Abstract 3482: SNORD-X in glioblastoma: regulation and functional analysis

Glioblastoma Multiforme (GBM) is a kind of brain tumor which arises from astrocytes present in the brain. It represents approximately 15% of all primary brain tumor and has been considered as one of the deadliest type of cancer with very poor prognosis. Thus, there is an urgent need to identify novel targets for GBM therapy. Recently, non-coding RNAs (ncRNAs) such as miRNAs and lncRNAs have emerged as one of the promising tools as diagnostic or prognostic biomarkers and as novel targets for therapy. There are recent evidences that small nucleolar RNAs (snoRNAs), a subtype of ncRNAs might also play a key role in various cancers. In this context, we aimed at studying the role of snoRNAs in GBM. For this, we did snoRNA profiling in GBM patients and found that a particular cluster of snoRNA called SNORD-X was highly downregulated in adult as well as pediatric GBM patients. We also found SNORD-X promoter to be methylated and shows maternal imprinting. We next did functional analyses of SNORD-X by generation of an overexpression construct. Our preliminary data suggests that overexpression of SNORD-X in GBM cell lines (U87MG and A172) increases cell proliferation in vitro. It also enhances the colony forming capability of GBM cells. Further, its overexpression causes decrease in apoptosis in a caspase-dependent manner. A target analysis of SNORD-X was done using RNAhybrid software. We found EGR1, DCUN1D3 and BRCA1 to be the direct targets of SNORD-X using a combination of qRT-PCR and wild-type/mutated 3’UTR luciferase analyses. Overall, our work shows for the first time correlation and functional analysis of SNORD-X cluster in GBM. Citation Format: Shikha Gupta, Prerana Jha, Chitra Sarkar, Ritu Kulshreshtha. SNORD-X in glioblastoma: regulation and functional analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3482. doi:10.1158/1538-7445.AM2017-3482