Project description:Glioblastoma (GB) is the most aggressive form of glioma and is characterized by a poor prognosis and high recurrence, despite intensive clinical interventions. To retrieve the key factors underlying the high malignancy of GB, we performed differential methylation analysis between low and high-grade gliomas by using Infinium MethylationEPIC beadchips.
Project description:Glioblastoma (GB) is the most aggressive form of glioma and is characterized by a poor prognosis and high recurrence, despite intensive clinical interventions. To retrieve the key factors underlying the high malignancy of GB, we performed differential expression analysis between low and high-grade gliomas by using RNA-seq.
Project description:We carried out the analyses of chromosome variations between low-grade and high-grade gliomas in Chinese population. We found out the differences in chromosomes, cytobands, genes, pathways and GO functions. To identify the glioma tissue-specific genomic alterations and compare the genomic variations between low-grade and high-grade gliomas.
Project description:We carried out the analyses of chromosome variations between low-grade and high-grade gliomas in Chinese population. We found out the differences in chromosomes, cytobands, genes, pathways and GO functions.
Project description:Low grade gliomas (LGG; WHO grade 2 astrocytomas, oligodendrogliomas and oligoastrocytomas) account for about 25% of diffuse gliomas. Most occur in young adults between the ages of 30 and 45 years, and are usually only diagnosed after a seizure. In general, they can be characterised by a long period of continuous slow growth, followed by malignant transformation that will be the cause of death up to 25 years after onset. However, there is a significant number of patients for whom malignant progression is more rapid, with mortality observed within 5 years. This suggests that, as with other tumour types, there may be different subtypes of LGG with specific prognosis. It follows that being able to identify these subtypes may permit better patient stratification and aid targeted treatments. Until recently, our understanding of the variables involved in patient prognosis included the type of tumour oligodendroglial tumours indicate better prognosis than oligoastrocytic or astrocytic and presence of the 1p-19q co-deletion. In addition, the recent discovery of mutations in IDH1&2 in the majority of LGGs provided another means of stratifying patients, while offering an important insight into their biology. However, we still understand very little of the biology behind the genesis and progression of the 70-80% of LGG that bear IDH1&2 mutations, let alone the remaining IDH wild-type tumours.
Project description:<p>Pediatric low-grade gliomas (PLGGs) are among the most common solid tumors in children but, apart from mutations or duplications in the BRAF kinase in specific subclasses, few genetic driver events are known. Diffuse PLGGs compose a set of uncommon subtypes that exhibit invasive growth and are therefore especially challenging clinically. These tumors are particularly poorly understood. We performed high-resolution copy-number analysis of 44 diffuse PLGGs to identify recurrent alterations. Diffuse PLGGs exhibited fewer such alterations than adult low-grade gliomas, but we identified several significantly recurrent events. The most significant event, 8q13.1 gains, was observed in 28% of diffuse astrocytoma WHO grade II (DA2) and resulted in partial duplication of the transcription factor MYBL1 with truncation of its C-terminal negative-regulatory domain. A similar recurrent deletion-truncation breakpoint was identified in two angiocentric gliomas in the related gene MYB on 6q23.3. Whole genome sequencing of a MYBL1-rearranged diffuse astrocytoma grade II demonstrated MYBL1 tandem duplication and few other events. Two truncated MYBL1 transcripts identified in this tumor induced anchorage-independent growth when expressed in 3T3 cells and tumor formation in nude mice. Truncated transcripts were also expressed in two additional tumors with MYBL1 partial duplication. Our results define clinically relevant molecular subclasses of diffuse PLGGs and highlight a potential role for the MYB family in the biology of low-grade gliomas. "Reprinted from www.pnas.org/cgi/doi/10.1073/pnas.1300252110 with permission from PNAS." </p>