Genome-wide analysis of primary and secondary angiosarcomas using RNA extracted from formalin-fixed parafinembedded samples.
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ABSTRACT: Angiosarcomas are highly malignant tumors that develop as primary angiosarcomas of unknown cause or as secondary angiosarcomas, most often following radiation therapy for breast cancer. These subsets are morphologically indistinguishable, which motivates our aim to identify genetic classifiers for diagnostic and therapeutic application. We applied the 18k whole-genome c-DNA-mediated annealing, selection, extension, and ligation (WG-DASL) assay for expression profiling of 26 primary and 29 secondary angiosarcomas. Primary and secondary angiosarcomas differed by 103 significantly de-regulated genes with up-regulation of RET, KIT, FLT4, MYC and RASGRP3 and down-regulation of CDKN2C in secondary angiosarcoma. Functional annotation analysis demonstrated involvement of multiple target genes in the receptor protein tyrosine kinase pathway. Up-regulation of RET and down-regulation of CDKN2C characterize secondary angiosarcoma, which implies a mechanistic basis for the evaluation of RET-kinase inhibitors in the treatment of these highly aggressive tumors.
Project description:Angiosarcomas are highly malignant tumors that develop as primary angiosarcomas of unknown cause or as secondary angiosarcomas, most often following radiation therapy for breast cancer. These subsets are morphologically indistinguishable, which motivates our aim to identify genetic classifiers for diagnostic and therapeutic application. We applied the 18k whole-genome c-DNA-mediated annealing, selection, extension, and ligation (WG-DASL) assay for expression profiling of 26 primary and 29 secondary angiosarcomas. Primary and secondary angiosarcomas differed by 103 significantly de-regulated genes with up-regulation of RET, KIT, FLT4, MYC and RASGRP3 and down-regulation of CDKN2C in secondary angiosarcoma. Functional annotation analysis demonstrated involvement of multiple target genes in the receptor protein tyrosine kinase pathway. Up-regulation of RET and down-regulation of CDKN2C characterize secondary angiosarcoma, which implies a mechanistic basis for the evaluation of RET-kinase inhibitors in the treatment of these highly aggressive tumors. Total RNA obtained from primary and secondary angiosarcoma samples from formalin-fixed parafin-embedded samples were compared using WG-DASL. Biological replicates (two samples from the same patient, different parts of the tumor or different operation specimens) Technical replicates (two samples from the same patient and same tumor sample, analyzed in different areas of the bead chip)
Project description:The combined activation of KrasG12D and loss of Cdkn2a leads to aggressive angiosarcomas in aP2-Cre mice. Whereas, the conditional deletion of Tsc1 leads to vascular tumor formation that mimic human kaposiform hemangioendotheliomas. We used Affymetrix microarrays to compare angiosarcoma tumors with the combined activation of KrasG12D and loss of Cdkn2a and the conditional deletion of Tsc1
Project description:We generated RNA-Seq data from human angiosarcoma tissues (N=13) and non-malignant tissue samples (N=6). The goal of this study was to determine differentially expressed genes in the tumors compared to controls. We sequenced about 80 – 100 million sequence reads per sample and mapped to the human reference genome (GRCh38). We identified 1,237 differentially expressed genes between the tumors and non-malignant controls (FDR P-value < 0.05): 490 genes were upregulated and 747 genes were downregulated in angiosarcomas. Our results show a comprehensive data of fusion genes and gene expression profile in human angiosarcomas using RNA-seq technology.
Project description:We first use microRNA expression profiles to find miRNA expression signatures in 3 cases of human angiosarcoma and capillary hemangiomauman, then RT-PCR for large sample verification. Through the bioinformatics prediction of its target genes, we study its function and aim to find the new molecular markers and therapeutic targets. We identified the miRNA expression signatures in human angiosarcomas and capillary hemangiomas by using microRNA expression profiles
Project description:Angiosarcomas are rare malignant tumors of the endothelium, arising commonly from the head and neck region (AS-HN) and recently associated with ultraviolet (UV) exposure and human herpesvirus-7 (HHV-7) infection. We examined 81 cases of angiosarcomas, including 47 cases of AS-HN, integrating information from whole genome sequencing, gene expression profiling and spatial transcriptomics (10X Visium). In this dataset spatial transcriptomics revealed topological profiles of the tumor microenvironment, identifying dominant but tumor-excluded inflammatory signals in “immune-hot” cases and immune foci even in otherwise “cold” cases. In conclusion, spatial transcriptomics reveal the tumor immune landscape of angiosarcoma, and in combination with multi-omic information, may improve implementation of treatment strategies.
Project description:A series of mouse models designed to mimic pediatric medulloblastoma types in humans were tested by microarray and compared to published human medulloblastoma data Myc-type tumors [dka201-203] were generated by orthotopic injection of Myc-infected cerebellar cells from Cdkn2c-/-, Trp53-/-, Atoh1-GFP mice into the cerebral cortex of immunocompromised nude mice. For Shh-type medulloblastomas [dka204-206], spontaneous medulloblastomas from [Cdkn2c-/-; Trp53Fl/Fl; Nestin-Cre] (Uziel et al.,2005 Genes Dev) were used. FACS-sorted GFP-positive [dka220-222] and GFP-negative [dka211, 212 and 219] populations were obtained from postnatal day 6 Cdkn2c-/-, Trp53-/-, Atoh1-GFP cerebella. Myc-type secondary tumors [dka223-225] were generated by orthotopic transplantation of cultured sphere cells from Myc-type primary tumors.
Project description:Genetic variation in FLT4 is associated with the most prevalent cyanotic congenital heart disease,Tetralogy of Fallot (TOF). Distinct genetic variation in FLT4 is an established cause of Milroy disease, the prevailing form of primary hereditary lymphoedema. Phenotypic features of the conditions are non-overlapping, implying pleiotropic mechanisms. Here, TOF-associated FLT4 variants identified in patients,aggregate in the perinuclear/secretory pathway, activating proteostatic/metabolic signalling that lymphoedema-associated FLT4 variants do not. FLT4 TOF variants display characteristic gene expression changes in developmental signalling pathways, when expressed in undifferentiated human endothelial cells, revealing a role for FLT4 in cardiogenesis distinct from its role in lymphatic development. Inhibition of the main pathways of proteostasis abrogates these effects, identifying potential avenues for therapeutic intervention. We show that a gain-of-pathogenic-function mechanism causes TOF, contrasting with the dominant negative mechanism identified for Milroy-causative variants.This is among the first demonstrations that mechanistically elucidates developmental pleiotropy of thevascular system.
Project description:A transcriptome signature which discriminate efficiently primary and radiation induced breast angiosarcomas can be generated from FFPE tumor samples.FFPE samples are good material to unlock relevant informations from tumors. The transcriptome of 35 FFPE breast angiosarcomas (10 primary and 25 radiation induced) were analysed using Affymetrix Human Exon 1.0 ST arrays according to the FFPE dedicated protocole from NuGEN and compared to paired fresh frozen samples previously analysed. FF Samples are also available in Array Express as E-MEXP-3252.