GSE59720
Human somatic cell mutagenesis creates genetically tractable sarcomas
Creating spontaneous yet genetically tractable human tumors from normal cells presents a fundamental challenge. Retroviruses and transposons have been separately used as somatic cell insertional mutagens to identify cancer drivers in model organisms. Here we combined these mutagenic elements to enable cancer gene discovery starting with normal human cells. Lentivirus was used to seed gain- and loss-of-function gene disruption elements which were further deployed by Sleeping Beauty transposons throughout the genome of human bone explant mesenchymal cells. De novo tumors rapidly generated in this context were high-grade sarcomas corresponding to the spectrum of myxofibrosarcoma and undifferentiated pleomorphic sarcoma, aggressive neoplasms with a predilection for older adults. Tumor insertion sites were genome-wide and enriched in regions of recurrent somatic copy number alteration found in multiple cancers, with a bias towards those of sarcomas. Novel driver genes which sustain somatic alterations in cancer patients were pinpointed. We identify the gene HDLBP, which codes for the RNA binding protein vigilin, as a candidate tumor suppressor deleted at 2q37.3 in greater than one in ten tumors across multiple tissues of origin. Hybrid viral-transposon systems will accelerate the functional annotation of cancer genomes by enabling insertional mutagenesis screens in higher eukaryotes that are not amenable to germline transgenesis. Overall design: Lentivirus was used to seed gain- and loss-of-function gene disruption elements which were further deployed by Sleeping Beauty (SB) transposons throughout the genome of human bone explant mesenchymal cells. Genomic locations of LV (lentiviral backbone) and SB insertion sites were mapped by a pooled strategy utilizing linear amplification mediated PCR (LAM-PCR), followed by Illumina next generation sequencing of the product pool.