very scarce vegetation cover. For sustaining date production, organic fertilizer is applied, either spread on the soil surface (in Chenini) or buried under a sand layer (in Guettaya). We examined on a molecular level how these management techniques affect soil organic matter composition in oasis systems. 13C nuclear magnetic resonance spectroscopy signals indicated for Guettaya a dominance of fresh plant input, which was most pronounced in the uppermost soil close to palms. Evidence of more degraded organic matter was found in deeper soil near the palms, as well as in soil more distant from palms. Amino sugar analysis revealed lower contents in the uppermost Guettaya soil near the palms. The overall microbial amino sugar residue contents were similar in range as those found in other dryland environments. With increased distance from trees the amino sugar contents declined in Guettaya where the palms grow on the bare soil but this was not the case for Chenini with multi-layer vegetation cover under the date palms. In agreement with previous dryland studies, the soil microbial community in both oasis systems was dominated by fungi in topsoil, but shifted towards bacteria-derived residues in subsurface soil. This might be due to higher variability of temperature and moisture in topsoil and/or lower degradability of fungal remains, but here further research is required

The implementation of taxonomic harmonisation for Candoninae (Ostracoda, Cypridoidea): A heuristic solution for Fabaeformiscandona tricicatricosa (Diebel and Pietrzeniuk)

International audienceThe concept of Taxonomic Harmonisation (TH) incorporates the search for similarities between taxa mentioned in different data sets and/or taxonomic classification systems, in order to propose a more coherent and homogenous taxonomic system necessary for practical usage in basic and applied scientific activities. For the present project we conceived Fabaeformiscandona tricicatricosa as a species defined by a homeostatic cluster of traits with a given temporal persistence, visible in close relationship with other Fabaeformiscandonaspecies, like F. caudata(Kaufmann), F. levanderi (Hirschmann), and F. siliquosa(Brady), as well as with Candona neglecta Sars which displays analogies in valve shape. We show the advantages to study the above-mentioned taxa by a combination of classic observations in optical microscopy with SEM-techniques and with the treatment of data using geometric morphometrics and multivariate statistics. A protocol for the implementation of the TH of F. tricicatricosa is proposed. We offer a differential diagnosis for F. tricicatricosaas compared to F. caudata, F. levanderi, F. siliquosaand C. neglecta. We use for taxonomic diagnostics a combination of aggregate traits like the average of the outline of valves and qualitative traits, like the shape and the position of a ledge on the posterior side of the valves. We propose to add the term “Consensus” to the species defined by the procedure of the taxonomic harmonisation. To differentiate them from other types of species we propose to use the extension sensu lato following the Linnean species notation. Comments on the origin and the (palaeo)ecology and (palaeo)biogeography of F. tricicatricosaare presented

Molecular Mechanisms by Which a Fucus vesiculosus Extract Mediates Cell Cycle Inhibition and Cell Death in Pancreatic Cancer Cells

Pancreatic cancer is one of the most aggressive cancer entities, with an extremely poor 5-year survival rate. Therefore, novel therapeutic agents with specific modes of action are urgently needed. Marine organisms represent a promising source to identify new pharmacologically active substances. Secondary metabolites derived from marine algae are of particular interest. The present work describes cellular and molecular mechanisms induced by an HPLC-fractionated, hydrophilic extract derived from the Baltic brown seaweed Fucus vesiculosus (Fv1). Treatment with Fv1 resulted in a strong inhibition of viability in various pancreatic cancer cell lines. This extract inhibited the cell cycle of proliferating cells due to the up-regulation of cell cycle inhibitors, shown on the mRNA (microarray data) and protein level. As a result, cells were dying in a caspase-independent manner. Experiments with non-dividing cells showed that proliferation is a prerequisite for the effectiveness of Fv1. Importantly, Fv1 showed low cytotoxic activity against non-malignant resting T cells and terminally differentiated cells like erythrocytes. Interestingly, accelerated killing effects were observed in combination with inhibitors of autophagy. Our in vitro data suggest that Fv1 may represent a promising new agent that deserves further development towards clinical application