Daisuke Kawauchi, PhD
Group leader "Developmental neurooncology"
Hopp Children's Cancer Center Heidelberg
Im Neuenheimer Feld 580
Cancer results from multiple genetic mutations. These sequentially occurring mutations are thought to confer different cellular and molecular characteristics on transforming cells, causing inter- and intra-tumor heterogeneity. Therefore, understanding of how tumor cells arise from normal cells would enable us to propose rational therapeutic approaches for individual cancers.
Our group headed by Daisuke Kawauchi, PhD, which is also part of the DKFZ division Pediatric Neurooncology (headed by Prof. Dr. Stefan Pfister), investigates cellular and molecular mechanisms of brain development and brain tumor formation by focusing on genes that are recurrently mutated in pediatric brain tumors. For this purpose, we utilize molecular biology and biochemistry together with mouse genetics, iPS technology and next generation sequencing.
Recent studies of a whole genome landscape of human medulloblastoma revealed loss of function mutations in chromatin modifiers as a striking hallmark. Due to difficulty in getting enough primary cells for chromatin studies, little is known about roles of these identified chromatin modifiers in brain development. SHH-driven medulloblastoma is thought to arise from cerebellar granule cell progenitors (GNPs).
To understand in vivo function of chromatin modifiers mutated in SHH medulloblastoma in differentiation of GNPs, our group utilizes mouse genetics (e.g. knock-out mice) as well as CRISPR-cas9 technology. We furthermore deal with primary neural cells from mouse brains for subsequent chromatin analysis, such as ChIP-seq and ATAC-seq as well as in vivo and in vitro cell experiments.
The advancement of single cell sequencing technology offers us an opportunity to understand how cells differentiate from one state to another. In collaboration with the lab of Prof. Michael Boutros, we recently set up the droplet-based single cell RNA sequencing system for cerebellar primary cells. Using this system on genetically engineered mouse models (GEMMs), we are analyzing how GNPs transform into malignant SHH-driven medulloblastoma.
Feasible in vivo functional assays are required to accelerate identification of novel oncogenes and tumor suppressors. Electroporation-based gene transfer is a powerful tool to introduce genes efficiently into specific regions of mouse embryonic brains, such as forebrain, hindbrain, cerebellum and spinal cord. Our recent studies have shown that the combination of in utero electroporation with a Tol2-based genome integration system and CRISPR-Cas9 technology enables us to test oncogenic impacts on specific cerebellar cells. With internal and international collaborations, we are currently testing oncogenic impacts of potential oncogenes and tumor suppressor genes in vivo, resulting in the generation of rigid mouse models.
1. Kawauchi D et al. Novel MYC-driven medulloblastoma models from multiple embryonic cerebellar cells. Oncogene 2017. doi: 10.1038/onc.2017.110.
2. Feng W et al. Chd7 is indispensable for mammalian brain development through activation of a neuronal differentiation programme. Nat Commun. 2017. 8:14758
3. Zuckermann M et al. Somatic CRISPR/Cas9-mediated tumour suppressor disruption enables versatile brain tumour modelling. Nat Commun. 2015. 6:7391.
4. Kawauchi D et al. A mouse model of the most aggressive subgroup of human medulloblastoma. Cancer Cell. 2012. 21(2):168-80.