Description
Type I low-grade gliomas (LGGs), characterized by 1p/19q co-deletions and IDH1/2 mutations, show superior overall survival compared to other gliomas. Approximately 70% of cases harbour mutations in the Capicua (CIC) gene, whose product is a transcriptional repressor whose transcriptional network has yet to be extensively studied in human cells. To address this, we developed CIC knockout cell lines and used transcriptome analyses to study the consequences of CIC loss. Results were further compared to data for Type I LGGs and stomach adenocarcinomas from The Cancer Genome Atlas (TCGA). We find that CIC appears to regulate the expression of genes involved in cell-cell adhesion and nervous system development. CIC deficiency is also found to be associated with a MEK activation transcriptional signature and to act as an effector of MEK signalling. Loss of CIC may thus present a novel mechanism for the dysregulation of this and other oncogenic pathways.