IntroductionAutologous fat grafting is commonly used to correct soft-tissue contour deformities. However, results are impaired by a variable and unpredictable resorption rate. Autologous adipose-derived stromal cells in combination with lipoinjection (cell-assisted lipotransfer) seem to favor a long-term persistence of fat grafts, thus fostering the development of devices to be used in the operating room at the point of care, to isolate the stromal vascular fraction (SVF) and produce SVF-enhanced fat grafts with safe and standardized protocols. Focusing on patients undergoing breast reconstruction by lipostructure, we analyzed a standard technique, a modification of the Coleman’s procedure, and three different commercially available devices (Lipokit, Cytori, Fastem), in terms of 1) ability to enrich fat grafts in stem cells and 2) clinical outcome at 6 and 12 months.MethodsTo evaluate the ability to enrich stem cells, we compared, for each patient (n = 20), the standard lipoaspirate with the respective stem cell-enriched one, analyzing yield, immunophenotype and colony-forming capacity of the SVF cells as well as immunophenotype, clonogenicity and multipotency of the obtained adipose stem cells (ASCs). Regarding the clinical outcome, we compared, by ultrasonography imaging, changes at 6 and 12 months in the subcutaneous thickness of patients treated with stem-cell enriched (n = 14) and standard lipoaspirates (n = 16).ResultsBoth methods relying on the enzymatic isolation of primitive cells led to significant increase in the frequency, in the fat grafts, of SVF cells as well as of clonogenic and multipotent ASCs, while the enrichment was less prominent for the device based on the mechanical isolation of the SVF. From a clinical point of view, patients treated with SVF-enhanced fat grafts demonstrated, at six months, a significant superior gain of thickness of both the central and superior-medial quadrants with respect to patients treated with standard lipotransfer. In the median-median quadrant the effect was still persistent at 12 months, confirming an advantage of lipotransfer technique in enriching improving long-term fat grafts.ConclusionsThis comparative study, based on reproducible biological and clinical parameters and endpoints, showed an advantage of lipotransfer technique in enriching fat grafts in stem cells and in favoring, clinically, long-term fat grafts.Electronic supplementary materialThe online version of this article (doi:10.1186/scrt536) contains supplementary material, which is available to authorized users.

Background: Translational medicine aims at transferring advances in basic science research into new approaches for diagnosis and treatment of diseases. Low-grade gliomas (LGG) have a heterogeneous clinical behavior that can be only partially predicted employing current state-of-theart markers, hindering the decision-making process. To deepen our comprehension on tumor heterogeneity, we dissected the mechanism of interaction between tumor cells and relevant components of the neoplastic environment, isolating, from LGG and high-grade gliomas (HGG), proliferating stem cell lines from both the glioma stroma and, where possible, the neoplasm. Methods and Findings: We isolated glioma-associated stem cells (GASC) from LGG (n540) and HGG (n573). GASC showed stem cell features, anchorage-independent growth, and supported the malignant properties of both A172 cells and human glioma-stem cells, mainly through the release of exosomes. Finally, starting from GASC obtained from HGG (n513) and LGG (n512) we defined a score, based on the expression of 9 GASC surface markers, whose prognostic value was assayed on 40 subsequent LGG-patients. At the multivariate Cox analysis, the GASCbased score was the only independent predictor of overall survival and malignant progression free-survival. Conclusions: The microenvironment of both LGG and HGG hosts non-tumorigenic multipotent stem cells that can increase in vitro the biological aggressiveness of gliomainitiating cells through the release of exosomes. The clinical importance of this finding is supported by the strong prognostic value associated with the characteristics of GASC. This patientbased approach can provide a groundbreaking method to predict prognosis and to exploit novel strategies that target the tumor stroma.

This study demonstrates for the first time the independent prognostic role of NF-kB activation in LGG and outlines the role of patient-based stem cell models as a tool for precision medicine approaches.

BackgroundTransposable elements (TEs) are DNA sequences able to mobilize themselves and to increase their copy-number in the host genome. In the past, they have been considered mainly selfish DNA without evident functions. Nevertheless, currently they are believed to have been extensively involved in the evolution of primate genomes, especially from a regulatory perspective. Due to their recent activity they are also one of the primary sources of structural variants (SVs) in the human genome. By taking advantage of sequencing technologies and bioinformatics tools, recent surveys uncovered specific TE structural variants (TEVs) that gave rise to polymorphisms in human populations. When combined with RNA-seq data this information provides the opportunity to study the potential impact of TEs on gene expression in human.ResultsIn this work, we assessed the effects of the presence of specific TEs in cis on the expression of flanking genes by producing associations between polymorphic TEs and flanking gene expression levels in human lymphoblastoid cell lines. By using public data from the 1000 Genome Project and the Geuvadis consortium, we exploited an expression quantitative trait loci (eQTL) approach integrated with additional bioinformatics data mining analyses. We uncovered human loci enriched for common, less common and rare TEVs and identified 323 significant TEV-cis-eQTL associations. SINE-R/VNTR/Alus (SVAs) resulted the TE class with the strongest effects on gene expression. We also unveiled differential functional enrichments on genes associated to TEVs, genes associated to TEV-cis-eQTLs and genes associated to the genomic regions mostly enriched in TEV-cis-eQTLs highlighting, at multiple levels, the impact of TEVs on the host genome. Finally, we also identified polymorphic TEs putatively embedded in transcriptional units, proposing a novel mechanism in which TEVs may mediate individual-specific traits.ConclusionWe contributed to unveiling the effect of polymorphic TEs on transcription in lymphoblastoid cell lines.

Low-grade gliomas (LGG) are infiltrative primary brain tumors that in 70% of the cases undergo anaplastic transformation, deeply affecting prognosis. However, the timing of progression is heterogeneous. Recently, the tumor microenvironment (TME) has gained much attention either as prognostic factor or therapeutic target. Through the release of extracellular vesicles, the TME contributes to tumor progression by transferring bioactive molecules such as microRNA. The aim of the study was to take advantage of glioma-associated stem cells (GASC), an in vitro model of the glioma microenvironment endowed with a prognostic significance, and their released exosomes, to investigate the possible role of exosome miRNAs in favoring the anaplastic transformation of LGG. Therefore, by deep sequencing, we analyzed and compared the miRNA profile of GASC and exosomes obtained from LGG patients characterized by different prognosis. Results showed that exosomes presented a different signature, when compared to their cellular counterpart and that, although sharing several miRNAs, exosomes of patients with a bad prognosis, selectively expressed some miRNAs possibly responsible for the more aggressive phenotype. These findings get insights into the value of TME and exosomes as potential biomarkers for precision medicine approaches aimed at improving LGG prognostic stratification and therapeutic strategies.