Funding outcome

The DLX2 protein is a transcription factor that regulates the activity of several genes that determine cell fate. In the developing brain, DLX2 gene regulation promotes the maturation of inhibitory (GABAergic) interneurons as well as decreases the development of cells called oligodendrocytes which make myelin that help nerve transmission. DIPG tumours occur in children and are always fatal despite improvements in therapy. The cell of origin of DIPG is considered to be a precursor of oligodendrocytes due to similarities in their nature. Since DLX2 is able to suppress the formation of mature oligodendrocytes, it is possible that increasing the level of Dlx2 in these tumours may suppress the growth and invasion of DIPG cells as well. In our laboratory, mouse DIPG cell lines have decreased growth and spread when the Dlx2 gene has been introduced into the cells. Epigenetic markers that signal decreased transcription of many genes are normally missing in these mouse DIPG cell lines but are restored with the increase in Dlx2 gene expression. With this in mind, we hypothesized that human patient derived DIPG cell lines will respond in a similar way as the mouse lines when Dlx2 is introduced and have decreased growth and spread. The human DIPG cell lines will be grown and Dlx2 or control gene constructs with a fluorescent tag will be introduced into the cells. After several rounds of selection, the cell culture will contain only cells that have taken up the Dlx2 construct. A technique called Western blot which detects proteins will test for the appearance of the epigenetic repressive marker. PCR will be used to test for the expression of several genes that DLX2 regulates. I expect that there will be restoration of the repressive marker as well as a significant difference between gene expression between Dlx2 and negative control cells. This project will give further insight into this fatal pediatric brainstem tumour and may contribute to development of differentiation-based therapy