BRM CHROMOTHRIPSIS · Dissecting Cancer Development by Chromothripsis Using Cell-Based Models

Dissecting Cancer Development by Chromothripsis Using Cell-Based Models

Cancer is commonly thought as a progressive process, requiring accumulation of many mutations over time. Recently, this conventional view of cancer progression has been challenged with the discovery of a phenomenon called chromothripsis, whereby tens to hundreds of chromosomal rearrangements occur in a single catastrophic event. Despite the growing amount of sequencing data that sheds some light on the nature of these structural variations, the molecular mechanisms behind these detrimental alterations are unclear largely due to lack of suitable in vitro models. Overall aim of this research project was to investigate the molecular mechanisms of chromothripsis by generation, screening and evaluation of somatic structural variants in vitro. For this reason, we generated human cell lines with various genetic backgrounds that were prone to accumulate persistent DNA damage and were therefore used for a systematic analysis on potential mechanisms leading to massive chromosome breakages. We applied an integrative approach enabling efficient generation of complex structural DNA rearrangements in vitro by perturbing karyotypically normal cells and subsequent analysis by massively-parallel sequencing. Following this approach, we reproducibly produced cell lines exhibiting this catastrophical phenomenon, i.e. chromothripsis, and analyzed them in detail. The occurrence of chromothripsis was apparent at a significant propensity in cells with specific genetic backgrounds. Our findings in vitro were confirmed in vivo analyzing primary human cancer genomes. Taken together, the results of this project provide critical information on the molecular mechanisms behind chromothripsis and set a foundation for future mechanistic studies, which might contribute to the understanding of cancer progression.

Data: CORDIS, © European Union