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Patient-derived xenografts (PDXs) are resected human tumors engrafted into mice for preclinical studies and therapeutic testing. It has been proposed that the mouse host affects tumor evolution during PDX engraftment and propagation, affecting the accuracy of PDX modeling of human cancer. Here, we exhaustively analyze copy number alterations (CNAs) in 1,451 PDX and matched patient tumor (PT) samples from 509 PDX models. CNA inferences based on DNA sequencing and microarray data displayed substantially higher resolution and dynamic range than gene expression-based inferences, and they also showed strong CNA conservation from PTs through late-passage PDXs. CNA recurrence analysis of 130 colorectal and breast PT/PDX-early/PDX-late trios confirmed high-resolution CNA retention. We observed no significant enrichment of cancer-related genes in PDX-specific CNAs across models. Moreover, CNA differences between patient and PDX tumors were comparable to variations in multiregion samples within patients. Our study demonstrates the lack of systematic copy number evolution driven by the PDX mouse host., Analysis of copy number alterations in 1,451 patient-derived xenografts (PDXs) and matched patient tumor samples shows strong conservation from patient tumors through late-passage PDXs and a lack of systematic copy number evolution driven by the mouse host.

Colorectal cancer (CRC) biopsies underpin accurate diagnosis, but are also relevant for patient stratification in molecularly‐guided clinical trials. The consensus molecular subtypes (CMSs) and colorectal cancer intrinsic subtypes (CRISs) transcriptional signatures have potential clinical utility for improving prognostic/predictive patient assignment. However, their ability to provide robust classification, particularly in pretreatment biopsies from multiple regions or at different time points, remains untested. In this study, we undertook a comprehensive assessment of the robustness of CRC transcriptional signatures, including CRIS and CMS, using a range of tumour sampling methodologies currently employed in clinical and translational research. These include analyses using (i) laser‐capture microdissected CRC tissue, (ii) eight publically available rectal cancer biopsy data sets (n = 543), (iii) serial biopsies (from AXEBeam trial, NCT00828672; n = 10), (iv) multi‐regional biopsies from colon tumours (n = 29 biopsies, n = 7 tumours), and (v) pretreatment biopsies from the phase II rectal cancer trial COPERNCIUS (NCT01263171; n = 44). Compared to previous results obtained using CRC resection material, we demonstrate that CMS classification in biopsy tissue is significantly less capable of reliably classifying patient subtype (43% unknown in biopsy versus 13% unknown in resections, p = 0.0001). In contrast, there was no significant difference in classification rate between biopsies and resections when using the CRIS classifier. Additionally, we demonstrated that CRIS provides significantly better spatially‐ and temporally‐ robust classification of molecular subtypes in CRC primary tumour tissue compared to CMS (p = 0.003 and p = 0.02, respectively). These findings have potential to inform ongoing biopsy‐based patient stratification in CRC, enabling robust and stable assignment of patients into clinically‐informative arms of prospective multi‐arm, multi‐stage clinical trials. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Anaplastic large-cell lymphomas (ALCLs) are a group of clinically and biologically heterogeneous diseases including the ALK(+) and ALK(-) systemic forms. Whereas ALK(+) ALCLs are molecularly characterized and can be readily diagnosed, specific immunophenotypic or genetic features to define ALK(-) ALCL are missing, and their distinction from other T-cell non-Hodgkin lymphomas (T-NHLs) remains controversial. In the present study, we undertook a transcriptional profiling meta-analysis of 309 cases, including ALCL and other primary T-NHL samples. Pathway discovery and prediction analyses defined a minimum set of genes capable of recognizing ALK(-) ALCL. Application of quantitative RT-PCR in independent datasets from cryopreserved and formalin-fixed paraffin-embedded samples validated a 3-gene model (TNFRSF8, BATF3, and TMOD1) able to successfully separate ALK(-) ALCL from peripheral T-cell lymphoma not otherwise specified, with overall accuracy near 97%. In conclusion, our data justify the possibility of translating quantitative RT-PCR protocols to routine clinical settings as a new approach to objectively dissect T-NHL and to select more appropriate therapeutic protocols. (Blood. 2012;120(6):1274-1281) Anaplastic large-cell lymphomas (ALCLs) are a group of clinically andbiologically heterogeneous diseases including the ALK(+) and ALK(-) systemicforms. Whereas ALK(+) ALCLs are molecularly characterized and can be readilydiagnosed, specific immunophenotypic or genetic features to define ALK(-) ALCLare missing, and their distinction from other T-cell non-Hodgkin lymphomas(T-NHLs) remains controversial. In the present study, we undertook atranscriptional profiling meta-analysis of 309 cases, including ALCL and otherprimary T-NHL samples. Pathway discovery and prediction analyses defined aminimum set of genes capable of recognizing ALK(-) ALCL. Application ofquantitative RT-PCR in independent datasets from cryopreserved and formalin-fixedparaffin-embedded samples validated a 3-gene model (TNFRSF8, BATF3, and TMOD1)able to successfully separate ALK(-) ALCL from peripheral T-cell lymphoma nototherwise specified, with overall accuracy near 97%. In conclusion, our datajustify the possibility of translating quantitative RT-PCR protocols to routineclinical settings as a new approach to objectively dissect T-NHL and to selectmore appropriate therapeutic protocols

The advent of Next Generation Sequencing (NGS) technology has enabled a new major approach for micro RNAs (miRNAs) expression profiling through the so called RNA-Sequencing (RNA-Seq). Different tools have been developed in the last years in order to detect and quantify miRNAs, especially in pathological samples, starting from the big amount of data deriving from RNA sequencing. These tools, usually relying on general purpose alignment algorithms, are however characterized by different sensitivity and accuracy levels and in the most of the cases provide not overlapping predictions. To overcome these limitations we propose a novel pipeline for miRNAs detection and quantification in RNA-Seq sample, miRNA Seed Extension Aligner (miR-SEA), based on an experimental evidence concerning miRNAs structure. The proposed pipeline was tested on three Colorectal Cancer (CRC) RNA-Seq samples and the obtained results compared with those provided by two well-known miRNAs detection tools showing good ability in performing detection and quantification more adherent to miRNAs structure.

In tissue engineering, several factors play key roles in providing adequate stimuli for cells differentiation, in particular biochemical and physical stimuli, which try to mimic the physiological microenvironments. Since electrical stimuli are important in the developing heart, we have developed an easy-to-use, cost-effective cell culture platform, able to provide controlled electrical stimulation aimed at investigating the influence of the electric field in the stem cell differentiation process. This bioreactor consists of an electrical stimulator and 12 independent, petri-like culture chambers and a 3-D computational model was used to characterize the distribution and the intensity of the electric field generated in the cell culture volume. We explored the effects of monophasic and biphasic square wave pulse stimulation on a mouse adipose-derived stem cell line (m17.ASC) comparing cell viability, proliferation, protein, and gene expression. Both monophasic (8 V, 2 ms, 1 Hz) and biphasic (+4 V, 1 ms and -4 V, 1 ms; 1 Hz) stimulation were compatible with cell survival and proliferation. Biphasic stimulation induced the expression of Connexin 43, which was found to localize also at the cell membrane, which is its recognized functional mediating intercellular electrical coupling. Electrically stimulated cells showed an induced transcriptional profile more closely related to that of neonatal cadiomyocytes, particularly for biphasic stimulation. The developed platform thus allowed to set-up precise conditions to drive adult stem cells toward a myocardial phenotype solely by physical stimuli, in the absence of exogenously added expensive bioactive molecules, and can thus represent a valuable tool for translational applications for heart tissue engineering and regeneration.

Dimethyl Disulfide (DMDS), as an EC formulation, was applied via drip-irrigation to control the root-knot nematode Meloidogyne incognita in two trials in protected crops. The trials were carried out in Sicily (Italy) during 2012 on melon and on tomato, according to a randomized block design with 4-5 replicates per treatment. The soil of the sites was sandy and naturally severely infested by the nematode. DMDS was applied at the rates of 300, 400, and 500 kg/ha (the last rate only in tomato). The soil was covered with virtually impermeable film (VIF) before fumigation and uncovered 2 weeks later. DMDS treatments were compared with 1,3-dichloropropene (140 L/ha for melon and 180 L/ha for tomato) and a non-treated control. Yield was recorded in all trials. The nematode attack on the roots was evaluated according to the 0-10 Zeck's scale modified (0 no galls and 10 root system completely deformed by large and numerous galls). In the melon trial, 60 days after transplanting (DAT), both DMDS doses (400 and 300 kg/ha) showed low root gall indices (1.2 and 1.5, respectively), compared to the non-treated control (5.5) and 1,3-dichloropropene (4.2). In the tomato trial 120 DAT, DMDS at 500, 400 and 300 kg/ha showed root gall indices of 2.9, 2.7, and 3.0, respectively, compared to 9.6 of the non-treated control and 3.6 of 1,3-dichloropropene. All nematicidal treatments significantly increased marketable yields of melon and tomato in comparison to non-treated controls. Therefore, DMDS, once registered, could be a new effective solution to control root-knot nematodes in protected crops and because of its favourable ecotoxicologial profile, it could also be considered for IPM programmes of protected crops.

The receptor tyrosine kinases (RTKs) play a critical role, controlling cell proliferation, survival, and differentiation of normal cells. Their pivotal function has been firmly established in the pathogenesis of many cancers as well. The anaplastic lymphoma kinase (ALK), a transmembrane RTK, originally identified in the nucleophosmin (NPM)–ALK chimera of anaplastic large cell lymphoma, has emerged as a novel tumorigenic player in several human cancers. In this review, we describe the expression of the ALK–RTK, its related fusion proteins, and their molecular mechanisms of activation. Novel tailored strategies are briefly illustrated for the treatment of ALK-positive neoplasms.