Prognostic significance of miR-34a in Ewing sarcoma is associated with cyclin D1 and ki-67 expression

BACKGROUND: At diagnosis, identification of reliable biological indicators of prognosis to allow stratification of patients according to different risks is an important but still unresolved aspect in the treatment of Ewing sarcoma (EWS) patients. This study aimed to explore the role of miR-34A expression on prognosis of EWS patients.PATIENTS AND METHODS: Specimens from 109 patients with non-metastatic EWS treated at the Rizzoli Institute with neoadjuvant chemotherapy (protocols ISG/SSGIII, EW-1, EW-2, EW-REN2, EW-REN3, EW-PILOT) and 17 metastases were studied. Sixty-eight patients (62%) remained disease-free and 41 (38%) relapsed (median follow-up: 67 months, range 9-241 months). Expression of miR-34a and of some of its targets (cyclin D1, bcl-2, SIRT1 and YY1) was evaluated by qRT-PCR using TaqMan MicroRNA Assays and/or by immunohistochemistry on tissue microarrays from the same patients.RESULTS: High expression of miR-34a in localized tumors was significantly related to better event-free and overall survival (P = 0.004). Relevance of miR-34a was confirmed by using different calibrators (normal mesenchymal stem cells and different normal tissues). By multivariate Cox regression analysis, low miR-34a expression as well as nontotal necrosis and high levels of lactate dehydrogenase were all confirmed as independent risk factors associated with poor outcome. Expression of miR-34a was lower in metastases than in primary tumors. It inversely correlated with expression of cyclin D1 and Ki-67.CONCLUSIONS: By demonstrating its relationship with clinical outcome, we propose evaluation of miR-34a at diagnosis of EWS patients to allow early risk stratification. Validation of these results would nonetheless ultimately need a prospective assessment

MESOZOOPLANKTON AND MACROZOOPLANKTON COMPOSITION PATTERNS RELATED TO HYDRODYNAMIC STRUCTURES IN THE LIGURIAN SEA (TROPHOS-2 EXPERIMENT, APRIL-JUNE-1986)

International audienceThe distributional patterns of zooplanktonic fauna based on samples taken during the Trophos-2 cruise (spring 1986) in the western Liguro-Provencal Basin, Mediterranean Sea, are described. This region is permanently exposed to a cyclonic circulation with an associated thermohaline front which encloses a central divergence zone. In the middle of this central area, we encountered a mesoscale (about 70 km diameter) anticyclonic eddy. Taking into account the hydrological structure of the 0 to 200 m upper level, the area could be divided into 4 zones: (1) peripheral and frontal, (2) central Riviera, (3) central Corsica and (4) the eddy. These zones differed in the abundance of several zooplankton species. In particular, some of them showed a higher concentration in the eddy, such as the radiolarian Aulacantha scolymantha, the euphausiid calyptopis larvae, and the copepods Centropages typicus, Pleuromamma gracilis, Mesocalanus tenuicornis, Heterorhabdus papilliger and Euchirella rostrata. We suggest the central eddy is a favorable environment for these large species. Thus, increased primary and secondary production due to the influence of hydrodynamic phenomena appears not to be Limited to the frontal zone. Within the eddy, zooplankton growth could be enhanced, thus favoring export production. To detect zooplankton species assemblages, the stations have been clustered into 5 groups based on their taxonomic composition and abundance. These groups had a rather good geographic coherence although they had a more complex distribution than the physical structure. This higher variability of spatial organization of the 5 plankton assemblages can be explained by behavioral and trophic phenomena

Zooplankton community structure in the Western Mediterranean sea related to mesoscale hydrodynamics

International audienceIn the Liguro-provencal basin (Northwestern Mediterranean sea), an heterogeneous hydrodynamic structure was observed in May 1986 (Pinca & Dallot, 1995). The hydrological system was characterized, as usual for this region, by the cyclonic Ligurian current with its associated thermohaline coastal fronts separating the coastal area from a central divergence zone, but was complicated in 1986 by the presence of an anticyclonic eddy in the middle of the central area. The sampling sites were consequently separated into four zones according to this physical structure. Mesozooplankton community structure related to the physical organization of the water masses is presented here. In order to obtain a description of the community structure, we studied both structure indices (species richness, evenness, dominance) and Rank-Frequency Diagrams. These descriptors showed a certain patchiness: species diversity and evenness were both minimal in the central area and increased towards the zones that surrounded the eddy and the coastal regions. However, almost everywhere we observed a stage 1 in the ecological succession as depicted by Frontier (1976), indicating that the development of the community structure (Margalef, 1967) was still at a juvenile state, else, that it was disturbed by the rapidly growing population of a single species. The most striking characteristic of the data set was actually the strong predominance of one or two copepod species. Centropages typicus prevailed: its population increased during the spring bloom, particularly in the area of the anticyclonic eddy. In order to better identify the organization of the region in terms of different ecological maturity stages and to search for a relation between mesoscale physical structure and community patterns, we grouped the sites on the basis of relative abundance of ranked species. We used an agglomerative cluster analysis with a new dissimilarity index, corrected to limit the weight of the most abundant species. We then tested for differences among the seven obtained groups in terms of structure indices, biological and environmental parameters. The physical environment could be related to the organization of the plankton community. In the central area, where the divergence and the eddy were located, a higher concentration of phytoplankton, total mesozooplankton abundance and biomass were recorded. The eddy was characterized by a higher concentration of relatively bigger and omnivorous copepods (Euchirella rostrata, Pleuromamma gracilis, Centropages typicus), probably favored by their stronger swimming ability in this highly energetic environment. However, the more specific organization of the community was regulated by more complicated biological interrelations that gave rise to a higher level of patchiness in the ecological structure

Bikini Atoll coral biodiversity resilience five decades after nuclear testing

Five decades after a series of nuclear tests began, we provide evidence that 70% of the Bikini Atoll zooxanthellate coral assemblage is resilient to large-scale anthropogenic disturbance. Species composition in 2002 was assessed and compared to that seen prior to nuclear testing. A total of 183 scleractinian coral species was recorded, compared to 126 species recorded in the previous study (excluding synonomies, 148 including synonomies). We found that 42 coral species may be locally extinct at Bikini. Fourteen of these losses may be pseudo-losses due to inconsistent taxonomy between the two studies or insufficient sampling in the second study, however 28 species appear to represent genuine losses. Of these losses, 16 species are obligate lagoonal specialists and 12 have wider habitat compatibility. Twelve species are recorded from Bikini for the first time. We suggest the highly diverse Rongelap Atoll to the east of Bikini may have contributed larval propagules to facilitate the partial resilience of coral biodiversity in the absence of additional anthropogenic threats

Reef sponges as hosts of biodiversity: cases from North Sulawesi

A wide range of associations between sponges and other taxa is reported from all biogeographic regions of the world but their occurrence is strongly evident mainly in tropical areas. Some examples are here presented from the Marine Protected Area of Bunaken (North Sulawesi, Indonesia), considering relationships between sponges and polychaetes, barnacles, octocorals and algae. The examples show a wide range of relationships, from cases in which the two partners live together but independently, to relationships in which the two partners are deeply interconnected to form a unique symbiotic super-organism. We suggest that sponges should be considered as a hotspot of biodiversity not only for the huge number of hidden organisms they host, very often still undescribed, but also for the complex evolutionary histories that generally characterize these associations

Reef sponges as hosts of biodiversity: cases from North Sulawesi

Suzuki Y., Nakamori T., Hidaka M., Kayanne H., Casareto B.E., Nadao K., Yamano H., Tsuchiya M. (eds

Community analysis of reef habitats in the Marshall Islands

Between summer 2001 and 2003 three scientific expeditions were organized in four different atolls of the Marshall Islands as part of a research project aiming to assess marine resources in the whole country. Two atolls were explored in 2003, Rongelap in the north and Mili in the\ud south of the country. Information on corals and fish\ud abundances is presented here for a description of the coral\ud reef communities and comparison of the ecological differences between the two locations. Clear variability of\ud community composition inside an atoll is already evident\ud from the first in situ observation, outer ocean sites being\ud very different from lagoonal locations for both coral and fish composition. At a more detailed scale, the surveyed sites show differences in community composition, supported both through an a posteriori study based on their geographical location and exposure to the main current and surface wind, as well as through an CI priori multivariate analysis of the community. However. this latter analysis does not show a clear relationship between the fish species composition and the substrate or coral species composition. This is most probably due to other effects than just habitat and food availability in the constitution of a complex community such the one found in coral reefs

Paracentral corneal melting in a patient with Vogt-Koyanagi-Harada's syndrome, psoriasis, and Hashimoto thyroiditis

The paper describes the occurrence of unilateral paracentral corneal melting in a 65-year-old woman with ocular and systemic signs of Vogt-Koyanagi-Harada’s syndrome (VKH), psoriasis, and Hashimoto’s thyroiditis. Corneal melting, often occurring in association with systemic vasculitis and connective tissue diseases, has rarely been reported in relation to diffuse psoriasis and never in association with VKH.A possible relationship between corneal melting and VKH is suggested