IMPROVED RISK STRATIFICATION IN MULTIPLE MYELOMA USING A MICRORNA-BASED CLASSIFIER

Introduction and purposes. Multiple myeloma (MM) is a heterogeneous disease. The discovery of a class of small non-coding RNAs (miRNAs) has revealed a new level of biological complexity underlying the regulation of gene expression. It may be possible to use this interesting new biology to improve our ability to risk stratify patients in the clinic. Methods and experimental design. We performed global miRNA expression profiling analysis of 163 primary tumors included in the UK Myeloma IX clinical trial. miRNA expression profiling was carried out using Affymetrix GeneChip miRNA 2.0; expression values for 847 hsa-miRNAs were extracted using Affymetrix miRNA QC tool and RMA-normalized. There are also 153 matching samples with gene expression profiles (GEP) and 72 matching cases with genotyping data available for integrative analyses. GEP was generated on Affymetrix HG-U133 Plus 2.0 and the expression values were RMA normalized; genotyping was performed on Affymetrix GeneChip Mapping 500K Array and the copy number values were obtained using GTYPE and dChip and were inferred against normal germ-line counterpart for each sample. Results. Firstly we have defined 8 miRNAs linked to 3 Translocation Cyclin D (TC) subtypes of MM with distinct prognoses, including miR-99b/let-7e/miR-125a upregulation and miR-150/miR-155/miR-34a upregulation in unfavourable 4p16 and MAF cases respectively as well as miR-1275 upregulation and miR-138 downregulation in favourable 11q13 cases. The expression levels of the miRNA cluster miR-99b/let-7e/miR-125a at 13q13 have been shown to be associated with shorter progression free survival in our dataset. Interestingly unsupervised hierarchical clustering analysis using these 8 miRNAs identified two subclusters among 11q13 cases, which have differential effect on overall survival (OS). We then evaluated the association of miRNA expression with OS and identified 3 significantly associated miRNAs (miR-17, miR-18 and miR-886-5p) after multiple testing corrections, either per se or in concerted fashion. We went on to develop an \u201coutcome classifier\u201d based on the expression of two miRNAs (miR-17 and miR-886-5p), which is able to stratify patients into three risk groups (median OS 19.4 months vs 40.6 months vs 65.3 months, log-rank test P = 0.001). The robustness of the miRNA-based classifier has been validated using 1000 bootstrap replications with an estimated error rate of 1.6%. The miRNA-stratified risk groups are independent from main adverse fluorescence in situ hybridization (FISH) abnormalities (1q gain, 17p deletion and t(4;14)), International Staging System (ISS) and Myeloma IX treatment arm (intensive or non-intensive). Using the miRNA-based classifier in the context of ISS/FISH risk stratification showed that it can significantly improve the predictive power (likelihood-ratio test P = 0.0005) and this classifier is also independent from GEP-derived prognostic signatures including UAMS, IFM and Myeloma IX 6-gene signature (P < 0.002). Integrative analyses didn't show enough evidence that the miRNAs comprising the classifier were deregulated via copy number changes; however, our data supported that the mir-17~92 cluster was activated by Myc and E2F3, highlighting the potential importance of Myc/E2F/miR-17~92 negative feedback loop in myeloma pathogenesis. We developed an approach to identify the putative targets of the OS-associated miRNAs and show that they regulate a large number of genes involved in MM biology such as proliferation, apoptosis, angiogenesis and drug resistance. Conclusion. In this study we developed a simple miRNA-based classifier to stratify patients into three risk groups, which is independent from current prognostic approaches in MM such as ISS, FISH abnormalities and GEP-derived signatures. The miRNAs comprising the classifier are biologically relevant and have been shown to regulate a large number of genes involved in MM biology. This is the first report to show that miRNAs can be built into molecular diagnostic strategies for risk stratification in MM

Altitude and vegetation affect soil organic carbon, basal respiration and microbial biomass in apennine forest soils

Both altitude and vegetation are known to affect the amount and quality of soil organic matter (SOM) and the size and activity of soil microbial biomass. However, when altitude and vegetation changes are combined, it is still unclear which one has a greater effect on soil chemical and biochemical properties. With the aim of clarifying this, we tested the effect of altitude (and hence temperature) and vegetation (broadleaf vs pine forests) on soil organic carbon (SOC) and soil microbial biomass and its activity. Soil sampling was carried out in two adjacent toposequences ranging from 500 to 1000ma.s.l. on a calcareous massif in central Italy: one covered only by Pinus nigra J.F. Arnold forests, while the other covered by Quercus pubescens Willd., Ostrya carpinifolia Scop. and Fagus sylvatica L. forests, at 500, 700 and 1000 m a.s.l., respectively. The content of SOC and water-extractable organic carbon (WEOC) increased with altitude for the pine forests, while for the broadleaf forests no trend along the slope occurred, and the highest SOC and WEOC contents were observed in the soil at 700 m under the Ostrya carpinifolia forest. With regard to the soil microbial community, although the size of the soil microbial biomass (Cmic) generally followed the SOC contents along the slope, both broadleaf and pine forest soils showed similar diminishing trends with altitude of soil respiration (\u3a3CO2-C), and \u3a3CO2-C:WEOC and \u3a3CO2-C:Cmic ratios. The results pointed out that, although under the pine forests' altitude was effective in affecting WEOC and SOC contents, in the soils along the broadleaf forest toposequence this effect was absent, indicating a greater impact of vegetation than temperature on SOC amount and pool distribution. Conversely, the similar trend with altitude of the microbial activity indexes would indicate temperature to be crucial for the activity of the soil microbial community

Utilização de fibras vegetais para reforço de plásticos.

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Beef Heifers Performance under Continuous Grazing on Modified Grassland in Argentina Flooding Pampa

The Salado river basin is the main beef cattle breeding region of Argentina. It is a flat flooding area with poor slopes (\u3c 3%). Their soils are Natracuoles, Natraqualfes and Argiacuoles. The grasslands are predominately continuously grazed and with a set stocking rate cow – calf system. Stocking rate and grazing pressure are two core variables that directly affect animal production. Reduced animal performance is believed to be due to poor grazing management. During 2010, 2011 and 2012 an experiment on the effect of stocking rate on animal growth and body condition with Angus heifers continuously grazing annual winter grasses, was carried out. Previous studies have demonstrated the practicability of producing replacement females with this management (Carrillo 2001; Eirin et al. 2011; Agnelli et al. 2011) that involves mesothermic grasslands modification into self sown winter grasses by using glyphosate and other herbicides (Oyhamburu et al. 2000, Rodriguez and Jacobo 2010). The aim of this study was to establish the stocking rate that optimizes beef rearing heifer’s performance for early mating

Effects of Continuous Grazing and Exclusion on the Structure of Modified Flooding Pampa Grassland in Argentina

The breeding of beef cattle is the predominant activity in the Flooding Pampa wet grasslands. The stocking rate of this region is increasing because of livestock displaced by agriculture in other regions. This increased load has been achieved through the alteration of grassland with the use of herbicides and fertilizers or replacement thereof by pasture (Cahuepé and Hidalgo 2005). The large herbivores grazing cause changes in species composition and diversity (Hall et al. 1986) in both the original and the modified grassland. The aim of this study was to evaluate the effects of different stocking rates under continuous grazing and exclusion of grazing on the floristic composition and diversity of wet mesophytes prairie, modified during 10 years by the application of herbicides

Amido termoplástico.

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