Project description:To determine if the influenza B virus HA is under constraints that limit its antigenic variation, we performed a transposon screen to compare the mutational tolerance of the currently circulating influenza A virus HAs (H1 and H3 subtypes) and influenza B virus HAs (B/Victoria87 and B/Yamagata88 antigenic lineages). A library of insertional mutants for each HA was generated and deep sequenced after passaging to determine where insertions were tolerated in replicating viruses.
Project description:We used expression profiling, SNP arrays, and mutational profiling to investigate a well-characterized cohort of MPN patients. MPN patients with homozygous JAK2V617F mutations were characterized by a distinctive transcriptional profile. Notably, a transcriptional signature consistent with activated JAK2 signaling is seen in all MPN patients regardless of clinical phenotype or mutational status. In addition, the activated JAK2 signature was present in patients with somatic CALR mutations. Conversely, we identified a gene expression signature of CALR mutations; this signature was significantly enriched in JAK2-mutant MPN patients consistent with a shared mechanism of transformation by JAK2 and CALR mutations. We also identified a transcriptional signature of TET2 mutations in MPN patent samples. Our data indicate that MPN patients, regardless of diagnosis or JAK mutational status are characterized by a distinct gene expression signature with upregulation of JAK-STAT target genes, demonstrating the central importance of the JAK-STAT pathway in MPN pathogenesis. [MPN patients] We have performed microarray gene expression analysis in 93 patients with MPNs (28 PV, 47 ET, 18 MF) and 11 age-matched normal donors.
Project description:RNA-Sequencing analysis of 18 papillary thyroid carcinoma biopsies and of 4 healthy donors' thyroids. In this analysis we assessed differential gene expression and investigated the mutational landscape in this tumor type. Analysis of gene fusion was also performed, leading to the identification of a novel chimeric transcript, potential driver in tumor initiation. Total RNA isolated from 18 papillary thyroid carcinoma biopsies and 4 healthy donors' thyroids.
Project description:The presence of diffuse anaplasia in Wilms tumours (DAWT) is associated with TP53 mutations and poor outcome. As patients receive intensified treatment, we sought to identify whether TP53 mutational status confers additional prognostic information. We studied 40 patients with DAWT with anaplasia in the tissue from which DNA was extracted and analysed for TP53 mutations and 17p loss. The majority of cases were profiled by copy number (n=32) and gene expression (n=36) arrays. TP53 mutational status was correlated with patient event-free and overall survival, genomic copy number instability and gene expression profiling. From the 40 cases, 22 (55%) had TP53 mutations (2 detected only after deep-sequencing), 20 of which also had 17p loss (91%); 18 (45%) cases had no detectable mutation but three had 17p loss. Tumours with TP53 mutations and/or 17p loss (n=25) had an increased risk of recurrence as a first event (p=0.03, hazard ratio (HR), 3.89; 95% confidence interval (CI), 1.26-16.0) and death (p=0.04, HR, 4.95; 95% CI, 1.36-31.7) compared to tumours lacking TP53 abnormalities. DAWT carrying TP53 mutations showed increased copy number alterations compared to those with wild-type, suggesting a more unstable genome (p=0.03). These tumours showed deregulation of genes associated with cell cycle and DNA repair biological processes. This study provides evidence that TP53 mutational analysis improves risk stratification in DAWT. This requires validation in an independent cohort before clinical use as a biomarker.